User’s Guide
Agilent Technologies
E4428C/38C ESG Signal Generators
This guide applies to the following signal generator models:
E4428C ESG Analog Signal Generator
E4438C ESG Vector Signal Generator
Due to our continuing efforts to improve our products through firmware and hardware revisions, signal
generator design and operation may vary from descriptions in this guide. We recommend that you use the
latest revision of this guide to ensure you have up-to-date product information. Compare the print date of this
guide (see bottom of page) with the latest revision, which can be downloaded from the following website:
http://www.agilent.com/find/esg
Manufacturing Part Number: E4400-90503
Printed in USA
July 2009
© Copyright 2001-2009 Agilent Technologies, Inc.
Notice
The material contained in this document is provided “as is”, and is subject to being changed, without notice,
in future editions.
Further, to the maximum extent permitted by applicable law, Agilent disclaims all warranties, either
expressed or implied with regard to this manual and to any of the Agilent products to which it pertains,
including but not limited to the implied warranties of merchantability and fitness for a particular purpose.
Agilent shall not be liable for errors or for incidental or consequential damages in connection with the
furnishing, use, or performance of this document or any of the Agilent products to which it pertains. Should
Agilent have a written contract with the User and should any of the contract terms conflict with these terms,
the contract terms shall control.
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Contents
1. E4428C Analog Signal Generator Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Standard Analog Signal Generator Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Firmware Upgrades. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
To Upgrade Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Continuous Wave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Swept Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Analog Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Front Panel Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
1. Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2. Softkeys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
3. Frequency Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
4. Amplitude Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
5. Knob . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
7. Save Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
7. Menu Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
8. Recall Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
9. EXT 1 INPUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
10. EXT 2 INPUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
11. Help Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
12. Trigger Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
13. LF OUTPUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
14. RF OUTPUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
15. Mod On/Off Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
16. RF On/Off Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
17. Numeric Keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
18. Incr Set Key. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
19. Arrow Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
20. Hold Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
21. Return Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
22. Display Contrast Increase Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
23. Display Contrast Decrease Key. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
24. Local Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
25. Preset Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
26. Standby LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
27. Line Power LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
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28. Power Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Front Panel Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
1. Frequency Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2. Annunciators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3. Amplitude Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4. Softkey Label Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5. Error Message Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6. Text Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
7. Active Function Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Rear Panel Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
1. AC Power Receptacle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2. GPIB Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3. RS 232 Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4. LAN Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5. TRIG OUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6. TRIG IN Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7. 10 MHz IN Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
8. SWEEP OUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
9. 10 MHz OUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2. E4438C Vector Signal Generator Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Standard Vector Signal Generator Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Understanding Baseband Generator Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Firmware Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
To Upgrade Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Continuous Wave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Swept Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Analog Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Digital Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Front Panel Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
1. Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2. Softkeys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3. Frequency Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4. Amplitude Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
5. Knob . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
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6. Menu Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
7. Save Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
8. Recall Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
9. EXT 1 INPUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
10. EXT 2 INPUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
11. Help Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
12. Trigger Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
13. LF OUTPUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
14. RF OUTPUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
15. Mod On/Off Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
16. RF On/Off Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
17. Numeric Keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
18. Incr Set Key. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
19. Arrow Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
20. Hold Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
21. Return Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
22. Display Contrast Increase Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
23. Display Contrast Decrease Key. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
24. Local Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
25. Preset Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
26. Standby LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
27. Line Power LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
28. Power Switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
29. SYMBOL SYNC Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . .31
30. DATA CLOCK Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
31. DATA Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
32. Q Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
33. I Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Front Panel Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
1. Frequency Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
2. Annunciators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
3. Digital Modulation Annunciators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
4. Amplitude Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
5. Softkey Label Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
6. Error Message Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
7. Text Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
8. Active Function Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Rear Panel Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
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1. 321.4 IN Connector (Option 300). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
2. BER GATE IN Connector (Option UN7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3. BER CLK IN Connector (Option UN7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4. BER DATA IN Connector (Option UN7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
5. I-bar OUT Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
6. I OUT Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
7. COH CARRIER Output Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
8. Q OUT Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9. Q-bar OUT Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
10. EVENT 1 Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
11. EVENT 2 Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
12. PATT TRIG IN Connector (Option 001/601 or 002/602). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
13. AUX I/O Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
14. DIGITAL BUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
15. AC Power Receptacle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
16. GPIB Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
17. RS 232 Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
18. LAN Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
19. TRIG OUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
20. BURST GATE IN Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . 45
21. TRIG IN Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
22. 10 MHz IN Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
23. SWEEP OUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
24. 10 MHz OUT Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
25. BASEBAND GEN REF IN Connector (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . 46
3. Basic Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Using Table Editors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Table Editor Softkeys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Modifying Table Items in the Data Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Configuring the RF Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Configuring a Continuous Wave RF Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Configuring a Swept RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Generating the Modulation Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Modulating the Carrier Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
To Turn the Modulation On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
To Turn the Modulation Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Creating and Applying User Flatness Correction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
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Creating a User Flatness Correction Array . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61
Using the Memory Catalog. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Viewing Stored Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Storing Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
Using the Instrument State Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
Saving an Instrument State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
Recalling an Instrument State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
Saving an Instrument State for a Waveform File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
Recalling an Instrument State for a Waveform File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
Deleting Registers and Sequences. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
Using Security Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Understanding Memory Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Removing Sensitive Data from Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
Using the Secure Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82
Enabling Options (E4438C Only). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
Enabling a Software Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
Using the Web Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
Activating the Web Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
4. Basic Digital Operation (Option 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89
Custom Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Custom ARB Waveform Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Custom Real Time I/Q Baseband . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
Arbitrary (ARB) Waveform File Headers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93
Creating a File Header. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93
Modifying Header Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
Dual ARB Player Waveform Sequence File Headers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
Editing and Viewing File Headers in the Dual ARB Player . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
Playing a Waveform File containing a Header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105
Using the Dual ARB Waveform Player . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107
Accessing the Dual ARB Player . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107
Creating Waveform Segments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108
Creating a Waveform Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109
Playing a Waveform Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Editing a Waveform Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Adding Real Time Noise to a Dual ARB Waveform (Option 403) . . . . . . . . . . . . . . . . . . . . . . . 112
Storing and Loading Waveform Segments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Understanding the I/Q Modulator Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
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Applying An I/Q Modulator Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Local Settings for ARB Waveform Formats and the Dual ARB Player . . . . . . . . . . . . . . . . . . . . . 117
I/Q Attenuator and Filters Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Waveform Runtime Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
High Crest Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
ARB Sample Clock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Waveform Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Using Waveform Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Waveform Marker Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Accessing Marker Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Viewing Waveform Segment Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Clearing Marker Points from a Waveform Segment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Setting Marker Points in a Waveform Segment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Controlling Markers in a Waveform Sequence (Dual ARB Only) . . . . . . . . . . . . . . . . . . . . . . . . 134
Viewing a Marker Pulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Using the RF Blanking Marker Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Setting Marker Polarity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Triggering Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Mode and Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Accessing Trigger Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Setting the Polarity of an External Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Using Gated Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Using Segment Advance Triggering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Using External Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Using Waveform Clipping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
How Power Peaks Develop. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
How Peaks Cause Spectral Regrowth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
How Clipping Reduces Peak-to-Average Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
Configuring Circular Clipping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Configuring Rectangular Clipping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Using Waveform Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
How DAC Over-Range Errors Occur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
How Scaling Eliminates DAC Over-Range Errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Scaling a Currently Playing Waveform (Runtime Scaling) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Scaling a Waveform File in Volatile Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Using Customized Burst Shape Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Understanding Burst Shape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
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Creating a User-Defined Burst Shape Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163
Storing a User-Defined Burst Shape Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166
Recalling a User-Defined Burst Shape Curve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166
Generating the Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167
Using Finite Impulse Response (FIR) Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168
Creating a User-Defined FIR Filter Using the FIR Table Editor . . . . . . . . . . . . . . . . . . . . . . . . .168
Modifying a FIR Filter Using the FIR Table Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173
Loading the Default Gaussian FIR File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173
Modifying the Coefficients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174
Storing the Filter to Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174
Differential Encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175
Differential Data Encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .176
How Differential Encoding Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177
Using Differential Encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179
User-Defined I/Q Maps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183
Creating a User-Defined I/Q Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183
Storing a User-Defined I/Q Map File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185
Moving I/Q Symbols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185
User-Defined FSK Modulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187
Modifying a Default FSK Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187
Storing an FSK Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188
Creating a User-Defined FSK Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188
Creating and Using Bit Files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190
Creating a User File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190
Renaming and Saving a User File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192
Recalling a User File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193
Modifying an Existing User File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193
Applying Bit Errors to a User File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194
Waveform Licensing for Firmware Version ≥ C.05.23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195
Understanding Waveform Licensing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195
Installing an E4438C Option 22x or E4438C Option 25x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195
Licensing a Signal Generator Waveform File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196
Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version < C.05.23 . . . . . . .197
Understanding Waveform 5-Pack Licensing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197
Installing an E4438C Option 22x Waveform 5-Pack License . . . . . . . . . . . . . . . . . . . . . . . . . . .198
Licensing a Signal Generator Waveform File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .198
Using Waveform 5-Pack History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200
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Waveform 5-Pack Warning Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
Waveform Licenses (Signal Studio “A” Versions). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
5. AWGN Waveform Generator (Option 403) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Configuring the AWGN Generator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Arb Waveform Generator AWGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Real Time I/Q Baseband AWGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
6. Analog Modulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Analog Modulation Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Configuring AM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Setting the Carrier Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Setting the RF Output Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Setting the AM Depth and Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Turning on Amplitude Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Wideband AM (E4438C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
Configuring FM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Setting the RF Output Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Setting the RF Output Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Setting the FM Deviation and Rate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Activating FM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Configuring ΦM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Setting the RF Output Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Setting the RF Output Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Setting the FM Deviation and Rate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Activating FM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Configuring Pulse Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Setting the RF Output Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Setting the RF Output Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Setting the Pulse Period and Width. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Activating Pulse Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Configuring the LF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Configuring the LF Output with an Internal Modulation Source . . . . . . . . . . . . . . . . . . . . . . . . . 217
Configuring the LF Output with a Function Generator Source . . . . . . . . . . . . . . . . . . . . . . . . . . 218
7. Digital Signal Interface Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
Clock Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Clock and Sample Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
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Clock Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223
Common Frequency Reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224
Clock Timing for Parallel Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227
Clock Timing for Parallel Interleaved Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230
Clock Timing for Serial Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232
Clock Timing for Phase and Skew Adjustments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232
Connecting the Clock Source and the Device Under Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234
Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236
Output Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236
Input Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236
Operating the N5102A Module in Output Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238
Setting up the Signal Generator Baseband Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238
Accessing the N5102A Module User Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238
Choosing the Logic Type and Port Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239
Selecting the Output Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240
Selecting the Data Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240
Configuring the Clock Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242
Generating Digital Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246
Operating the N5102A Module in Input Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247
Accessing the N5102A Module User Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247
Selecting the Input Direction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248
Choosing the Logic Type and Port Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248
Configuring the Clock Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249
Selecting the Data Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253
Digital Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255
8. Bluetooth Signals (Option 406) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257
Accessing the Bluetooth Setup Menu on the ESG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258
Setting Up Packet Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259
Setting up Impairments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261
Using Burst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263
Setting the Burst Power Ramp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263
Using Clock/Gate Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264
Turning On a Bluetooth Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265
9. BERT (Options UN7 and 300) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .267
Setting Up a PHS Bit Error Rate Test (BERT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268
Required Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268
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Connecting the Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Setting the Carrier Frequency and Power Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Selecting the Radio Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Setting the Radio to a Receiver Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Selecting the BERT Data Pattern and Total Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Selecting the BERT Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Starting BERT measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Measuring RF Loopback BERT with Option 300 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Required Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Connecting the Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Configuring GSM Mode on the Agilent Technologies E4406A VSA Series Transmitter Tester 275
Configuring GSM Mode on the ESG Vector Signal Generator . . . . . . . . . . . . . . . . . . . . . . . . . . 276
Synchronizing to the BCH Then the TCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
Synchronizing to the TCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
Making Loopback BERT Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Using Amplitude Sensitivity Search. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Using the External Frame Trigger Function with the EDGE Format. . . . . . . . . . . . . . . . . . . . . . . . 288
Measuring the Initial Delay Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
Adjusting the Delay Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
Bit Error Rate Tester–Option UN7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292
Clock Gate Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292
Clock/Gate Delay Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293
Clock Delay Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Gate Delay Function in the Clock Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Data Processing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
Repeat Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
Testing Signal Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
RF Loopback BER–Option 300 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Erased Frame Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304
Downlink Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304
Frame Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304
Verifying BERT Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Verification Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
10. CDMA Digital Modulation (Option 401) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311
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cdma2000 Forward Link Modulation for Component Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .312
Activating a Predefined CDMA Forward Link State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .312
Creating a User-Defined CDMA Forward Link State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .313
cdma2000 Reverse Link Modulation for Component Test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .316
Activating a Predefined cdma2000 Reverse Link State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .316
Creating a User-Defined cdma2000 Reverse Link State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .317
Storing a Component Test Waveform to Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .320
Recalling a Component Test Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .321
Creating a Custom Multicarrier cdma2000 Waveform. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .322
Opening the Multicarrier cdma2000 Setup Table Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .322
Modifying a Multicarrier cdma2000 4-Carrier Template . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .323
Activating a Custom Multicarrier cdma2000 Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .324
cdma2000 Forward Link Modulation for Receiver Test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .326
Editing the Base Station Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .326
Editing Channel Setups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .326
Adjusting Code Domain Power. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .328
Managing Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .329
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .330
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .331
cdma2000 Reverse Link Modulation for Receiver Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .332
Editing the Mobile Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .332
Editing Channel Setups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .332
Adjusting Code Domain Power. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .334
Managing Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .335
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .336
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .337
Forward and Reverse Link I/O Signal Descriptions and Timing Relationships. . . . . . . . . . . . . . . .338
Front Panel Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .338
Rear Panel Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .339
Rear Panel Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .339
Forward Link I/O Timing Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .341
Reverse Link I/O Timing Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .343
Applying a User-Defined FIR Filter to a cdma2000 Waveform. . . . . . . . . . . . . . . . . . . . . . . . . . . .347
IS-95A Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .349
Creating a Predefined CDMA State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .349
Creating a User-Defined CDMA State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .350
Applying Changes to an Active CDMA State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .352
Creating a User-Defined Multicarrier CDMA State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .352
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Applying Changes to an Active Multicarrier CDMA State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354
11. GPS Modulation (Option 409) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
Real Time MSGPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356
Signal Generation Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 357
Scenario Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358
RF Power Level Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359
Generating a Real Time MSGPS Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
Configuring the External Reference Clock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 362
Real Time GPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
Real Time GPS Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
Setting Up the Real Time GPS Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Configuring the External Reference Clock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
Testing Receiver Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
Setting Up a GPS Bit Error Rate Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373
12. Multitone Waveform Generator (Options 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . 377
Creating a Custom Multitone Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Initializing the Multitone Setup Table Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Configuring Tone Powers and Tone Phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Removing a Tone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Generating the Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
Applying Changes to an Active Multitone Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380
Storing a Multitone Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380
Recalling a Multitone Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381
13. Custom Digital Modulation (Options 001/601 or 002/602) . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
Using the Arbitrary Waveform Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384
Using Predefined Custom TDMA Digital Modulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384
Creating a Custom TDMA Digital Modulation State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385
Storing a Custom TDMA Digital Modulation State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 386
Recalling a Custom TDMA Digital Modulation State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 386
Creating a Custom Multicarrier TDMA Digital Modulation State. . . . . . . . . . . . . . . . . . . . . . . . 387
Storing a Custom Multicarrier TDMA Digital Modulation State. . . . . . . . . . . . . . . . . . . . . . . . . 389
Applying Changes to an Active Multicarrier TDMA Digital Modulation State . . . . . . . . . . . . . 389
Using the Real Time I/Q Baseband Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390
Selecting Predefined Custom Modulation Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390
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Creating User-Defined Custom Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .391
14. Real Time TDMA Formats (Option 402). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .393
EDGE Framed Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .394
Understanding External Data Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .394
Activating Framed Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .395
Configuring the EDGE Timeslots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .395
Configuring GMSK Timeslots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .395
Disabling Timeslot Ramping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .396
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .396
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .396
Adjusting the Power Level Between Timeslots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .396
GSM Framed Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .398
Activating Framed Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .398
Configuring the First Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .398
Configuring the Second Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .398
Configuring the Third Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .398
Disabling Timeslot Ramping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .399
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .399
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .399
Adjusting the Power Level Between Timeslots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .399
Enhanced Observed Time Difference (E-OTD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .400
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .400
Basic GSM Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .400
E-OTD Measurement System Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .406
Sample SCPI Command Scripts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .409
DECT Framed Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .413
Activating Framed Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .413
Configuring the First Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .413
Configuring the Second Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .413
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .413
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .414
PHS Framed Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .415
Activating Framed Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .415
Configuring the First Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .415
Configuring the Second Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .415
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .415
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .416
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PDC Framed Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417
Activating Framed Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417
Configuring the First Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417
Configuring the Second Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
NADC Framed Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
Activating Framed Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
Configuring the First Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
Configuring the Second Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 420
TETRA Framed Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
Activating Framed Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
Configuring the First Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
Configuring the Second Timeslot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
15. W-CDMA Digital Modulation for Component Test (Option 400) . . . . . . . . . . . . . . . . . . . . . . . . 423
W-CDMA Downlink Modulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 424
Activating a Predefined W-CDMA Downlink State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 424
Creating a User-Defined W-CDMA Downlink State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 425
Storing a W-CDMA Downlink/Uplink State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
Recalling a W-CDMA Downlink/Uplink State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430
Creating a User-Defined Multicarrier W-CDMA State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 431
Storing a Multicarrier W-CDMA State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 434
Recalling a Multicarrier W-CDMA State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435
W-CDMA Uplink Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 436
Creating a Predefined W-CDMA Uplink State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 436
Creating a User-Defined W-CDMA Uplink State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 437
W-CDMA Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441
Understanding TPC Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 443
Understanding TFCI, TPC, and Pilot Power Offsets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 444
Calculating Downlink Scramble Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 446
W-CDMA Frame Structures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
Downlink PICH Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
Downlink PCCPCH + SCH Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451
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Downlink DPCCH/DPDCH Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .452
Uplink DPCCH/DPDCH Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .454
16. W-CDMA Uplink Digital Modulation for Receiver Test (Option 400) . . . . . . . . . . . . . . . . . . . .457
Equipment Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .459
ESG and Agilent E4440A PSA Spectrum Analyzer Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .459
ESG and Base Transceiver Station (BTS) Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .459
Understanding the PRACH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .461
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .461
Access Slots. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .461
Preamble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .462
Message Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .463
Power Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .465
Power Control Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .471
Generating a Single PRACH Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .474
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .474
Selecting the PRACH and Single PRACH Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .474
Selecting a Rear Panel Output Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .474
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .475
Setting Up the E4440A PSA for the PRACH Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .475
Modifying the PRACH Physical and Transport Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .476
Viewing the Modified PRACH Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .480
Generating the AICH for the PRACH Message Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . .480
Viewing the PRACH Message Using an AICH Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .483
Using the AICH Feature with a Base Transceiver Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .484
Multiple PRACH Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .486
Understanding the 80 ms Transmission/Time Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .486
Understanding the Power Offset Between the Carrier and the Multiple PRACH . . . . . . . . . . . .489
Setting Up a Multiple PRACH Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .491
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .491
Selecting the PRACH and Multiple PRACH Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .492
Selecting the Rear Panel Output Trigger. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .492
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .493
Configuring the PRACH Code Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .493
Configuring the PRACH Power Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .499
Configuring the PRACH Timing Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .502
Viewing a Multiple PRACH Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .507
Connecting the ESG to a Base Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .508
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Overload Testing with Multiple PRACHs—Multiple ESGs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 509
Connecting the ESG to the Base Transceiver Station. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 511
Configuring the ESGs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512
Setting Up the LF Output as the PRACH Start Trigger Signal . . . . . . . . . . . . . . . . . . . . . . . . . . 515
DPCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 516
Generating a DPCCH/DPDCH with a Reference Measurement Channel . . . . . . . . . . . . . . . . . . 516
Configuring the E4440A PSA for Viewing the DPCCH/DPDCH Output . . . . . . . . . . . . . . . . . . 517
Modifying the DPCCH/DPDCH Physical and Transport Layers. . . . . . . . . . . . . . . . . . . . . . . . . 518
Configuring the E4440A PSA for Viewing Additive Noise. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 522
Adding Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 522
Using the Transmit Power Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525
Compressed Mode Single Transmission Gap Pattern Sequence (TGPS) Overview . . . . . . . . . . . . 529
Setting Up Compressed Mode for a Single TGPS Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . 531
Equipment Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 531
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 531
Accessing the W-CDMA Modulation Format and Selecting Uplink . . . . . . . . . . . . . . . . . . . . . . 532
Setting UP the W-CDMA Signal Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 532
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 533
Configuring Compressed Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 533
Viewing and Adjusting the Compressed Mode Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537
Compressed Mode Multiple Transmission Gap Pattern Sequence (TGPS) Overview . . . . . . . . . . 540
Understanding Multiple TGPS Compressed Frame Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . 540
Setting Up Compressed Mode for a Multiple TGPS Transmission . . . . . . . . . . . . . . . . . . . . . . . . . 543
Equipment Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 543
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 543
Accessing the W-CDMA Modulation Format and Selecting Uplink . . . . . . . . . . . . . . . . . . . . . . 544
Setting UP the W-CDMA Signal Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 544
Selecting the Rear Panel Output Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 545
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 545
Configuring TGPSI 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 546
Configuring TGPSI 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 549
Viewing the Multiple TGPSI Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 552
Configuring the UE Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 554
Locating Rear Panel Input Signal Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 555
Configuring Rear Panel Output Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557
Accessing the Output Trigger Signal Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557
Selecting an Output Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557
Deselecting an Output Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 559
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Adjusting Code Domain Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .560
Scaling to 0 dB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .560
Setting Equal Channel Powers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .561
W-CDMA Uplink Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .562
Data Channel Air Interface Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .562
Reference Measurement Channels (RMC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .562
Transition between Normal Frame and Compressed Frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . .563
Settling Time during User Event for DPCH Compressed Mode . . . . . . . . . . . . . . . . . . . . . . . . .564
Connecting the ESG to a W-CDMA Base Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .564
Connector Assignments for W-CDMA Uplink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .565
Signal Descriptions for W-CDMA Uplink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .569
Synchronization Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .574
Frame Sync Trigger Status Indicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .579
Special Power Control Considerations When Using DPCCH/DPDCH in Compressed Mode or
PRACH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .582
W-CDMA AWGN Measurements and Bandwidths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .583
DPCH Transmit Power Control by an External Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .585
DPCCH/DPDCH Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .587
17. W-CDMA Downlink Digital Modulation for Receiver Test (Option 400) . . . . . . . . . . . . . . . . . .589
Using W-CDMA Downlink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .590
Configuring the Base Station Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .590
Configuring the Physical Layer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .591
Configuring the Transport Layer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .592
Adjusting Code Domain Power. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .593
Managing Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .595
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .596
Applying New Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .596
Configuring the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .597
Transmit Diversity Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .598
Configuring for Transmit Diversity and BERT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .601
Equipment Set Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .601
Configuring the RF Output for both ESGs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .602
Accessing the W-CDMA Modulation Format and Selecting Downlink. . . . . . . . . . . . . . . . . . . .603
Setting UP Antenna One (ESG One) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .603
Setting UP Antenna Two (ESG Two) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .607
Generating the Baseband Signals and Synchronizing the ESG Transmissions . . . . . . . . . . . . . .609
Configuring the UE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .609
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Making the BERT Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 610
Out-of-Synchronization Testing Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 612
Configuring for Out-of-Synchronization Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 613
Equipment Set up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 613
Setting the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 614
Accessing the W-CDMA Modulation Format and Selecting Downlink . . . . . . . . . . . . . . . . . . . 615
Setting UP the W-CDMA Signal Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 615
Selecting the Input DTX Gating Signal Trigger Polarity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 616
Generating the Baseband Signal and Activating the Out-Of-Synchronization Test Feature . . . . 617
Configuring the UE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 617
Setting Up the Spectrum Analyzer for Detecting the UE DTX . . . . . . . . . . . . . . . . . . . . . . . . . . 617
Configuring the DPCH DTX Gating Trigger Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 618
Compressed Mode Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 619
Setting Up for a Compressed Mode Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 622
Equipment Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 622
Setting the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 624
Accessing the W-CDMA Modulation Format and Selecting Downlink . . . . . . . . . . . . . . . . . . . 625
Setting Up the W-CDMA Signal Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625
Generating the Baseband Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 626
Configuring Compressed Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 626
Making Compressed Mode Signal Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 631
Measuring the DPCH Symbol Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 631
Making the BERT Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 635
Locating Rear Panel Input Signal Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 637
Configuring Rear Panel Output Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639
Accessing the Rear Panel Output Signal Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639
Selecting an Output Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639
Deselecting an Output Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 640
Rear Panel Output Signal Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
W-CDMA Downlink Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 644
DPCH Coding Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 644
Reference Measurement Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 644
Scramble Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 646
W-CDMA AWGN Measurements and Bandwidths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 647
Special Power Control Considerations When Using Compressed Mode . . . . . . . . . . . . . . . . . . . 650
W-CDMA Frame Structures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 651
Downlink PICH Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 651
Downlink PCCPCH + SCH Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 652
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Downlink DPCCH/DPDCH Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .653
18. Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .655
Basic Signal Generator Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .656
Cannot Turn Off Help Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .656
No RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .656
Signal Loss While Working with Mixers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .657
Signal Loss While Working with Spectrum Analyzers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .658
RF Output Power too Low . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .660
No Modulation at the RF Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .661
Sweep Appears to be Stalled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .661
Cannot Turn Off Sweep Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .661
Incorrect List Sweep Dwell Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .662
List Sweep Information is Missing from a Recalled Register . . . . . . . . . . . . . . . . . . . . . . . . . . .662
Data Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .663
Signal Generator Lock-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .664
Fail-Safe Recovery Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .664
Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .666
Error Message File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .666
Error Message Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .667
Error Message Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .668
Upgrading Firmware. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .669
Returning a Signal Generator to Agilent Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .670
Contacting Agilent Sales and Service Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .671
xxi
Contents
xxii
Documentation Overview
Installation Guide
•
•
•
•
Safety Information
Getting Started
Operation Verification
Regulatory Information
User’s Guide
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
E4428C Analog Signal Generator Overview
E4423C Analog Signal Generator Overview
Basic Operation
Basic Digital Operation
AWGN Waveform Generator
Analog Modulation
Digital Signal Interface Module
Bluetooth Signals
BERT
CDMA Digital Modulation
GPS Modulation
Multitone Waveform Generator
Custom Digital Modulation
Real Time TDMA Formats
W- CDMA Digital Modulation for Component Test
W- CDMA Uplink Digital Modulation for Receiver Test
W- CDMA Downlink Digital Modulation for Receiver Test
Troubleshooting
Programming Guide
•
•
•
•
•
•
Getting Started with Remote Operation
Using IO Interfaces
Programming Examples
Programming the Status Register System
Creating and Downloading Waveform Files
Creating and Downloading User- Data Files
xxiii
SCPI Reference
Volume 1:
•
•
•
•
•
SCPI Basics
Basic Function Commands
System Commands
Analog Commands
Component Test Digital Commands
Volume 2:
• Digital Signal Interface Module Commands
• Bit Error Rate Test (BERT) Commands
• Receiver Test Digital Commands
Volume 3:
• Receiver Test Digital Commands (continued)
Compatibility with
E44xxB SCPI
Commands
•
•
•
•
•
Overview
E4428C/38C SCPI Commands
ESG E44xxB Commands
8648A/B/C/D Commands
8658B, 8657A/B/D/J Programming Codes
Service Guide
•
•
•
•
•
Troubleshooting
Replaceable Parts
Assembly Replacement
Post- Repair Procedures
Safety and Regulatory
Key and Data Field
Reference
Volume 1:
• Symbols, Numerics, A- H
Volume 2:
• Volume 2: I- Z
xxiv
1
E4428C Analog Signal Generator Overview
The following list shows the topics covered in this chapter:
•
“Standard Analog Signal Generator Features” on page 2
•
“Options” on page 3
•
“Firmware Upgrades” on page 3
•
“Calibration” on page 4
•
“Modes of Operation” on page 5
•
“Front Panel Overview” on page 6
•
“Front Panel Display” on page 12
•
“Rear Panel Overview” on page 16
1
E4428C Analog Signal Generator Overview
Standard Analog Signal Generator Features
Standard Analog Signal Generator Features
•
CW output from 250 kHz to 3 or 6 GHz; the high-end frequency is dependent on the frequency option
purchased with your signal generator
•
list and step sweep of frequency and amplitude, with multiple trigger sources
•
user flatness correction
•
automatic leveling control (ALC) on and off modes; power calibration in ALC-off mode is available,
even without power search
•
10 MHz reference oscillator with external output
•
GPIB, RS-232, and 10Base-T LAN interfaces
•
closed-loop AM
•
dc-synthesized FM to 10 MHz rates; maximum deviation depends on the carrier frequency
•
phase modulation
•
pulse modulation
•
a function generator that includes the following features:
—
—
—
—
•
50Ω low frequency output, 0 to 3 Vp
selectable waveforms: sine, square, ramp, triangle, noise, swept-sine, dual-sine, and pulse
variable frequency modulation rates
variable triggering in list and step sweep modes: auto, external, single, or remote
a pulse generator that includes the following features:
— external pulse
— internal square wave
— internal pulse sources: internal square, internal pulse, external 1 dc-coupled, and external 2
dc-coupled
— adjustable pulse width
— adjustable pulse period
— adjustable pulse rate
•
external modulation inputs for AM, FM, and ΦM
•
simultaneous modulation configurations
2
Chapter 1
E4428C Analog Signal Generator Overview
Options
Options
ESG signal generators have hardware, firmware, software, and documentation options. The data sheet
shipped with your signal generator provides an overview of available options. For more information, visit
the Agilent ESG web page at http://www.agilent.com/find/esg, selected the desired ESG model, and then
click the Options tab.
Firmware Upgrades
You can upgrade the firmware in your signal generator whenever new firmware is released. New firmware
releases, which can be downloaded from the Agilent website, may contain signal generator features and
functionality not available in previous firmware releases.
To determine the availability of new signal generator firmware, visit the Signal Generator Firmware
Upgrade Center web page at http://www.agilent.com/find/upgradeassistant, or call the number listed at
http://www.agilent.com/find/assist.
To Upgrade Firmware
The following procedure shows you how to download new firmware to your ESG using a LAN connection
and a PC. For information on equipment requirements and alternate methods of downloading firmware, such
as GPIB, refer to the Firmware Upgrade Guide, which can be accessed at
http://www.agilent.com/find/upgradeassistant.
1. Note the IP address of your signal generator. To view the IP address on the ESG, press Utility >
GPIB/RS-232 LAN > LAN Setup.
2. Use an internet browser to visit http://www.agilent.com/find/upgradeassistant.
3. Scroll down to the “Documents and Downloads” table and click the link in the “Latest Firmware
Revision” column for the E4428C/38C ESG.
4. In the File Download window, select Run.
5. In the Welcome window, click Next and follow the on-screen instructions. The firmware files download
to the PC.
6. In the “Documents and Downloads” table, click the link in the “Upgrade Assistant Software” column for
the E4428C/38C ESG to download the PSG/ESG Upgrade Assistant.
7. In the File Download window, select Run.
8. In the Welcome window, click OK and follow the on-screen instructions.
Chapter 1
3
E4428C Analog Signal Generator Overview
Calibration
9. At the desktop shortcut prompt, click Yes.
10. Once the utility downloads, close the browser and double-click the PSG/ESG Upgrade Assistant icon on the
desktop.
11. In the upgrade assistant, set the connection type you wish to use to download the firmware, and the
parameters for the type of connection selected. For LAN, enter the instrument’s IP address, which you
recorded in step 1.
NOTE
If the PSG’s dynamic host configuration protocol (DHCP) is enabled, the network assigns
the instrument an IP address at power on. Because of this, when DHCP is enabled, the IP
address may be different each time you turn on the instrument. DHCP does not affect the
hostname.
12. Click Browse, and double-click the firmware revision to upgrade your signal generator.
13. In the Upgrade Assistant, click Next.
14. Once connection to the instrument is verified, click Next and follow the on-screen prompts.
NOTE
Once the download starts, it cannot be aborted.
NOTE
When the User Attention message appears, you must first cycle the instrument’s power,
then click OK.
When the upgrade completes, the Upgrade Assistant displays a summary.
15. Click OK and close the Upgrade Assistant.
Calibration
Agilent Technologies recommends calibrating the E4428C ESG Signal Generator every two years.
4
Chapter 1
E4428C Analog Signal Generator Overview
Modes of Operation
Modes of Operation
The ESG signal generator provides three modes of operation:
•
•
•
continuous wave (CW)
swept signal
analog modulation
Continuous Wave
In this mode, the signal generator produces a CW signal. The signal generator is set to a single frequency
and power level.
Swept Signal
In this mode, the signal generator sweeps over a range of frequencies and/or power levels. Both list and step
sweep functionality is available.
Analog Modulation
In this mode, the signal generator modulates the CW signal using one of four analog modulation types:
•
•
•
•
AM (two paths)
FM (two paths)
ΦM (normal and high bandwidth)
Pulse modulation
Chapter 1
5
E4428C Analog Signal Generator Overview
Front Panel Overview
Front Panel Overview
Figure 1-1 shows the signal generator front panel. This interface enables you to define, monitor, and manage
input and output characteristics.
Figure 1-1
Front Panel Feature Overview
1. Display
The LCD screen provides information on the current function. Information can include status indicators,
frequency and amplitude settings, and error messages. Labels for the softkeys are located on the right-hand
side of the display. For further description of the front panel display, refer to “Front Panel Display” on page
12.
2. Softkeys
Softkeys activate the function indicated by the displayed label to the left of each key.
6
Chapter 1
E4428C Analog Signal Generator Overview
Front Panel Overview
3. Frequency Key
Pressing this hardkey makes frequency the active function. You can change the RF output frequency or use
the menus to configure frequency attributes such as frequency multiplier, offset, and reference.
4. Amplitude Key
Pressing this hardkey activates the amplitude function. You can change the RF output amplitude or use the
menus to configure amplitude attributes such as power search, user flatness, and ALC BW.
5. Knob
Rotating the knob increases or decreases a numeric value or changes a highlighted digit or character. You
can also use the knob to step through lists or select items in a row. The knob uses the Incr Set value in
conjunction with the knob ratio (set with the Step/Knob Ratio softkey) to determine how much each turn of
the knob changes the active function value. For example, if the Incr Set value for the active function is 10 dB
and the knob ratio is 50 to 1, then each turn of the knob changes the active function by 0.2 dB (1/50th of
10 dB). By modifying either value or both, you change the amount for each turn of the knob. For more
information on softkeys, refer to the E4428C/38C ESG Signal Generators Key and Data Field Reference.
7. Save Key
This hardkey accesses a menu of softkeys enabling you to save data to the signal generator’s instrument state
memory register. The instrument state register is a section of memory divided into 10 sequences numbered 0
through 9. Each sequence contains 100 registers numbered 00 through 99.
The Save hardkey provides a quick alternative to reconfiguring the signal generator via the front panel or
with SCPI commands when switching between different configurations. The Recall hardkey recalls a saved
instrument state.
Refer to “Saving an Instrument State” on page 71 for more information on the save operation.
7. Menu Keys
These hardkeys access softkey menus enabling configuration of list and step sweeps, utility functions, the
LF output, and various analog modulation types. For detailed information on these keys, refer to the
E4428C/38C ESG Signal Generators Key and Data Field Reference.
8. Recall Key
This hardkey restores any instrument state that you previously saved in a instrument state memory register.
Chapter 1
7
E4428C Analog Signal Generator Overview
Front Panel Overview
9. EXT 1 INPUT Connector
This BNC input connector accepts an input signal for use with AM, FM, ΦM, and pulse modulation. The
damage levels are 5 Vrms and 10 Vp.
AM, FM, ΦM
±1 Vp produces the indicated deviation or depth. When using the AC coupled input selection with a signal that
has a peak input voltage that differs from 1 Vp by more than 3%, the signal generator displays HI/LO annunciator.
Pulse Modulation
+1 V is on and 0 V is off
On signal generators with Option 1EM, this input is relocated to a female BNC connector on the rear panel.
10. EXT 2 INPUT Connector
This BNC input connector accepts an input signal for use with AM, FM, ΦM, and pulse modulation. The
damage levels are 5 Vrms and 10 Vp.
AM, FM, ΦM
±1 Vp produces the indicated deviation or depth. When using the AC coupled input selection with a signal that
has a peak input voltage that differs from 1 Vp by more than 3%, the signal generator displays HI/LO annunciator.
Pulse Modulation
+1 V is on and 0 V is off
On signal generators with Option 1EM, this input is relocated to a female BNC connector on the rear panel.
11. Help Key
Press this key to display a short description of any hardkey or softkey. There are two help modes available:
single and continuous. Single mode is the factory preset condition. To toggle between single and continuous
mode, press Utility > Instrument Info/Help Mode > Help Mode Single Cont.
Single Mode
The help text is provided for the next key you press without activating the key’s function. Any key pressed
afterward exits the help mode and activates the key’s function
Continuous Mode The help text is provided for each subsequent key press until you either press the Help key again, or change to
single mode. In continuous mode, pressing the Help key also activates the key’s function (except for the Preset key).
12. Trigger Key
This hardkey initiates an immediate trigger event for a function such as a list or step sweep. The trigger
mode must be set to Trigger Key prior to initiating a trigger event with this hardkey.
13. LF OUTPUT Connector
This BNC connector is the output for modulation signals generated by the low frequency (LF) source
function generator. This output is capable of driving 3 Vp (nominal) into a 50Ω load.
On signal generators with Option 1EM, this output is relocated to a rear-panel female BNC connector.
8
Chapter 1
E4428C Analog Signal Generator Overview
Front Panel Overview
14. RF OUTPUT Connector
This female Type-N connector is the output for RF signals. The source impedance is 50Ω. For Options 501,
502, 503, and 504 the damage levels are 50 Vdc, 50 W at ≤ 2 GHz, and 25 W at > 2 GHz maximum. For
Options 501, 502, 503, and 504 the reverse power protection circuit will trip, however, at nominally 1 W.
CAUTION
E4428C and E4438C signal generators with Option 506 are not equipped with reverse
power protection circuits.
On signal generators with Option 1EM, this output is relocated to a rear-panel female Type-N connector.
15. Mod On/Off Key
Pressing this hardkey enables or disables all active modulation formats (AM, FM, ΦM, or Pulse) that are
applied to the output carrier signal.
This hardkey does not set up or activate an AM, FM, ΦM, or Pulse format; each individual modulation
format must still be set up and activated (for example, AM > AM On) or nothing will be applied to the output
carrier signal when the Mod On/Off hardkey is enabled.
The MOD ON/OFF annunciator, which is always present on the display, indicates whether active modulation
formats have been enabled or disabled with the Mod On/Off hardkey.
16. RF On/Off Key
This hardkey toggles the operating state of the RF signal present at the RF OUTPUT connector. The
RF On/Off annunciator is always visible in the display to indicate whether the RF is turned on or off.
17. Numeric Keypad
The numeric keypad consists of the 0 through 9 hardkeys, a decimal point hardkey, and a backspace hardkey
(
). The backspace hardkey enables you to backspace or specify a negative value. When specifying a
negative numeric value, the negative sign must be entered prior to entering the numeric value.
18. Incr Set Key
This hardkey enables you to set the increment value of the current active function. When this hardkey is
pressed, the increment value of the current active function appears as the active entry for the display. Use the
numeric keypad, arrow hardkeys, or the knob to adjust the increment value. Changing the Incr Set hardkey’s
value also affects how much each turn of the knob changes an active function’s value according to the
knob’s current ratio setting. For more information on softkeys, refer to the E4428C/38C ESG Signal
Generators Key and Data Field Reference.
Chapter 1
9
E4428C Analog Signal Generator Overview
Front Panel Overview
19. Arrow Keys
The up and down arrow hardkeys are used to increase or decrease a numeric value, step through displayed
lists, or select items in a row of a displayed list. Individual digits or characters may be highlighted using the
left and right arrow hardkeys. Once an individual digit or character is highlighted, its value can be changed
using the up and down arrow hardkeys.
20. Hold Key
This hardkey blanks the softkey label area, the active function area, and the text areas of the display.
Softkeys, arrow hardkeys, the knob, the numeric keypad, and the Incr Set hardkey have no effect once this
hardkey is pressed. Press any other hardkey to end the hold mode.
21. Return Key
This hardkey enables you to retrace your key presses. When in a menu with more than one level (More 1 of
3, More 2 of 3, etc.), the Return key will always return you to the first level of the menu.
22. Display Contrast Increase Key
This hardkey, when pressed or held, causes the display background to darken.
23. Display Contrast Decrease Key
This hardkey, when pressed or held, causes the display background to lighten.
24. Local Key
This hardkey is used to deactivate remote operation and return the signal generator to front panel control.
25. Preset Key
This hardkey is used to set the signal generator to a known state (factory or user-defined).
26. Standby LED
This yellow LED indicates when the signal generator power switch is set to the standby condition.
27. Line Power LED
This green LED indicates when the signal generator power switch is set to the on position.
10
Chapter 1
E4428C Analog Signal Generator Overview
Front Panel Overview
28. Power Switch
This switch activates full power to the signal generator when set to the on position, and deactivates all signal
generator functions when in standby mode. In standby mode, the signal generator remains connected to the
line power, and power is supplied to some internal circuits.
Chapter 1
11
E4428C Analog Signal Generator Overview
Front Panel Display
Front Panel Display
Figure 1-2 shows the front panel display. The LCD screen displays data fields, annotations, key press results,
softkey labels, error messages, and annunciators that represent various active functions.
Figure 1-2
Front Panel Display
1. Frequency Area
The current frequency setting is shown in this portion of the display. In this same area, the ESG displays the
indicators for frequency offset (OFFS) and multiplier (MULT) functions. In addition, REF appears when you
enable the frequency reference mode and CHANNEL is turned on when you turn on a frequency channel
(Freq Channels Off On softkey).
12
Chapter 1
E4428C Analog Signal Generator Overview
Front Panel Display
2. Annunciators
The display annunciators show the status of some of the signal generator functions, and indicate error
conditions. An annunciator position may be used by more than one function. This does not create a problem,
because only one function that shares an annunciator position can be active at a given time.
ΦM
This annunciator appears when phase modulation is turned on. If frequency modulation
is turned on, the FM annunciator will replace ΦM.
ALC OFF
This annunciator appears when the ALC circuit is disabled. A second annunciator,
UNLEVEL, will appear in the same position if the ALC is enabled and is unable to
maintain the output level.
AM
This annunciator appears when amplitude modulation is turned on.
ARMED
This annunciator appears when a sweep has been initiated and the signal generator is
waiting for the sweep trigger event.
ATTEN HOLD
This annunciator appears when the attenuator hold function is turned on. When this
function is on, the attenuator is held at its current setting.
ERR
This annunciator appears when an error message is placed in the error queue. This
annunciator will not turn off until you have viewed all of the error messages or cleared
the error queue. You can access error messages by pressing Utility > Error Info.
EXT1 LO/HI
This annunciator is displayed as either EXT1 LO or EXT1 HI. This annunciator appears
when the ac-coupled signal to the EXT 1 INPUT is less than 0.97 Vp or greater than
1.03 Vp.
EXT2 LO/HI
This annunciator is displayed as either EXT2 LO or EXT2 HI. This annunciator appears
when the ac-coupled signal to the EXT 2 INPUT is less than 0.97 Vp or greater than
1.03 Vp.
EXT REF
This annunciator appears when an external frequency reference is applied.
FM
This annunciator appears when frequency modulation is turned on. If phase modulation
is turned on, the ΦM annunciator will replace FM.
L
This annunciator appears when the signal generator is in listener mode and is receiving
information or commands over the GPIB, RS-232, or VXI-11/Sockets (LAN) interface.
Chapter 1
13
E4428C Analog Signal Generator Overview
Front Panel Display
MOD ON/OFF
This annunciator indicates if the RF carrier is modulated (MOD ON while there is an
active modulation format), or if the modulation is off (MOD OFF). Either condition of
this annunciator is always visible in the display.
The MOD ON annunciator may be showing even when there are no active modulation
formats. This merely indicates that the carrier signal will be modulated when a
modulation format is enabled.
OVEN COLD
This annunciator appears when the temperature of the internal oven reference oscillator
has dropped below an acceptable level. When this annunciator is on, frequency
accuracy is degraded. This condition should occur for several minutes after the signal
generator is first connected to line power. The annunciator is timed, and automatically
turns off after a specified period.
PULSE
This annunciator appears when pulse modulation is turned on.
R
This annunciator appears when the signal generator is remotely controlled over the
GPIB, RS-232, or VXI-11/Sockets (LAN) interface.
RF ON/OFF
This annunciator indicates when the RF signal is present (RF ON) at the RF OUTPUT,
or if the RF signal is not present (RF OFF) at the RF OUTPUT. Either condition of this
annunciator is always visible in the display.
S
This annunciator appears when the signal generator has generated a service request
(SRQ) over the GPIB, RS-232, or VXI-11/Sockets (LAN) interface.
SWEEP
This annunciator appears when the signal generator is sweeping in list or step mode.
T
This annunciator appears when the signal generator is in talker mode and is transmitting
information over the GPIB, RS-232, or VXI-11/Sockets (LAN) interface.
UNLEVEL
This annunciator appears when the signal generator is unable to maintain the correct
output level. The UNLEVEL annunciator is not necessarily an indication of instrument
failure. Unleveled conditions can occur during normal operation. A second annunciator,
ALC OFF, will appear in the same position when the ALC circuit is disabled.
UNLOCK
This annunciator appears when any of the phase locked loops are unable to maintain
phase lock. You can determine which loop is unlocked by examining the error
messages.
14
Chapter 1
E4428C Analog Signal Generator Overview
Front Panel Display
3. Amplitude Area
The current output power level setting is shown in this portion of the display. When active, the following
functions also display indicators in the amplitude area:
•
•
•
•
Amplitude offset (OFFS)
Amplitude reference mode (REF)
Alternate Amplitude (Δ = 0.00 dB)
User flatness (UF)
4. Softkey Label Area
The labels in this area define the function of the softkeys located immediately to the right of the label. The
softkey label will change depending upon the function selected. For detailed softkey descriptions, refer to
the E4428C/38C ESG Signal Generators Key and Data Field Reference.
5. Error Message Area
Abbreviated error messages are reported in this space. When multiple error messages occur, only the most
recent message remains displayed. Reported error messages with details can be viewed by pressing
Utility > Error Info.
6. Text Area
This area of the display is used to show status information about the signal generator such as the modulation
status, sweep lists, and file catalogs. This area also enables you to perform functions such as managing
information, entering information, and displaying or deleting files.
7. Active Function Area
The current active function is shown in this area. For example, if frequency is the active function, the current
frequency setting will be displayed here. If the current active function has an increment value associated
with it, that value is also displayed.
Chapter 1
15
E4428C Analog Signal Generator Overview
Rear Panel Overview
Rear Panel Overview
The signal generator rear panel (Figure 1-3) provides input, output, and remote interface connections.
Figure 1-4 shows a portion of the rear panel for signal generators with Option 1EM, which moves front
panel connectors to the rear panel. For Option 1EM connectors not described in this section, see
“Front Panel Overview” on page 6.
Figure 1-3
Rear Panel Feature Overview
Figure 1-4
16
Chapter 1
E4428C Analog Signal Generator Overview
Rear Panel Overview
1. AC Power Receptacle
The power cord receptacle accepts a three-pronged cable that is shipped with the signal generator. The line
voltage is connected here.
2. GPIB Connector
The GPIB connector allows communications with compatible devices such as external controllers. It is
functionally equivalent to the LAN and RS 232 connectors.
3. RS 232 Connector
This female DB-9 connector is an RS-232 serial port that can be used for controlling the signal generator
remotely. It is functionally equivalent to the GPIB and LAN connectors. The following table shows the
description of the pinouts. Figure 1-5 shows the pin configuration.
Table 1-1
RS 232 Connector
Pin Number
Signal Description
Signal Name
1
No Connection
2
Receive Data
RECV
3
Transmit Data
XMIT
4
+5 V
5
Ground, 0 V
6
No Connection
7
Request to Send
RTS
8
Clear to Send
CTS
9
No Connection
Figure 1-5
View looking into
rear panel connector
Chapter 1
17
E4428C Analog Signal Generator Overview
Rear Panel Overview
4. LAN Connector
LAN based communication is supported by the signal generator via the LAN (local area network) connector.
The LAN connector enables the signal generator to be remotely programmed by a LAN-connected
computer. The distance between a computer and the signal generator is limited to 100 meters (10Base-T) on
a single cable. For more information about the LAN, refer to the E4428C/38C ESG Signal Generators
Programming Guide.
5. TRIG OUT Connector
This female BNC connector outputs a TTL signal that is asserted high at the start of a dwell sequence, or at
the start of waiting for the point trigger in manual sweep mode. It is asserted low when the dwell is over,
when the point trigger is received, or once per sweep during an LF sweep. The logic polarity can be
reversed.
6. TRIG IN Connector
This female BNC connector accepts a CMOS signal for triggering operations, such as point-to-point in
manual sweep mode or an LF sweep in external sweep mode. Triggering can occur on either the positive or
negative edge. The damage levels are > +5.5 volts and < −0.5 volts.
7. 10 MHz IN Connector
This female BNC connector accepts a −3.5 to +20 dBm signal from an external timebase reference that is 1,
2, 5, or 10 MHz ±0.2 ppm. The nominal input impedance is 50Ω. The signal generator detects when a valid
reference signal is present at this connector and automatically switches from internal to external reference
operation. The signal generator will only automatically switch from internal to external reference operation
when the instrument is in its factory default mode where the Ref Oscillator Source Auto Off On softkey is set to
on.
8. SWEEP OUT Connector
This female BNC connector provides a voltage range of 0 to +10 V. When the signal generator is sweeping,
the SWEEP OUT signal ranges from 0 V at the beginning of the sweep to +10 V at the end of the sweep
regardless of the sweep width. In CW mode this connector has no output. The output impedance is less than
1Ω and can drive 2 kΩ.
9. 10 MHz OUT Connector
This female BNC connector provides a nominal signal level of +3.9 dBm ±2 dB, and an output impedance
of 50Ω. The accuracy is determined by the timebase used.
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Chapter 1
2
E4438C Vector Signal Generator Overview
The following list shows the topics covered in this chapter:
•
“Standard Vector Signal Generator Features” on page 20
•
“Options” on page 21
•
“Firmware Upgrades” on page 22
•
“Calibration” on page 23
•
“Modes of Operation” on page 24
•
“Front Panel Overview” on page 26
•
“Front Panel Display” on page 33
•
“Rear Panel Overview” on page 37
19
E4438C Vector Signal Generator Overview
Standard Vector Signal Generator Features
Standard Vector Signal Generator Features
•
CW output from 250 kHz to 1, 2, 3, 4 or 6 GHz; the high-end frequency is dependent on the frequency
option purchased with your signal generator
•
list and step sweep of frequency and amplitude, with multiple trigger sources
•
user flatness correction
•
automatic leveling control (ALC) on and off modes; power calibration in ALC-off mode is available,
even without power search
•
10 MHz reference oscillator with external output
•
GPIB, RS-232, and 10Base-T LAN interfaces
•
closed-loop AM
•
dc-synthesized FM to 10 MHz rates; maximum deviation depends on the carrier frequency
•
phase modulation
•
pulse modulation
•
a function generator that includes the following features:
—
—
—
—
•
50Ω low frequency output, 0 to 3 Vp
selectable waveforms: sine, square, ramp, triangle, noise, swept-sine, dual-sine, and pulse
variable frequency modulation rates
variable triggering in list and step sweep modes: auto, external, single, or remote
a pulse generator that includes the following features:
— external pulse
— internal square wave
— internal pulse sources: internal square, internal pulse, external 1 dc-coupled, and external 2
dc-coupled
— adjustable pulse width
— adjustable pulse period
— adjustable pulse rate
•
external modulation inputs for AM, FM, ΦM, and I/Q modulation
•
simultaneous modulation configurations
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E4438C Vector Signal Generator Overview
Options
Options
ESG signal generators have hardware, firmware, software, and documentation options. The data sheet
shipped with your signal generator provides an overview of available options. For more information, visit
the Agilent ESG web page at http://www.agilent.com/find/esg, selected the desired ESG model, and then
click the Options tab.
Understanding Baseband Generator Options
Your E4438C can have one of four baseband generator options, depending upon when you first purchased
the instrument and whether or not the baseband generator has been upgraded to a newer version. The options
consist of the following:
Option 001
internal baseband generator with 8 megasample memory (no longer available)
Option 002
internal baseband generator with 32 megasample memory (no longer available)
Option 601
internal baseband generator with 8 megasample memory and digital bus capability
Option 602
internal baseband generator with 64 megasample memory and digital bus capability
These four baseband generators are similar in some respects, and very different in others. They are similar in
that all four versions support the same signal generation formats, such as W-CDMA, cdma2000, WLAN,
and many others. All four versions offer both arbitrary waveform capability and real-time baseband
generation capability.
The first obvious difference between these four baseband generators is that they offer different playback
memory sizes. This is primarily important to users providing their own arbitrary waveform files, since these
may be very large in size. Of the signal creation personalities offered by Agilent, currently only Signal
Studio for WLAN and Signal Studio for Pulse Building are capable of creating waveforms that can exceed
the 8 megasample memory of the Option 001/601 models.
The second important difference between these baseband generators is that only Option 601 and 602 offer
digital bus capability. This proprietary digital bus is used for communication with the Agilent Baseband
Studio suite of products. Baseband Studio products provide a range of baseband signal processing functions,
including baseband digital outputs, fading, and hard drive waveform streaming. These functions are not
compatible with Options 001 or 002. An upgrade kit is available, however, if you want to add Option 601 or
602 to your existing E4438C ESG.
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E4438C Vector Signal Generator Overview
Firmware Upgrades
Firmware Upgrades
You can upgrade the firmware in your signal generator whenever new firmware is released. New firmware
releases, which can be downloaded from the Agilent website, may contain signal generator features and
functionality not available in previous firmware releases.
To determine the availability of new signal generator firmware, visit the Signal Generator Firmware
Upgrade Center web page at http://www.agilent.com/find/upgradeassistant, or call the number listed at
http://www.agilent.com/find/assist.
To Upgrade Firmware
The following procedure shows you how to download new firmware to your ESG using a LAN connection
and a PC. For information on equipment requirements and alternate methods of downloading firmware, such
as GPIB, refer to the Firmware Upgrade Guide, which can be accessed at
http://www.agilent.com/find/upgradeassistant.
1. Note the IP address of your signal generator. To view the IP address on the ESG, press Utility >
GPIB/RS-232 LAN > LAN Setup.
2. Use an internet browser to visit http://www.agilent.com/find/upgradeassistant.
3. Scroll down to the “Documents and Downloads” table and click the link in the “Latest Firmware
Revision” column for the E4428C/38C ESG.
4. In the File Download window, select Run.
5. In the Welcome window, click Next and follow the on-screen instructions. The firmware files download
to the PC.
6. In the “Documents and Downloads” table, click the link in the “Upgrade Assistant Software” column for
the E4428C/38C ESG to download the PSG/ESG Upgrade Assistant.
7. In the File Download window, select Run.
8. In the Welcome window, click OK and follow the on-screen instructions.
9. At the desktop shortcut prompt, click Yes.
10. Once the utility downloads, close the browser and double-click the PSG/ESG Upgrade Assistant icon on the
desktop.
11. In the upgrade assistant, set the connection type you wish to use to download the firmware, and the
parameters for the type of connection selected. For LAN, enter the instrument’s IP address, which you
recorded in step 1.
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E4438C Vector Signal Generator Overview
Calibration
NOTE
If the PSG’s dynamic host configuration protocol (DHCP) is enabled, the network assigns
the instrument an IP address at power on. Because of this, when DHCP is enabled, the IP
address may be different each time you turn on the instrument. DHCP does not affect the
hostname.
12. Click Browse, and double-click the firmware revision to upgrade your signal generator.
13. In the Upgrade Assistant, click Next.
14. Once connection to the instrument is verified, click Next and follow the on-screen prompts.
NOTE
Once the download starts, it cannot be aborted.
NOTE
When the User Attention message appears, you must first cycle the instrument’s power,
then click OK.
When the upgrade completes, the Upgrade Assistant displays a summary.
15. Click OK and close the Upgrade Assistant.
Calibration
Agilent Technologies recommends calibrating the E4438C ESG Signal Generator every two years.
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E4438C Vector Signal Generator Overview
Modes of Operation
Modes of Operation
The ESG signal generator provides four modes of operation:
•
•
•
•
continuous wave (CW)
swept signal
analog modulation
digital modulation
Continuous Wave
In this mode, the signal generator produces a CW signal. The signal generator is set to a single frequency
and power level.
Swept Signal
In this mode, the signal generator sweeps over a range of frequencies and/or power levels. Both list and step
sweep functionality is available.
Analog Modulation
In this mode, the signal generator modulates the CW signal using one of four analog modulation types:
•
•
•
•
AM (two paths and wideband)
FM (two paths)
ΦM (normal and high bandwidth)
Pulse modulation
Some of these modulation types can be used together.
Digital Modulation
In this mode, the signal generator modulates a CW signal with either a real-time I/Q signal or arbitrary I/Q
waveform. I/Q modulation is only available on the E4438C. An optional internal baseband generator
(Option 001/601 002/602) adds the following digital modulation formats:
•
24
Custom Arb Waveform Generator mode can produce a single-modulated carrier or multiple-modulated
carriers. Each modulated carrier waveform must be calculated and generated before it can be output; this
signal generation occurs on the internal baseband generator. Once a waveform has been created, it can be
stored and recalled, which enables repeatable playback of test signals. To learn more, refer to “Using the
Arbitrary Waveform Generator” on page 384.
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E4438C Vector Signal Generator Overview
Modes of Operation
•
Custom Real Time I/Q Baseband mode produces a single carrier, but it can be modulated with real-time
data that allows real-time control over all of the parameters that affect the signal. The single-carrier
signal that is produced can be modified by applying various data patterns, filters, symbol rates,
modulation types, and burst shapes. To learn more, refer to “Using the Real Time I/Q Baseband
Generator” on page 390.
•
Multitone mode produces up to 64 continuous wave signals (or tones) with adjustable amplitude and
frequency spacing. To learn more, refer to “Multitone Waveform Generator (Options 001/601 or
002/602)” on page 377.
•
Dual ARB mode is used to control the playback sequence of waveform segments that have been written
into the ARB memory located on the internal baseband generator. These waveforms can be generated by
the internal baseband generator using any of the Arb modulation formats, or downloaded through a
remote interface into the ARB memory. To learn more, refer to “Using the Dual ARB Waveform Player”
on page 107.
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E4438C Vector Signal Generator Overview
Front Panel Overview
Front Panel Overview
Figure 2-1 shows the signal generator front panel. This interface enables you to define, monitor, and manage
input and output characteristics.
Figure 2-1
Front Panel Feature Overview
1. Display
The LCD screen provides information on the current function. Information can include status indicators,
frequency and amplitude settings, and error messages. Labels for the softkeys are located on the right-hand
side of the display. For further description of the front panel display, refer to “Front Panel Display” on page
33.
2. Softkeys
Softkeys activate the function indicated by the displayed label to the left of each key.
3. Frequency Key
Pressing this hardkey makes frequency the active function. You can change the RF output frequency or use
the menus to configure frequency attributes such as frequency multiplier, offset, and reference.
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Front Panel Overview
4. Amplitude Key
Pressing this hardkey activates the amplitude function.
When active, the following functions also display indicators in the amplitude area:
•Amplitude offset (OFFS)
•Amplitude reference mode (REF)
•Alternate Amplitude (Δ = 0.00 dB)
•User flatness (UF)
5. Knob
Rotating the knob increases or decreases a numeric value or changes a highlighted digit or character. You
can also use the knob to step through lists or select items in a row. The knob uses the Incr Set value in
conjunction with the knob ratio (set with the Step/Knob Ratio softkey) to determine how much each turn of
the knob changes the active function value. For example, if the Incr Set value for the active function is 10 dB
and the knob ratio is 50 to 1, then each turn of the knob changes the active function by 0.2 dB (1/50th of
10 dB). By modifying either value or both, you change the amount for each turn of the knob. For more
information on softkeys, refer to the E4428C/38C ESG Signal Generators Key and Data Field Reference.
6. Menu Keys
These hardkeys access softkey menus enabling configuration of list and step sweeps, utility functions, the
LF output, and various analog and digital modulation types. For detailed information on these keys, refer to
the E4428C/38C ESG Signal Generators Key and Data Field Reference.
7. Save Key
This hardkey accesses a menu of softkeys enabling you to save instrument settings to the signal generator’s
instrument state memory register. The instrument state register is a section of memory divided into 10
sequences numbered 0 through 9. Each sequence contains 100 registers numbered 00 through 99.
The Save hardkey provides a quick alternative to reconfiguring the signal generator via the front panel. The
Recall hardkey recalls a saved instrument state.
Refer to “Saving an Instrument State” on page 71 for more information on the save operation.
8. Recall Key
This hardkey restores any instrument state that you previously saved in a instrument state memory
register.When you load the waveform file from NVWFM into waveform memory (WFM1), and then use the
Recall softkey to recall the signal generator settings associated with the file.
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E4438C Vector Signal Generator Overview
Front Panel Overview
9. EXT 1 INPUT Connector
This BNC input connector accepts an input signal for use with AM, FM, ΦM, and pulse modulation, or as
the linear control for a burst envelope. The damage levels are 5 Vrms and 10 Vp.
AM, FM, ΦM
±1 Vp produces the indicated deviation or depth. When using the AC coupled input selection with a
signal that has a peak input voltage that differs from 1 Vp by more than 3%, the signal generator
displays the HI/LO annunciator.
Pulse Modulation
+1 V is on and 0 V is off
Burst Envelope
Provides linear control: −1 V = 0% amplitude and 0 V = 100% amplitude
On signal generators with Option 1EM, this input is relocated to an SMB connector on the rear panel.
10. EXT 2 INPUT Connector
This BNC input connector accepts an input signal for use with AM, FM, ΦM, and pulse modulation. The
damage levels are 5 Vrms and 10 Vp.
AM, FM, ΦM
±1 Vp produces the indicated deviation or depth. When using the AC coupled input selection with a
signal that has a peak input voltage that differs from 1 Vp by more than 3%, the signal generator
displays HI/LO annunciator.
Pulse Modulation +1 V is on and 0 V is off
If you configure your signal generator with Option 1EM, this input is relocated to an SMB connector on the
rear panel.
11. Help Key
Press this key to display a short description of any hardkey or softkey. There are two help modes available:
single and continuous. Single mode is the factory preset condition. To toggle between single and continuous
mode, press Utility > Instrument Info/Help Mode > Help Mode Single Cont.
Single Mode
The help text is provided for the next key you press without activating the key’s function. Any key
pressed afterward exits the help mode and activates the key’s function
Continuous Mode
The help text is provided for each subsequent key press until you either press the Help key again, or
change to single mode. In continuous mode, pressing the Help key also activates the key’s function
(except for the Preset key).
12. Trigger Key
This hardkey initiates an immediate trigger event for a function such as a list or step sweep. The trigger
mode must be set to Trigger Key prior to initiating a trigger event with this hardkey.
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E4438C Vector Signal Generator Overview
Front Panel Overview
13. LF OUTPUT Connector
This BNC connector is the output for modulation signals generated by the low frequency (LF) source
function generator. This output is capable of driving 3 Vp (nominal) into a 50Ω load.
On signal generators with Option 1EM, this output relocated to a rear-panel SMB connector.
14. RF OUTPUT Connector
This female Type-N connector is the output for RF signals. The source impedance is 50Ω. For Options 501,
502, 503, and 504 the damage levels are 50 Vdc, 50 W at ≤ 2 GHz, and 25 W at > 2 GHz maximum. For
Options 501, 502, 503, and 504 the reverse power protection circuit will trip, however, at nominally 1 W.
CAUTION
E4428C and E4438C signal generators with Option 506 are not equipped with reverse
power protection circuits.
On signal generators with Option 1EM, this output relocated to a rear-panel female Type-N connector.
15. Mod On/Off Key
Pressing this hardkey enables or disables all active modulation formats (AM, FM, ΦM, Pulse, or I/Q) that
are applied to the output carrier signal.
This hardkey does not set up or activate an AM, FM, ΦM, Pulse, or I/Q format; each individual modulation
format must still be set up and activated (for example, AM > AM On) or nothing will be applied to the output
carrier signal when the Mod On/Off hardkey is enabled.
The MOD ON/OFF annunciator, which is always present on the display, indicates whether active modulation
formats have been enabled or disabled with the Mod On/Off hardkey.
16. RF On/Off Key
This hardkey toggles the operating state of the RF signal present at the RF OUTPUT connector. The
RF On/Off annunciator is always visible in the display to indicate whether the RF is turned on or off.
17. Numeric Keypad
The numeric keypad consists of the 0 through 9 hardkeys, a decimal point hardkey, and a backspace hardkey
(
). The backspace hardkey enables you to backspace or specify a negative value. When specifying a
negative numeric value, the negative sign must be entered prior to entering the numeric value.
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E4438C Vector Signal Generator Overview
Front Panel Overview
18. Incr Set Key
This hardkey enables you to set the increment value of the current active function. When this hardkey is
pressed, the increment value of the current active function appears as the active entry for the display. Use the
numeric keypad, arrow hardkeys, or the knob to adjust the increment value. Changing the Incr Set hardkey’s
value also affects how much each turn of the knob changes an active function’s value according to the
knob’s current ratio setting. For more information on softkeys, refer to the E4428C/38C ESG Signal
Generators Key and Data Field Reference.
19. Arrow Keys
The up and down arrow hardkeys are used to increase or decrease a numeric value, step through displayed
lists, or select items in a row of a displayed list. Individual digits or characters may be highlighted using the
left and right arrow hardkeys. Once an individual digit or character is highlighted, its value can be changed
using the up and down arrow hardkeys.
20. Hold Key
This hardkey blanks the softkey label area, the active function area, and the text areas of the display.
Softkeys, arrow hardkeys, the knob, the numeric keypad, and the Incr Set hardkey have no effect once this
hardkey is pressed. Press any other hardkey to end the hold mode.
21. Return Key
This hardkey enables you to retrace your key presses. When in a menu with more than one level (More 1 of
3, More 2 of 3, etc.), the Return key will always return you to the first level of the menu.
22. Display Contrast Increase Key
This hardkey, when pressed or held, causes the display background to darken.
23. Display Contrast Decrease Key
This hardkey, when pressed or held, causes the display background to lighten.
24. Local Key
This hardkey is used to deactivate remote operation and return the signal generator to front panel control.
25. Preset Key
This hardkey is used to set the signal generator to a known state (factory or user-defined).
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E4438C Vector Signal Generator Overview
Front Panel Overview
26. Standby LED
This yellow LED indicates when the signal generator power switch is set to the standby condition.
27. Line Power LED
This green LED indicates when the signal generator power switch is set to the on position.
28. Power Switch
This switch activates full power to the signal generator when set to the on position, and deactivates all signal
generator functions when in standby mode. In standby mode, the signal generator remains connected to the
line power, and power is supplied to some internal circuits.
29. SYMBOL SYNC Connector (Option 001/601 or 002/602)
This female BNC input connector accepts an externally supplied symbol sync signal for use with digital
modulation applications. The expected input is a CMOS bit clock signal. It may be used in two modes.
When used as a symbol sync in conjunction with a data clock, the signal must be high during the first data
bit of the symbol. The signal must be valid during the falling edge of the data clock signal and may be a
single pulse or continuous. When the SYMBOL SYNC itself is used as the (symbol) clock, the CMOS
falling edge is used to clock the DATA signal.
The maximum clock rate is 50 MHz. The damage levels are > +5.5 volts and < −0.5 volts.
On signal generators with Option 1EM, this input is relocated to a rear panel SMB connector.
When using the real-time W-CDMA uplink personality, this connector should not be used to connect the
external baseband generator data clock. The BASEBAND GEN REF IN connector should be used instead.
30. DATA CLOCK Connector (Option 001/601 or 002/602)
The female BNC input connector accepts a CMOS externally supplied CMOS compatible signal data-clock
input used with digital modulation applications. The expected input is a CMOS bit clock signal where the
rising edge is aligned with the beginning data bit. The falling edge is used to clock the DATA and SYMBOL
SYNC signals.
The maximum clock rate is 50 MHz. The damage levels are > +5.5 volts and < −0.5 volts.
On signal generators with Option 1EM, this input is relocated to a rear panel SMB connector.
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E4438C Vector Signal Generator Overview
Front Panel Overview
31. DATA Connector (Option 001/601 or 002/602)
The female BNC input connector accepts a CMOS externally supplied CMOS compatible signal data input
used with digital modulation applications. The expected input is a CMOS signal where a CMOS high is
equivalent to a data 1 and a CMOS low is equivalent to a data 0.
The maximum input data rate is 50 Mb/s.The data must be valid on the DATA CLOCK falling edges. The
damage levels are > +5.5 volts and < − 0.5 volts.
On signal generators with Option 1EM, this input is relocated to a rear panel SMB connector.
32. Q Connector
This female BNC input connector accepts an externally supplied, analog, quadrature-phase component of
I/Q modulation. The signal level is
= 0.5 Vrms for a calibrated output level. The input impedance is
50Ω. The damage level is 1 Vrms and 10 volts peak.
To activate a signal applied to this connector, press Mux > I/Q Source 1 or I/Q Source 2 and then select either
Ext 50 Ohm or Ext 600 Ohm. On signal generators with Option 1EM, this input is relocated as an SMB to the
rear panel.
33. I Connector
This female BNC input connector accepts an externally supplied, analog, in-phase component of I/Q
modulation. The signal level is
= 0.5 Vrms for a calibrated output level. The input impedance is 50Ω.
To activate the in-phase component of the I/Q signal applied to this connector, press Mux > I/Q Source 1 or
I/Q Source 2 and then select either Ext 50 Ohm or Ext 600 Ohm.
This input connector also accepts the modulating signal for use with the wideband AM selection. The
wideband AM signal depth is a linear function of the I INPUT signal voltage:
•
•
0.25 volts = 50%
0.5 volts = 100%
When turned on, wideband AM automatically selects the I INPUT and configures it for 50Ω. This setting is
independent of the MUX > I/Q Source setting.
The damage level for this connector is 1 Vrms and 10 volts peak. On signal generators with Option 1EM, this
input is relocated as an SMB to the rear panel.
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E4438C Vector Signal Generator Overview
Front Panel Display
Front Panel Display
Figure 2-2 shows the front panel display. The LCD screen displays data fields, annotations, key press results,
softkey labels, error messages, and annunciators that represent various active functions.
Figure 2-2
Front Panel Display
1. Frequency Area
The current frequency setting is shown in this portion of the display. In this same area, the ESG displays the
indicators for frequency offset (OFFS) and multiplier (MULT) functions. In addition, REF appears when you
enable the frequency reference mode and CHANNEL is turned on when you turn on a frequency channel
(Freq Channels Off On softkey).
Chapter 2
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E4438C Vector Signal Generator Overview
Front Panel Display
2. Annunciators
The display annunciators show the status of some of the signal generator functions, and indicate error
conditions. An annunciator position may be used by more than one function. This does not create a problem,
because only one function that shares an annunciator position can be active at a given time.
ΦM
This annunciator appears when phase modulation is turned on. If frequency modulation
is turned on, the FM annunciator will replace ΦM.
ALC OFF
This annunciator appears when the ALC circuit is disabled. Two other annunciators
appear in the same position: UNLEVEL when the ALC is enabled and is unable to
maintain the output level, and BBG DAC when the waveform data exceeds the DAC
range.
AM
This annunciator appears when amplitude modulation is turned on.
ARMED
This annunciator appears when a sweep has been initiated and the signal generator is
waiting for the sweep trigger event.
ATTEN HOLD
This annunciator appears when the attenuator hold function is turned on. When this
function is on, the attenuator is held at its current setting.
BERT
This annunciator appears when the Option UN7 bit error rate test (BERT) functions are
turned on.
ENVLP
This annunciator appears if the burst envelope modulation is turned on.
ERR
This annunciator appears when an error message is placed in the error queue. This
annunciator will not turn off until you have viewed all of the error messages or cleared
the error queue. You can access error messages by pressing Utility > Error Info.
EXT1 LO/HI
This annunciator is displayed as either EXT1 LO or EXT1 HI. This annunciator appears
when the ac-coupled signal to the EXT 1 INPUT is less than 0.97 Vp or greater than
1.03 Vp.
EXT2 LO/HI
This annunciator is displayed as either EXT2 LO or EXT2 HI. This annunciator appears
when the ac-coupled signal to the EXT 2 INPUT is less than 0.97 Vp or greater than
1.03 Vp.
EXT REF
This annunciator appears when an external frequency reference is applied.
FM
This annunciator appears when frequency modulation is turned on. If phase modulation
is turned on, the ΦM annunciator will replace FM.
L
This annunciator appears when the signal generator is in listener mode and is receiving
information or commands over the GPIB, RS-232, or VXI-11/Sockets (LAN) interface.
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Front Panel Display
MOD ON/OFF
This annunciator indicates if the RF carrier is modulated (MOD ON while there is an
active modulation format), or if the modulation is off (MOD OFF). Either condition of
this annunciator is always visible in the display.
The MOD ON annunciator may be showing even when there are no active modulation
formats. This merely indicates that the carrier signal will be modulated when a
modulation format is enabled.
OVEN COLD
This annunciator appears when the temperature of the internal oven reference oscillator
has dropped below an acceptable level. When this annunciator is on, frequency
accuracy is degraded. This condition should occur for several minutes after the signal
generator is first connected to line power. The annunciator is timed, and automatically
turns off after a specified period.
PULSE
This annunciator appears when pulse modulation is turned on.
R
This annunciator appears when the signal generator is remotely controlled over the
GPIB, RS-232, or VXI-11/Sockets (LAN) interface.
RF ON/OFF
This annunciator indicates when the RF signal is present (RF ON) at the RF OUTPUT,
or if the RF signal is not present (RF OFF) at the RF OUTPUT. Either condition of this
annunciator is always visible in the display.
S
This annunciator appears when the signal generator has generated a service request
(SRQ) over the GPIB, RS-232, or VXI-11/Sockets (LAN) interface.
SWEEP
This annunciator appears when the signal generator is sweeping in list or step mode.
T
This annunciator appears when the signal generator is in talker mode and is transmitting
information over the GPIB, RS-232, or VXI-11/Sockets (LAN) interface.
UNLEVEL
This annunciator appears when the signal generator is unable to maintain the correct
output level. The UNLEVEL annunciator is not necessarily an indication of instrument
failure. Unleveled conditions can occur during normal operation. Two other
annunciators appear in the same position: ALC OFF when the ALC circuit is disabled
and BBG DAC when the waveform data exceeds the DAC range.
BBG DAC
This annunciator appears when the waveform data exceeds the range of the DAC, which
causes a DAC over-range error. It remains illuminated until the condition is corrected by
scaling the data. It appears in the same location as the UNLEVEL and ALC OFF
annunciators, and is the dominant annunciator. For example, if an unleveled condition
exists at the same time as a DAC over-range condition, the DAC over-range annunciator
remains until corrected. Once corrected, the UNLEVEL annunciator appears.
UNLOCK
This annunciator appears when any of the phase locked loops are unable to maintain
phase lock. You can determine which loop is unlocked by examining the error
messages.
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E4438C Vector Signal Generator Overview
Front Panel Display
3. Digital Modulation Annunciators
All digital modulation annunciators appear in this location. These annunciators appear only when the
modulation is active, and only one digital modulation can be active at any given time.
4. Amplitude Area
The current output power level setting is shown in this portion of the display. When active, the following
functions also display indicators in the amplitude area:
•
•
•
•
Amplitude offset (OFFS)
Amplitude reference mode (REF)
Alternate Amplitude (Δ = 0.00 dB)
User flatness (UF)
5. Softkey Label Area
The labels in this area define the function of the softkeys located immediately to the right of the label. The
softkey label will change depending upon the function selected. For detailed softkey descriptions, refer to
the E4428C/38C ESG Signal Generators Key and Data Field Reference.
6. Error Message Area
Abbreviated error messages are reported in this space. When multiple error messages occur, only the most
recent message remains displayed. Reported error messages with details can be viewed by pressing Utility >
Error Info.
7. Text Area
This area of the display is used to show status information about the signal generator such as the modulation
status, sweep lists, and file catalogs. This area also enables you to perform functions such as managing
information, entering information, and displaying or deleting files.
8. Active Function Area
The current active function is shown in this area. For example, if frequency is the active function, the current
frequency setting will be displayed here. If the current active function has an increment value associated
with it, that value is also displayed.
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E4438C Vector Signal Generator Overview
Rear Panel Overview
Rear Panel Overview
The signal generator rear panel (Figure 2-3) provides input, output, and remote interface connections.
Figure 2-4 shows a portion of the rear panel for signal generators with Option 1EM, which moves front
panel connectors to the rear panel. For Option 1EM connectors not described in this section, see
“Front Panel Overview” on page 26.
Figure 2-3
Rear Panel Feature Overview
Figure 2-4
Chapter 2
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E4438C Vector Signal Generator Overview
Rear Panel Overview
1. 321.4 IN Connector (Option 300)
Use this female SMB connector to input a downconverted 321.4 MHz GSM/EDGE signal for base
transceiver station (BTS) loopback measurements. (Option 300 also requires Options UN7, 001/601or
002/602, and 402).
2. BER GATE IN Connector (Option UN7)
Use this female SMB connector to input the clock gate signal for the bit-error-rate measurements. The clock
signal to the BER CLK IN connector is valid only when the signal to this connector is a high or low,
depending on your softkey selection or SCPI command. The damage levels are > +5.5 volts and < −0.5 volts.
This connector accepts a high impedance TTL-compatible signal or a 75Ω input. It can be enabled or
disabled by a softkey or a SCPI command.
3. BER CLK IN Connector (Option UN7)
Use this female SMB connector to input the clock signal for the bit-error-rate measurements. The rising
(positive) or falling (negative) edge of the signal (selected either by softkey or SCPI command) causes data
on the BER DATA IN connector to be sampled. The damage levels are > +5.5 volts and < −0.5 volts. This
connector accepts a high impedance TTL-compatible signal or a 75Ω input.
4. BER DATA IN Connector (Option UN7)
Use this female SMB connector to input the data streams for the bit-error-rate measurements. The rising
(positive) or falling (negative) edge of the BER CLK IN signal (selected by the softkey or the SCPI
command) is used to trigger the reading of the data. The damage levels are > +5.5 volts and < −0.5 volts. This
connector accepts a high impedance TTL-compatible signal or a 75Ω input.
5. I-bar OUT Connector (Option 001/601 or 002/602)
This female BNC connector is used in conjunction with the I OUT connector to provide a balanced baseband
stimulus. Balanced signals are signals present in two separate conductors that are symmetrical relative to
ground, and are opposite in polarity (180 degrees out of phase). The nominal output impedance of this
connector is 50Ω, DC-coupled. The damage levels are > +2 V and < −2 V. The DC origin offset is typically
< 10 mV. The output signal levels into a 50Ω load are as follows:
•
0.5 Vpk, typical, corresponds to one unit length of the I/Q vector.
•
0.69 Vpk (2.84 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.5.
•
0.71 Vpk (3.08 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.35.
•
Typically 1 Vp-p maximum (Option 001/601or 002/602 only).
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If you configure your signal generator with Option 1EM, this output is relocated and changed from a BNC to
an SMB connector.
6. I OUT Connector (Option 001/601 or 002/602)
This female BNC connector outputs the analog, in-phase component of I/Q modulation from the internal
baseband generator. The nominal output impedance of this connector is 50Ω, DC-coupled. The damage
levels are > +3.5 V and < −3.5 V. The DC origin offset is typically < 10 mV. The output signal levels into a
50Ω load are as follows:
•
0.5 Vpk, typical, corresponds to one unit length of the I/Q vector.
•
0.69 Vpk (2.84 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.5.
•
0.71 Vpk (3.08 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.35.
•
Typically 1 Vp-p maximum.
If you configure your signal generator with Option 1EM, this output is relocated from a BNC to an SMB
connector.
7. COH CARRIER Output Connector
The coherent carrier connector outputs RF that is modulated with FM or ΦM. The output power is nominally
–2 dBm ±5 dB. The output frequency range is from 249.99900001 MHz to the maximum specified
frequency of your signal generator or 4 GHz for Option 506 instruments. If the RF output frequency is
below this range, the coherent carrier output signal will have the following frequency: Frequency of
coherent carrier = (1E9 − Frequency of RF output) in Hz. The damage levels are 20 Vdc and 13 dBm reverse
RF power.
8. Q OUT Connector (Option 001/601 or 002/602)
This female BNC connector outputs the analog, quadrature-phase component of I/Q modulation from the
internal baseband generator. The nominal output impedance of this connector is 50Ω, DC-coupled. The
damage levels are > +3.5 V and < −3.5 V. The DC origin offset is typically < 10 mV. The output signal
levels into a 50Ω load are as follows:
•
•
•
•
0.5 Vpk, typical, corresponds to one unit length of the I/Q vector.
0.69 Vpk (2.84 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.5.
0.71 Vpk (3.08 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.35.
Typically 1 Vp-p maximum.
If you configure your signal generator with Option 1EM, this output is relocated from a BNC to an SMB
connector.
Chapter 2
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E4438C Vector Signal Generator Overview
Rear Panel Overview
9. Q-bar OUT Connector (Option 001/601 or 002/602)
This female BNC connector is used in conjunction with the Q OUT connector to provide a balanced
baseband stimulus. Balanced signals are signals present in two separate conductors that are symmetrical
relative to ground, and are opposite in polarity (180 degrees out of phase). The nominal output impedance of
this connector is 50Ω, DC-coupled. The damage levels are > +2 V and < −2 V. The DC origin offset is
typically < 10 mV. The output signal levels into a 50Ω load are as follows:
•
•
•
•
0.5 Vpk, typical, corresponds to one unit length of the I/Q vector.
0.69 Vpk (2.84 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.5.
0.71 Vpk (3.08 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.35.
Typically 1 Vp-p maximum.
If you configure your signal generator with Option 1EM, this output is relocated from a BNC to an SMB
connector.
10. EVENT 1 Connector (Option 001/601 or 002/602)
This female BNC connector outputs a pulse that can be used to trigger the start of a data pattern, frame, or
timeslot. It is adjustable to within plus or minus one timeslot with one bit of resolution. With Option 401
installed, an even second output is generated. A marker is output every two seconds indicating the beginning
of each short code sequence for use in synchronizing CDMA analysis instruments.
There is a marker on/off condition associated with each waveform point. The marker 1 level is +3.3 V
CMOS high when positive polarity is selected; –3.3 V CMOS low when negative polarity is selected. The
output on the EVENT 1 connector occurs whenever Marker 1 is turned on in the waveform. (Markers are
automatically turned on whenever you set them in a waveform segment. When you combine waveform
segments that contain Marker 1 into a sequence, the markers are automatically turned off until you toggle
them on in either the Edit Selected Waveform Sequence menu or in the Build New Waveform Sequence
menu.)
The damage levels for the Event 1 connector are > +8 V and < −4 V. On signal generators with Option 1EM,
this output is changed from a BNC to an SMB connector. With Option 401 you can select from several
different output signals for this connector.
11. EVENT 2 Connector (Option 001/601 or 002/602)
This female BNC connector outputs a data enable signal for gating external equipment. The output is
applicable when the external data is clocked into internally generated timeslots. Data is enabled when the
signal is low. With Option 401 installed, a marker is output on the EVENT 2 connector every
26.67 milliseconds, corresponding to the start of each short code.
There is a marker on/off condition associated with each waveform point. The marker 2 level is +3.3 V
CMOS high when positive polarity is selected; –3.3 V CMOS low when negative polarity is selected. The
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Chapter 2
E4438C Vector Signal Generator Overview
Rear Panel Overview
output on the EVENT 1 connector occurs whenever Marker 1 is turned on in the waveform.The output on
the EVENT 2 connector occurs whenever Marker 2 is turned on in the waveform. (Markers are
automatically turned on whenever you set them in a waveform segment. When you combine waveform
segments that contain Marker 2 into a sequence, the markers are automatically turned off until you toggle
them on in either the Edit Selected Waveform Sequence menu or in the Build New Waveform Sequence
menu.)
The damage levels are > +8 V and < −4 V. On signal generators with Option 1EM, this output is changed
from a BNC to an SMB connector. With Option 401 this connector is used for system reset output.
12. PATT TRIG IN Connector (Option 001/601 or 002/602)
This female BNC input connector can accept either a CMOS low to CMOS high, or CMOS high to CMOS
low edge trigger. The minimum trigger input pulse width, high or low, is 100 ns. The damage levels are
> +5.5 volts and < −0.5 volts. If you configure your signal generator with Option 1EM, this input is
changed from a BNC to an SMB connector.
The input to the PATT TRIG IN connector is used to trigger the internal digital modulation pattern generator
to start a single pattern output or to stop and re-synchronize a pattern that is being continuously output. The
trigger edge is latched and then sampled by the falling edge of the internal data bit clock to synchronize the
trigger with the data bit clock timing. The minimum delay from the trigger edge to the first bit of the frame
is 1.5 to 2.5 bit clock periods.
This connector is the source for the external trigger for all of the ARB waveform generator triggers. With
Option 401, this connector is used for even second synchronization input.
13. AUX I/O Connector
This female 37-pin connector is active only on instruments with an internal baseband generator (Option
001/601or 002/602). On signal generators without one of these options, this connector is non-functional.
This connector provides access to the inputs and outputs described in the following table and shown in
Figure 2-5.
Connector Pin
Description
ALT PWR IN
Pin-16 is used with an internal baseband generator. This pin accepts a CMOS signal for
synchronization of external data and alternate power signal timing. Damage levels are >
+5.5 volts and < −0.5 volts.
DATA CLK OUT
Pin-6 is used with an internal baseband generator. This pin relays a CMOS bit clock
signal for synchronizing serial data. Damage levels are > +5.5 volts and < −0.5 volts.
DATA OUT
Pin-7 is used with an internal baseband generator. This pin outputs data (CMOS) from
the internal data generator or the externally supplied signal at data input. Damage levels
are > +5.5 volts and < −0.5 volts.
Chapter 2
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E4438C Vector Signal Generator Overview
Rear Panel Overview
Connector Pin
EVENT 3
Description (Continued)
Pin-19 is used with an internal baseband generator. In arbitrary waveform mode, this pin
outputs a timing signal generated by Marker 3.
The marker 3 output level is +3.3 V CMOS regardless of marker polarity settings.The
reverse damage levels for this connector pin are > +5.5 volts and < −0.5 volts.
EVENT 4
Pin-18 is used with an internal baseband generator. In arbitrary waveform mode, this pin
outputs a timing signal generated by Marker 4.
The marker 4 output level is +3.3 V CMOS regardless of marker polarity settings. The
reverse damage levels for this connector pin are > +5.5 volts and < −0.5 volts.
PATT TRIG IN 2
Pin-17 accepts a signal that triggers an internal pattern or frame generator to start single
pattern output. Minimum pulse width is 100 ns. Damage levels are > +5.5 and < −0.5 V.
SYM SYNC OUT
Pin-5 is used with an internal baseband generator. This pin outputs the CMOS symbol
clock for symbol synchronization, one data clock period wide. Damage levels are >
+5.5 volts and < −0.5 volts.
BER MEAS TRIG/BER
NO DATA
Pin-22 is used for bit error rate testing (Option UN7). Damage levels are > +5.5 volts
and < −0.5 volts.
BER ERR OUT
Pin-21 is used for bit error rate testing (Option UN7). Damage levels are > +5.5 volts
and < −0.5 volts
BER TEST OUT
Pin-20 is used for bit error rate testing (Option UN7). Damage levels are > +5.5 volts
and < −0.5 volts
BER SYNC LOSS
Pin-4 is used for bit error rate testing (Option UN7). Damage levels are > +5.5 volts and
< −0.5 volts.
BER MEAS END
Pin-1 is used for bit error rate testing (Option UN7). Damage levels are > +5.5 volts and
< −0.5 volts.
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Rear Panel Overview
Figure 2-5
AUX I/O Pin Configuration
View looking into
rear panel connector
14. DIGITAL BUS
This is a proprietary bus used for Agilent Baseband Studio products, which require Option 601 or 602. This
connector is not operational for general purpose customer use. Signals are present only when a Baseband
Studio option is installed (for details, refer to www.agilent.com/find/basebandstudio).
15. AC Power Receptacle
The power cord receptacle accepts a three-pronged cable that is shipped with the signal generator. The line
voltage is connected here.
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E4438C Vector Signal Generator Overview
Rear Panel Overview
16. GPIB Connector
The GPIB connector allows communications with compatible devices such as external controllers. It is
functionally equivalent to the LAN and RS 232 connectors.
17. RS 232 Connector
This female DB-9 connector is an RS-232 serial port that can be used for controlling the signal generator
remotely. It is functionally equivalent to the GPIB and LAN connectors. The following table shows the
description of the pinouts. Figure 2-6 shows the pin configuration.
Table 2-1
RS 232 Connector
Pin Number
Signal Description
Signal Name
1
No Connection
2
Receive Data
RECV
3
Transmit Data
XMIT
4
+5 V
5
Ground, 0 V
6
No Connection
7
Request to Send
RTS
8
Clear to Send
CTS
9
No Connection
Figure 2-6
View looking into
rear panel connector
18. LAN Connector
LAN based communication is supported by the signal generator via the LAN (local area network) connector.
The LAN connector enables the signal generator to be remotely programmed by a LAN-connected
computer. The distance between a computer and the signal generator is limited to 100 meters (10Base-T) on
a single cable. For more information about the LAN, refer to the E4428C/38C ESG Signal Generators
Programming Guide.
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E4438C Vector Signal Generator Overview
Rear Panel Overview
19. TRIG OUT Connector
This female BNC connector outputs a TTL signal that is asserted high at the start of a dwell sequence, or at
the start of waiting for the point trigger in manual sweep mode. It is asserted low when the dwell is over,
when the point trigger is received, or once per sweep during an LF sweep. The logic polarity can be
reversed.
20. BURST GATE IN Connector (Option 001/601 or 002/602)
The female BNC connector accepts a CMOS signal for gating burst power in digital modulation
applications. The burst gating is used when you are externally supplying data and clock information. The
input signal must be synchronized with the external data input that will be output during the burst. The burst
power envelope and modulated data are internally delayed and re-synchronized. The input signal must be
CMOS high for normal burst RF power or CW RF output power and CMOS low for RF off. The leading
edges must be synchronous with the DATA CLOCK rising edges. The damage levels are > +5.5 volts and
< −0.5 volts.
If you configure your signal generator with Option 1EM, this output is changed from a BNC to an SMB
connector. With Option 401, this connector is used for system reset trigger input.
21. TRIG IN Connector
This female BNC connector accepts a CMOS signal for triggering operations, such as point-to-point in
manual sweep mode or an LF sweep in external sweep mode. Triggering can occur on either the positive or
negative edge. The damage levels are > +5.5 volts and < −0.5 volts.
22. 10 MHz IN Connector
This female BNC connector accepts a −3.5 to +20 dBm signal from an external timebase reference that is 1,
2, 5, or 10 MHz ±0.2 ppm. The nominal input impedance is 50Ω. The signal generator detects when a valid
reference signal is present at this connector and automatically switches from internal to external reference
operation. The signal generator will only automatically switch from internal to external reference operation
when the instrument is in its factory default mode where the Ref Oscillator Source Auto Off On softkey is set to
on.
23. SWEEP OUT Connector
This female BNC connector provides a voltage range of 0 to +10 V. When the signal generator is sweeping,
the SWEEP OUT signal ranges from 0 V at the beginning of the sweep to +10 V at the end of the sweep
regardless of the sweep width. In CW mode this connector has no output. The output impedance is less than
1Ω and can drive 2 kΩ.
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E4438C Vector Signal Generator Overview
Rear Panel Overview
24. 10 MHz OUT Connector
This female BNC connector provides a nominal signal level of +3.9 dBm ±2 dB, and an output impedance
of 50Ω. The accuracy is determined by the timebase used.
25. BASEBAND GEN REF IN Connector (Option 001/601 or 002/602)
The BASEBAND GEN REF IN connector accepts a 0 to +20 dBm sine wave or TTL square wave signal
from an external timebase reference. This digital modulation reference clock is used by the internal
baseband generator for both component and receiver test applications (only the internal baseband generator
can be locked to this external reference; the RF frequency remains locked to the 10 MHz reference). The
nominal input impedance is 50Ω at 13 MHz, AC-coupled.
This connector accepts a TTL or > −10 dBm sine wave external reference at rates from 250 kHz through
100 MHz. The internal clock for the arbitrary waveform generator is locked to this signal when external
reference is selected in the ARB setup. The minimum pulse width must be > 10 ns. The damage levels are
> +8 V and < −8 V.
This female BNC connector is provided only on signal generators with Options 001/601 and 002/602. On
signal generators with Option 1EM, this output is changed from a BNC to an SMB connector.
When using the real-time W-CDMA uplink personality, this connector is used to connect the external
baseband generator data clock.
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Chapter 2
3
Basic Operation
The following list shows the topics covered in this chapter:
•
“Using Table Editors” on page 48
•
“Configuring the RF Output” on page 50
•
“Generating the Modulation Format” on page 58
•
“Modulating the Carrier Signal” on page 60
•
“Creating and Applying User Flatness Correction” on page 61
•
“Using the Memory Catalog” on page 68
•
“Using the Instrument State Registers” on page 70
•
“Using Security Functions” on page 75
•
“Enabling Options (E4438C Only)” on page 84
•
“Using the Web Server” on page 85
47
Basic Operation
Using Table Editors
Using Table Editors
The signal generator table editors enable you to simplify configuration tasks, such as creating a list sweep.
This section familiarizes you with basic table editor functionality using the List Mode Values table editor as
an example.
Press Preset > Sweep/List > Configure List Sweep.
The signal generator displays the List Mode Values table editor, as shown below.
Figure 3-1
Active Function Area
Table Editor Name
Cursor
Table Items
Table Editor Softkeys
Active Function Area
displays the active table item while its value is edited.
Cursor
an inverse video identifier used to highlight specific table items for
selection and editing.
Table Editor Softkeys
select table items, preset table values, and modify table structures.
Table Items
values arranged in numbered rows and titled columns (The columns
are also known as data fields. For example, the column below the
Frequency title is known as the Frequency data field).
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Chapter 3
Basic Operation
Using Table Editors
Table Editor Softkeys
The following table editor softkeys are used to load, navigate, modify, and store table item values. Press
More (1 of 2) to access Load/Store and its associated softkeys.
Edit Item
displays the selected item in the active function area of the display where the item’s
value can be modified.
Insert Row
inserts an identical row of table items above the currently selected row.
Delete Row
deletes the currently selected row.
Goto Row
opens a menu of softkeys (Enter, Goto Top Row, Goto Middle Row, Goto Bottom Row, Page Up,
and Page Down) used to quickly navigate through the table items.
Insert Item
inserts an identical item in a new row below the currently selected item.
Delete Item
deletes the item from the bottom row of the currently selected column.
Page Up and
Page Down
Load/Store
displays table items that occupy rows outside the limits of the ten-row table display
area.
opens a menu of softkeys (Load From Selected File, Store To File, Delete File, Goto Row, Page
Up, and Page Down) used to load table items from a file in the memory catalog, or to
store the current table items as a file in the memory catalog. The signal generator
accepts a file name with a maximum length of 23 characters (alphanumeric and special
characters).
Modifying Table Items in the Data Fields
To modify existing table items:
1. Use the arrow keys or the knob to move the table cursor over the desired item. In Figure 3-1 on page 48,
the first item in the Frequency data field has been selected.
2. Press Edit Item.
The selected item is displayed in the active function area of the display.
3. Use the knob, arrow keys, or the numeric keypad to modify the value.
4. Press Enter.
The modified item is now displayed in the table.
Chapter 3
49
Basic Operation
Configuring the RF Output
Configuring the RF Output
This section will show you how to create continuous wave and swept RF outputs.
Configuring a Continuous Wave RF Output
Using these procedures, you will learn how to set the following parameters:
•
RF output frequency
•
frequency reference and frequency offset
•
RF output amplitude
•
amplitude reference and amplitude offset
Setting the RF Output Frequency
1. Press Preset.
This returns the signal generator to the factory-defined state.
NOTE
You can change the preset condition of the signal generator to a user-defined state. For these
examples, however, use the factory-defined preset state (the Preset Normal User softkey in
the Utility menu must be set to Normal).
2. Observe the FREQUENCY area of the display (in the upper left-hand corner).
The value displayed is the maximum specified frequency of the signal generator.
3. Press RF On/Off.
The RF On/Off hardkey must be pressed before the RF signal is available at the RF OUTPUT connector.
The display annunciator changes from RF OFF to RF ON. The maximum specified frequency is now
being output at the RF OUTPUT connector (at the signal generator’s minimum power level).
4. Press Frequency > 700 > MHz.
The 700 MHz RF frequency is now displayed in the FREQUENCY area of the display and also in the
active entry area.
5. Press Frequency > Incr Set > 1 > MHz.
This changes the frequency increment value to 1 MHz.
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Chapter 3
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Configuring the RF Output
6. Press the up arrow key.
Each press of the up arrow key increases the frequency by the increment value last set with the Incr Set
hardkey. The increment value is displayed in the active entry area.
7. The down arrow decreases the frequency by the increment value set in the previous step. Practice
stepping the frequency up and down in 1 MHz increments.
You can also adjust the RF output frequency using the knob. As long as frequency is the active function
(the frequency is displayed in the active entry area), the knob will increase and decrease the RF output
frequency.
8. Use the knob to adjust the frequency back to 700 MHz.
Setting the Frequency Reference and Frequency Offset
The following procedure sets the RF output frequency as a reference frequency to which all other frequency
parameters are relative. The frequency initially shown on the display will be 0.00 Hz (the frequency output
by the hardware minus the reference frequency). Although the display changes, the frequency output does
not change. Any subsequent frequency changes are shown as incremental or decremental to 0 Hz.
1. Press Preset.
2. Press Frequency > 700 > MHz.
3. Press Freq Ref Set.
This activates the frequency reference mode and sets the current output frequency (700 MHz) as the
reference value. The FREQUENCY area displays 0.00 Hz, which is the frequency output by the
hardware (700 MHz) minus the reference value (700 MHz). The REF indicator is activated and the
Freq Ref Off On softkey has toggled to On.
4. Press RF On/Off.
The display annunciator has changed from RF OFF to RF ON. The RF frequency at the RF OUTPUT
connector is 700 MHz.
5. Press Frequency > Incr Set > 1 > MHz.
This changes the frequency increment value to 1 MHz.
6. Press the up arrow key.
This increments the output frequency by 1 MHz. The FREQUENCY area display changes to show
1.000 000 00 MHz, which is the frequency output by the hardware (700 MHz + 1 MHz) minus the
reference frequency (700 MHz). The frequency at the RF OUTPUT changes to 701 MHz.
Chapter 3
51
Basic Operation
Configuring the RF Output
7. Press Freq Offset > 1 > MHz.
This enters a 1 MHz offset. The FREQUENCY area displays 2.000 000 00 MHz, which is the
frequency output by the hardware (701 MHz) minus the reference frequency (700 MHz) plus the offset
(1 MHz). The OFFS indicator is activated. The frequency at the RF OUTPUT connector is still
701 MHz.
Setting the RF Output Amplitude
1. Press Preset.
2. Observe the AMPLITUDE area of the display.
The display reads the minimum power level of the signal generator. This is the normal preset RF output
amplitude.
3. Press RF On/Off.
The display annunciator changes from RF OFF to RF ON. The RF signal is now being output at the
minimum power level at the RF OUTPUT connector.
4. Press Amplitude > –20 > dBm.
This changes the amplitude to −20 dBm. The new −20 dBm RF output power is now displayed in the
AMPLITUDE area of the display and also in the active entry area.
Amplitude is still the active function until you press another front panel function key. You can also
change the amplitude using the up and down arrow keys and the knob.
Setting the Amplitude Reference and Amplitude Offset
The following procedure sets the RF output power as an amplitude reference to which all other amplitude
parameters are relative. The amplitude initially shown on the display will be 0 dB (the power output by the
hardware minus the reference power). Although the display changes, the output power does not change. Any
subsequent power changes are shown as incremental or decremental to 0 dB.
1. Press Preset.
2. Press Amplitude > –20 > dBm.
3. Press More (1 of 2) > Ampl Ref Set.
This activates the amplitude reference mode and sets the current output power (−20 dBm) as the
reference value. The AMPLITUDE area displays 0.00 dB, which is the power output by the hardware
(20 dBm) minus the reference value (−20 dBm). The REF indicator is activated and the Ampl Ref Off On
softkey has toggled to On.
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Chapter 3
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Configuring the RF Output
4. Press RF On/Off.
The display annunciator has changed from RF OFF to RF ON. The power at the RF OUTPUT connector
is −20 dBm.
5. Press Incr Set > 10 > dB.
This changes the amplitude increment value to 10 dB.
6. Use the up arrow key to increase the output power by 10 dB.
The AMPLITUDE area displays 10.00 dB, which is the power output by the hardware (−20 dBm plus
10 dBm) minus the reference power (−20 dBm). The power at the RF OUTPUT connector changes to
−10 dBm.
7. Press Ampl Offset > 10 > dB.
This enters a 10 dB offset. The AMPLITUDE area displays 20.00 dB, which is the power output by the
hardware (−10 dBm) minus the reference power (−20 dBm) plus the offset (10 dB). The OFFS indicator
is activated. The power at the RF OUTPUT connector is still −10 dBm.
Configuring a Swept RF Output
The signal generator has two sweep types: step and list.
NOTE
List sweep data cannot be saved within an instrument state, but can be saved to the memory
catalog. For instructions on saving list sweep data, see “Storing Files” on page 69.
During swept RF output, the FREQUENCY and AMPLITUDE areas of the signal generator’s
display are deactivated, depending on what is being swept.
This section provides an explanation of the differences between step sweep and list sweep. You will learn
two ways to configure the signal generator’s RF output to sweep a defined set of frequency and amplitude
points. You will create a step sweep and then you will use these points as the basis for a new list sweep.
Step Sweep
When a step sweep is activated, the signal generator sweeps the RF output based on the values entered for
RF output start and stop frequencies and amplitudes, a number of equally spaced points (steps) to dwell
upon, and the amount of dwell time at each point. The frequency, amplitude, or frequency and amplitude of
the RF output will sweep from the start amplitude/frequency to the stop amplitude/frequency, dwelling at
equally spaced intervals defined by the # Points softkey value.
Step sweep provides a linear progression through the start-to-stop frequency and/or amplitude values. You
can toggle the direction of the sweep, up or down. When the Sweep Direction Down Up softkey is set to Up,
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Configuring the RF Output
values are swept from the start frequency/amplitude to the stop frequency/amplitude. When set to Down,
values are swept from the stop frequency/amplitude to the start frequency/amplitude.
Configuring and Activating a Single Step Sweep
In this procedure, you will create a step sweep with nine, equally spaced points and the following
parameters:
•
frequency range from 500 MHz to 600 MHz
•
amplitude from −20 dBm to 0 dBm
•
dwell time 500 ms at each point
1. Press Preset.
2. Press Sweep/List.
This opens a menu of sweep softkeys.
3. Press Sweep Repeat Single Cont.
This toggles the sweep repeat from continuous to single.
4. Press Configure Step Sweep.
5. Press Freq Start > 500 > MHz.
This changes the start frequency of the step sweep to 500 MHz.
6. Press Freq Stop > 600 > MHz.
This changes the stop frequency of the step sweep to 600 MHz.
7. Press Ampl Start > -20 > dBm.
This changes the amplitude level for the start of the step sweep.
8. Press Ampl Stop > 0 > dBm.
This changes the amplitude level for the end of the step sweep.
9. Press # Points > 9 > Enter.
This sets the number of sweep points to nine.
10. Press Step Dwell > 500 > msec.
This sets the dwell time at each point to 500 milliseconds.
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Configuring the RF Output
11. Press Return > Sweep > Freq & Ampl.
This sets the step sweep to sweep both frequency and amplitude data. Selecting this softkey returns you
to the previous menu and turns on the sweep function.
12. Press RF On/Off.
The display annunciator changes from RF OFF to RF ON.
13. Press Single Sweep.
A single sweep of the frequencies and amplitudes configured in the step sweep is executed and available
at the RF OUTPUT connector. On the display, the SWEEP annunciator appears for the duration of the
sweep, and a progress bar shows the progression of the sweep. The Single Sweep softkey can also be used
to abort a sweep in progress.
Activating Continuous Step Sweep
Press Sweep Repeat Single Cont.
This toggles the sweep from single to continuous. A continuous repetition of the frequencies and amplitudes
configured in the step sweep are now available at the RF OUTPUT connector. The SWEEP annunciator
appears on the display, indicating that the signal generator is sweeping, and progression of the sweep is
shown by a progress bar.
List Sweep
List sweep allows you to create a list of arbitrary frequency, amplitude, and dwell time values and sweep the
RF output based on the entries in the List Mode Values table.
Unlike a step sweep that contains linear ascending/descending frequency and amplitude values spaced at
equal intervals throughout the sweep, list sweep frequencies and amplitudes can be entered at unequal
intervals, nonlinear ascending/descending, or random order.
For convenience, the List Mode Values table can be copied from a previously configured step sweep. Each
step sweep point’s associated frequency, amplitude and dwell time values are entered into a row in the List
Mode Values table, as the following example illustrates.
Configuring a List Sweep Using Step Sweep Data
In this procedure, you will leverage the step sweep points and change the sweep information by editing
several points in the List Mode Values table editor. For information on using table editors, see “Using Table
Editors” on page 48.
1. Press Sweep Repeat Single Cont.
This toggles the sweep repeat from continuous to single. The SWEEP annunciator is turned off. The
sweep will not occur until it is triggered.
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Configuring the RF Output
2. Press Sweep Type List Step.
This toggles the sweep type from step to list.
3. Press Configure List Sweep.
This opens another menu displaying softkeys that you will use to create the sweep points. The display
shows the current list data. (When no list has been previously created, the default list contains one point
set to the signal generator’s maximum frequency, minimum amplitude, and a dwell time of 2 ms.)
4. Press More (1 of 2) > Load List From Step Sweep > Confirm Load From Step Sweep.
The points you defined in the step sweep are automatically loaded into the list.
Editing List Sweep Points
1. Press Return > Sweep > Off.
Turning the sweep off allows you to edit the list sweep points without generating errors. If sweep
remains on during editing, errors occur whenever one or two point parameters (frequency, power, and
dwell) are undefined.
2. Press Configure List Sweep.
This returns you to the sweep list table.
3. Use the arrow keys to highlight the dwell time in row 1.
4. Press Edit Item.
The dwell time for point 1 becomes the active function.
5. Press 100 > msec.
This enters 100 ms as the new dwell time value for row 1. Note that the next item in the table (in this
case, the frequency value for point 2) becomes highlighted after you press the terminator softkey.
6. Using the arrow keys, highlight the frequency value in row 4.
7. Press Edit Item > 545 > MHz.
This changes the frequency value in row 4 to 545 MHz.
8. Highlight any column in the point 7 row and press Insert Row.
This adds a new point between points 7 and 8. A copy of the point 7 row is placed between points 7 and
8, creating a new point 8, and renumbering the successive points.
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Configuring the RF Output
9. Highlight the frequency item for point 8, then press Insert Item.
Pressing Insert Item shifts frequency values down one row, beginning at point 8. Note that the original
frequency values for both points 8 and 9 shift down one row, creating an entry for point 10 that contains
only a frequency value (the power and dwell time items do not shift down).
The frequency for point 8 is still active.
10. Press 590 > MHz.
11. Press Insert Item > −2.5 > dBm.
This inserts a new power value at point 8 and shifts down the original power values for points 8 and 9 by
one row.
12. Highlight the dwell time for point 9, then press Insert Item.
A duplicate of the highlighted dwell time is inserted for point 9, shifting the existing value down to
complete the entry for point 10.
Activating List Sweep for a Single Sweep
1. Press Return > Sweep > Freq & Ampl
This turns the sweep on again. No errors should occur if all parameters for every point have been defined
in the previous editing process.
2. Press Single Sweep.
The signal generator will single sweep the points in your list. The SWEEP annunciator activates during
the sweep.
3. Press More (1 of 2) > Sweep Trigger > Trigger Key.
This sets the sweep trigger to occur when you press the Trigger hardkey.
4. Press More (2 of 2) > Single Sweep.
This arms the sweep. The ARMED annunciator is activated.
5. Press the Trigger hardkey.
The signal generator will single sweep the points in your list and the SWEEP annunciator will be
activated during the sweep.
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Basic Operation
Generating the Modulation Format
Generating the Modulation Format
The modulation format can be turned on prior to or after setting your signal parameters. Perform the
following steps to turn the modulation format on:
1. Access the first menu within the modulation format.
This menu will show a softkey that has the format’s name associated with off and on. For example, AM
Off On. For some formats, the off/on key may appear in additional menus other than the first one.
2. Press the modulation format off/on key until On is highlighted.
Figure 3-2 shows the AM modulation format’s first menu with off as the format status, and Figure 3-3 shows
an example of the ESG display when the format is active.
The modulation format is now generated, however the carrier signal is not modulated until the Mod On/Off
key has been set to on. Depending on the modulation format, the signal generator may require a few seconds
to build the signal. Within the digital formats, you may see a BaseBand Reconfiguring status bar
appear on the display. Once the signal is generated, an annunciator showing the name of the format will
appear on the display indicating that the modulation format is active. For digital formats, the I/Q
annunciator will appear in addition to the name of the modulation format.
Figure 3-2
Modulation Format Off
First AM Menu
Modulation Format is Off
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Basic Operation
Generating the Modulation Format
Figure 3-3
Modulation Format On
Active Modulation Format Annunciator
First AM Menu
Modulation format is On
Chapter 3
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Basic Operation
Modulating the Carrier Signal
Modulating the Carrier Signal
The carrier signal is modulated when the Mod On/Off key is set to on and a modulation format is active.
When the key is set to on, the MOD ON annunciator shows in the display. The MOD OFF annunciator appears
when the key is set to off. The MOD ON annunciator may be showing even when there are no active
modulation formats. This just indicates that the carrier signal will be modulated when a modulation format is
turned on.
To Turn the Modulation On
Press the Mod On/Off key until the MOD ON annunciator appears in the display.
The carrier signal is now modulated with all active modulation formats. This is the factory default.
To Turn the Modulation Off
Press the Mod On/Off key until the MOD OFF annunciator appears in the display.
The carrier signal is no longer modulated or capable of being modulated when a modulation format is active.
Figure 3-4
Carrier Signal Modulation Status
Mod set to On—Carrier is Modulated
AM Modulation Format is Active
Mod set to Off—Carrier is
not Modulated
AM Modulation Format is Active
Mod set to On—Carrier is
not Modulated
No Active Modulation Format
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Creating and Applying User Flatness Correction
Creating and Applying User Flatness Correction
User flatness correction allows the digital adjustment of RF output amplitude for up to 1601 frequency
points in any frequency or sweep mode. Using an Agilent E4416A/17A or E4418B/19B power meter
(controlled by the signal generator through GPIB) to calibrate the measurement system, a table of power
level corrections is created for frequencies where power level variations or losses occur. These frequencies
may be defined in sequential linear steps or arbitrarily spaced.
If you do not have an Agilent E4416A/17A or E4418B/19B power meter, or if your power meter does not
have a GPIB interface, the correction values can be manually entered into the signal generator.
To allow different correction arrays for different test setups or different frequency ranges, you may save
individual user flatness correction tables to the signal generator’s memory catalog and recall them on
demand.
Follow the steps in the next sections to create and apply user flatness correction to the signal generator’s RF
output.
Afterward, follow the steps in “Recalling and Applying a User Flatness Correction Array” on page 66 to
recall a user flatness file from the memory catalog and apply it to the signal generator’s RF output.
Creating a User Flatness Correction Array
In this example, you will create a user flatness correction array. The flatness correction array contains ten
frequency correction pairs (amplitude correction values for specified frequencies), from 500 MHz to 1 GHz.
An Agilent E4416A/17A/18B/19B power meter (controlled by the signal generator via GPIB) and E4413A
power sensor are used to measure the RF output amplitude at the specified correction frequencies and
transfer the results to the signal generator. The signal generator reads the power level data from the power
meter, calculates the correction values, and stores the correction pairs in the user flatness correction array.
If you do not have the required Agilent power meter, or if your power meter does not have a GPIB interface,
you can enter correction values manually.
Required Equipment
•
Agilent E4416A/17A/18B/19B power meter
•
Agilent E4413A E Series CW power sensor
•
GPIB interface cable
•
adapters and cables, as required
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Creating and Applying User Flatness Correction
Configure the Power Meter
1. Select SCPI as the remote language for the power meter.
2. Zero and calibrate the power sensor to the power meter.
3. Enter the appropriate power sensor calibration factors into the power meter as appropriate.
4. Enable the power meter’s cal factor array.
NOTE
For operating information on your particular power meter/sensor, refer to its operating
guide.
Connect the Equipment
Connect the equipment as shown in Figure 3-5 on page 63.
NOTE
62
During the process of creating the user flatness correction array, the power meter is
controlled by the signal generator via GPIB. No other controllers are allowed on the GPIB
interface.
Chapter 3
Basic Operation
Creating and Applying User Flatness Correction
Figure 3-5
User Flatness Correction Equipment Setup
Configure the Signal Generator
1. Press Preset.
2. Configure the signal generator to interface with the power meter.
a. Press Amplitude > More (1 of 2) > User Flatness > More (1 of 2) > Power Meter > E4416A, E4417A, E4418B,
or E4419B.
b. Press Meter Address > enter the power meter’s GPIB address > Enter.
c. For E4417A and E4419B power meters, press Meter Channel A B to select the power meter’s active
channel.
d. Press Meter Timeout to adjust the length of time before the instrument generates a timeout error if
unsuccessfully attempting to communicate with the power meter.
3. Press More (2 of 2) > Configure Cal Array > More (1 of 2) > Preset List > Confirm Preset.
This opens the User Flatness table editor and presets the cal array frequency/correction list.
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Creating and Applying User Flatness Correction
4. Press Configure Step Array.
This opens a menu for entering the user flatness step array data.
5. Press Freq Start > 500 > MHz.
6. Press Freq Stop > 1 > GHz.
7. Press # of Points > 10 > Enter.
Steps 4, 5, and 6 enter the desired flatness-corrected frequencies into the step array.
8. Press Return > Load Cal Array From Step Array > Confirm Load From Step Sweep.
This populates the user flatness correction array with the frequency settings defined in the step array.
9. Press Amplitude > 0 > dBm.
10. Press RF On/Off.
This activates the RF output and the RF ON annunciator is displayed on the signal generator.
Perform the User Flatness Correction
NOTE
If you are not using an Agilent E4416A/17A/18B/19B power meter, or if your power meter
does not have a GPIB interface, you can perform the user flatness correction manually. For
instructions, see “Performing the User Flatness Correction Manually” on page 65.
1. Press More (1 of 2) > User Flatness > Do Cal.
This creates the user flatness amplitude correction value table entries. The signal generator enters the
user flatness correction routine and a progress bar is shown on the display.
2. When prompted, press Done.
This loads the amplitude correction values into the user flatness correction array.
If desired, press Configure Cal Array.
This opens the user flatness correction array, where you can view the stored amplitude correction values.
The user flatness correction array title displays User Flatness: (UNSTORED) indicating that the
current user flatness correction array data has not been saved to the memory catalog.
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Creating and Applying User Flatness Correction
Performing the User Flatness Correction Manually
If you are not using an Agilent E4416A/17A/18B/19B power meter, or if your power meter does not have a
GPIB interface, complete the steps in this section and then continue with the user flatness correction tutorial.
1. Press More (1 of 2) > User Flatness > Configure Cal Array.
This opens the User Flatness table editor and places the cursor over the frequency value (1 GHz) for
row 1. The RF output changes to the frequency value of the table row containing the cursor and
1.000 000 000 00 is displayed in the FREQUENCY area of the display.
2. Observe and record the measured value from the power meter.
3. Subtract the measured value from 0 dBm.
4. Move the table cursor over the correction value in row 1.
5. Press Edit Item > enter the difference value from step 3 > dB.
The signal generator adjusts the RF output amplitude based on the correction value entered.
6. Repeat steps 2 through 5 until the power meter reads 0 dBm.
7. Use the down arrow key to place the cursor over the frequency value
for the next row. The RF output changes to the frequency value of the table row containing the cursor, as
shown in the FREQUENCY area of the display.
8. Repeat steps 2 through 7 for every entry in the User Flatness table.
Save the User Flatness Correction Data to the Memory Catalog
This process allows you to save the user flatness correction data in the signal generator’s memory catalog.
With several user flatness correction files saved to the memory catalog, any file can be recalled, loaded into
the correction array, and applied to the RF output to satisfy specific RF output flatness requirements.
1. Press Load/Store.
2. Press Store to File.
3. Enter the file name FLATCAL1 using the alphanumeric softkeys, numeric keypad, or the knob.
The maximum file name length is 23 characters (alphanumeric and special characters).
4. Press Enter.
The user flatness correction array file FLATCAL1 is now stored in the memory catalog as a UFLT file.
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Creating and Applying User Flatness Correction
Applying a User Flatness Correction Array
Press Return > Return > Flatness Off On.
This applies the user flatness correction array to the RF output. The UF indicator is activated in the
AMPLITUDE section of the signal generator’s display and the frequency correction data contained in the
correction array is applied to the RF output amplitude.
Recalling and Applying a User Flatness Correction Array
Before performing the steps in this section, complete “Creating a User Flatness Correction Array” on
page 61.
1. Press Preset.
2. Press Amplitude > More (1 of 2) > User Flatness > Configure Cal Array > More (1 of 2) >
Preset List > Confirm Preset.
3. Press More (2 of 2) > Load/Store.
4. Ensure that the file FLATCAL1 is highlighted.
5. Press Load From Selected File > Confirm Load From File.
This populates the user flatness correction array with the data contained in the file FLATCAL1. The user
flatness correction array title displays User Flatness: FLATCAL1.
6. Press Return > Flatness Off On.
This applies the user flatness correction data contained in FLATCAL1.
Returning the Signal Generator to GPIB Listener Mode
During the user flatness correction process, the power meter is controlled by the signal generator via GPIB,
and no other controllers are allowed on the GPIB interface. The signal generator operates in GPIB talker
mode, as a device controller for the power meter. In this operating mode, it cannot receive SCPI commands
via GPIB.
NOTE
Before interfacing the signal generator to a remote controller, the signal generator must be
in GPIB listener mode. Press the GPIB Listener Mode softkey to return the signal generator to
GPIB listener mode from GPIB talker mode.
If an RF carrier has been previously configured, you must save the present instrument state
before returning the signal generator to GPIB listener mode.
1. Save your instrument state to the instrument state register.
For instructions, see “Saving an Instrument State” on page 71.
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Creating and Applying User Flatness Correction
2. Press GPIB Listener Mode.
This presets the signal generator and returns it to GPIB listener mode. The signal generator can now
receive remote commands executed by a remote controller connected to the GPIB interface.
3. Recall your instrument state from the instrument state register.
For instructions, see “Recalling an Instrument State” on page 72.
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Basic Operation
Using the Memory Catalog
Using the Memory Catalog
The signal generator’s interface for stored files is the memory catalog. From the memory catalog, you can
view, store, and save files using the signal generator’s front panel or a remote controller. For more
information on the memory catalog and performing these tasks remotely, see the E4428C/38C ESG SCPI
Command Reference and the E4428C/38C ESG Vector Signal Generator Programming Guide.
The memory catalog may contain the following file types and their associated data:
BIN
binary data
LIST
sweep data from the List Mode Values table including frequency, amplitude, and dwell
time
STAT
instrument state data (controlling instrument operating parameters, such as frequency,
amplitude, and mode)
UFLT
user flatness calibration correction pair data (user-defined frequency and corresponding
amplitude correction values)
NOTE
You may have additional file types depending on which options you have installed in your
signal generator.
Viewing Stored Files
1. Press Utility > Memory Catalog > Catalog Type.
All files in the memory catalog are listed in alphabetical order, regardless of which catalog type you
select. File information appears on the display and includes the file name, file type, file size, and the file
modification date and time.
2. Press List
The Catalog of List Files is displayed.
3. Press Catalog Type > State.
The Catalog of State Files is displayed.
4. Press Catalog Type > User Flatness.
The Catalog of USERFLAT Files is displayed.
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Using the Memory Catalog
Storing Files
To store a file to the memory catalog, first create a file. For this example, use the default list sweep table.
1. Press Preset.
2. Press Sweep/List > Configure L1ist Sweep > More (1 of 2) > Load/Store.
This opens the Catalog of List Files.
3. Press Store to File.
This displays a menu of alphabetical softkeys for naming the file. Store to: is displayed in the active
function area.
4. Enter the file name LIST1 using the alphabetical softkeys and the numeric keypad.
The maximum file name length is 23 characters (alphanumeric and special characters).
5. Press Enter.
The file is now displayed in the Catalog of List Files, showing the file name, file type, file size, and the
date and time the file was modified.
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Basic Operation
Using the Instrument State Registers
Using the Instrument State Registers
The instrument state memory is a section of memory divided into 10 sequences (numbered 0 through 9).
Each sequence consists of 100 registers (numbered 00 through 99). Instrument state sequences and registers
save and recall signal generator settings, and provide a quick way to reconfigure the signal generator when
switching between different instrument and signal configurations.
The signal generator with Option 005 (internal hard drive) has approximately 4 GB available for storing
instrument state files, as well as other user data. Without Option 005, the signal generator has 20 MB
available for data and instrument state storage. Instrument state files vary in length, depending on the signal
generator’s configuration.
Data, such as waveform files, arb settings, and table entries, are not stored in instrument state memory. Store
these data types to the signal generator’s memory. Instrument state memory only saves settings such as
frequency, attenuation, power, and so forth.
The following list shows additional signal generator settings that are not saved with the save operation.
FM Deviation
List Mode Freq
Hostname
FTP Server
RS-232 Baud Rate
List Mode Power
IP Address
Web Server (HTTP)
Remote Language
List Mode Dwell
Subnet Mask
Sockets SCPI (TELNET)
System Security Level
List Mode Sequence
Default Gateway
VXI-11 SCPI
System Security Level Display
Display State On/Off
MAC
System Security Level State
PM Deviation
Manual DHCP
Waveform data is stored in NVWFM. If you have a waveform file and want to save signal generator settings
associated with that file, you must first select the waveform in volatile waveform memory (WFM1). When
you save the signal generator settings associated with that file to instrument state memory, a reference to the
waveform file name will also be saved. Refer to “Storing and Loading Waveform Segments” on page 113
for information on saving waveform files.
For more information on storing file data, such as waveform files, arb setups, and table entries, refer to
“Storing Files” on page 69. Refer to the E4428C/38C ESG Signal Generator Programming Guide and the
E4428C/38C ESG Signal Generator Key and Data Field Reference for more information on the save and
recall function.
The following procedure demonstrates saving settings to the instrument state memory.
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Using the Instrument State Registers
Saving an Instrument State
1. Preset the signal generator, then turn on amplitude modulation (the AM annunciator will turn on):
a. Press Frequency > 800 > MHz.
b. Press Amplitude > 0 > dBm.
c. Press AM > AM Off On.
2. (Optional) If you want to associate these settings with a waveform file, load the waveform file into
WFM1 and select it. Refer to “Storing and Loading Waveform Segments” on page 113 for information
on loading waveform files into WFM1.
3. Press Save > Select Seq > 1 > Enter.
The sequence number becomes the active function. The signal generator displays the last sequence used.
Using the arrow keys, set the sequence to 1.
4. Press Select Reg > 1 > Enter.
The register number in sequence 1 becomes the active function. The signal generator displays either the
last register used accompanied by the text: (in use), or (if no registers are in use) register 00
accompanied by the text: (available). Use the arrow keys to select register 01.
5. Press Save Seq[1] Reg[01].
This saves the instrument state, configured in step 1, to sequence 1, register 01 of the instrument state
register. If a waveform is selected or being played, then the name of the waveform file will also be saved
in sequence 1, register 01 of the instrument state register.
6. Press Add Comment to Seq[1] Reg[01].
This enables you to add a descriptive comment to sequence 1 register 01. The comment appears in the
Saved States list when the Recall hardkey is pressed. If you have a waveform associated with the
instrument state, enter the name of the waveform in the comment field. You can then easily identify the
name of the waveform and associated instrument state when the Recall hardkey is pressed.
7. Using the letter softkeys, front panel knob, or numeric keypad, enter a comment and press Enter.
8. Press Edit Comment In Seq[1] Reg[01].
If you wish, you can now change the descriptive comment for sequence 1 register 01.
Changes to a previously saved instrument state, for example an instrument state saved in Seq n, Reg nn, can
be re-saved by highlighting that register and pressing Re-SAVE Seq[n] Reg[nn]. The re-save function
overwrites previously saved instrument state settings, with the new settings configuration.
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Using the Instrument State Registers
Recalling an Instrument State
Using this procedure, you will learn how to recall instrument settings saved to an instrument state register.
Refer to the “Recalling an Instrument State for a Waveform File” on page 73 for recalling a waveform file
and associated signal generator settings.
1. Press Preset.
2. Press the Recall hardkey.
Notice that the Select Seq softkey shows sequence 1. (This is the last sequence that you used.)
3. Press RECALL Reg.
The register to be recalled in sequence 1 becomes the active function. Press the up arrow key once to
select register 1. Your stored instrument state settings are recalled.
Saving an Instrument State for a Waveform File
This procedure applies to the E4438C with Option 001/601 or 002/602 and demonstrates saving signal
generator settings associated with a waveform file.
NOTE
The save function saves only a reference to a waveform file name; no waveform data is
stored. Use Save function to save signal generator settings and use the Store function to
save waveform data.
Signal generator settings such as frequency, power, attenuator level, and so forth, are not saved when a
waveform file is saved. Signal generator settings, associated with the waveform file, must be saved to the
instrument state memory. If there is no waveform file in NVWFM, create one using the procedure, “Creating
Waveform Segments” on page 108.
You can save signal generator settings, associated with a waveform file, so that when you load the waveform
from NVWFM and play it, the same signal generator settings can be recalled and re-applied to the waveform
file.
Set Up the Signal Generator
1. Press Preset.
2. Press Frequency > 2 > GHz.
3. Press Amplitude > – 30 > dBm.
4. Press Mode > Dual ARB > Waveform Segments.
5. Scroll and highlight a waveform file in NVWFM.
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6. Press Load Segment From NVWFM Memory > Return.
7. Scroll to the waveform selected in step 3.
8. Press Select Waveform > ARB Off On to on. This causes the signal generator to play the waveform.
Saving the Instrument State
Instrument states can be saved to any one of the 10 sequences and 100 registers in instrument state memory.
In this procedure, sequence 01 and register 02 are used to store the signal generator settings associated with
the waveform file. The Save function saves instrument settings and the waveform file name but does not
save waveform data. Waveform data can only be saved to NVWFM with the Store function.
1. Press Save > Select Seq > 01 > Select Reg > 02 > Save Reg.
The signal generator settings associated with the waveform file and the name of the waveform file are now
saved in the instrument state memory. The section “Recalling an Instrument State for a Waveform File” on
page 73 describes how to recall this instrument state and associated waveform file.
Recalling an Instrument State for a Waveform File
This procedure applies to signal generators with Option 001/601 or 002/602 and demonstrates recalling
signal generator settings associated with a waveform file. This procedure uses the same signal generator
settings and waveform file used in the previous section, “Saving an Instrument State for a Waveform File”.
1. Press Mode > Dual ARB > Waveform Segments.
2. Scroll and select the waveform file used in the previous section.
3. Press Load Segment From NVWFM Memory > Return > Select Waveform
4. Highlight the file selected in step 3.
5. Press Select Waveform.
The next step recalls the signal generator settings associated with the waveform file. These settings were
saved to Seq 01 and Reg 02 in the previous procedure.
6. Press Recall > Select Seq > 01
7. Press RECALL Reg > 01 > Enter.
The signal generator is now setup with the same settings associated with the waveform previously saved to
NVWFM.
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Basic Operation
Using the Instrument State Registers
Deleting Registers and Sequences
These procedures describe how to delete registers and sequences saved to an instrument state register.
Deleting a Specific Register within a Sequence
1. Press Preset.
2. Press the Recall or Save hardkey.
Notice that the Select Seq softkey shows the last sequence that you used.
3. Press Select Seq and enter the sequence number containing the register you want to delete.
4. Press Select Reg and enter the register number you want to delete.
Notice that the Delete Seq[n] Reg[nn] should be loaded with the sequence and register you want to delete.
5. Press Delete Seq[n] Reg[nn].
This deletes the chosen register.
Deleting All Registers within a Sequence
1. Press Preset.
2. Press the Recall or Save hardkey.
Notice that the Select Seq softkey shows the last sequence that you used.
3. Press Select Seq and enter the sequence number containing the registers you want to delete.
4. Press Delete all Regs in Seq[n].
This deletes all registers in the selected sequence.
Deleting All Sequences
CAUTION
Be sure you want to delete the contents of all registers and all sequences in the instrument
state register.
1. Press Preset.
2. Press the Recall or Save hardkey.
Notice that the Select Seq softkey shows the last sequence that you used.
3. Press Delete All Sequences.
This deletes all of the sequences saved in the instrument state register.
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Using Security Functions
CAUTION
Do not use the following functions with signal generator firmware revisions C.04.84,
C.04.86, or C.04.95:
•
Erase All
•
Erase and Sanitize All
•
Erase and Overwrite All
If you have one of the stated revisions installed, please upgrade immediately to firmware
revision C.04.96 or later.
This section describes how to use the ESG security functions to protect and remove classified proprietary
information stored or displayed in the instrument. All security functions described in this section also have
an equivalent SCPI command for remote operation. (Refer to the “System Subsystem (:SYSTem)” chapter
of the E4428C/38C ESG Signal Generators SCPI Command Reference for more information.)
Understanding Memory Types
The ESG comprises several memory types, each used for storing a specific type of data. Before removing
sensitive data, it is important to understand how each memory type is used in the signal generator. The
following tables describe each memory type used in the base instrument, optional baseband generator, and
optional hard disk.
Main
Memory
(SDRAM)
Data Retained
When Powered Off?
Memory Type
and Size
Base Instrument Memory
Writable During
Normal Operation?
Table 3-1
Purpose/Contents
Yes
No
firmware operating memory
Data Input Method
Location in Instrument and Remarks
operating system
(not user)
CPU board, not battery backed.
64 MB
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Main
Memory
(Flash)
Data Retained
When Powered Off?
Memory Type
and Size
Base Instrument Memory (Continued)
Writable During
Normal Operation?
Table 3-1
Yes
Yes
20 MB
Firmware
Memory
(Flash)
No
Yes
Purpose/Contents
Data Input Method
factory
firmware upgrades
calibration/configuration data and user-saved data
CPU board (same chip as firmware memory,
but managed separately)
user file system, which
includes instrument status
backup, flatness calibration,
IQ calibration, instrument
states, waveforms (including
header and marker data),
modulation definitions, and
sweep lists
User data is not stored in this memory if hard
disk (Option 005) is installed.
main firmware image
Because this 32-MB memory chip contains 20
MB of user data (described here) and 12 MB of
firmware memory, a selective chip erase is
performed. User data areas are selectively and
completely sanitized when you perform the
Erase and Sanitize function.
factory installed or
firmware upgrade
CPU board (same chip as main flash memory,
but managed separately)
front panel entry or
remotely
During normal operation, this memory cannot
be overwritten except for LAN configuration.
It is only overwritten during the firmware
installation or upgrade process.
12 MB
Yes
Yes
Location in Instrument and Remarks
LAN configuration
Because this 32-MB memory chip contains 20
MB of user data and 12 MB of firmware
memory (described here), a selective chip
erase is performed. User data areas are
selectively and completely sanitized when you
perform the Erase and Sanitize function.
Battery
Backed
Memory
(SRAM)
Yes
Yes
last instrument state, last
instrument state backup,
persistent instrument state
and instrument status
512 kB
Bootrom
Memory
(Flash)
128 kB
76
user-editable data (table
editors)
No
Yes
CPU bootup program and
firmware loader/updater
firmware operations CPU board
The battery can be removed to sanitize the
memory, but must be reinstalled for the
instrument to operate. The battery is located on
the motherboard.
factory programmed CPU board
During normal operation, this memory cannot
be overwritten or erased. This read-only data is
programmed at the factory.
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Basic Operation
Using Security Functions
Calibration
Backup
Memory
(Flash)
Data Retained
When Powered Off?
Memory Type
and Size
Base Instrument Memory (Continued)
Writable During
Normal Operation?
Table 3-1
No
Yes
Purpose/Contents
Data Input Method
factory
factory or service
calibration/configuration data only
backup
Location in Instrument and Remarks
motherboard
no user data
512 KB
Boards
Memory
(Flash)
No
Yes
factory calibration and
information files, code
images, and self-test limits
Yes
No
CPU data and instruction
cache
512 Bytes
Microprocessor
Cache
(SRAM)
factory or service
only
all RF boards, baseband generator, and
motherboard
no user data
memory is managed CPU board, not battery backed.
by CPU, not user
3 kB
Waveform
Memory
(SDRAM)
Data Retained
When Powered Off?
Memory Type
and Size
Baseband Generator Memory (Options 001/601 and 002/602)
Writable During
Normal Operation?
Table 3-2
Yes
No
waveforms (including
header and marker
data) and PRAM
normal user operation
No
Yes
firmware image for
baseband generator
firmware upgrade
Purpose/Contents
Data Input Method
Remarks
User data is completely sanitized when you
perform the Erase and Sanitize function. Not
battery backed.
40−320 MB
BBG
Firmware
Memory
(Flash)
32 MB
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Coprocessor
Memory
(SRAM)
Data Retained
When Powered Off?
Memory Type
and Size
Baseband Generator Memory (Options 001/601 and 002/602) (Continued)
Writable During
Normal Operation?
Table 3-2
Yes
No
operating memory of
baseband coprocessor
CPU
No
No
support buffer memory normal user operation
for ARB and real time
applications
Purpose/Contents
Data Input Method
During normal
This memory is used during normal baseband
operation, some user
generator operation. It is not directly accessible
information, such as
by the user. Not battery backed.
payload data, can
remain in the memory.
32 MB
Buffer
Memory
(SRAM)
Remarks
This memory is used during normal baseband
generator operation. It is not directly accessible
by the user. Not battery backed.
5 x 512 kB
Media
Storage
(Built-in
Hard Disk)
Data Retained
When Powered Off?
Memory Type
and Size
Hard Disk Memory (Option 005)
Writable During
Normal Operation?
Table 3-3
Yes
Yes
6 GB or
10 GB
(4 GB usable
in both cases)
Buffer
Memory
(DRAM)
No
No
Purpose/Contents
Data Input Method
Remarks
user files, including
flatness calibrations,
IQ calibration,
instrument states,
waveforms (including
header and marker
data), modulation
definitions, and sweep
lists
user-saved data
The magnetic residue requires several rewrite
cycles or drive removal and destruction.
The hard disk is an option and is therefore not
installed in some instruments. If it is installed,
these files are stored on the hard disk instead of
in flash memory.
User data is completely sanitized when you
perform the Erase and Sanitize function.
buffer (cache) memory normal operation
through hard disk
512 kB
Removing Sensitive Data from Memory
When moving the signal generator from a secure development environment, you can remove any classified
proprietary information stored in the instrument. This section describes several security functions you can
use to remove sensitive data from your instrument.
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Using Security Functions
Erase All
CAUTION
Do not use this function with signal generator firmware revisions C.04.84, C.04.86, or
C.04.95. If you have one of these revisions installed, please upgrade immediately to revision
C.04.96 or later.
This function removes all user files, user flatness calibrations, user I/Q calibrations, and resets all table
editors with original factory values, ensuring that user data and configurations are not accessible or
viewable. The instrument appears as if it is in its original factory state, however, the memory is not sanitized.
This action is relatively quick, taking less than one minute (the exact time depends on the number of files).
To carry out this function, press Utility > Memory Catalog > More (1 of 2) > Security > Erase All > Confirm Erase.
NOTE
This function is different than pressing Utility > Memory Catalog > More (1 of 2) >
Delete All Files, which deletes all user files, but does not reset the table editors.
Erase and Overwrite All
CAUTION
Do not use this function with signal generator firmware revisions C.04.84, C.04.86, or
C.04.95. If you have one of these revisions installed, please upgrade immediately to revision
C.04.96 or later.
This function performs the same actions as Erase All and then clears and overwrites the various memory
types in accordance with Department of Defense (DoD) standards, as described below.
SRAM
All addressable locations are overwritten with random characters.
CPU Flash
All addressable locations are overwritten with random characters and then the flash blocks are erased.
This accomplishes the same purpose of a chip erase, however, only the areas that are no longer in use are
erased and the factory calibration files are left intact. System files are restored after erase.
DRAM
All addressable locations are overwritten with random characters.
Hard Disk
All addressable locations are overwritten with a single character. (This is insufficient for top secret data,
according to DoD standards. For top secret data, the hard drive must be removed and destroyed.)
To carry out this function, press Utility > Memory Catalog > More (1 of 2) > Security > Erase and Overwrite All >
Confirm Overwrite.
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Erase and Sanitize All
CAUTION
Do not use this function with signal generator firmware revisions C.04.84, C.04.86, or
C.04.95. If you have one of these revisions installed, please upgrade immediately to revision
C.04.96 or later.
This function performs the same actions as Erase and Overwrite All and then adds more overwriting actions.
After executing this function, you must manually perform some additional steps for the sanitization to
comply with Department of Defense (DoD) standards. These actions and steps are described below.
SRAM
All addressable locations are overwritten with random characters.
DRAM
All addressable locations are overwritten with a single character. You must then power off the
instrument to purge the memory contents.
Hard Disk
All addressable locations are overwritten with a single character and then a random character. (This is
insufficient for top secret data, according to DoD standards. For top secret data, the hard drive must be
removed and destroyed.)
To carry out this function, press Utility > Memory Catalog > More (1 of 2) > Security > Erase and Sanitize All >
Confirm Sanitize.
Removing Persistent State Information Not Removed During Erase
Persistent State
The persistent state settings contain instrument setup information that can be toggled within predefined
limits such as display intensity, contrast and the GPIB address. In vector models, the user IQ Cal is also
saved in this area.
The following key presses or SCPI commands can be used to clear the IQ cal file and to set the operating
states that are not affected by a signal generator power-on, preset, or *RST command to their factory default:
Instrument Setup
•
•
On the front panel, press: Utility > Power On/Preset > Restore System Defaults > Confirm Restore Sys Defaults
Or send the command: :SYSTem:PRESet:PERSistent
LAN Setup
The LAN setup (hostname, IP address, subnet mask, and default gateway) information is not defaulted with a signal
generator power-on or *RST command. This information can only be changed or cleared by entering new data.
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User IQ Cal File (Vector Models Only)
When a user-defined IQ calibration has been performed, the cal file data is removed by setting the cal file to default, as
follows:
1. On the front panel, press: I/Q > I/Q Calibration > Revert to Default Cal Settings
2. Send these commands:
•
:CAL:IQ:DEF
•
:CAL:WBIQ:DEF
Using the Secure Mode
The secure mode automatically applies the selected Security Level action the next time the instrument’s
power is cycled.
Setting the Secure Mode Level
CAUTION
Do not use the functions Erase, Overwrite, or Sanitize with signal generator firmware
revisions C.04.84, C.04.86, or C.04.95. If you have one of these revisions installed, please
upgrade immediately to revision C.04.96 or later.
1. Press Utility > Memory Catalog > More (1 of 2) > Security > Security Level.
2. Choose from the following selections:
None − equivalent to a factory preset, no user information is lost
Erase − equivalent to Erase All
Overwrite − equivalent to Erase and Overwrite All
Sanitize − equivalent to Erase and Sanitize All
Activating the Secure Mode
CAUTION
Once you activate secure mode (by pressing Confirm), you cannot deactivate or decrease the
security level; the erasure actions for that security level execute at the next power cycle.
Once you activate secure mode, you can only increase the security level until you cycle
power. For example, you can change Erase to Overwrite, but not the reverse.
After the power cycle, the security level selection remains the same, but the secure mode is
not activated.
Press Utility > Memory Catalog > More (1 of 2) > Security > Enter Secure Mode > Confirm.
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The Enter Secure Mode softkey changes to Secure Mode Activated.
If Your Instrument is Not Functioning
If the instrument is not functioning and you are unable to use the security functions, you must physically
remove the processor board and optional hard disk, if installed, from the instrument. Once these assemblies
are removed, proceed as follows:
For the processor board, choose one of the following options:
•
Discard the processor board and send the instrument to a repair facility. A new processor board will be
installed and the instrument will be repaired and calibrated. If the instrument is still under warranty, you
will not be charged for the new processor board.
•
If you have another working instrument, install the processor board into that instrument and erase the
memory. Then reinstall the processor board back into the non-working instrument and send it to a repair
facility for repair and calibration. If you discover that the processor board does not function in the
working instrument, discard the processor board and note that it caused the instrument failure on the
repair order. If the instrument is still under warranty, you will not be charged for the new processor
board.
For the optional hard disk, choose one of the following options:
•
Discard the hard disk and send the instrument to a repair facility. Indicate on the repair order that the
hard disk was removed and must be replaced. A new hard disk will be installed and the instrument will
be repaired and calibrated. If the instrument is still under warranty, you will not be charged for the new
hard disk.
•
Keep the hard disk and send the instrument to a repair facility. When the instrument is returned, reinstall
the hard disk.
For procedures on removing and replacing the processor board and hard disk, refer to the E4428C/38C ESG
Signal Generators Service Guide.
Using the Secure Display
This function prevents unauthorized personnel from reading the instrument display and tampering with the
current configuration through the front panel. The display is blanked , except for the message *** SECURE
DISPLAY ACTIVATED *** (see Figure 3-6 on page 83), and the front panel keys are disabled. Once this
function is activated, the power must be cycled to re-enable the display and front panel keys.
To apply this function, press Utility > Display > More (1 of 2) > Activate Secure Display > Confirm Secure Display
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Using Security Functions
Figure 3-6
Chapter 3
ESG Screen with Secure Display Activated
83
Basic Operation
Enabling Options (E4438C Only)
Enabling Options (E4438C Only)
You can retrofit a signal generator after purchase to add new capabilities. Some new optional features are
implemented in hardware that you must install. Some options are implemented in software but require the
presence of optional hardware in the instrument. This example shows you how to enable software options.
Enabling a Software Option
A license key (provided on the license key certificate) is required to enable each software option.
1. Access the Software Options menu:
Utility > Instrument Adjustments > Instrument Options > Software Options
The following is an example of the signal generator display, which lists any enabled software options,
and the software options that can be enabled:
2. Verify that the host ID shown on the display matches the host ID on the license key certificate.
The host ID is unique for each instrument. If the host ID on the license key certificate does not match
your instrument, the license key cannot enable the software option.
3. Verify that any required hardware is installed. Software options are linked to specific hardware options,
so before a software option can be enabled, the appropriate hardware option must be installed. For
example, Option 400, W-CDMA, requires Option 001/601 or 002/602, Internal Baseband Generator. If
the software option that you intend to install is listed in a grey font, the required hardware may not be
installed (in the Hardware Options menu, look for an X in the “Selected” column of the appropriate
hardware option).
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4. Enable the software option:
a. Highlight the desired option.
b. Press Modify License Key, and enter the 12-character license key (from the license key certificate).
c. Verify that you want to reconfigure the signal generator with the new option:
Proceed With Reconfiguration > Confirm Change
The instrument enables the option and reboots.
Using the Web Server
You can communicate with the signal generator using the Web Server. This service uses TCP/IP
(Transmission Control Protocol/Internet Protocol) to communicate with the signal generator over the
internet.
The Web Server uses a client/server model where the client is the web browser on your PC or workstation
and the server is the signal generator. When you enable the Web Server, you can access a web page that
resides on the signal generator.
The Web-Enabled ESG web page, shown in Figure 3-7, provides general information on your signal
generator and a means to control the instrument by using a remote front panel interface or using SCPI
(Standard Communication for Programmable Instruments) commands. The web page also has links to
Agilent’s products, support, manuals, and website.
NOTE
The Web Server service is compatible with the latest version of the Microsoft© Internet
Explorer web browser.1
The Signal Generator Web Control menu button on the Web-Enabled ESG web page will access a second
web page. This web page, shown in Figure 3-8, provides a virtual instrument interface that can be used to
control the signal generator. You can use the mouse to click on the signal generator’s front panel hardkeys,
softkeys and number pad. There is also a text box that can be used to send SCPI commands to the
instrument.
Activating the Web Server
Perform the following steps to access the Web Server.
1. Turn on the Web Server by pressing Utility > GPIB/RS–232 LAN > LAN Services Setup > Web Server On.
1. Microsoft is a registered trademark of Microsoft Corp.
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2. Press the Proceed With Reconfiguration softkey.
3. Press the Confirm Change (Instrument will Reboot) softkey. The signal generator will reboot.
4. Launch your PC or workstation web browser.
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5. Enter the IP address of the signal generator in the web browser address field. For example,
http://101.101.101.101. Replace 101.101.101.101 with your signal generator’s IP address. Press the
Enter key on the computer’s keyboard.
NOTE
The IP (Internet Protocol) address can change depending on your LAN configuration.
Use the LAN Config Manual DHCP softkey to select a Manual or DHCP (dynamic host
communication protocol) LAN configuration. Refer to E4428C/38C ESG Signal Generator
Key and Data Field Reference for more information.
6. Press the enter key on the computer’s keyboard. The web browser will display the signal generator’s
homepage as shown below in Figure 3-7. This web page displays information about the signal generator
and provides access to Agilent’s website.
Figure 3-7
Chapter 3
Signal Generator Web Page
87
Basic Operation
Using the Web Server
7. Click the Signal Generator Web Control menu button on the left of the page. A new web page will be
displayed as shown below in Figure 3-8.
Figure 3-8
Web Page Front Panel
This web page remotely accesses all signal generator functions and operations. Use the mouse pointer to
click on the signal generator’s hardkeys and softkeys. The results of each mouse click selection will be
displayed on the web page. For example, click on the Frequency hardkey then use the front panel key pad to
enter a frequency. You can also use the up and down arrow keys to increase or decrease the frequency.
You can use the SCPI Command text box at the bottom of the front panel display to send commands to the
signal generator. Enter a valid SCPI command, then click the SEND button. The results of the command will
be displayed on a separate web page titled, “SCPI Command Processed”. You can continue using this web
page to enter SCPI commands or you can return to the front panel web page.
NOTE
88
It may be necessary to use the web browser Refresh function if the web page does not
update with new settings.
Chapter 3
4
Basic Digital Operation (Option 001/601 or
002/602)
The following list shows the topics covered in this chapter:
•
“Custom Modulation” on page 91
•
“Arbitrary (ARB) Waveform File Headers” on page 93
•
“Using the Dual ARB Waveform Player” on page 107
•
“Understanding the I/Q Modulator Filter” on page 115
•
“Local Settings for ARB Waveform Formats and the Dual ARB Player” on page 117
•
“Using Waveform Markers” on page 124
•
“Triggering Waveforms” on page 140
•
“Using Waveform Clipping” on page 149
•
“Using Waveform Scaling” on page 157
•
“Using Customized Burst Shape Curves” on page 161
•
“Using Finite Impulse Response (FIR) Filters” on page 168
•
“Modifying a FIR Filter Using the FIR Table Editor” on page 173
•
“Differential Encoding” on page 175
•
“User-Defined I/Q Maps” on page 183
•
“User-Defined FSK Modulation” on page 187
•
“Creating and Using Bit Files” on page 190
•
“Waveform Licensing for Firmware Version ³ C.05.23” on page 195
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Basic Digital Operation (Option 001/601 or 002/602)
•
“Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version < C.05.23” on page 197
•
“Waveform Licenses (Signal Studio “A” Versions)” on page 203
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Custom Modulation
Custom Modulation
For creating custom modulation, the signal generator offers two modes of operation: the ARB waveform
generator mode and the real time I/Q baseband mode. The ARB waveform generator mode has built-in
modulation formats such as NADC or GSM and pre-defined modulation types such as BPSK and 16QAM
that can be used to create a signal. The real time I/Q baseband mode can be used to create custom data
formats using built-in PN sequences or custom-user files along with various modulation types and different
built-in filters such as Gaussian or Nyquist.
Both modes of operation are used to build complex, digitally modulated signals that simulate
communication standards with the flexibility to modify existing digital formats, define or create digitally
modulated signals, and add signal impairments.
Custom ARB Waveform Generator
The signal generator’s ARB waveform generator mode is designed for out-of-channel test applications. This
mode can be used to generate data formats that simulate random communication traffic and can be used as a
stimulus for component testing. Other capabilities of the ARB waveform generator mode include:
•
configuring single or multicarrier signals (up to 100 carriers)
•
creating waveform files using the signal generator’s front panel interface
The waveform files, when created as random data, can be used as a stimulus for component testing where
device performance such as adjacent channel power (ACP) can be measured. The AUTOGEN_WAVEFORM
file, that is automatically created when you turn the ARB waveform generator on, can be renamed and stored
in the signal generator’s non-volatile memory. This file can later be loaded into volatile memory and played
using the dual ARB waveform player.
For more information, refer to the sections “Using the Dual ARB Waveform Player” on page 107 and
“Modes of Operation” on page 24.
Chapter 4
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Basic Digital Operation (Option 001/601 or 002/602)
Custom Modulation
Custom Real Time I/Q Baseband
The real time mode simulates single-channel communication using user-defined modulation types along
with custom FIR filters, and symbol rates. Data can be downloaded from an external source into PRAM
memory or supplied as real time data using an external input. The real time I/Q baseband mode can also
generate pre-defined data formats such as PN9 or FIX4. A continuous data stream generated in this mode
can be used for receiver bit error analysis. This mode is limited to a single carrier. The real time I/Q
baseband mode:
• has more data and modulation types available than the ARB waveform generator mode
• supports custom I/Q constellation formats
• has the capability to generate continuous PN sequences for bit error rate testing (BERT)
• needs no waveform build time when signal parameters are changed.
For more information, refer to the custom arb section “Using the Arbitrary Waveform Generator” on page
384, the custom real time section “Using the Real Time I/Q Baseband Generator” on page 390 and the
section on “Digital Modulation” on page 24.
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Arbitrary (ARB) Waveform File Headers
Arbitrary (ARB) Waveform File Headers
ARB file headers are used to save a modulation format’s signal generator settings and parameters so that the
waveform can be replicated when it is again played back by the dual ARB player. Once a modulation format,
such as Custom real time, has been turned off, the waveform file is available only to the dual ARB player.
File header settings and parameters can be defined and saved along with the waveform file in the signal
generator’s non-volatile waveform memory (NVWFM). When you load a stored waveform file into volatile
waveform memory (WFM1), the file header information will be used to configure the ESG so that the dual
ARB player is set up the same way each time that the waveform file is played.
A default file header is automatically created whenever a waveform is generated (turning on a modulation
format), a waveform sequence created, or a waveform file downloaded to the ESG (Refer to the
E4428C/38C ESG Signal Generators Programming Guide for details on downloading files).
The following ESG setting and parameter information can be saved to the file header:
•
ARB sample clock rate
•
Runtime scaling (only in the dual ARB player)
•
Marker 1–4 settings and routing functions (page 124)
— Polarity
— ALC hold
— RF blanking
•
High crest mode (only in the dual ARB player)
•
Modulator attenuation
•
Modulator filter
•
I/Q output filter (used when routing signals to the rear panel I/Q outputs)
•
Other instrument optimization settings (for files generated by the ESG) that cannot be set by the user.
File headers can also store a user-defined 32-character text description of the waveform or sequence file. For
details on the file header settings and parameters, refer to “File Header Description” on page 96.
Creating a File Header
When you turn a modulation format on, the ESG automatically generates a temporary waveform file along
with a default marker file and default file header. The temporary waveform file resides in volatile waveform
memory (WFM1) and is named AUTOGEN_WAVEFORM. The default file header has no signal generator
settings saved to it and the default marker file consists of all zeros. Refer to the E4428C/38C ESG Signal
Chapter 4
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Basic Digital Operation (Option 001/601 or 002/602)
Arbitrary (ARB) Waveform File Headers
Generators Programming Guide for more information on marker files.
When you turn the modulation format off, the AUTOGEN_WAVEFORM file remains in volatile waveform
memory (WFM1) and can be selected again for playing only by the dual ARB player. If you turn on another
Arb modulation format or change ESG parameters and settings, the AUTOGEN_WAVEFORM file will be
overwritten by a new AUTOGEN_WAVEFORM, file header, and marker file.
If you want to keep the configuration setup in the AUTOGEN_WAVEFORM file, save it, using a different name,
to NVWFM. The associated file header and marker file will automatically be saved. For information on
storing files after the modulation format is turned off, see “Storing Waveform Segments to Non-Volatile
Memory” on page 113.
NOTE
Each time an ARB modulation format is turned on, a new AUTOGEN_WAVEFORM along with
a default marker and default file header are generated which overwrites the previous
AUTOGEN_WAVEFORM file, marker file and file header.
When the waveform file is stored to non-volatile memory (NVWFM), the associated file header information
is automatically saved to the signal generator’s /USER/HEADER directory and the marker file is
automatically saved to the signal generator’s /USER/MARKERS directory. When a waveform file, residing
in WFM1, is selected for playback, the file header settings along with the marker file settings are
automatically applied to the ESG.
The following procedure will generate an AUTOGEN_WAVEFORM file and file header using the ARB
CDMA2000 modulation format. This procedure for generating an AUTOGEN_WAVEFORM file and file header
applies to all the Arb formats.
1. Turn on the ESG and then press Preset.
2. Press Mode > CDMA > Arb CDMA2000 > CDMA2000 Off On to On. See Figure 4-1 below.
The ESG creates the AUTOGEN_WAVEFORM file along with a default file header and default marker file when
the modulation format, CDMA2000 in this example, is turned on. At this time, the file header does not have
signal generator settings or parameters for the currently playing AUTOGEN_WAVEFORM file. You must
modify the default file header settings and parameters for the active modulation and then save the file header
information using the Save Setup To Header softkey.
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Figure 4-1
First-Level Softkey Menu
First-Level Softkey
Menu
Not all ARB formats
have a Second Page
Modifying Header Information
This procedure builds on the previous procedure, explaining the different fields of a file header, and showing
how to access, modify, and save changes to the file header information.
In a modulation format, you can access a file header only while the modulation format is active (on). All
ARB modulation formats and the dual ARB player access the file header the same way, except that in some
modulation formats, the menu may be on page two of the first-level softkey menu.
1. From the first-level softkey menu (shown in Figure 4-1), open the Header Utilities menu:
Press More (1 of 2) > ARB Setup > Header Utilities
Figure 4-2 on page 96 shows the default file header for the AUTOGEN_WAVEFORM CDMA2000 digital
modulation waveform. The Header Field column names the parameters for the file header. The
Saved Header Settings column, shows that the signal generator settings for the active format are
Unspecified, meaning that no settings have been saved to the file header.
The Current Inst. Settings column shows the current signal generator settings for the active
modulation. These settings become the saved header settings when they are saved to the file header (as
demonstrated in Step ).
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Figure 4-2
CDMA2000 Default Header Display
Lets you Enter/Edit the
Description Field
Clears the Saved Header
Settings Column to Default
Settings
Saves the Current Inst.
Settings Column to the
Saved Header Settings
Column
Current Signal Generator
Settings
Page 1
Page 2
Default Header Settings
NOTE
If a setting is unspecified in the file header, the signal generator’s current value for that
setting does not change when you select and play the waveform in the future.
2. Save the information in the Current Inst. Settings column to the file header:
Press Save Setup To Header.
Both the Saved Header Settings column and the Current Inst. Settings column now
display the same settings; the Saved Header Settings column lists the settings saved in the file
header.
File Header Description
The file header contains the following information:
96
32-Character
Description:
A description entered for the header, such as a the waveform’s function (saved/edited with
the Edit Description softkey, see Figure 4-2). You can use the displayed alpha/symbol
softkeys and the numeric keypad to enter information.
Sample Rate:
The ARB sample clock rate.
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Runtime Scaling:
The Runtime scaling value. Runtime scaling is applied in real time while the waveform is
playing. This setting can be changed only for files playing in the dual ARB player.
Marker 1...4 Polarity: The marker polarity, positive or negative (described on page 139).
ALC Hold Routing:
Which marker, if any, implements the ESG’s ALC hold function (described on page 126).
The ALC hold function holds the ALC at its current level when the marker signal is low.
All waveforms generated in the ESG have a marker on the first sample point. In order to
see the results from the three routing selections, you may need to select a range of sample
(marker) points. Setting the marker points is accomplished using the Set Marker on Range
of Points softkey located in the Marker Utilities softkey menu. See “Setting Marker Points
in a Waveform Segment” on page 132 for more information.
Alt Ampl. Routing
This will display which marker, if any, triggers the ESG’s alternate amplitude feature when
the marker signal is low. When the marker signal goes high, the trigger is terminated,
disengaging alternate amplitude. You still need to configure the alternate amplitude
parameters located in the Amplitude hardkey menu.
RF Blank Routing:
Which marker, if any, implements the ESG’s RF blanking function (described on page
137) when the marker signal is low. RF blanking also uses ALC hold. There is no need to
select the ALC Hold Routing for the same marker when you are using the RF Blank
Routing function. When the marker signal goes high, RF blanking is discontinued.
High Crest Mode
This field displays the status of the high crest mode for the dual ARB player. The high crest
mode reduces ALC levels while playing ARB waveform files, resulting in the maximum
output level but reducing power level accuracy. This setting can only be changed for files
in the dual ARB player.
Mod Attenuation:
The I/Q modulator attenuation setting.
I/Q Mod Filter:
The I/Q modulator filter setting. The modulator filter affects the I/Q signal modulated onto
the RF carrier.
I/Q Output Filter:
The I/Q output filter setting. The I/Q output filter is used for I/Q signals routed to the rear
panel I and Q outputs.
3. Return to the ARB Setup menu: Press Return.
You are now in the ARB Setup softkey menu. From this menu you can access all the signal generator
settings that are saved to the file header. However, not all ESG settings are saved to the file header. For
example, the ARB Reference Ext Int softkey selection is not part of the saved header settings. Figure 4-3
shows the ARB Setup softkey menu and the softkey paths used in steps four through nine.
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Figure 4-3
ARB Setup Softkey Menu and Marker Utilities
*
* Opt 403 Dual ARB Player softkey
Dual ARB
Player Softkeys
(They do not Appear
in other Arb Formats)
4. Set the ARB sample clock to 5 MHz: Press ARB Sample Clock > 5 > MHz.
5. Set the modulator attenuation to 15 dB:
Press More (1 of 2) > Modulator Atten n.nn dB Manual Auto to Manual > 15 > dB.
6. Set the I/Q modulation filter to a through:
Press I/Q Mod Filter Manual Auto to Manual > Through.
7. Set marker one to blank the RF output at the set marker point(s):
Press More (2 of 2) > Marker Utilities > Marker Routing > Pulse/RF Blank > Marker 1.
For information on setting markers, see “Using Waveform Markers” on page 124.
8. Set the polarity of Marker 1 negative:
Press Return > Marker Polarity > Marker 1 Polarity Neg Pos to Neg.
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9. Return to the Header Utilities menu: Press Return > Return > Header Utilities.
Notice that the Current Inst. Settings column now reflects the changes made in steps 4 through
8 to the current signal generator setup, but that the saved header values have not changed (as shown in
Figure 4-4 below).
Figure 4-4
Differing Values between Header and Current Setting Columns
Values Differ between the
two Columns
Page 1
Values Differ between the
two Columns
Page 2
10. Save the current settings to the file header: Press the Save Setup To Header softkey.
The settings from the Current Inst. Settings column now appear in the Saved Header
Settings column. The file header has been modified and the current instrument settings saved. This is
shown in Figure 4-5.
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Figure 4-5
Saved File Header Changes
Page 1
Page 2
While a modulation format is active (on), the AUTOGEN_WAVEFORM waveform file plays and you can
modify the header information. Once you turn the modulation format off, the header information is available
only through the dual ARB player.
NOTE
100
If you turn the modulation format off and then on, you overwrite the previous
AUTOGEN_WAVEFORM file and its file header. To avoid this, rename the file before you turn
the modulation format back on (see “Storing Waveform Segments to Non-Volatile
Memory” on page 113).
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Dual ARB Player Waveform Sequence File Headers
When you create a waveform sequence (described on page 109), the ESG automatically creates a default
file header, which takes priority over the headers for the waveform segments that compose the waveform
sequence. During a waveform sequence playback, the waveform segment headers are ignored (except to
verify that all required options are installed). When you store the waveform sequence, its file header is
stored with it.
Follow the procedure “Creating a Waveform Sequence” on page 109 to generate a waveform sequence file
header.
Editing and Viewing File Headers in the Dual ARB Player
Before you can edit a file header in the dual ARB player, the associated waveform file must reside in volatile
waveform memory (WFM1). In addition, you cannot edit the AUTOGEN_WAVEFORM file header in the dual
ARB player if the AUTOGEN_WAVEFORM file is currently being played by another modulation format such
as Custom real time. Turn off the modulation format then play the AUTOGEN_WAVEFORM file using the dual
ARB player. You can then modify the file header.
If you want to edit a file header for a waveform file that resides in non-volatile memory (NVWFM), move it
to WFM1 and then play it. Refer to “Loading Waveform Segments from Non-Volatile Memory” on page 114
for information on loading files from NVWFM.
Edits to file headers can only be performed when the waveform file is playing. After making changes to the
signal generator settings and parameters, you can apply these new settings to the waveform by pressing the
Save Setup To Header softkey and then reselecting the waveform file for playback. When you do this, you will
see the values from the Saved Header Settings column overwrite the settings in the Current Inst.
Settings column. For information on selecting and playing waveform files, see “Playing a Waveform
Sequence” on page 110.
NOTE
Edits to file headers can only be performed when the waveform file is playing.
Modifying File Header Information
All file header descriptions listed in the procedure “Modifying Header Information” on page 95 are valid in
the dual ARB player. The following procedure selects a waveform file, accesses its file header, and then
refers you back to the aforementioned procedure to perform the edits. This procedure assumes there is an a
user-defined waveform file or an AUTOGEN_WAVEFORM file in WFM1. For information on creating the
AUTOGEN_WAVEFORM file and associated file header, refer to “Creating a File Header” on page 93.
1. Press Mode > Dual ARB > Select Waveform.
2. Using the arrow keys, highlight the waveform file that needs its file header edited.
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3. Press the Select Waveform softkey.
4. Press ARB Off On to On.
5. Press ARB Setup > Header Utilities.
6. Edit the file header.
a. If you have a default file header, go to “Modifying Header Information” on page 95, read the
additional information for step one, and then perform the rest of the steps in the procedure.
b. If you need to edit an existing file header, start with step three in the “Modifying Header
Information” procedure on page 95.
Viewing the file header with the Dual ARB Player Off
One of the differences between the dual ARB player and other Arb formats is that you can view a file header
without the dual ARB being on (ARB Off On softkey set to Off). However, you cannot edit the displayed file
header. This was done to prevent an accidental change to a file header for an AUTOGEN_WAVEFORM file that
may be playing in a modulation format. With the dual ARB player turned off, perform the following steps.
1. Press Mode > Dual ARB > Select Waveform.
2. Using the arrow keys, highlight the desired waveform file.
3. Press the Select Waveform softkey.
4. Press ARB Setup > Header Utilities.
The file header is displayed in the ESG display and you can see that the file header editing softkeys are
grayed-out (inactive) as shown in Figure 4-6 on page 103.
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Figure 4-6
Viewing a File Header
Header Editing Softkeys
Grayed-Out
file header and Current
Signal Generator Settings
Page 1
Page 2
Viewing a Different File Header
You can view file headers for other waveform files, even while the dual ARB player has a waveform
playing. However, you can edit a file header only when the associated waveform file is being played by the
dual ARB player. When you select another file header for viewing, the header editing softkeys are
grayed-out as shown in Figure 4-6.
This procedure will guide you through the available viewing choices.
1. Press Mode > Dual ARB > ARB Setup > Header Utilities > View Different Header
Notice that the waveform files in the table are listed in alphabetical order.
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Figure 4-7
Waveform File List for Viewing a Different Header
Current Waveform File
Type
Table
2. Press the Catalog Type softkey.
Now you have a choice of three waveform file types that can be displayed in the table accessed in step
one. These choices are shown in Figure 4-8.
104
Figure 4-8
Waveform File Type Selection
NVWFM
This choice will display all of the waveform segments currently stored in
non-volatile memory.
Seq
This choice will display all of the waveform sequence files.
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WFM1
This choice will display all of the waveform segments that currently reside in
volatile memory.
3. Press the NVWFM softkey.
After pressing the softkey, you are returned to the waveform file listing table that now displays the
waveform files from non-volatile memory. This is shown in Figure 4-9.
Figure 4-9
NVWFM Waveform Files Showing
Current Waveform File
Type
Table
4. Highlight a waveform file.
5. Press the View Header softkey.
The file header for the selected waveform file is shown in the ESG display. If there was a waveform playing,
its header information is removed from the ESG display, but its settings are still used by the signal generator.
There are two ways to return to the header information for the playing waveform. One way is to press the
View Different Header, select the current playing waveform file, and press View Header. The second way is to
press Return and then Header Utilities.
Playing a Waveform File containing a Header
After a waveform file (AUTOGEN_WAVEFORM) has been generated by a modulation format and the format is
turned off, the AUTOGEN_WAVEFORM file is accessible to and can be played back only in the dual ARB
player. This is also true for downloaded waveform files.
The file header settings, associated with the waveform file, are used to configure signal generator settings
and parameters when the waveform is selected for playback in the dual ARB. Some of these settings will
appear as part of the softkey labels. In addition, some of the saved header settings will appear on the dual
ARB summary display. This is shown in Figure 4-10 on page 106. Follow the procedure “Playing a
Waveform Sequence” on page 110 to apply file header settings and to play back a waveform.
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Figure 4-10
File Header Settings Applied
Waveform is not Selected Preset Settings Applied
Can change when a
Waveform is Selected
Summary Display
Waveform Selected Saved Header Settings Applied
Header Setting Applied
Header Setting same as
Preset
Summary Display
If you change any of the signal generator settings listed in the file header after the waveform file is selected,
the changed setting(s) will appear in the file header’s Current Inst. Settings column and they will be
applied to the signal generator instead of the saved header settings. To reapply the saved header settings,
reselect the waveform for playback.
NOTE
106
The signal generator used to play back a stored waveform file must have the same options
as are required to generate the file.
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Using the Dual ARB Waveform Player
The dual arbitrary (ARB) waveform player is used to play back waveform files. There are two types of
waveform files: segments and sequences. A segment is a waveform file that is created using one of the
signal generator’s pre-defined ARB formats (Custom, W-CDMA, CDMA2000, etc.). A sequence can be
described as several segments strung together to create one waveform file. Waveform files can also be
created remotely using another signal generator or using computer programs and downloaded to the ESG for
playback by the dual ARB waveform player. For information on downloading waveforms, refer to the
E4428C/38C ESG Signal Generator Programming Guide. The dual ARB player is used to rename and store
waveform files and to load waveform files from the signal generator’s memory.
A waveform file is automatically generated whenever an ARB modulation format is turned on. This
automatically generated file is named AUTOGEN_WAVEFORM. Because this default file name is shared among
all ARB formats, it must be renamed if you want to save the information contained in the file. If the file is
not renamed, it will be overwritten when another ARB format is turned on.
Before you can play or edit any waveform file, it must reside in volatile waveform memory. The signal
generator has two types of memory, WFM1 (volatile waveform memory) and NVWFM (non-volatile
waveform memory). Load a stored waveform file from NVWFM into volatile memory (WFM1) where it
can be edited or played by the ARB waveform player.
The dual ARB waveform player provides markers (page 124), triggering (page 140), and clipping (page
149) capabilities.
Accessing the Dual ARB Player
Press Mode > Dual ARB.
The first-level softkey menu is shown in the following figure. Most procedures start from this menu.
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Creating Waveform Segments
There are two ways to provide waveform segments for use by the waveform sequencer. You can either
download a waveform via the remote interface, or generate a waveform using one of the Arb modulation
formats. For information on downloading waveforms via the remote interface, see the E4428C/38C ESG
Signal Generator Programming Guide.
The following procedure describes how to create waveform segments using IS-95A CDMA waveforms. In
this procedure, you generate two IS-95A CDMA waveforms, a predefined 64 channel forward CDMA state
and a predefined 9 channel forward CDMA state. After the two waveform segments are named and stored in
memory, they are used to build a waveform sequence in the procedure, “Creating a Waveform Sequence” on
page 109.
1. Generate the first waveform:
Press Preset .
Press Mode > CDMA > Arb IS-95A.
Press Setup Select > 64 Ch Fwd.
Press CDMA Off On until On is highlighted.
This generates a waveform named AUTOGEN_WAVEFORM with the predefined 64 channel forward
link CDMA configuration. The 64 channel forward link AUTOGEN_WAVEFORM is stored in volatile
waveform memory (WFM1). During waveform generation, the CDMA and I/Q annunciators are
shown on the ESG’s front panel display.
e. Press CDMA Off On until Off is highlighted.
The AUTOGEN_WAVEFORM file is in use while the ARB modulation format is on; preventing you
from performing the modifications to the file as required in the following steps. When the
modulation format is turned off the AUTOGEN_WAVEFORM file remains in WFM1 and can be
modified and saved using a different file name.
a.
b.
c.
d.
2. Create the first waveform segment.
The AUTOGEN_WAVEFORM, created in the previous step, will be renamed and become the first waveform
segment.
a.
b.
c.
d.
NOTE
108
Press Mode > Dual ARB > Waveform Segments > Load Store to Store.
Highlight the default AUTOGEN_WAVEFORM file using the front panel arrow keys.
Press Rename Segment > Editing Keys > Clear Text.
Enter a file name (for example, FWDCH_64), and press Enter > Store Segment To NVWFM Memory.
This renames the waveform segment, and stores a copy in non-volatile memory (NVWFM).
Because there can be only one AUTOGEN_WAVEFORM waveform in WFM1 at any given
time, you must rename this file to clear the way for a second waveform.
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3. Generate the second waveform:
a.
b.
c.
d.
Press Mode > CDMA > Arb IS-95A.
Press Setup Select > 9 Ch Fwd.
Press CDMA Off On until On is highlighted.
Press CDMA Off On until Off is highlighted.
4. Create the second waveform segment:
Repeat Step 2, giving this segment a different descriptive name (for example, FWDCH_9).
Creating a Waveform Sequence
A waveform sequence is made up of segments but can also contain other sequences. Any number of
segments, up to 32768, can be used to create a sequence. This limit count is determined by the number of
segments in the waveform sequence. Segments and sequences can be repeated within a waveform sequence
and the total of all segments and repeated segments cannot exceed the limit count. Figure 4-11shows a
waveform sequence made up of two sequences and three segments. In this example the segment count is
eleven.
Figure 4-11
Waveform Sequence Diagram
Building a Waveform Sequence
The following procedure shows how to create, edit, and store a waveform sequence using the two waveform
segments created in the section “Creating Waveform Segments” on page 108. This procedure assumes that
the waveform segments FWDCH_64 and FWDCH_9 are present in WFM1. To use a segment in a sequence, the
segment must reside in volatile memory; for information on loading waveform segments from non-volatile
to volatile memory, see page 114.
1. Select the waveform segments:
Define a sequence as one repetition of the FWDCH_64 segment followed by one repetition of the
FWDCH_9 waveform segment.
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a. Press Mode > Dual ARB > Waveform Sequences > Build New Waveform Sequence > Insert Waveform.
b. Highlight the FWDCH_64 waveform segment and press Insert Selected Waveform.
c. Highlight the FWDCH_9 waveform segment and press Insert Selected Waveform.
d. Press Done Inserting
2. Optional: Enable markers as desired for the segments in the new sequence: see page 134.
3. Name and store the waveform sequence to the Catalog of Seq Files in the memory catalog:
a. Press Name and Store.
b. Enter a file name (for example, FWDCH_64+FWDCH_9).
c. Press Enter.
Playing a Waveform Sequence
You can play a waveform sequence or a waveform segment using this procedure. Both waveform types use
the same process.
If you have not created waveform segments and used them to build and store a waveform sequence,
complete the steps in the previous procedures, “Creating Waveform Segments” on page 108 and “Creating a
Waveform Sequence” on page 109.
NOTE
A waveform segment must reside in volatile memory (WFM1) before it can be played
individually or as part of a waveform sequence. Refer to “Loading Waveform Segments
from Non-Volatile Memory” on page 114 for more information.
1. Select a waveform sequence:
a. Press Mode > Dual ARB > Select Waveform.
b. Highlight a waveform sequence (for this example, FWDCH_64+FWDCH_9) from the Sequence
column of the Select Waveform catalog, and press Select Waveform.
The display shows the currently selected waveform (for example, Selected Waveform:
SEQ:FWDCH_64+FWDCH_9).
2. Generate the waveform:
Press ARB Off On to On.
This plays the waveform sequence created in the previous procedures. During the waveform sequence
generation, the ARB and I/Q annunciator are displayed. The waveform is now modulating the RF carrier.
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3. Configure the RF Output:
a. Set the RF carrier frequency.
b. Set the RF output amplitude.
c. Turn on the RF output.
The waveform sequence is now available at the signal generator’s RF OUTPUT connector.
Editing a Waveform Sequence
This procedure shows how to edit waveform segments within a waveform sequence, and then save the
edited sequence with the segment changes. Within the editing display, you can change the number of times
each segment plays (repetitions), delete segments from a sequence, add segments to a sequence, toggle
markers on and off (described on page 134), and save changes. There are two ways to save changes, they
can be saved to the current waveform sequence or they can be saved using a different waveform sequence
name.
NOTE
If you do not store changes to the waveform sequence before exiting the waveform
sequence editing display, changes will not be made.
Modifying the Sequence
1. Press Waveform Sequences.
2. Highlight the waveform sequence (for example, FWDCH_64+FWDCH_9.
3. Press Edit Selected Waveform Sequence.
4. Highlight the first waveform entry (for example, WFM1:FWDCH_64).
5. Press Edit Repetitions > 100 > Enter.
The number of repetitions for the first waveform entry changes to 100 and the cursor moves to the next
entry.
6. Press Edit Repetitions > 200 > Enter.
You have now changed the number of repetitions for each waveform segment entry from 1 to 100 and 200,
respectively. The following procedures show how to save these changes.
Saving Changes to the Current Sequence Name
Press Name and Store > Enter
You have now changed the number of repetitions for each waveform segment entry from 1 to 100 and 200,
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respectively. The sequence with the changes is stored under the same name to the Catalog of Seq
Files in the signal generator’s memory catalog.
Saving Changes to a Different Sequence Name
1. Press Name and Store.
2. Press Editing Keys > Clear Text.
3. Enter a file name (for example, CH64_100+CH9_200) using the alpha/symbol softkeys and the numeric
keypad.
4. Press Enter.
A new waveform sequence, CH64_100+CH9_200 is now defined based on the original sequence. It is a
copy of the original sequence, FWDCH_64+FWDCH_9.
Adding Real Time Noise to a Dual ARB Waveform (Option 403)
The signal generator with option 403 can apply additive white gaussian noise (AWGN) to a carrier in real
time while the modulating waveform file is being played by the dual ARB waveform player. The AWGN
can be configured using front panel softkeys. The Carrier to Noise Ratio softkey allows you to specify the
amount of noise power relative to carrier power that is applied to the signal. The Carrier Bandwidth softkey
sets the bandwidth over which the noise is integrated and the Noise Bandwidth Factor softkey allows you to
select a flat noise bandwidth. Refer to the E4428C/38C ESG SCPI Command Reference for remote operation
commands and the E4428C/38C ESG Signal Generator Key and Data Field Reference for key descriptions.
The following procedure sets up a carrier and modulates it using the pre-defined SINE_TEST_WFM
waveform file. AWGN is then applied to the carrier.
Configuring AWGN
1. Preset the signal generator. Press the Preset hardkey.
2. Press the Frequency hardkey and enter 1.5 GHz.
3. Press the Amplitude hardkey and enter –10 dBm.
4. Press RF On Off to On.
5. Press Mode > Dual ARB > Select Waveform and highlight the SINE_TEST_WFM waveform.
6. Press Select Waveform.
7. Press ARB Off On to On.
8. Press ARB Setup > ARB Sample Clock enter 50 MHz.
9. Press Real-time Noise Setup > Carrier to Noise Ratio and enter 30 dB.
10. Press Carrier Bandwidth and enter 40 MHz.
11. Press Real-time Noise Off On to On.
This procedure applies AWGN to the 1.5 GHz carrier. The displayed power level of the signal generator,
–10 dBm, will include the noise power which is set as a carrier to noise ratio (C/N) of 30 dB. Noise power,
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for the purpose of C/N, is applied across a carrier bandwidth of 40 MHz. The default noise bandwidth factor
is 1, which provides a flat noise signal bandwidth of a least 0.8 times the 50 MHz sample rate.
Storing and Loading Waveform Segments
Waveform segments can reside in volatile memory (WFM1), or they can be stored in non-volatile memory
(NVWFM), or both. However, to play or edit a waveform file, the file must reside in WFM1. Because files
stored in volatile memory do not survive a power cycle, it is a good practice to store waveform files to
non-volatile memory and load them to volatile memory whenever you want to use them.
Storing Waveform Segments to Non-Volatile Memory
Recall that there are two types of files used in the dual ARB player, segments (a single waveform file) and
sequences (a series of waveform files). A sequence is comprised of multiple segments and may include other
sequences. Refer to “Creating a Waveform Sequence” on page 109 for more information on segments and
sequences.
The segments that compose a waveform sequence are not stored when the waveform sequence is stored. You
must save any segment or segments used to create a waveform sequence. Storing just the waveform
sequence will result in losing the waveform segments when the signal generator is turned off or rebooted
during an ESG firmware upgrade. When this occurs, you cannot play the waveform sequence until the
segments are recreated using the same file names that the sequence expects. If you attempt to play the
sequence without the segments, an error, ERROR: 629, File format invalid will be reported, since the dual
ARB player can no longer find the waveform segments that make up the sequence.
Waveform segments must reside in volatile memory (WFM1) to be edited or played individually and all
components, such as segments and other sequences, of a sequence must reside in WFM1.
The following example demonstrates storing waveform segments. If you have not created waveform
segments, complete the steps in the previous section, “Creating Waveform Segments” on page 108. In this
example, the sequence is stored to the Catalog of Seq Files and the segments are stored to the
Catalog of NVWFM files.
1. Press Mode > Dual ARB > Waveform Segments.
2. Press Load Store to Store.
3. Highlight the waveform segment you want to store.
4. If the waveform segment needs to be renamed, follow steps a through d, if not, proceed to step five.
a. Press Rename Segment > Editing Keys > Clear Text.
b. Enter a name for the waveform segment using the displayed alpha/symbol softkeys along with the
numeric keypad. The maximum length for a file name is 23 characters (alphanumeric and special
characters).
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Using the Dual ARB Waveform Player
c. Press Enter.
d. Highlight the waveform segment that was renamed.
5. Press Store Segment to NVWFM Memory.
6. Repeat steps three through five for all segments that you want to store.
In addition to the above method for saving segments to NVWFM, the signal generator allows you to store all
files, residing in WFM1, into NVWFM. This is accomplished using the Store All to NVWFM Memory softkey.
Loading Waveform Segments from Non-Volatile Memory
Waveform segments must reside in volatile memory (WFM1) before they can be played, edited, or be
included in a sequence. In addition, you need to load segments into WFM1 whenever power is cycled to the
ESG or an action initiated that causes the ESG to reboot.
1. Press Mode > Dual ARB > Waveform Segments.
2. Highlight the waveform segment you want to load.
3. Press Load Segment From NVWFM Memory.
In addition to the above method, the signal generator allows you to load all files, residing in NVWFM, into
WFM1. This is accomplished using the Load All From NVWFM Memory softkey.
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Understanding the I/Q Modulator Filter
Understanding the I/Q Modulator Filter
The I/Q modulator filter (I/Q Mod Filter Manual Auto softkey) lets you select either post-reconstruction low pass
filtering that has a narrower bandwidth than that of the reconstruction filter, or no post-reconstruction
filtering. It can be used with both real time and ARB signals.
There are two modes for the I/Q modulator filter: auto or manual. With auto, the signal generator
automatically selects either filtering (2.1 MHz or 40 MHz) or no filtering depending on the signal
configuration. With manual, the user can select a 2.1 MHz filter, a 40 MHz filter, or no filter.
The low pass filter selections are fifth order elliptic filters that exhibit very low passband ripple. These filters
are positioned before the I/Q modulator, so the filtering is applied separately to the I and Q paths. Since they
are post-reconstruction filters, they do not apply any oversampling.
Because the filters are for the I and Q signals and not the modulated signal, they are filtering the I/Q
bandwidth, which has up to 40 MHz for I and 40 MHz for Q (80 MHz total I/Q bandwidth). This means that
when viewed through the RF output, the filter size appears to be twice the size of the selected filter. For
example, the 2.1 MHz I/Q bandwidth filter shows as a 4.2 MHz filter in the RF bandwidth.
Through Filter
2.1 MHz Filter
RF Bandwidth
larger than 4 MHz
The 2.1 MHz filter is for improving the ACPR on single carrier wideband signals such as W-CDMA. The
40 MHz filter is best used to eliminate spurious events. As with any filter, the I/Q modulator filters do add
some group delay. To determine whether the filters may be contributing to distortion or some unexpected
signal artifact, select the through path and view the signal. If there is no change in the signal, then the I/Q
modulator filter is not the cause.
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Understanding the I/Q Modulator Filter
Applying An I/Q Modulator Filter
Real Time Signals
1. Configure the signal.
2. Set the I/Q modulator filter:
a. Press I/Q > More (1 of 2) > I/Q Mod Filter Manual Auto.
This key is active only when using a real time signal. When using an ARB signal, the I/Q Mod Filter
Manual Auto softkey within the I/Q menu grays out.
b. In the filter menu, select Through, 2.1 MHz, 40 MHz, or Auto.
3. If not already done, turn on the modulation format.
4. Turn on the RF output.
ARB Signal
The I/Q modulator filter selections reside within the modulation format menu, instead of in the I/Q menu as
for the real time signals. For more information, see “I/Q Attenuator and Filters Settings” on page 117.
1. Configure the signal.
2. Within the ARB modulation format menu, set the I/Q modulator filter:
a. Press ARB Setup > more (1 of 2) > I/Q Mod Filter Manual Auto.
The more (1 of 2) softkey may not appear in all menus.
b. In the filter menu, select Through, 2.1 MHz, 40 MHz, or Auto.
3. If not already done, turn on the modulation format.
4. Turn on the RF output.
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Local Settings for ARB Waveform Formats and the Dual ARB Player
To provide you with the greatest convenience in optimizing and replicating waveforms for playback in the
dual ARB player, settings that were previously (pre-C.03.10 firmware release) found in only the dual ARB
player have now been incorporated into each of the ARB modulation formats. In addition, some of the I/Q
waveform settings previously found in the I/Q and MUX hardkey menus are also present in the ARB
modulation formats and the dual ARB player. These settings are shown in the following list, and explained
in the sections that follow:
•
I/Q output filter
•
I/Q modulator filter
•
I/Q modulator attenuator
•
Waveform runtime scaling
•
High crest mode
•
ARB sample clock
•
Markers
I/Q Attenuator and Filters Settings
The I/Q output filter, modulator attenuator, and the I/Q modulator filter parameters are now set locally
within each ARB modulation format (W-CDMA, CDMA2000, AWGN, Multitone, etc.) and the dual ARB
player. When you set these signal generator parameters within one modulation format, they will not apply to
the others. These settings are applied to the signal generator when the modulation format is turned on or the
saved waveform is selected in the dual ARB player. They can also be saved to the file header. The I/Q output
attenuator (I/Q Output Atten softkey located in the I/Q hardkey menu) still maintains its original behavior in
that it is a global setting (applies to all signal generator formats).
Front Panel Changes
In pre-C.03.10 firmware releases, the I/Q output filter, modulator attenuator, and the I/Q modulator filter
parameters were set globally from the I/Q and/or the Mux hardkey menus using the I/Q Mod Filter Manual
Auto, Modulator Atten nnn dB Manual Auto, I/Q Output Filter Manual Auto, and the I/Q Mod Filter Manual Auto
softkeys. These three softkeys now appear in each of the ARB formats and the dual ARB player. This
enables you to set these parameters locally within each ARB format and the dual ARB player.
The three softkeys in the I/Q and mux menus now apply only to the real time formats and externally applied
I/Q signals. The real time formats are the ones preceded with real time on the ESG softkey labels and usually
have BBG as one of the SCPI command mnemonics. When an ARB format or the dual ARB player is active,
the three softkeys in the I/Q and mux menus are grayed-out indicating that they do not apply to the ARB
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format or the dual ARB player.
Setting the three parameters, for the ARB formats or the dual ARB player, are accomplished by accessing
the ARB Setup softkey menu located in each of the ARB formats and the dual ARB player. The location of
this softkey menu is shown in Figure 4-12.
When you save the signal generator setup using the front panel Save hardkey function with an ARB format
or the dual ARB player, the local settings for the three parameters are also saved.
Figure 4-12
ARB I/Q Filters and Attenuator Softkey Location
First-Level Softkey
Menu
Not all ARB formats will
have a Second Page
*
Only available in the
dual ARB player
* Opt.403 softkey
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SCPI Command Changes
New SCPI commands have been developed and included in the C.03.10 and later versions of the firmware.
These new commands allow you to set the three parameters discussed earlier for each of the ARB
modulation formats and the dual ARB player. Commands have also been changed for the three parameters in
the Digital Modulation subsystem to accommodate the local setting feature.
These new commands duplicate the behavior of the softkeys discussed in the previous section. The main
difference is that now you can set new values for the three parameters (available in the I/Q and/or MUX
menus) while an ARB modulation format is active and playing. However, the new settings will not be
applied until the ARB format is turned off. Then they are used only if a real time modulation format is
turned on or an external I/Q signal is applied to the ESG.
The pre-C.03.10 Digital Modulation subsystem filter and attenuator commands will still work and have the
same behavior, in that they apply changes globally. This means that if you configure a local setting for an
ARB format using the new commands, and then executed the older commands from the Digital Modulation
subsystem, the older commands would override the local settings.
Waveform Runtime Scaling
Waveform runtime scaling enables you to set the scaling value that is applied to the waveform while it is
playing.
You can set waveform runtime scaling in the ARB Setup softkey menu located in the dual ARB player. The
location of this softkey is shown in Figure 4-12. This setting is only available for the dual ARB player.
When you save the signal generator setup using the front panel Save hardkey function with the dual ARB
player, the local setting for waveform runtime scaling is also saved.
High Crest Mode
High crest mode reduces ALC levels while processing ARB waveform files, resulting in signals with less
distortion and improved EVM. However, in the high crest mode, the maximum output level is reduced and
power level accuracy is degraded.
You can set this parameter by in the ARB Setup softkey menu located in the dual ARB player. The location of
this softkey is shown in Figure 4-12. This setting is only available in the dual ARB player.
When you save the signal generator setup using the front panel Save hardkey function with the dual ARB
player, the local setting for high crest mode is also saved.
ARB Sample Clock
Each ARB modulation format and the dual ARB player incorporate a local ARB sample clock parameter.
For example, you can set the ARB CDMA2000 modulation format’s ARB sample rate to 5 MHz, and this
parameter would apply only to the ARB CDMA2000 waveform that is currently playing. The 5 MHz setting
would not be used in any of the other ARB modulation formats or the dual ARB player. If you were to turn
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off the CDMA2000 ARB format and then turn it back on, the factory setting would be applied until you once
again change the ARB sample clock value. This setting can be saved to the file header. In this way you can
set the ARB sample clock while in the ARB modulation format, and have that same setting applied when the
waveform is selected for playback in the dual ARB player.
The accessibility and setting of the ARB sample clock differs between the ARB modulation formats and the
dual ARB player. Within the ARB formats, this parameter can be changed only when the format is active
(on). Any value you enter while the format is active, will be replaced with the factory optimized value when
the format is turned off and then back on. While the ARB format is off, the ARB Sample Clock softkey is
grayed-out. In the dual ARB player, the ARB sample clock setting is accessible even when the dual ARB is
off. You can also set the ARB sample clock when the dual ARB is off and the new setting is applied when
the dual ARB player is turned on. This setting will survive toggling the dual ARB player off and on.
Figure 4-12 on page 118 shows the location for the ARB Sample Clock softkey which is on the first page of the
ARB Setup softkey menu. Even though the figure is for the ARB W-CDMA modulation format, the key path
is the same for all ARB formats and the dual ARB player.
Waveform Markers
Waveform markers are used to mark specific points on a waveform and are available for use in all ARB
modulation formats. The signal generator provides four markers. Each marker can be associated with the RF
blanking function, the ALC hold function, and the alternate amplitude triggering function. A marker can
implement one or all three functions. For more information, refer to the section, “Using Waveform Markers”
on page 124.
NOTE
In the Bluetooth modulation format, markers one and two are automatically set when
payload data types are selected and the waveform is generated. See “Bluetooth Marker
Behavior” on page 123 for more information.
You can set each marker’s polarity and the marker points (first sample point or a range of sample points).
Each marker provides a rear panel output signal using the event connector (EVENT 1, 2, 3, or 4) that
corresponds to the marker number. The EVENT 3 and 4 connectors are actually pins located on the AUX
I/O connector. For more information on the AUX I/O connector, see“Rear Panel Overview” on page 37.
The ALC hold marker function holds the ALC modulator at its current level when the marker signal is low.
When the marker signal goes high, the ALC hold function is discontinued.
ALC hold is automatically incorporated in the RF blanking marker function. So if you select the RF
blanking marker function (Pulse/RF Blank softkey), there is no need to select the ALC hold marker function
for the same marker number. You can use the ALC hold function by itself when you have a waveform signal
that incorporates idle periods or when the increased dynamic range encountered with RF blanking is not
desired. The ALC hold should only be used for short periods of time of less than 100 ms. Extended periods
of using the ALC hold feature may affect the waveform’s output amplitude.
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The alternate amplitude marker function triggers the Alternate Amplitude feature located in the Amplitude
hardkey menu. You still need to set up the alternate amplitude parameters. The trigger selection for the
alternate amplitude feature in the Amplitude hardkey menu should be set to internal.When the marker signal
goes low, the alternate amplitude function is triggered. When the marker signal goes high, the trigger is
terminated disengaging alternate amplitude.
Marker settings are located in the Marker Utilities softkey menu. The location of this softkey and the marker
softkey menus are shown in Figure 4-13. Even though the figure is for the ARB W-CDMA modulation
format, the key path is the same for all ARB formats and the dual ARB player.
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Figure 4-13
ARB Marker Location and Softkey Menus
First-Level Softkey
Menu
Not all ARB formats will
have a Second Page
*
* Opt. 403 softkey
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Local Settings for ARB Waveform Formats and the Dual ARB Player
Bluetooth Marker Behavior
Bluetooth markers one and two have predetermined settings that are implemented when a payload data type
is selected and the waveform is generated. A waveform is regenerated when a new payload data type is
selected while the modulation format is on. These predetermined settings will override the current marker
settings if they are different. However they do not affect the ALC hold and the alternate amplitude marker
functions. But they will affect the RF blanking function. After the waveform has been
generated/regenerated, you can modify the predetermined settings to suit your measurement needs. The
following list explains the predetermined settings for marker one and two according to the selected payload
data type:
Truncated PN9 or 8-bit
pattern
Marker one outputs a five-sample-point wide pulse (500 ns) at the EVENT
1 rear panel connector, and marker two implements RF blanking during
the time that the Bluetooth signal is low.
Continuous PN9
Marker one outputs a 1 MHz clock signal at the EVENT 1 rear panel
connector, and marker two outputs a 216 µs gated pulse signal at the
EVENT 2 rear panel connector that aligns with the transmission of the
payload data.
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Using Waveform Markers
The signal generator provides four waveform markers to mark specific points on a waveform segment.
When the signal generator encounters an enabled marker, an auxiliary output signal is routed to the rear
panel event connector (described in the “Rear Panel Overview” on page 37) that corresponds to the marker
number. You can use this auxiliary output signal to synchronize another instrument with the waveform, or as
a trigger signal to start a measurement at a given point on a waveform.
You can also configure markers to initiate ALC hold, or RF Blanking (which includes ALC hold). Refer to
“Waveform Markers” on page 120 for more information.
Creating a waveform segment (page 108) also creates a marker file that places a marker point on the first
sample point of the segment for markers one and two. When a waveform file is downloaded that does not
have a marker file associated with it, the signal generator creates a marker file without any marker points.
Factory-supplied segments have a marker point on the first sample for all four markers.
The following procedures demonstrate how to use markers while working in the dual ARB player, but the
process is the same when working in any ARB format.
These procedures also discuss two types of points: a marker point and a sample point. A marker point is a
point at which a given marker is set on a waveform; you can set one or more marker points for each marker.
A sample point is one of the many points that compose a waveform.
There are three basic steps to using waveform markers:
“Clearing Marker Points from a Waveform Segment” on page 131
“Setting Marker Points in a Waveform Segment” on page 132
“Controlling Markers in a Waveform Sequence (Dual ARB Only)” on page 134
This section also provides the following information:
•
“Waveform Marker Concepts” on page 125
•
“Accessing Marker Utilities” on page 129
•
“Viewing Waveform Segment Markers” on page 130
•
“Viewing a Marker Pulse” on page 136
•
“Using the RF Blanking Marker Function” on page 137
•
“Setting Marker Polarity” on page 139
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Using Waveform Markers
Waveform Marker Concepts
The signal generator’s ARB formats provide four waveform markers to mark specific points on a waveform
segment. You can set each marker’s polarity and marker points (on a single sample point or over a range of
sample points). Each marker can also perform ALC hold or RF Blanking and ALC hold.
Positive
Marker
File
Bit N
EVENT N
Marker N
RF Blank Off On
Set Marker
On Off
Marker
Polarity
Marker N
Blanks RF
when Marker
is Low
Negative
When the signal generator encounters an enabled marker (described on
page 134), an auxiliary output signal is generated and routed to the rear
panel event connector that corresponds to the marker number (N).
The EVENT 3 and 4 connectors are pins on the AUXILIARY I/O connector
(connector locations are shown in Figure on page 41).
RF Blank Only: includes ALC Hold
Marker N
Holds ALC
when Marker
is Low
Marker N
ALC Hold Off On
Marker File Generation
Generating a waveform segment (see page 108) automatically creates a marker file that places a marker
point on the first sample point of the segment for markers one and two.
Downloading a waveform file (as described in the E4428C/38C ESG Signal Generators Programming
Guide) that does not have a marker file associated with it causes the signal generator to automatically create
a marker file but does not place any marker points.
Marker Point Edit Requirements
Before you can modify a waveform segment’s marker points, the segment must reside in volatile memory
(WFM1). Refer to the section, “Loading Waveform Segments from Non-Volatile Memory” on page 114 for
more information.
In the dual ARB player, you can modify a waveform segment’s marker points either without playing the
waveform, or while playing the waveform in an ARB modulation format. In an ARB modulation format,
you must play the waveform before you can modify a segment’s marker points.
Saving Marker Polarity and Routing Settings
Marker polarity and routing settings remain until you reconfigure them, preset the signal generator, or cycle
the ESG power. To ensure that a waveform uses the correct settings when it is played, set the marker
polarities or routing (RF Blanking and ALC Hold), and save the information to the file header (page 93).
This is especially important when the segment plays as part of a sequence because the previously played
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Using Waveform Markers
segment could have different marker and routing settings.
ALC Hold Marker Function
While you can set a marker function (described as Marker Routing on the softkey label) either before or after
you set marker points (page 132), setting a marker function before setting marker points may cause power
spikes or loss of power at the RF output.
Use the ALC hold function by itself when you have a waveform signal that incorporates idle periods, or
when the increased dynamic range encountered with RF blanking (page 137) is not desired.
The ALC hold marker function holds the ALC circuitry at the average (RMS) value of the sampled points
set by the marker(s). For both positive and negative marker polarity, the ALC samples the RF output signal
(the carrier plus any modulating signal) when the marker signal goes high:
Positive:
Negative
The signal is sampled during the on marker points.
The signal is sampled during the off marker points.
The marker signal has a minimum of a two sample point delay in its response relative to the waveform signal
response. To compensate for the marker signal delay, offset marker points from the waveform sample at
which you want the ALC sampling to begin.
NOTE
Because it can affect the waveform’s output amplitude, do not use the ALC hold for longer than
100 ms. For longer time intervals, refer to “Power Search Mode” on page 659.
Positive Polarity
CAUTION
126
Incorrect ALC sampling can create a sudden unleveled condition that may create a spike in
the RF output, potentially damaging a DUT or connected instrument. To prevent this
condition, ensure that you set markers to let the ALC sample over an amplitude that
accounts for the higher power levels encountered within the signal.
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Using Waveform Markers
Example of Correct Use
Waveform: 1022 points
Marker range: 95-97
Marker polarity: Positive
This example shows a marker set to sample the waveform’s area of
highest amplitude. Note that the marker is set well before the
waveform’s area of lowest amplitude. This takes into account the
response difference between the marker and the waveform signal.
Close-up of averaging
The ALC samples the waveform when the marker signal goes
high, and uses the average of the sampled waveform to set the
ALC circuitry.
Here the ALC samples during the on marker points (positive
polarity).
Marker
Marker
Example of Incorrect Use
Waveform: 1022 points
Marker range: 110-1022
Marker polarity: Positive
Marker
Marker
This example shows a marker set to sample the low part of the
same waveform, which sets the ALC modulator circuitry for
that level; this usually results in an unleveled condition for the
signal generator when it encounters the high amplitude of the
pulse.
Chapter 4
Marker
Marker
Pulse Unleveled
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Using Waveform Markers
Example of Incorrect Use
Waveform: 1022 points
Marker range: 110-1022
Marker polarity: Negative
This figure shows that a negative polarity marker goes low during
the marker on points; the marker signal goes high during the off
points. The ALC samples the waveform during the off marker
points.
Marker On
Marker
Off
Marker On
Sample range begins on first point of signal
Sampling both on and off time sets the modulator circuitry
incorrectly for higher signal levels. Note the increased amplitude
at the beginning of the pulse.
Marker On
Marker
Off
Marker
On
Negative range set between signal and
off time
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Accessing Marker Utilities
Use the following procedure to display the marker parameters. This procedure uses the dual ARB player, but
you can access the marker utilities through the ARB Setup softkey in all ARB formats.
1. Select the ARB waveform player:
press Mode > Dual ARB
2. Press ARB Setup > Marker Utilities.
When using an ARB format other than
dual ARB, you must turn on the format
to enable the Set Markers softkey.
NOTE
Chapter 4
Most of the procedures in this section begin at the Marker Utilities softkey menu.
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Using Waveform Markers
Viewing Waveform Segment Markers
Markers are applied to waveform segments. Use the following steps to view the markers set for a segment
(this example uses the factory-supplied segment, SINE_TEST_WFM).
1. In the Marker Utilities menu (page 129), press Set Markers.
2. Highlight the desired waveform segment. In an ARB format such as Custom Arb Waveform Generator,
there is only one file (AUTOGEN_WAVEFORM) and it is highlighted.
3. Press Display Markers > Zoom in Max. The maximum zoom in range is 28 points.
Experiment with the Zoom functions to see how they display the markers.
The display can show a maximum of 460 points; displayed waveforms with a sample point range greater
than 460 points may not show the marker locations.
Select a segment
The Set Marker display
The display below shows the I and Q components of the waveform, and
the marker points set in a factory-supplied segment.
First sample
point shown on
display
These softkeys
change the range
of waveform
sample points
shown on the
marker display.
Marker
points on
first sample
point
130
Each press of the
softkey changes
the sample range
by approximately
a factor of two
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Using Waveform Markers
Clearing Marker Points from a Waveform Segment
When you set marker points they do not replace points that already exist, but are set in addition to existing
points. Because markers are cumulative, before you set points, view the segment (page 130) and remove
any unwanted points. With all markers cleared, the level of the event output signal is 0V.
Clearing All Marker Points
1. In the Marker Utilities menu (page 129), press Set Markers.
2. Highlight the desired waveform segment.
In an ARB format, there is only one file (AUTOGEN_WAVEFORM) and it is already highlighted.
3. Highlight the desired marker number:
Press Marker 1 2 3 4.
4. For the selected marker number, remove all marker points in the selected segment:
Press Set Marker Off All Points.
5. Repeat from Step 3 for any remaining marker points that you want to remove.
Clearing a Range of Marker Points
The following example uses a waveform with marker points (Marker 1) set across points 10−20. This makes
it easy to see the affected marker points. The same process applies whether the existing points are set over a
range or as individual points (page 125).
1. In the Marker Utilities menu (page 129), select the desired marker (for this example, Marker 1).
2. Set the first sample point that you want off (for this example, 13):
Press Set Marker Off Range Of Points > First Mkr Point > 13 > Enter.
3. Set the last marker point in the range that you want off to a value less than or equal to the number of
points in the waveform, and greater than or equal to the value set in Step 2 (for this example, 17):
Press Last Mkr Point > 17 > Enter > Apply To Waveform > Return.
This turns off all marker points for the active marker within the range set in Steps 2 and 3, as shown in
the following figure.
Viewing markers is described on page 130
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Using Waveform Markers
Clearing a Single Marker Point
Use the steps described in “Clearing a Range of Marker Points” on page 131, but set both the first and last
marker point to the value of the point you want to clear. For example, if you want to clear a marker on point
5, set both the first and last value to 5.
Setting Marker Points in a Waveform Segment
To set marker points on a segment, the segment must reside in volatile memory (page 114).
When you set marker points, they do not replace points that already exist, but are set in addition to existing
points. Because markers are cumulative, before you set marker points within a segment, view the segment
(page 130) and remove any unwanted points (page 125).
Placing a Marker Across a Range of Points
1. In the Marker Utilities menu (page 129), press Set Markers.
2. Highlight the desired waveform segment.
In an ARB format, there is only one file (AUTOGEN_WAVEFORM) and it is already highlighted.
3. Highlight the desired marker number:
Press Marker 1 2 3 4
4. Set the first sample point in the range (in this example, 10):
Press Set Marker On Range Of Points > First Mkr Point > 10 > Enter.
5. Set the last marker point in the range to a value less than or equal to the number of points in the
waveform, and greater than or equal to the first marker point (in this example, 20):
Press Last Mkr Point > 20 > Enter.
6. Press Apply To Waveform > Return.
This sets a range of waveform marker points. The marker signal starts on sample point 10, and ends on
sample point 20, as shown in the following figure.
Viewing markers is described on page 130
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Using Waveform Markers
Placing a Marker on a Single Point
On the First Point
1. In the Marker Utilities menu (page 129), press Set Markers.
2. Highlight the desired waveform segment.
In an ARB format, there is only one file (AUTOGEN_WAVEFORM) and it is already highlighted.
3. Highlight the desired marker number:
Press Marker 1 2 3 4.
4. Press Set Marker On First Point.
This sets a marker on the first point in the segment for the marker number selected in Step 3.
On Any Point
Use the steps described in “Setting Marker Points in a Waveform Segment” on page 132, but set both the
first and last marker point to the value of the point you want to set. For example, if you want to set a marker
on point 5, set both the first and last value to 5.
Placing Repetitively Spaced Markers
The following example sets markers across a range of points and specifies the spacing (skipped points)
between each marker. You must set the spacing before you apply the marker settings; you cannot apply
skipped points to a previously set range of points.
1. Remove any existing marker points (page 125).
2. In the Marker Utilities menu (page 129), press Set Markers.
3. Highlight the desired waveform segment.
In ARB formats there is only one file (AUTOGEN_WAVEFORM) and it is already highlighted.
4. Highlight the desired marker number: Press Marker 1 2 3 4.
5. Set the first sample point in the range (in this example, 5):
Press Set Marker On Range Of Points > First Mkr Point > 5 > Enter.
6. Set the last marker point in the range to a value less than the number of points in the waveform, and
greater than or equal to the first marker point (in this example, 25):
Press Last Mkr Point > 25 > Enter.
7. Enter the number of sample points that you want skipped (in this example, 1):
Press # Skipped Points > 1 > Enter.
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8. Press Apply To Waveform > Return.
This causes the marker to occur on every other point (one sample point is skipped) within the marker point
range, as shown below.
Viewing markers is described on page 130
One application of the skipped point feature is the creation of a clock signal as the auxiliary output.
Controlling Markers in a Waveform Sequence (Dual ARB Only)
In a waveform segment, an enabled marker point generates an auxiliary output signal that is routed to the
rear-panel event connector (described in “Rear Panel Overview” on page 37) corresponding to that marker
number. For a waveform sequence, you enable or disable markers on a segment-by-segment basis; this
enables you to output markers for some segments in a sequence, but not for others. Unless you change the
marker settings or cycle the power, the setting remains the same for the next loaded sequence.
As You Create a Waveform Sequence
After you select the waveform segments to create a waveform sequence, and before you name and save the
sequence, you can enable or disable each segment’s markers independently. Enabling a marker that has no
marker points (page 132) has no effect on the auxiliary outputs.
1. Select the waveform segments (Step 1 on page 109).
2. Toggle the markers as desired:
a. Highlight the first waveform segment.
b. Press Enable/Disable Markers.
c. As desired, press Toggle Marker 1, Toggle Marker 2, Toggle Marker 3, and Toggle Marker 4.
Toggling a marker that has no marker points (page 132) has no effect on the auxiliary outputs.
An entry in the Mkr column (see figure below) indicates that the marker is enabled for that segment;
no entry in the column means that all markers are disabled for that segment.
d. In turn, highlight each of the remaining segments and repeat Step c.
3. Press Return.
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4. Name and store the waveform sequence “Storing Waveform Segments to Non-Volatile Memory” on
page 113.
The following figure shows a sequence built reusing the same factory-supplied waveform segment; a
factory-supplied segment has a marker point on the first sample for all four markers. In this example,
Marker 1 is enabled for the first segment, Marker 2 is enable for the second segment, and markers 3 and 4
are enabled for the third segment.
Sequence Marker Column
This entry shows that
markers 3 and 4 are enabled
for this segment.
For each segment, only the markers enabled for that segment produce a rear-panel auxiliary output signal. In
this example, the Marker 1 auxiliary signal appears only for the first segment, because it is disabled for the
remaining segments. The Marker 2 auxiliary signal appears only for the second segment, and the marker 3
and 4 auxiliary signals appear only for the third segment.
In an Existing Waveform Sequence
If you have not already done so, create and store a waveform sequence that contains at least three segments
(page 109). Ensure that the segment or segments are available in volatile memory (page 114).
1. Press Mode > Dual ARB > Waveform Sequences, and highlight the desired waveform sequence.
2. Press Edit Selected Waveform Sequence, and highlight the first waveform segment.
3. Press Enable/Disable Markers > Toggle Marker 1, Toggle Marker 2, Toggle Marker 3, and Toggle Marker 4.
Toggling a marker that has no marker points (page 132) has no effect on the auxiliary outputs.
An entry in the Mkr column indicates that the marker is enabled for that segment; no entry in the column
means that all markers are disabled for that segment
4. Highlight the next waveform segment and toggle the desired markers (in this example, markers 1 and 4).
5. Repeat Step 4 as desired (for this example, select the third segment and toggle marker 3).
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6. Press Return > Name And Store > Enter.
The markers are enabled or disabled per your selections, and the changes have been saved to the selected
sequence file.
Sequence Marker Column
This entry shows that only
marker 3 is enabled for this
segment.
Viewing a Marker Pulse
When a waveform plays (page 110), you can detect a set and enabled marker’s pulse at the rear panel event
connector that corresponds to that marker number. This example demonstrates how to view a marker pulse
generated by a waveform segment that has at least one marker point set (page 132). The process is the same
for a waveform sequence.
This procedure uses the factory-supplied segment, SINE_TEST_WFM in the dual ARB Player.
Factory-supplied segments have a marker point on the first sample point for all four markers, as shown.
Marker points on
first sample point of
waveform segment
Viewing markers is described on page 130
1. Press Mode > Dual ARB > Select Waveform, and highlight the SINE_TEST_WFM segment.
2. Press ARB Off On to On.
3. Connect the ESG’s rear-panel Q OUT output to the oscilloscope’s channel 1 input.
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4. Connect the ESG’s rear-panel EVENT 1 output to the oscilloscope’s channel 2 input. When marker 1 is
present, the ESG outputs a signal on the EVENT 1 connector as shown in the following example.
RF Output
Marker pulse on the Event 1 signal.
Using the RF Blanking Marker Function
While you can set a marker function (described as Marker Routing on the softkey label) either before or after
setting the marker points (page 132), setting a marker function before you set marker points may change the
RF output. RF Blanking includes ALC hold (described on page 126, note Caution regarding unleveled
power). The signal generator blanks the RF output when the marker signal goes low.
1. Using the factory-supplied segment SINE_TEST_WFM, set Marker 1 across points 1−180 (page 132).
2. From the Marker Utilities menu (page 129), assign RF Blanking to Marker 1:
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Press Marker Routing > Pulse/RF Blank > Marker 1.
Marker Polarity = Positive
RF Signal
When marker polarity is positive (the
default setting), the RF output is blanked
during the off maker points.
≈3.3V
0V
Marker
Point 1
Segment
180
200
Marker Polarity = Negative
RF Signal
When marker polarity is negative, the
RF output is blanked during the on
maker points
≈3.3V
0V
Marker
Point 1
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Segment
180
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Setting Marker Polarity
Setting a negative marker polarity inverts the marker signal.
1. In the Marker Utilities menu (page 129), press Marker Polarity.
2. Select the marker polarity as desired for each marker number.
Default Marker Polarity = Positive
Set each marker polarity independently.
See Also: “Saving Marker Polarity and Routing Settings” on page 125.
As shown on page 137:
Positive Polarity:
On marker points are high (≈3.3V).
Negative Polarity: On marker points are low (0V).
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Triggering Waveforms
Triggering Waveforms
Triggering is available in both ARB and real time formats. ARB triggering controls the playback of a
waveform file; real time custom triggering controls the transmission of a data pattern. The examples and
discussions in this section use the dual ARB Player, but the functionality and methods of access (described
on page 142) are similar in all ARB and real time formats.
Triggers control data transmission by telling the ESG when to transmit the modulating signal. Depending on
the trigger settings, the data transmission may occur once, continuously, or the ESG may start and stop the
transmission repeatedly (Gated mode).
A trigger signal comprises both positive and negative signal transitions (states), which are also called high
and low periods; you can configure the ESG to trigger on either state. It is common to have multiple triggers,
also referred to as trigger occurrences or trigger events, occur when the signal generator requires only a
single trigger. In this situation, the ESG recognizes the first trigger event and ignores the rest.
When you select a trigger mode, you may lose the signal (carrier plus modulation) from the RF output until
you trigger the modulating signal. This is because the ESG sets the I and Q signals to zero volts prior to the
first trigger event, which suppresses the carrier. If you create a data pattern with the initial I and Q voltages
set to values other than zero, this does not occur. After the first trigger event, the signal’s final I and Q levels
determine whether you see the carrier signal or not (zero = no carrier, other values = visible carrier). At the
end of most data patterns, the final I and Q points are set to a value other than zero.
There are four parts to configuring a waveform trigger:
•
•
•
•
140
Source determines how the ESG receives the trigger that initiates waveform play.
Mode determines the waveform’s overall behavior when it plays.
Response determines the specifics of how the waveform responds to a trigger.
Polarity determines the state of the trigger to which the waveform responds (used only with an external
trigger source); you can set either negative, or positive.
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Source
The figure below shows the dual ARB mode trigger menu.
The Trigger hardkey
A command sent through the rear-panel GPIB, LAN, or Auxiliary (RS-232) interface
An external trigger signal applied to either the PATTERN TRIG IN connector, or the PATT TRIG IN
pin on the AUXILIARY I/O connector (connector locations are shown in Figure on page 41).
The following parameters affect an external trigger signal:
• The source (Input connector) of the external trigger signal (see page 142)
• The polarity of the external trigger (described on page 143)
• Any desired delay between when the ESG receives an external trigger and when the
waveform responds to it (see page 142).
Mode and Response
The arbitrary waveform player provides four trigger modes; each mode has one or more possible responses:
•
Single plays the waveform once. Arb formats have the following re-triggering options:
— Off ignores triggers received during play; a trigger received after playback completes restarts the
playback.
— On causes a trigger received during play to repeat the waveform after the current play completes.
— Immediate causes a trigger received during play to immediately restart the waveform.
•
Gated causes the waveform to wait for the first active trigger signal state to begin transmission, then
repeatedly starts and stops in response to an externally applied gating signal (example on page 143).
You select the active state with the Gate Active Low High softkey (see page 143).
In an ARB format, the waveform plays during the inactive state, and stops during the active state.
In real time Custom, behavior depends on whether the signal uses framed or unframed data.
Because the ESG provides only unframed data, to transmit a framed data signal you must create an
external file that incorporates the framing and download it to the ESG (see the E4428C/38C ESG Signal
Generators Programming Guide).
— Unframed data transmits during active states, and stops during inactive states. The signal stops at the
last transmitted symbol and restarts at the next symbol.
— Framed data starts transmitting at the beginning of a frame during active states, and stops at the end
of a frame when the end occurs during inactive states. If the end of the frame extends into the next
active state, the signal transmits continuously.
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•
Segment Advance (dual ARB only) causes a segment in a sequence to require a trigger to play. The trigger
source controls how play moves from segment to segment (example on page 145). A trigger received
during the last segment loops play to the first segment in the sequence. You have two choices as to how
the segments play:
— Single causes a segment in a sequence to play once, after which the dual ARB player stops and waits
for a trigger before advancing to the next segment, and playing that segment to completion. Triggers
received during play cause the current segment to finish, the dual ARB player advances to the next
segment, and plays that segment to completion.
— Continuous causes a segment in a sequence to play continuously until the waveform receives another
trigger. Triggers received during play cause the current segment to finish, then play advances to the
next segment, which plays continuously.
•
Continuous repeats the waveform until you turn the signal off or select another waveform, trigger mode,
or response. Continuous has the following functions:
— Free Run immediately triggers and plays the waveform; triggers received during play are ignored.
— Trigger & Run plays the waveform when a trigger is received; subsequent triggers are ignored.
— Reset & Run (not available in real time Custom) plays the waveform when a trigger is received;
subsequent triggers restart the waveform.
Accessing Trigger Utilities
The following figures show the menus for the trigger parameters. These figures show the dual ARB player,
but you can access the trigger utilities through the Trigger softkey in all ARB formats, and the Pattern Trigger
softkey in the Real Time I/Q Baseband (Custom) format.
PATTERN TRIG IN connector
PAT TRIG IN 2 pin on
the AUXILARY I/O connector
Active only when
Ext is selected.
Ext Delay Off On for all
other Arb formats.
•
142
To display the trigger modes, press Mode > Dual ARB > Trigger.
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•
To display the response selections available for a given trigger mode, press Trigger Setup, then select the
desired trigger mode. To see the selections for Single mode in an ARB format, select Retrigger Mode; in
real time Custom, selecting Single mode causes the data pattern to play once when triggered.
•
To display the trigger source options, press Trigger Setup > Trigger Source.
Setting the Polarity of an External Trigger
Gated Mode
The selections available with the gate active parameter refer to the low and high states of an external trigger
signal. For example, when you select High, the active state occurs during the high of the trigger signal.
ARB Formats
When the active state occurs, the ESG stops the waveform file playback at the last
played sample point, and restarts the playback at the next sample point when the
inactive state occurs.
Real Time Custom When the active state occurs, the ESG transmits the data pattern. When the inactive
state occurs, the transmission stops at the last transmitted symbol, and restarts at the
next symbol when the active state occurs.
Continuous, Single, or Segment Advance Modes
The Ext Polarity Neg Pos softkey selections refer to the low (negative) and high (positive) states of an external
trigger. With Neg selected (the default), the ESG responds during the low state of the trigger signal.
Using Gated Triggering
Gated triggering enables you to define the on (playback) and off states of a modulating waveform. This
example uses the factory supplied segment, SINE_TEST_WFM.
1. Connect the output of a function generator to the signal generator’s rear-panel PATTERN TRIG IN, as
shown in the following figure.
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This connection is applicable to all external triggering methods. The optional oscilloscope connection
enables you to see the effect that the trigger signal has on the RF output.
2. Preset the signal generator.
3. Configure the carrier signal output:
•
•
•
Set the desired frequency.
Set the desired amplitude.
Turn on the RF output.
4. Select a waveform for playback (sequence or segment):
a. Preset the signal generator.
b. Press Mode > Dual ARB > Select Waveform.
c. Highlight a waveform file (for this example, SINE_TEST_WFM).
d. Press Select Waveform.
5. Select the waveform trigger method:
a. Press Trigger > Gated.
b. Press Trigger > Trigger Setup and note that for the Gate Active Low High softkey, the default selection is
High, which is the selection used in this example.
6. Select the trigger source and rear panel input:
a. For the Trigger Source softkey, the default selection is Ext, which is the selection used in this example
(gated triggering requires an external trigger).
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b. Press Trigger Source and note that for the Ext Source softkey, the default selection is Patt Trig In 1, which
is the selection used in this example.
7. Generate the waveform:
Press ARB Off On to On.
8. On the function generator, configure a TTL signal for the external gating trigger.
9. (Optional) Monitor the current waveform:
Configure the oscilloscope to display both the output of the signal generator, and the external triggering
signal. You will see the waveform modulating the output during the gate inactive periods (low).
The following figure shows an example display.
Modulating Waveform
RF Output
Externally Applied Gating Signal
Gate Active = High
NOTE
In the real time Custom mode, the behavior is reversed: when the gating signal is high, you
see the modulated waveform.
Using Segment Advance Triggering
Segment advance triggering enables you to control the segment playback within a waveform sequence. The
following example uses a waveform sequence that has two segments.
If you have not created and stored a waveform sequence, complete the steps in the sections, “Creating
Waveform Segments” on page 108, and “Creating a Waveform Sequence” on page 109.
1. Preset the signal generator.
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2. Configure the RF output:
•
•
•
Set the desired frequency.
Set the desired amplitude.
Turn on the RF output.
3. Select a waveform sequence for playback:
a. Press Mode > Dual ARB > Select Waveform.
b. Highlight a waveform sequence file.
c. Press Select Waveform.
4. Select the waveform trigger method and trigger source:
a. Press Trigger > Segment Advance.
b. Press Trigger > Trigger Setup and note that the Seg Advance Mode softkey displays the default selection
(Continuous), which is the selection used in this example.
c. Press Trigger Source > Trigger Key.
5. Generate the waveform sequence:
Press Return > Return > ARB Off On to On.
6. Trigger the first waveform segment to begin playing repeatedly:
Press the Trigger hardkey.
7. (Optional) Monitor the current waveform:
Connect the output of the signal generator to the input of an oscilloscope, and configure the oscilloscope
so that you can see the output of the signal generator.
8. Trigger the second segment:
Press the Trigger hardkey.
The second segment in the sequence now plays. Pressing the Trigger hardkey causes the current playback
to finish and the next segment to start; when the last segment plays, pressing the Trigger hardkey causes
the first segment in the waveform sequence to start when the current segment finishes.
Using External Triggering
Using this procedure, you learn how to utilize an external function generator to apply a delayed
single-trigger to a custom multicarrier CDMA waveform.
Required Equipment
Agilent 33120A Function Generator
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Connecting the Equipment
Connect the signal generator to the function generator, as shown in Figure 4-14.
Figure 4-14
Configuring a Custom Multicarrier CDMA State
1. Press Preset.
2. Press Mode > CDMA > Arb IS-95A.
3. Toggle Multicarrier Off On to On.
4. Press Setup Select > 4 Carriers.
Configuring the Waveform Trigger
1. Press Trigger > Single.
2. Press Trigger > Trigger Setup >Trigger Source > Ext.
3. Press Ext Polarity Neg Pos until Pos is highlighted.
4. Press Ext Delay Off On to On.
5. Press Ext Delay Time > 100 > msec.
The waveform will now trigger once 100 milliseconds after it detects a change in TTL state from low to high
at the PATT TRIG IN rear panel connector.
Configuring the Function Generator
Set the function generator waveform to a 0.1 Hz square wave at an output level of 0 to 5V.
Generating the Waveform
Press Mode > CDMA > Arb IS-95A > CDMA Off On to On.
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This generates a waveform with the custom multicarrier CDMA state configured in the previous section.
The display changes to Multicarrier Setup: 4 CARRIERS. During waveform generation, the CDMA
and I/Q annunciators activate and the new custom multicarrier CDMA state is stored in volatile ARB
memory. The waveform is now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 890.01 MHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off to On.
The externally single-triggered custom multicarrier CDMA waveform is now available at the signal
generator’s RF OUTPUT connector 100 msec after receiving a change in TTL state from low to high at the
PATT TRIG IN, provided by the function generator output.
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Using Waveform Clipping
Using Waveform Clipping
Waveforms with high power peaks can cause intermodulation distortion, which generates spectral regrowth
(a condition that interferes with signals in adjacent frequency bands). The clipping function enables you to
reduce high power peaks by clipping the I and Q data to a selected percentage of its highest peak.
The clipping feature is available only with the dual ARB mode.
How Power Peaks Develop
To understand how clipping reduces high power peaks, it is important to know how the peaks develop as the
signal is constructed.
I/Q waveforms can be the summation of multiple channels (see Figure 4-15). Whenever most or all of the
individual channel waveforms simultaneously contain a bit in the same state (high or low), an unusually
high power peak (negative or positive) occurs in the summed waveform. This does not happen frequently
because the high and low states of the bits on these channel waveforms are random, which causes a
cancelling effect.
Figure 4-15
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The I and Q waveforms combine in the I/Q modulator to create an RF waveform. The magnitude of the RF
envelope is determined by the equation
value.
, where the squaring of I and Q always results in a positive
As shown in Figure 4-16, simultaneous positive and negative peaks in the I and Q waveforms do not cancel
each other, but combine to create an even greater peak.
Figure 4-16
150
Combining the I and Q Waveforms
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How Peaks Cause Spectral Regrowth
Because of the relative infrequency of high power peaks, a waveform will have a high peak-to-average
power ratio (see Figure 4-17). Because a transmitter’s power amplifier gain is set to provide a specific
average power, high peaks can cause the power amplifier to move toward saturation. This causes
intermodulation distortion, which generates spectral regrowth.
Figure 4-17
Peak-to-Average Power
Spectral regrowth is a range of frequencies that develops on each side of the carrier (similar to sidebands)
and extends into the adjacent frequency bands (see Figure 4-18). Consequently, spectral regrowth interferes
with communication in the adjacent bands. Clipping can provide a solution to this problem.
Figure 4-18
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Using Waveform Clipping
How Clipping Reduces Peak-to-Average Power
You can reduce peak-to-average power, and consequently spectral regrowth, by clipping the waveform.
Clipping limits power peaks in waveforms by clipping the I and Q data to a selected percentage of its highest
peak. The ESG Vector Signal Generator provides two different methods of clipping: circular and
rectangular. Circular clipping is defined as clipping the composite I/Q data (I and Q data are equally
clipped). Rectangular clipping is defined as independently clipping the I and Q data.
During circular clipping, clipping is applied to the combined I and Q waveform (|I + jQ|). Notice in Figure
4-19 that the clipping level is constant for all phases of the vector representation and appears as a circle.
During rectangular clipping, clipping is applied to the I and Q waveforms separately (|I|, |Q|). Notice in
Figure 4-20 on page 153 that the clipping level is different for I and Q; therefore, it appears as a rectangle in
the vector representation. With either method, the objective is to clip the waveform to a level that effectively
reduces spectral regrowth, but does not compromise the integrity of the signal. Figure 4-21 on page 154 uses
two complementary cumulative distribution plots to show the reduction in peak-to-average power that
occurs after applying circular clipping to a waveform.
The lower you set the clipping value, the lower the peak power that is passed (or the more the signal is
clipped). Often, the peaks can be clipped successfully without substantially interfering with the rest of the
waveform. Data that might be lost in the clipping process is salvaged because of the error correction inherent
in the coded systems. If you clip too much of the waveform, however, lost data is irrecoverable. You may
have to try several clipping settings to find a percentage that works well.
Figure 4-19
152
Circular Clipping
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Figure 4-20
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Rectangular Clipping
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Using Waveform Clipping
Figure 4-21
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Reduction of Peak-to-Average Power
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Using Waveform Clipping
Configuring Circular Clipping
This procedure shows you how to configure circular clipping. The circular setting clips the composite I/Q
data (I and Q data are clipped equally). For more information about circular clipping, refer to “How Clipping
Reduces Peak-to-Average Power” on page 152.
1. Press Preset > Mode > Custom > Arb Waveform Generator > Digital Modulation Off On to On. This generates a
custom arbitrary waveform for use in this procedure. You can also use a previously stored or
downloaded waveform.
2. Press Mode > Dual ARB > Select Waveform and ensure that AUTOGEN_WAVEFORM is highlighted on the
display. AUTOGEN_WAVEFORM is the default name assigned to the waveform you generated in the
previous step.
3. Press Select Waveform. This selects the waveform and returns you to the previous softkey menu.
4. Press ARB Off On to On. The dual Arb player must be turned on to display the CCDF plot in the following
steps.
5. Press ARB Setup > Waveform Utilities > Waveform Statistics and ensure that AUTOGEN_WAVEFORM is
highlighted on the display.
6. Press CCDF Plot and observe the position of the waveform’s curve, which is the darkest line.
7. Press Return > Return > Clipping.
8. Ensure that the Clipping Type |I+jQ| |I|,|Q| softkey is set to |I+jQ|, which is circular clipping.
9. Press Clip |I+jQ| To > 80 > % > Apply to Waveform. The I and Q data are both clipped by 80%. Once
clipping is applied to the waveform it cannot be undone. Repeated use of the clipping function has a
cumulative effect on the waveform.
10. Press Waveform Statistics > CCDF Plot and observe the waveform’s curve. Notice the reduction in
peak-to-average power, relative to the previous plot, after applying clipping.
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Configuring Rectangular Clipping
This procedure shows you how to configure rectangular clipping. The rectangular setting clips the I and Q
data independently. For more information about rectangular clipping, refer to “How Clipping Reduces
Peak-to-Average Power” on page 152.
1. Press Preset > Mode > Custom > Arb Waveform Generator > Digital Modulation Off On to On. This generates a
custom arbitrary waveform for use in this procedure. You can also use a previously stored or
downloaded waveform.
2. Press Mode > Dual ARB > Select Waveform and ensure that AUTOGEN_WAVEFORM is highlighted on the
display. AUTOGEN_WAVEFORM is the default name assigned to the waveform you generated in the
previous step.
3. Press Select Waveform. This selects the waveform and returns you to the previous softkey menu.
4. Press ARB Off On to On. The dual Arb player must be turned on to display the CCDF plot in the following
steps.
5. Press ARB Setup > Waveform Utilities > Waveform Statistics and ensure that AUTOGEN_WAVEFORM is
highlighted on the display.
6. Press CCDF Plot and observe the position of the waveform’s curve, which is the darkest line.
7. Press Return > Return > Clipping.
8. Ensure that the Clipping Type |I+jQ| |I|,|Q| softkey is set to |I|,|Q|. This activates the Clip |I| To and
Clip |Q| To softkeys that enable you to configure rectangular (independent) I and Q data clipping.
9. Press Clip |I| To > 80 > %.
10. Press Clip |Q| To > 40 > % > Apply to Waveform. The I and Q data are individually clipped by 80% and
40%, respectively. Once clipping is applied to the waveform it cannot be undone. Repeated use of the
clipping function has a cumulative effect on the waveform.
11. Press Waveform Statistics > CCDF Plot and observe the waveform’s curve. Notice the reduction in
peak-to-average power, relative to the previous plot, after applying clipping.
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Using Waveform Scaling
Using Waveform Scaling
Waveform scaling is used to eliminate DAC over-range errors. The ESG provides two methods of waveform
scaling:
Runtime Scaling
Available in the Dual ARB Player and the Multitone modulation format, this type of
scaling enables you to make real time scaling adjustments of a currently playing
waveform.
Permanent Scaling Available in only the Dual ARB player, this type of scaling permanently scales the data
of a non-playing waveform file residing in volatile memory.
This section describes how DAC over-range errors occur and how you can use waveform scaling to
eliminate these errors effectively.
How DAC Over-Range Errors Occur
The ESG utilizes an interpolator filter in the conversion of the digital I and Q baseband waveforms into
analog waveforms. The clock rate of the interpolator is four times that of the baseband clock. The
interpolator therefore calculates sample points between the incoming baseband samples to equal the faster
clock rate and smooth out the waveform, giving it a more curve-like appearance (see Figure 4-22).
Figure 4-22
Waveform Interpolation
The interpolation filters in the DACs have overshoot. If a baseband waveform has a fast-rising edge, the
interpolator filter’s overshoot or frequency response becomes a component of the interpolated baseband
waveform. This response causes a ripple or ringing effect at the peak of the rising edge. If this ripple exceeds
(or overshoots) the upper limit of the DAC’s range, the interpolator calculates erroneous sample points and
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is unable to replicate the true form of the ripple (see Figure 4-23). As a result, the ESG reports a DAC
over-range error.
Figure 4-23
Waveform Overshoot
How Scaling Eliminates DAC Over-Range Errors
Scaling reduces or shrinks a baseband waveform’s amplitude while maintaining its basic shape and
characteristics, such as peak-to-average power ratio. If the fast-rising baseband waveform is scaled enough
to allow an adequate margin for the overshoot, the interpolator filter is then able to calculate sample points
that include the ripple effect, thereby eliminating the over-range error (see Figure 4-24).
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Figure 4-24
Waveform Scaling
Although scaling maintains the basic shape of the waveform, too much scaling can compromise its integrity
because the bit resolution can be so low that the waveform becomes corrupted with quantization noise.
Maximum accuracy and optimum dynamic range are achieved by scaling the waveform just enough to
remove the DAC over-range error. Optimum scaling varies with waveform content.
Scaling a Currently Playing Waveform (Runtime Scaling)
This section demonstrates how to make real time scaling adjustments to a currently playing waveform. This
type of scaling does not affect the waveform file and is well suited for eliminating DAC over-range errors.
In the Dual ARB Player
To play a waveform in the Dual ARB Player, ensure that the waveform exists in volatile memory. This
procedure first creates a waveform file using the Custom modulation format, which the signal generator
automatically stores in volatile memory.
1. Press Preset > Mode > Custom > Arb Waveform Generator > Digital Modulation Off On to On. This generates a
custom arbitrary waveform for use in this procedure. You can also use a previously stored or
downloaded waveform.
2. Press Mode > Dual ARB > Select Waveform and ensure that AUTOGEN_WAVEFORM is highlighted on the
display. AUTOGEN_WAVEFORM is the default name assigned to the waveform you generated in the
previous step.
3. Press Select Waveform. This selects the waveform and returns you to the previous softkey menu.
4. Press ARB Off On to On. This plays the selected waveform.
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5. Press ARB Setup > More (1 of 2) > Waveform Runtime Scaling and adjust the front panel knob or use the
number keys to enter a new value. The new scaling value is instantly applied to the playing waveform.
Runtime scaling adjustments are not cumulative, as the values are always relative to original amplitude
of the waveform file.
In Multitone
1. Press Preset > Mode > Multitone > Multitone Off On to On. This generates a multitone arbitrary waveform
for use in this procedure.
2. Press More (1 of 2) > ARB Setup > More (1 of 2) > Waveform Runtime Scaling and adjust the front panel knob
or use the number keys to enter a new value. The new scaling value is instantly applied to the playing
waveform. Runtime scaling adjustments are not cumulative, as the values are always relative to original
amplitude of the waveform file.
Scaling a Waveform File in Volatile Memory
This procedure enables you to permanently scale a waveform file. You can then store the scaled waveform
segment to non-volatile memory for future use. Scaling is cumulative and non-reversible.
1. Press Preset > Mode > Custom > Arb Waveform Generator > Digital Modulation Off On to On. This generates a
custom arbitrary waveform for use in this procedure. You can also use a previously stored or
downloaded waveform.
2. Press Mode > Dual ARB > Select Waveform and ensure that AUTOGEN_WAVEFORM is highlighted on the
display. AUTOGEN_WAVEFORM is the default name assigned to the waveform you generated in the
previous step.
3. Press Select Waveform. This selects the waveform and returns you to the previous softkey menu.
4. Press ARB Setup > Waveform Utilities and ensure that AUTOGEN_WAVEFORM is highlighted on the display.
5. Press Scale Waveform Data > Scaling > 70 > % > Apply to Waveform. The waveform is now reduced to 70
percent of its original amplitude. Once this type of scaling is applied to the waveform it cannot be
undone. Repeated scaling applications have a cumulative effect on the waveform.
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Using Customized Burst Shape Curves
Using Customized Burst Shape Curves
You can adjust the shape of the rise time curve and the fall time curve using the Rise Shape and Fall
Shape editors. Each editor allows you to enter up to 256 values, equidistant in time, to define the shape of
the curve. The values are then resampled to create the cubic spline that passes through all of the sample
points.
The Rise Shape and Fall Shape table editors are available for custom real time I/Q baseband generator
waveforms and real time I/Q baseband generator TDMA waveforms. They are not available for waveforms
generated by the dual arbitrary waveform (dual ARB) generator.
For instructions on modifying rise and fall times and delays, see “Configuring the Burst Rise and Fall
Parameters” on page 392.
Understanding Burst Shape
The default burst shape of each format is implemented according to the standards of the format selected. You
can, however, modify the following aspects of the burst shape:
Rise time
the period of time, specified in bits, where the burst increases from
a minimum of −70 dB (0) to full power (1).
Fall time
the period of time, specified in bits, where the burst decreases from
full power (1) to a minimum of −70 dB (0).
Rise delay
the period of time, specified in bits, that the start of the burst rise is
delayed. Rise delay can be either negative or positive. Entering a
delay other than zero shifts the full power point earlier or later than
the beginning of the first useful symbol.
Fall delay
the period of time, specified in bits, that the start of the burst fall is
delayed. Fall delay can be either negative or positive. Entering a
delay other than zero shifts the full power point earlier or later than
the end of the last useful symbol.
User-defined burst shape
up to 256 user-entered values which define the shape of the curve in
the specified rise or fall time. The values can vary between 0 (no
power) and 1 (full power) and are scaled linearly. Once specified,
the values are resampled as necessary to create the cubic spline that
passes through all of the sample points.
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User-Defined
Values
User-Defined
Values
Power
1
0
Rise
Delay
Rise
Time
Fall
Delay
Fall
Time
Time
Burst shape maximum rise and fall time values are affected by the following factors:
•
the symbol rate
•
the modulation type
When the rise and fall delays equal 0, the burst shape is attempting to synchronize the maximum burst shape
power to the beginning of the first valid symbol and the ending of the last valid symbol of the timeslot. The
following figure illustrates a bursted signal in an EDGE frame with a rise delay of 0 and a fall delay of
+1 bit.
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The signal generator firmware computes optimum burst shape based on the settings you’ve chosen for
modulation. You can further optimize burst shape by lining up the data portion with the modulation. For
example, if you’re designing a new modulation scheme, do the following:
•
Adjust the modulation and filtering to set the spectrum you want.
•
Turn on framing.
•
Adjust the burst rise and fall delay and rise and fall time for the timeslots.
If you find that the error vector magnitude (EVM) or adjacent channel power (ACP) increases when you turn
bursting on, you can adjust the burst shape to assist with troubleshooting.
Creating a User-Defined Burst Shape Curve
Using this procedure, you learn how to enter rise shape sample values and mirror them as fall shape values
to create a symmetrical burst curve.
This section teaches you how to perform the following tasks:
•
“Accessing the Table Editors” on page 164
•
“Entering Sample Values” on page 164
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Accessing the Table Editors
1. Press Preset.
2. Perform the following keypress sequence required for your format type.
For Custom Format
Press Mode > Custom > Real Time I/Q Base Band > Burst Shape.
For TMDA Formats
Press Mode > Real Time TDMA > desired format > More (1 of 2) > Modify Standard >
Burst Shape.
3. Press Define User Burst Shape > More (1 of 2) > Delete All Rows > Confirm Delete Of All Rows.
Entering Sample Values
Use the sample values in the following table.
Rise Shape Editor
Sample
Value
Sample
Value
0
0.000000
5
0.900000
1
0.400000
6
0.950000
2
0.600000
7
0.980000
3
0.750000
8
0.990000
4
0.830000
9
1.000000
1. Highlight the value (1.000000) for sample 1.
2. Press .4 > Enter.
3. Press .6 > Enter.
4. Enter the remaining values for samples 3 through 9 from the table above.
5. Press More (2 of 2) > Edit Fall Shape > Load Mirror Image of Rise Shape >
Confirm Load Mirror Image Of Rise Shape.
This changes the fall shape values to a mirror image of the rise shape values, as shown in Figure 4-25 on
page 165.
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Figure 4-25
Display the Burst Shape
Press More (1 of 2) > Display Burst Shape.
This displays a graphical representation of the waveform’s rise and fall characteristics, as shown in Figure
4-26.
Figure 4-26
To return the burst to the default conditions, press the following keys:
Return > Return > Confirm Exit From Table Without Saving > Restore Default Burst Shape.
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Storing a User-Defined Burst Shape Curve
1. Press Define User Burst Shape > More (1 of 2) > Load/Store > Store To File.
If there is already a file name from the Catalog of SHAPE Files occupying the active entry
area, press the following keys:
Editing Keys > Clear Text
2. Enter a file name (for example, NEWBURST) using the alpha keys and the numeric keypad.
The maximum file name length is 23 characters (alphanumeric and special characters).
3. Press Enter.
The contents of the current Rise Shape and Fall Shape table editors are stored to the Catalog of
SHAPE Files. This burst shape can now be used to customize a modulation or as a basis for a new burst
shape design.
Recalling a User-Defined Burst Shape Curve
Once a user-defined burst shape file is stored in memory, it can be recalled for use with real time I/Q
baseband generated digital modulation.
This example requires a user-defined burst shape file stored in memory. If you have not created and stored a
user-defined burst shape file, complete the steps in the previous sections, “Creating a User-Defined Burst
Shape Curve” on page 163 and “Storing a User-Defined Burst Shape Curve” on page 166.
1. Press Preset.
2. Perform the following keypress sequence required for your format type.
For Custom Format
Press Mode > Custom > Real Time I/Q Base Band > Burst Shape > Burst Shape Type > User File.
For TMDA Formats
Press Mode > Real Time TDMA > desired format > More (1 of 2) > Modify Standard >
Burst Shape > Burst Shape Type > User File.
3. Highlight the desired burst shape file (for example, NEWBURST).
4. Press Select File.
The selected burst shape file is now applied to the current real time I/Q baseband digital modulation
state.
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Generating the Waveform
Perform the following keypress sequence required for your format type.
For Custom Format
Press Return > Custom Off On.
For TMDA Formats
Press Return > Return > More (2 of 2) > desired format Off On.
This generates the custom modulation or TDMA state with user-defined burst shape created in the previous
sections. During waveform generation, the CUSTOM (or appropriate TDMA) annunciator and I/Q
annunciator activate. The waveform is now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 800 MHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off.
The current real time I/Q baseband digital modulation format with user-defined burst shape is now available
at the signal generator’s RF OUTPUT connector.
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Using Finite Impulse Response (FIR) Filters
Using Finite Impulse Response (FIR) Filters
Finite Impulse Response filters can be created and used with both dual arbitrary waveform generated
waveforms and real time baseband generated waveforms. For this example, the filter is defined within the
CDMA2000 digital communications format, a dual arbitrary waveform generated state.
Creating a User-Defined FIR Filter Using the FIR Table Editor
In this procedure, you use the FIR Values table editor to create and store an 8-symbol, windowed sync
function filter with an oversample ratio of 4.
Accessing the Table Editor
1. Press Preset.
2. Press Mode > CDMA > Arb CDMA2000.
3. Press More (1 of 2) > CDMA2000 Define > Filter > Define User FIR.
4. Press More (1 of 2) > Delete All Rows.
This will initialize the table editor as shown in Figure 4-27.
Figure 4-27
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Entering the Coefficient Values
1. Press the Return softkey to get to the first page of the table editor.
2. Use the cursor to highlight the Value field for coefficient 0, then press Edit Item.
3. Use the numeric keypad to type the first value (−0.000076) from Table 4-1. As you press the numeric
keys, the numbers are displayed in the active entry area. (If you make a mistake, you can correct it using
the backspace key.)
4. Continue entering the coefficient values from the table in step 1 until all 16 values have been entered.
Table 4-1
Coefficient
Value
Coefficient
Value
0
−0.000076
8
−0.035667
1
−0.001747
9
−0.116753
2
−0.005144
10
−0.157348
3
−0.004424
11
−0.088484
4
0.007745
12
0.123414
5
0.029610
13
0.442748
6
0.043940
14
0.767329
7
0.025852
15
0.972149
Duplicating the First 16 Coefficients Using Mirror Table
In a windowed sinc function filter, the second half of the coefficients are identical to the first half in reverse
order. The signal generator provides a mirror table function that automatically duplicates the existing
coefficient values in the reverse order.
1. Press Mirror Table. The last 16 coefficients (16 through 31) are automatically generated and the first of
these coefficients (number 16) highlights, as shown in Figure 4-28 on page 170.
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Figure 4-28
Setting the Oversample Ratio
The oversample ratio (OSR) is the number of filter coefficients per symbol. Acceptable values range from 1
through 32; the maximum combination of symbols and oversampling ratio allowed by the table editor is
1024. The instrument hardware, however, is actually limited to 32 symbols, an oversample ratio between 4
and 16, and 512 coefficients. So if you enter more than 32 symbols or 512 coefficients, the instrument is
unable to use the filter. If the oversample ratio is different from the internal, optimally selected one, then the
filter is automatically resampled to an optimal oversample ratio.
For this example, the desired OSR is 4, which is the default, so no action is necessary.
Displaying a Graphical Representation of the Filter
The signal generator has the capability of graphically displaying the filter in both time and frequency
dimensions.
1. Press More (1 of 2) > Display FFT (fast Fourier transform).
Refer to Figure 4-29 on page 171.
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Figure 4-29
2. Press Return.
3. Press Display Impulse Response.
Refer to Figure 4-30.
Figure 4-30
4.
Press Return to return to the menu keys.
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Storing the Filter to Memory
Use the following steps to store the file.
1. Press Load/Store > Store To File. The catalog of FIR files appears along with the amount of memory
available.
2. As described in “Storing a Component Test Waveform to Memory” on page 320, name and store this
file as FIR_1.
The FIR_1 file is the first file name listed. (If you have previously stored other FIR files, additional file
names are listed below FIR_1.) The file type is FIR and the size of the file is 260 bytes. The amount of
memory used is also displayed. The number of files that can be saved depends on the size of the files and the
amount of memory used. Refer to Figure 4-31.
Figure 4-31
Memory is also shared by instrument state files and list sweep files.
This filter can now be used to customize a modulation or it can be used as a basis for a new filter design.
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Modifying a FIR Filter Using the FIR Table Editor
Modifying a FIR Filter Using the FIR Table Editor
FIR filters stored in signal generator memory can easily be modified using the FIR table editor. You can load
the FIR table editor with coefficient values from user-defined FIR files stored in non-volatile memory or
from one of the default FIR filters. Then you can modify the values and store the new files.
Loading the Default Gaussian FIR File
1. Press Preset.
2. Press Mode > CDMA > Arb CDMA2000 > More (1 of 2) > CDMA2000 Define.
3. Press Filter > Define User FIR > More (1 of 2) > Load Default FIR > Gaussian.
4. Press Filter BbT > 0.300 > Enter.
5. Press Filter Symbols > 8 > Enter.
6. Press Generate.
NOTE
The actual oversample ratio during modulation is automatically selected by the instrument.
A value between 4 and 16 is chosen dependent on the symbol rate, the number of bits per
symbol of the modulation type, and the number of symbols.
7. Press Display Impulse Response (refer to Figure 4-32).
Figure 4-32
8. Press Return.
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Modifying a FIR Filter Using the FIR Table Editor
Modifying the Coefficients
1. Using the front panel arrow keys, highlight coefficient 15.
2. Press 0 > Enter.
3. Press Display Impulse Response.
Figure 4-33
Refer to Figure 4-33 on page 174. The graphic display can provide a useful troubleshooting tool (in this
case, it indicates that a coefficient value is missing, resulting in an improper Gaussian response).
4. Press Return.
5. Press More (2 of 2).
6. Highlight coefficient 15.
7. Press 1 > Enter.
Storing the Filter to Memory
The maximum file name length is 23 characters (alphanumeric and special characters).
1. Press Load/Store > Store To File.
2. Name the file NEWFIR2.
3. Press Enter.
The contents of the current FIR table editor are stored to a file in non-volatile memory and the catalog of FIR
files is updated to show the new file.
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Differential Encoding
Differential Encoding
Differential encoding is a digital-encoding technique whereby a binary value is denoted by a signal change
rather than a particular signal state. Using differential encoding, binary data in any user-defined I/Q or FSK
modulation can be encoded during the modulation process via symbol table offsets defined in the
Differential State Map.
For example, consider the signal generator’s default 4QAM I/Q modulation. With a user-defined modulation
based on the default 4QAM template, the I/Q Values table editor contains data that represent four
symbols (00, 01, 10, and 11) mapped into the I/Q plane using two distinct values, 1.000000 and −1.000000.
These four symbols can be differentially encoded during the modulation process by assigning symbol table
offset values associated with each data value. The following illustration shows the 4QAM modulation in the
I/Q Values table editor.
NOTE
The number of bits per symbol can be expressed using the following formula. Because the
equation is a ceiling function, if the value of x contains a fraction, x is rounded up to the
next whole number.
Where x = bits per symbol, and y = the number of differential states.
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Differential Encoding
The following illustration shows a 4QAM modulation I/Q State Map.
2nd Symbol
Data = 00000001
Distinct values: -1, +1
1st Symbol
Data = 00000000
Distinct values: +1, +1
2
1
3
4
3rd Symbol
Data = 00000010
Distinct values: -1, -1
4th Symbol
Data = 00000011
Distinct values: +1, -1
Differential Data Encoding
In real time I/Q baseband digital modulation waveforms, data (1’s and 0’s) are encoded, modulated onto a
carrier frequency, and subsequently transmitted to a receiver. In contrast to differential encoding (described
on page 175), differential data encoding modifies the data stream prior to I/Q mapping. Where differential
encoding encodes the raw data by using symbol table offset values to manipulate I/Q mapping at the point of
modulation, differential data encoding uses the transition from one bit value to another to encode the raw
data.
Differential data encoding modifies the raw digitized data by creating a secondary, encoded data stream that
is defined by changes in the digital state, from 1 to 0 or from 0 to 1, of the raw data stream. This
differentially encoded data stream is then modulated and transmitted.
In differential data encoding, a change in a raw data bit’s digital state, from 1 to 0 or from 0 to 1, produces a
1 in the encoded data stream. No change in digital state from one bit to the next, in other words a bit with a
value of 1 followed by another bit with a value of 1 or a bit with a value of 0 followed by the same, produces
a 0 in the encoded data. For instance, differentially encoding the data stream containing 01010011001010
renders 1111010101111.
Differential data encoding can be described by the following equation:
transmittedbit ( i ) = databit ( i – 1 ) ⊕ databit ( i )
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For a bit-by-bit illustration of the encoding process, see the following illustration.
0 1 0 1 0 0 1 1 0 0 1 0 1
raw (unencoded) data
change =
no change =
1 1 1 1 0 1 0 1 0 1 1 1 1
differentially encoded data
How Differential Encoding Works
Differential encoding employs offsets in the symbol table to encode user-defined modulation schemes. The
Differential State Map table editor is used to introduce symbol table offset values which in turn
cause transitions through the I/Q State Map based on their associated data value. Whenever a data value is
modulated, the offset value stored in the Differential State Map is used to encode the data by transitioning
through the I/Q State Map in a direction and distance defined by the symbol table offset value.
Entering a value of +1 will cause a 1-state forward transition through the I/Q State Map, as shown in the
following illustration.
NOTE
The following I/Q State Map illustrations show all of the possible state transitions using a
particular symbol table offset value. The actual state-to-state transition would depend upon
the state in which the modulation had started.
As an example, consider the following data/symbol table offset values.
Table 4-2
Data
Offset Value
00000000
+1
00000001
-1
00000010
+2
00000011
0
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Differential Encoding
These symbol table offsets will result in one of the transitions, as shown.
Data Value 00000000
with Symbol Table Offset +1
transition 1 state forward
Data Value 00000010
with Symbol Table Offset +2
transition 2 states forward
Data Value 00000001
with Symbol Table Offset -1
transition 1 state backward
Data Value 00000011
with Symbol Table Offset 0
no transition
When applied to the user-defined default 4QAM I/Q map, starting from the 1st symbol (data 00), the
differential encoding transitions for the data stream (in 2-bit symbols) 0011100001 appear in the following
illustration.
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Differential Encoding
1st
1st Symbol
3rd Symbol
{
{
{
2nd
5th Symbol
2nd Symbol
5th
3rd
{
{
Data = 0011100001
4th Symbol
4th
Data Value
00
01
10
11
Symbol Table Offset
+1
-1
+2
+0
As you can see from the previous illustration, the 1st and 4th symbols, having the same data value (00),
produce the same state transition (forward 1 state). In differential encoding, symbol values do not define
location; they define the direction and distance of a transition through the I/Q State Map.
For instructions on configuring differential encoding, see “Using Differential Encoding” on page 179.
Using Differential Encoding
Differential encoding is a digital-encoding technique that denotes a binary value by a signal change rather
than a particular signal state. It is available for custom real time I/Q baseband generator waveforms and real
time I/Q baseband generator TDMA waveforms. It is not available for waveforms generated by the dual
arbitrary waveform generator.
The signal generator’s Differential State Map table editor enables you to modify the differential
state map associated with user-defined I/Q and user-defined FSK modulations. In this procedure, you create
a user-defined I/Q modulation and then configure, activate, and apply differential encoding to the
user-defined modulation. For more information, see “Differential Encoding” on page 175.
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Configuring User-Defined I/Q Modulation
1. Press Preset.
2. Perform the following keypress sequence required for your format type.
For Custom Format
Press Mode > Custom > Real Time I/Q Base Band > Modulation Type > Define User I/Q >
More (1 of 2) > Load Default I/Q Map > QAM > 4QAM
For TMDA Formats
Press Mode > Real Time TDMA > desired format > More (1 of 2) > Modify Standard >
Modulation Type > Define User I/Q > More (1 of 2) > Load Default I/Q Map > QAM > 4QAM
This loads a default 4QAM I/Q modulation and displays it in the I/Q table editor.
The default 4QAM I/Q modulation contains data that represent 4 symbols (00, 01, 10, and 11) mapped into
the I/Q plane using 2 distinct values (1.000000 and −1.000000). These 4 symbols will be traversed during
the modulation process by the symbol table offset values associated with each symbol of data. Refer to
Figure 4-34.
Figure 4-34
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Differential Encoding
Accessing the Differential State Map Table Editor
Press Configure Differential Encoding.
This opens the Differential State Map table editor, as shown. At this point, you see the data for the
1st symbol (00000000) and the cursor prepared to accept an offset value.You are now prepared to create a
custom differential encoding for the user-defined default 4QAM I/Q modulation. Refer to Figure 4-35 on
page 181.
Figure 4-35
Data
Symbol Table Offset Values Entry Area
Editing the Differential State Map
1. Press 1 > Enter.
This encodes the first symbol by adding a symbol table offset of 1. The symbol rotates forward through
the state map by 1 value when a data value of 0 is modulated.
2. Press +/- > 1 > Enter.
This encodes the second symbol by adding a symbol table offset of −1. The symbol rotates backward
through the state map by 1 value when a data value of 1 is modulated.
NOTE
Chapter 4
At this point, the modulation has one bit per symbol. For the first two data values
(00000000 and 00000001) only the last bits (the 0 and the 1, respectively) are significant.
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3. Press 2 > Enter.
This encodes the third symbol by adding a symbol table offset of 2. The symbol rotates forward through
the state map by 2 values when a data value of 10 is modulated.
4. Press 0 > Enter.
This encodes the fourth symbol by adding a symbol table offset of 0. The symbol does not rotate through
the state map when a data value of 11 is modulated.
NOTE
At this point, the modulation has two bits per symbol. For the data values 00000000,
00000001, 00000010, 00000011, the symbol values are 00, 01, 10, and 11 respectively.
Applying Custom Differential Encoding
Press Return > Differential Encoding Off On.
This applies the custom differential encoding to a user-defined modulation.
NOTE
Notice that (UNSTORED) appears next to Differential State Map on the signal
generator’s display. Differential state maps are associated with the user-defined modulation
for which they were created.
In order to save a custom differential state map, you must store the user-defined modulation
for which it was designed. Otherwise the symbol table offset data is purged when you press
the Confirm Exit From Table Without Saving softkey when exiting from the I/Q or FSK table
editor.
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User-Defined I/Q Maps
User-Defined I/Q Maps
In modulation schemes defined by standards (such as TDMA and CDMA), symbols appear in default
positions in the I/Q plane. Using the I/Q Values table editor, you can define your own symbol map by
changing the position of one or more symbols. The I/Q Values is available for custom real time I/Q
baseband generator waveforms and real time I/Q baseband generator TDMA waveforms. It is not available
for waveforms generated by the dual ARB waveform generator.
Creating a User-Defined I/Q Map
This section teaches you how to perform the following tasks:
•
“Accessing and Clearing the I/Q Table Editor” on page 183
•
“Entering I and Q Values” on page 184
•
“Displaying the I/Q Map” on page 184
Use the following procedure to create and store a 4-symbol unbalanced QPSK modulation.
Accessing and Clearing the I/Q Table Editor
1. Press Preset.
2. Perform the following keypress sequence required for your format type.
For Custom Format
Press Mode > Custom > Real Time I/Q Base Band > Modulation Type > Define User I/Q >
More (1 of 2) > Delete All Rows > Confirm Delete All Rows.
For TMDA Formats
Press Mode > TDMA > desired format > More (1 of 2) > Modify Standard > Modulation Type > Define User I/Q >
More (1 of 2) > Delete All Rows > Confirm Delete All Rows.
This loads a default 4QAM I/Q modulation and clears the I/Q Values table editor.
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User-Defined I/Q Maps
Entering I and Q Values
Enter the I and Q values listed in the following table.
Symbol
Data Bits
I Value
Q Value
0
0000
0.500000
1.000000
1
0001
−0.500000
1.000000
2
0010
0.500000
−1.000000
3
0011
−0.500000
−1.000000
1. Press .5 > Enter.
2. Press 1 > Enter.
3. Enter the remaining I and Q values.
As the I value updates, the highlight moves to the first Q entry (and provides a default value of 0), and an
empty row of data appears below the first row. As the Q value updates, and the highlight moves to the next I
value. As you press the numeric keys, the numbers display in the active entry area. If you make a mistake,
use the backspace key and then retype.
Also note that 0.000000 appears as the first entry in the list of Distinct Values, and that 0.500000
and 1.000000 are listed as the distinct values.
Displaying the I/Q Map
1. Press Display I/Q Map
An I/Q map generated using the current values in the I/Q Values table editor is displayed.
The map in this example has four symbols. The map uses the following four unique values: 0.5, 1.0,
−0.5, and −1.0 to create the four symbols. It is not the number of values that defines how many symbols
a map has, but how those values are combined.
2. Press Return.
When the contents of a table editor have not been stored, I/Q Values (UNSTORED) appears on the
display. Follow the instructions in the next section to store the custom I/Q table.
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User-Defined I/Q Maps
Storing a User-Defined I/Q Map File
In this example, you learn how to store a user-defined I/Q map. If you have not created a user-defined I/Q
map, complete the steps in the previous sections, “Accessing and Clearing the I/Q Table Editor” on page
183 and “Entering I and Q Values” on page 184.
1. Press More (1 of 2) > Load/Store > Store To File.
If there is already a file name from the Catalog of IQ Files occupying the active entry area, press
the following keys:
Edit Keys > Clear Text
2. Enter a file name (for example, NEW4QAM) using the alpha keys and the numeric keypad.
The maximum file name length is 23 characters.
3. Press Enter.
The user-defined I/Q map is now stored in the Catalog of IQ Files.
Moving I/Q Symbols
Use the following procedure to manipulate symbol locations to simulate magnitude and phase errors. In this
example, you edit a 4QAM constellation to move one symbol closer to the origin.
Loading the Default 4QAM I/Q Map
1. Press Preset.
2. Perform the following keypress sequence required for your format type.
For Custom Format
Press Mode > Custom > Real Time I/Q Base Band > Modulation Type > Define User I/Q >
More (1 of 2) > Load Default I/Q Map > QAM > 4QAM.
For TMDA Formats
Press Mode > TDMA > desired format > More (1 of 2) > Modify Standard > Modulation Type > Define User I/Q >
More (1 of 2) > Load Default I/Q Map > QAM > 4QAM.
This loads a default 4QAM I/Q modulation into the I/Q Values table editor.
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Basic Digital Operation (Option 001/601 or 002/602)
User-Defined I/Q Maps
Editing I and Q Values
1. Press .235702 > Enter.
2. Press .235702 > Enter.
As you enter the numbers using the numeric keypad, they are displayed in the active entry area. If you
make a mistake, use the backspace key and then retype. The I value updates and the highlight moves to
the first Q entry. Next, the Q value updates and the highlight moves to the following I entry.
Displaying the I/Q Map
Press More (2 of 2) > Display I/Q Map.
Note that one symbol has moved, as shown.
For instructions on storing this modified I/Q map to the signal generator’s memory catalog, see “Storing a
User-Defined I/Q Map File” on page 185.
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User-Defined FSK Modulation
User-Defined FSK Modulation
Using the Frequency Values table editor, you can define, modify and store user-defined frequency shift
keying modulation.
The Frequency Values table editor is available for custom real time I/Q baseband generator waveforms
and real time I/Q baseband generator TDMA waveforms. It is not available for waveforms generated by the
dual arbitrary waveform generator.
Modifying a Default FSK Modulation
In this example, you learn how to add errors to a default FSK modulation.
Loading the Default 4-Level FSK
1. Press Preset.
2. Perform the following keypress sequence required for your format type.
For Custom Format
Press Mode > Custom > Real Time I/Q Base Band > Modulation Type > Define User FSK >
More (1 of 2) > Load Default FSK.
For TMDA Formats
Press Mode > TDMA > desired format > More (1 of 2) > Modify Standard > Modulation Type > Define User FSK >
More (1 of 2) > Load Default FSK.
3. Press Freq Dev > 1.8 > kHz.
4. Press 4-Lvl FSK.
This sets the frequency deviation and opens the Frequency Values table editor with the 4-level FSK
default values displayed. The frequency value for data 0000 is highlighted.
Modifying Frequency Deviation Values
1. Press -1.81 > kHz.
2. Press -590 > Hz.
3. Press 1.805 > kHz.
4. Press 610 > Hz.
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User-Defined FSK Modulation
As you modify the frequency deviation values, the cursor moves to the next data row. An unstored file of
frequency deviation values is created for your custom 4-level FSK file. For instructions on storing the file,
see the next section.
Storing an FSK Modulation
In this example, you learn how to store an FSK modulation. If you have not created an FSK
modulation, complete the steps in the previous section, “Modifying a Default FSK Modulation” on page
187.
1. Press Load/Store > Store To File.
If there is already a file name from the Catalog of FSK Files occupying the active entry area, press
the following keys:
Edit Keys > Clear Text
2. Enter a file name (for example, NEWFSK) using the alpha keys and the numeric keypad.
3. Press Enter.
The user-defined FSK modulation is now stored in the Catalog of FSK Files.
Creating a User-Defined FSK Modulation
Accessing and Clearing the Table Editor
1. Press Preset.
2. Perform the following keypress sequence required for your format type.
For Custom Format
Press Mode > Custom > Real Time I/Q Base Band > Modulation Type > Define User FSK >
More (1 of 2) > Delete All Rows > Confirm Delete All Rows.
For TMDA Formats
Press Mode > TDMA > desired format > More (1 of 2) > Modify Standard > Modulation Type > Define User FSK >
More (1 of 2) > Delete All Rows > Confirm Delete All Rows.
This accesses the Frequency Values table editor and clears the previous values.
Entering Frequency Deviation Values
1. Press 600 > Hz.
2. Press 1.8 > kHz.
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User-Defined FSK Modulation
3. Press -600 > Hz.
4. Press -1.8 > kHz.
This sets the frequency deviation for data 0000, 0001, 0010, and 0011 to configure a user-defined FSK
modulation. Each time you enter a value, the Data column increments to the next binary number, up to a
total of 16 data values (from 0000 to 1111).
For instructions on storing this user-defined FSK modulation to the memory catalog, see “Storing an FSK
Modulation” on page 188.
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Creating and Using Bit Files
Creating and Using Bit Files
This procedure teaches you how to use the Bit File Editor to create, edit, and store user-defined files
for data transmission within real time I/Q baseband generated modulation. For this example, a user file is
defined within a custom digital communications format.
User files (user-defined data files) can be created on a remote computer and moved to the signal generator
for subsequent modification, or they can be created and modified using the signal generator’s Bit File
Editor.
These user files can then be applied as the transmitted data within a framed TDMA modulation, transmitted
as a continuous unframed data stream according to the protocol of the active TDMA format, transmitted as
the data for a custom modulation or real time CDMA format, or for GPS applications. User files are not
available for signals generated by the dual ARB waveform generator.
A real time digital modulation personality must be selected when desired real time format appears in the
key press path.
NOTE
For information on creating user-defined data files on a remote computer, see the
E4428C/38C ESG Signal Generator Programming Guide.
Creating a User File
Accessing the Table Editor
1. Press Preset.
2. Press Mode > desired real time format > Data > User File > Create File.
This opens the Bit File Editor. The Bit File Editor contains three columns: Offset,
Binary Data, and Hex Data, as well as cursor position (Position) and file name (Name) indicators,
as shown in the following figure.
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Creating and Using Bit Files
Offset
(in Hex)
NOTE
Chapter 4
Bit Data
Cursor
Position
indicator
(in Hex)
Hexadecimal Data
File Name indicator
When you create new file, the default name appears as UNTITLED, or UNTITLED1, and so
forth. This prevents overwriting previous files.
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Creating and Using Bit Files
Entering Bit Values
1. Refer to the following figure.
Enter These Bit Values
Cursor
Position
Indicator
Hexadecimal Data
2. Enter the 32 bit values shown.
Bit data is entered into the table editor in 1-bit format. The current hexadecimal value of the binary data is
shown in the Hex Data column, and the cursor position (in hexadecimal) is shown in the Position
indicator.
Renaming and Saving a User File
In this example, you learn how to store a user file. If you have not created a user file, complete the steps in
the previous section, “Creating a User File” on page 190.
1. Press More (1 of 2) > Rename > Editing Keys > Clear Text.
2. Enter a file name (for example, USER1) using the alpha keys and the numeric keypad.
3. Press Enter.
The user file has now been renamed and stored to the Bit memory catalog with the name USER1.
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Creating and Using Bit Files
Recalling a User File
In this example, you learn how to recall a user-defined data file from the memory catalog. If you have not
created and stored a user-defined data file, complete the steps in the previous sections, “Creating a User
File” on page 190 and “Renaming and Saving a User File” on page 192.
1. Press Preset.
2. Press Mode > desired real time format > Data > User File.
3. Highlight the file USER1.
4. Press Edit File.
The Bit File Editor opens the file USER1.
Modifying an Existing User File
In this example, you learn how to modify an existing user-defined data file. If you have not created, stored,
and recalled a user-defined data file, complete the steps in the previous sections, “Creating a User File” on
page 190, “Renaming and Saving a User File” on page 192 and “Recalling a User File” on page 193.
Navigating the Bit Values
Press Goto > 4 > C > Enter.
This moves the cursor to bit position 4C in the table, as shown in the following figure.
Cursor moves to new position
Chapter 4
Position indicator changes
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Creating and Using Bit Files
Inverting Bit Values
1. Press 1011.
This inverts the bit values that are positioned 4C through 4F. Notice that hex data in this row has now
changed to 76DB6DB6, as shown in the following figure.
Bits 4C through 4F inverted
Hex Data changed
Applying Bit Errors to a User File
In this example, you learn how to apply bit errors to a user-defined data file. If you have not created and
stored a user-defined data file, complete the steps in the previous sections, “Creating a User File” on page
190 and “Renaming and Saving a User File” on page 192.
1. Press Apply Bit Errors.
2. Press Bit Errors > 5 > Enter.
3. Press Apply Bit Errors.
Notice both Bit Errors softkeys change value as they are linked.
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Waveform Licensing for Firmware Version ≥ C.05.23
Waveform Licensing for Firmware Version ≥ C.05.23
Waveform licensing enables you to license waveforms that you generate and download from any N76xxB
Signal Studio application for unlimited playback in a signal generator. Each licensing option allows you to
permanently license up to five waveforms (Options 221-229) or up to 50 waveforms (Options 250-259) of
your choice. Waveform Options 22x and 25x are perpetual fixed waveform licenses.
Waveforms licensed with Options 221-229 or Options 250-259 cannot be exchanged for different
waveforms. Once a waveform is licensed, that license is permanent and cannot be revoked or replaced.
Option 22x and 25x waveform licenses are signal generator specific (i.e. signal generator serial number
specific). If a licensed Option 22x or Option 25x waveform file is transferred to another signal generator, the
file must be licensed by a separate Option 22x or Option 25x that is in the other signal generator before it can
be played.
To redeem Options 22x or Options 25x, refer to the E4438C–2xx Entitlement Certificate that comes with
your order. For more information on extracting and downloading waveform files, refer to the Programming
Guide.
Understanding Waveform Licensing
Use any N76xxB Signal Studio software to build and download waveforms to the signal generator. Each
Option 22x provides 5 available slots and each Option 25x license provides 50 available slots where you can
add and play waveforms for a trial period of 48 hours per slot. During this time, you can replace the
waveform any number of times until you are satisfied with it. After the trial period expires, the waveform in
the slot is no longer playable until the slot is locked for permanent playback; however, you can replace the
waveform in the slot with another waveform of your choice before locking the slot.
To license additional waveforms that exceed the number permitted by an Option 22x or Option 25x, you
must purchase another Option 22x or Option 25x that you do not already own. For example, if you already
own Option 250, purchase Option 251 to add an additional 50 slots. Adding all 25x options (250-259)
provides a maximum of 500 slots. Adding all 22x options (221-229) provides a maximum of 45 slots.
Repurchasing the same option for the same signal generator, gives you no additional waveform licenses.
Installing an E4438C Option 22x or E4438C Option 25x
Load a Waveform License, E4438C Option 22x or E4438C Option 25x, into the signal generator using
License Manager. For more information on loading the Waveform License, refer to the E4438C-2xx
Entitlement Certificate.
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Waveform Licensing for Firmware Version ≥ C.05.23
Licensing a Signal Generator Waveform File
The following steps add or replace a waveform file to a license slot and lock the slot for permanent
playback.
1. Press Mode > Dual ARB > Waveform Utilities > Waveform Licensing.
2. The signal generator displays a catalog of files labeled either: NVWFM or WFM1. Select the catalog that
contains the desired waveform using the Catalog Type softkey.
3. Use the arrow keys to highlight and select the file to be licensed.
4. Press Add Waveform To First Available Slot to add the selected waveform to the first available slot. The
waveform will play and can be replaced during the 48 hour trial period. To play the waveform beyond
the trial period, the waveform slot must be locked.
5. Press Replace Waveform In Slot to replace a waveform during the 48 hour trial.
6. License the waveform:
a. Press Lock Waveform In Slot.
A warning is displayed:
*** Waveform Lock Warning!!! *** Once a waveform is locked it will use up
an available license slot and it can not be un-locked. Be sure that you
want to lock this waveform.
If necessary, verify that you have selected the correct waveform you want for licensing by pressing
Return.
b. Press Confirm Locking Waveform.
The licensing status of the slot will be changed to Locked MM/DD/YY.
c. If the waveform has not been previously backed up in internal storage, a warning is displayed:
*** Waveform Backup Required!!! ***
d. Make a backup copy of this waveform on a computer before pressing Backup Waveform to Int Storage.
(If the waveform is lost or deleted in the signal generator, it can not be recovered.).
NOTE
196
It is important to make a backup copy of any waveforms that you are licensing and store
them on a computer. Do not store the backup copy on the signal generator. If all of the
copies of the waveforms are deleted or lost, then there is no way to recover the waveform or
reassign the license.
Chapter 4
Basic Digital Operation (Option 001/601 or 002/602)
Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version < C.05.23
Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version
< C.05.23
Waveform 5-Pack licensing enables you to create, generate, and permanently license up to 45 Signal Studio
waveforms. Each Option 22x (Option 221, 222, 223, ...229) enables licensing of five waveforms.
Use the signal generator to manage the licensing of these waveforms. For example, you can use the signal
generator to select individual waveforms for licensing and you can view a list of all currently licensed
waveforms.
Understanding Waveform 5-Pack Licensing
Waveforms licensed with 5-Pack cannot be exchanged. Once a waveform is licensed, that license is
permanent and cannot be revoked or replaced. Option 22x waveforms are licensed to specific signal
generators (i.e. signal generator serial number specific).
Waveform 5-Pack licensing enables you to create and generate signals which can be saved for unlimited use
in a signal generator (i.e. Waveform 5-Pack Option 22x is a perpetual fixed waveform license).
Use the Signal Studio software to build and download waveforms to the signal generator’s volatile memory
to be played. When you are satisfied with the waveform, it must be stored to non-volatile memory before it
can be licensed.
If a licensed Option 22x waveform file is transferred to another signal generator, the file must be licensed by
a separate Option 22x that is in the other signal generator before it can be played. For more information on
extracting and downloading waveform files, refer to the Programming Guide.
To license additional waveforms that exceed the number permitted by an Option 22x, you must purchase an
Option 22x that you do not already own. For example if you already own Option 221 with only two
remaining licenses and you need ten more waveforms, purchase Options 222 and 223 to have enough
licenses to license ten more waveforms. This would leave two remaining licenses on Option 223.
(Repurchasing Option 221 a second time, for the same signal generator, gives you no additional Waveform
5-Pack licenses.)
After licensing a waveform, you can make copies of the waveform using different file names for use on the
same signal generator and even rename the original file without affecting the waveform license.
You can also use the Option 22x to license waveforms from N76xxB Signal Studio software downloaded
during its 14-day free trial license. All of the N76xxB Signal Studio software products provide a 14-day trial
license. This license lets you download and play back waveforms during the 14-day trial period. These
waveforms are denoted by the TRL in the status message area of the waveform segment catalog. After the
trial period expires, the TRL message is removed but the waveform remains. You can license these
waveforms after the TRL message is gone.
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Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version < C.05.23
Waveform 5-Pack requires firmware version ≥ C.04.95.
Installing an E4438C Option 22x Waveform 5-Pack License
1. Load a Waveform 5-Pack license, E4438C Option 22x, into the signal generator using License Manager.
For more information on loading the Waveform 5-Pack License, refer to the E4438C-22x Entitlement
Certificate.
2. Cycle the power on the signal generator.
NOTE
Anytime a new Option 22x is installed on the signal generator, you must cycle power on the
signal generator to enable the Waveform 5-Pack License and to activate the 5-Pack License
softkey.
Licensing a Signal Generator Waveform File
1. Create the waveform:
a. Download any of the N76xxB Signal Studio software that interests you. For downloading N76xxB
Signal Studio software, refer to the E4438C-22x Entitlement Certificate.
b. Create and download a waveform to a signal generator using any of the N76xxB Signal Studio
Software. Refer to your Signal Studio Software Help.
2. Save the file to NVWFM memory:
Before you can license a waveform with the Waveform 5-Pack licensing, the waveform must be saved in
the non-volatile memory (NVWFM).
a. Press Local > Mode > Dual ARB > Waveform Segments > Load Store to Store.
b. Use the arrow keys to highlight the file to be licensed.
c. Press Store Segment to NVWFM Memory.
3. License the waveform:
a. Press Return > ARB Setup > Waveform Utilities > 5-Pack Licensing > Add Waveforms to 5-Pack.
The signal generator displays a catalog of files labeled: Catalog of WFM1 Files.
b. Use the arrow keys to highlight the file to be licensed.
c. Press Add Waveform.
A warning is displayed. See Figure 4-36.
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Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version < C.05.23
Figure 4-36
Add Waveform to 5-Pack Softkey Warning Message
If the waveform selected
for licensing has been
verified as the waveform
you want to be licensed,
press Confirm Adding
Waveform To 5-Pack.
Caution! This step
cannot be undone.
This warning message indicates that this is the last chance for verifying
that the waveform being licensed is the one you want. If the waveform
selected has not been verified, press Return and verify the selection.
Important! Always backup licensed
waveforms in a separate place from the
instrument (e.g. computer, etc.).
If necessary, verify that you have selected the correct waveform you want for licensing by pressing
Return. Otherwise continue to the next step.
d. Press Confirm Adding Waveform to 5-Pack.
The display returns to the Catalog of WFM1 Files and the file’s Status column is now shows
5-Pack Licensed. See Table 4-3.
Table 4-3
Waveform 5-Pack Licensing Status Messages for the “Catalog of Segment Files in
NVWFM Files”
Status Message
Meaning
Notes
Empty field
If no status message, then waveform is licensable.
Once a Trial (TRL) license expires, the
waveform becomes licensable (i.e. the
status message for the TRL waveform
becomes an empty field).
If a licensed Option 22x waveform file is
downloaded to another E4438C signal
generator, the waveform becomes
licensable on that other signal generator
(i.e. the status message field is empty).
5-Pack Licensed
This waveform is licensed by Option 22x.
5-Pack License
Not Required
This message applies to:
Any free waveforms provided with the Agilent
ESG (e.g. RAMP_TEST_WFM, and
SINE_TEST_WFM, etc.)
Any customer created waveform
Any waveforms that have a valid license (e.g. Trial
(TRL) licenses, Advanced Design System (ADS),
etc.). Refer to www.agilent.com.
Once a Trial (TRL) license expires, the
waveform becomes licensable (i.e. the
status message for the TRL waveform
becomes an empty field).
If a licensed Option 22x waveform file is
downloaded to another E4438C signal
generator, the waveform becomes
licensable on that other signal generator
(i.e. the status message field is empty).
e. Make a backup copy of this waveform on a computer.
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Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version < C.05.23
NOTE
It is important to make a backup copy of any 5-Pack waveforms and store them on a
computer or other media. Do not store the backup copy on the signal generator. If all of the
copies of the waveforms are deleted or lost, then there is no way to recover the waveform or
reassign the license. Refer to the Programming Guide for information on extracting
waveform files.
Using Waveform 5-Pack History
The Waveform 5-Pack History softkeys can be used to manage the Waveform 5-Pack files on your signal
generator. The 5-Pack History softkeys can be used to:
•
Create a list for a specific Waveform 5-Pack licensed waveform including any renamed files that have
been leveraged from that licensed waveform
•
Create a list of all licensed and unlicensed waveforms on the signal generator
The 5-Pack History softkey is only active, if you have previously stored a Waveform 5-Pack file in
non-volatile memory (NVWFM). The softkey 5-Pack History also tracks the history of licensed waveform
files that may no longer be available in non-volatile memory (e.g. if the waveform file has been deleted from
non-volatile memory, the 5-Pack History softkey remains active). 5-Pack History retains a catalog of the
Redemption Date, Waveform ID, and the Original Filename.
Finding the History of a Waveform 5-Pack License
Use the following procedure to list a catalog of licensed Waveform 5-Pack files in the non-volatile memory
(NVWFM).
1. On the signal generator:
a. Press Mode > Dual ARB > ARB Setup > Waveform Utilities > 5-Pack Licensing > 5-Pack History
b. Use the arrow keys to highlight the cataloged file.
c. Press Find Waveform
The instrument displays a catalog titled “Waveform 5-Pack Search Results”. This catalog
displays a list of all of the files that are copies of the original file that was licensed with the
Waveform 5-Pack licensing.
NOTE
200
If no files are found, you can reload the backup copies that were made in Step e on
page 199.
Chapter 4
Basic Digital Operation (Option 001/601 or 002/602)
Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version < C.05.23
Finding All Waveforms Associated with 5-Pack Licenses
The following procedure displays a catalog of all of the Waveform 5-Pack files in the WFM1 memory, and
the non-volatile storage (NVWFM):
1. On the signal generator:
a. Press Mode > Dual ARB > ARB Setup > Waveform Utilities > 5-Pack Licensing > Find All Waveforms
The instrument displays a catalog titled: Waveform 5-Pack Search Results.
NOTE
Chapter 4
If no files are found, you can reload the backup copies that were made in Step e on
page 199.
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Basic Digital Operation (Option 001/601 or 002/602)
Using Waveform 5-Pack Licensing (Options 221-229) for Firmware Version < C.05.23
Waveform 5-Pack Warning Messages
Figure 4-37
This standard warning is displayed
every time a waveform is selected to
be licensed. This notification indicates
that one of the available “license
slot[s]” is about to be used from Option
22x.
ALWAYS make backup copies
of waveforms in a separate
non-volatile memory in case a
file is deleted or lost from the
instrument’s non-volatile
memory (NVWFM).
This warning is displayed when an
attempt is made to license a waveform
that has not been saved to non-volatile
memory (NVWFM). Waveforms
cannot be licensed unless they have
been stored to non-volatile memory.
Press the Backup Waveform To Int
Storage softkey.
This warning is displayed when there is
insufficient memory or other problems
with the non-volatile memory and the
waveform could not be saved to
non-volatile memory (NVWFM).
This warning is displayed when the file
being licensed is not backed up in
non-volatile memory (NVWFM), but
there is a file already in non-volatile
memory, with the same name.
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Chapter 4
Basic Digital Operation (Option 001/601 or 002/602)
Waveform Licenses (Signal Studio “A” Versions)
Waveform Licenses (Signal Studio “A” Versions)
The waveform license allows waveforms, created on one ESG, to be downloaded to another ESG. These
encrypted waveforms can be played by other ESGs that have the same options and licenses.
A waveform license is written to the signal generator when a software application that generates waveform
data is installed on the PC.
1. Access the Waveform Licenses menu:
Utility > Instrument Adjustments > Instrument Options > Waveform Licenses
The following is an example of the signal generator display, which lists any time-limited licenses and
perpetual licenses, the days left on time-limited licenses, and the software description:
Chapter 4
203
Basic Digital Operation (Option 001/601 or 002/602)
Waveform Licenses (Signal Studio “A” Versions)
204
Chapter 4
5
AWGN Waveform Generator (Option 403)
This chapter contains examples for using the additive white gaussian noise (AWGN) waveform generator.
Option 403 is only available on the E4438C Vector Signal Generator with Option 001/601or 002/602. The
following list shows the topics covered in this chapter:
•
“Arb Waveform Generator AWGN” on page 206
•
“Real Time I/Q Baseband AWGN” on page 207
For adding real-time AWGN to waveforms using the Dual ARB player, see “Adding Real Time Noise to a
Dual ARB Waveform (Option 403)” on page 112
205
AWGN Waveform Generator (Option 403)
Configuring the AWGN Generator
Configuring the AWGN Generator
The AWGN (additive white Gaussian noise) generator is available for the Arb Waveform Generator mode
and the Real Time I/Q Baseband mode. The AWGN generator can be configured with user-defined noise
bandwidth, noise waveform length, and noise seed parameters.
•
Bandwidth – the noise bandwidth can be set from 50 kHz to 15 MHz.
•
Waveform Length – the waveform length is the length in samples of the noise waveform. Longer
waveform lengths provide more statistically correct noise waveforms.
•
Noise Seed – the noise seed selection can be either random or fixed. The noise seed determines whether
the noise waveform data is repeatable (using the fixed selection) or random (using the random selection).
When the AWGN generator is active, the AWGN and I/Q annunciators are displayed on the front panel of the
signal generator.
Arb Waveform Generator AWGN
1. Press Preset.
2. Press Mode > More (1 of 2) > AWGN > Arb Waveform Generator AWGN
3. Press Bandwidth > 1.25 > MHz.
4. Press Waveform Length > 131072.
5. Press Noise Seed Fixed Random until Random is highlighted.
This configures a randomly seeded AWGN waveform with a bandwidth of 1.25 MHz and a waveform length
of 131072 bits.
Configuring the RF Output
1. Set the RF output frequency to 500 MHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off.
Generating the Waveform
Press AWGN Off On until On is highlighted.
This generates an AWGN waveform with the parameters defined in the previous procedure. During
waveform generation, the AWGN and I/Q annunciators activate and the AWGN waveform is stored in
volatile ARB memory. The waveform is now modulating the RF carrier.
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AWGN Waveform Generator (Option 403)
Configuring the AWGN Generator
Real Time I/Q Baseband AWGN
1. Press Preset.
2. Press Mode > More (1 of 2) > AWGN > Real Time I/Q Baseband AWGN
3. Press Bandwidth > 10 > MHz.
Configuring the RF Output
1. Set the RF output frequency to 500 MHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off.
Generating the Waveform
Press AWGN Off On until On is highlighted.
This generates an AWGN waveform with the parameters defined in the previous procedure. During
waveform generation, the AWGN and I/Q annunciators activate. The waveform is now modulating the RF
carrier.
Chapter 5
207
AWGN Waveform Generator (Option 403)
Configuring the AWGN Generator
208
Chapter 5
6
Analog Modulation
The following list shows the topics covered in this chapter:
•
“Analog Modulation Waveforms” on page 210
•
“Configuring AM” on page 211
•
“Configuring FM” on page 213
•
“Configuring FM” on page 214
•
“Configuring Pulse Modulation” on page 215
•
“Configuring the LF Output” on page 216
209
Analog Modulation
Analog Modulation Waveforms
Analog Modulation Waveforms
The signal generator can modulate the RF carrier with four types of analog modulation: amplitude,
frequency, phase, and pulse.
Available internal waveforms include:
Sine
sine wave with adjustable amplitude and frequency
Dual-Sine
dual-sine waves with individually adjustable frequencies and a percent-ofpeak-amplitude setting for the second tone (available from function generator only)
Swept-Sine
swept-sine wave with adjustable start and stop frequencies, sweep time, and sweep
trigger settings (available from function generator only)
Triangle
triangle wave with adjustable amplitude and frequency
Ramp
ramp with adjustable amplitude and frequency
Square
square wave with adjustable amplitude and frequency
Noise
noise with adjustable amplitude generated as a peak-to-peak value (RMS value is
approximately 80% of the displayed value)
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Analog Modulation
Configuring AM
Configuring AM
Using these procedures, you will learn how to generate an amplitude-modulated RF carrier.
Setting the Carrier Frequency
1. Press Preset.
2. Press Frequency > 1340 > kHz.
Setting the RF Output Amplitude
Press Amplitude > 0 > dBm.
Setting the AM Depth and Rate
1. Press the AM hardkey.
2. Press AM Depth > 90 > %.
3. Press AM Rate > 10 > kHz.
The signal generator is now configured to output a 0 dBm, amplitude-modulated carrier at 1340 kHz with
the AM depth set to 90% and the AM rate set to 10 kHz. The shape of the waveform is a sine wave (notice
that sine is the default for the AM Waveform softkey).
Turning on Amplitude Modulation
Follow these remaining steps to output the amplitude-modulated signal.
1. Press the AM Off On softkey to On.
2. Press the front panel RF On Off key.
The AM and RF ON annunciators are now displayed. This indicates that you have enabled amplitude
modulation and the signal is now being transmitted from the RF OUTPUT connector.
Chapter 6
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Analog Modulation
Configuring AM
Wideband AM (E4438C)
Wideband AM offers bandwidth (up to 40 MHz) beyond that of standard internal AM (10 kHz) by utilizing
an external modulating signal. The external modulating signal is connected to the front-panel I INPUT
connector.
NOTE
When you select wideband AM and turn it on, the signal generator automatically sets the
I INPUT connector for 50 ohms. This setting is independent of the MUX > I/Q Source
setting, so the I/Q Source setting may differ. If you change the I/Q Source setting while
wideband AM is on, it disables the wideband AM signal. To reenable the signal, turn
wideband AM off and then back on.
The following steps set up wideband AM:
1. Press the AM hardkey.
2. Press AM Path 1 2 WB to WB.
3. Connect an external AM source to the front-panel I INPUT connector and turn the external modulation
on. The maximum I input level is 1 volt rms and 10 volt peak. AM sensitivity is fixed at 0.5V = 100%.
The AM modulation depth is a linear function of the input voltage so that 0.25 V = 50%.
4. Press AM Off On to On.
Refer to the ESG data sheet for AM wideband specifications.
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Analog Modulation
Configuring FM
Configuring FM
Using this procedures, you will learn how to create a frequency-modulated RF carrier.
Setting the RF Output Frequency
1. Press Preset.
2. Press Frequency > 1 > GHz.
Setting the RF Output Amplitude
Press Amplitude > 0 > dBm.
Setting the FM Deviation and Rate
1. Press the FM/ΦM hardkey.
2. Press FM Dev > 75 > kHz.
3. Press FM Rate > 10 > kHz.
The signal generator is now configured to output a 0 dBm, frequency-modulated carrier at 1 GHz with a
75 kHz deviation and a 10 kHz rate. The shape of the waveform is a sine wave. (Notice that sine is the
default for the FM Waveform softkey. Press More (1 of 2) to see the softkey.)
Activating FM
1. Press FM Off On to On.
2. Press RF On/Off.
The FM and RF ON annunciators are now displayed. This indicates that you have enabled frequency
modulation and the signal is now being transmitted from the RF OUTPUT connector.
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213
Analog Modulation
Configuring ΦM
Configuring ΦM
Using this procedures, you will learn how to create a phase-modulated RF carrier.
Setting the RF Output Frequency
1. Press Preset.
2. Press Frequency > 3 > GHz.
Setting the RF Output Amplitude
Press Amplitude > 0 > dBm.
Setting the FM Deviation and Rate
1. Press the FM/ΦM hardkey.
2. Press the FM ΦM softkey.
3. Press FM Dev > .25 > pi rad.
4. Press FM Rate > 10 > kHz.
The signal generator is now configured to output a 0 dBm, phase-modulated carrier at 3 GHz with a 0.25 p
radian deviation and 10 kHz rate. The shape of the waveform is a sine wave. (Notice that sine is the default
for the FM Waveform softkey. Press More (1 of 2) to see the softkey.)
Activating FM
1. Press FM Off On.
2. Press RF On/Off.
The FM and RF ON annunciators are now displayed. This indicates that you have enabled phase modulation
and the signal is now being transmitted from the RF OUTPUT connector.
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Analog Modulation
Configuring Pulse Modulation
Configuring Pulse Modulation
Using the following procedures, you will learn how to create a pulse-modulated RF carrier.
Setting the RF Output Frequency
1. Press Preset.
2. Press Frequency > 2 > GHz.
Setting the RF Output Amplitude
Press Amplitude > 0 > dBm.
Setting the Pulse Period and Width
1. Press Pulse > Pulse Period > 100 > usec.
2. Press Pulse > Pulse Width > 24 > usec.
The signal generator is now configured to output a 0 dBm, pulse-modulated carrier at 2 GHz with a
100-microsecond pulse period and 24-microsecond pulse width. The pulse source is set to Internal Pulse.
(Notice that Internal Pulse is the default for the Pulse Source softkey.)
Activating Pulse Modulation
Follow these remaining steps to output the pulse-modulated signal.
1. Press Pulse Off On to On.
2. Press RF On/Off.
The Pulse and RF ON annunciators are now displayed. This indicates that you have enabled pulse
modulation and the signal is now being transmitted from the RF OUTPUT connector.
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Analog Modulation
Configuring the LF Output
Configuring the LF Output
The signal generator has a low frequency (LF) output. The LF output’s source can be switched between an
internal modulation source or an internal function generator.
Using internal modulation (Internal Monitor) as the LF output source, the LF output provides a replica of the
signal from the internal source that is being used to modulate the RF output. The specific modulation
parameters for this signal are configured through the AM, FM, or FM menus.
Using function generator as the LF output source, the function generator section of the internal modulation
source drives the LF output directly. Frequency and waveform are configured from the LF output menu, not
through the AM, FM, or FM menus. You can select the waveform shape from the following choices:
Sine
sine wave with adjustable amplitude and frequency
Dual-Sine
dual-sine waves with individually adjustable frequencies and a percent-ofpeak-amplitude setting for the second tone (available from function generator only)
Swept-Sine
a swept-sine wave with adjustable start and stop frequencies, sweep time, and sweep
trigger settings (available from function generator only)
Triangle
triangle wave with adjustable amplitude and frequency
Ramp
ramp with adjustable amplitude and frequency
Square
square wave with adjustable amplitude and frequency
Noise
noise with adjustable amplitude generated as a peak-to-peak value (RMS value is
approximately 80% of the displayed value)
DC
direct current with adjustable amplitude
NOTE
The LF Out Off On softkey controls the operating state of the LF output. However when the
LF output source selection is Internal Monitor, you have three ways of controlling the output.
You can use the modulation source (AM, FM, or FM) on/off key, the LF output on/off key,
or the Mod On/Off softkey.
The RF On/Off hardkey does not apply to the LF OUTPUT connector.
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Analog Modulation
Configuring the LF Output
Configuring the LF Output with an Internal Modulation Source
In this example, the internal FM modulation is the LF output source.
NOTE
Internal modulation (Internal Monitor) is the default LF output source.
Configuring the Internal Modulation as the LF Output Source
1. Press Preset.
2. Press the FM/ΦM hardkey.
3. Press FM Dev > 75 > kHz.
4. Press FM Rate > 10 > kHz.
5. Press FM Off On.
You have set up the FM signal with a rate of 10 kHz and 75 kHz of deviation. The FM annunciator is
activated indicating that you have enabled frequency modulation.
Configuring the Low Frequency Output
1. Press the LF Out hardkey.
2. Press LF Out Amplitude > 3 > Vp.
3. Press LF Out Off On.
You have configured the LF output signal for a 3 volt sine wave (default wave form) output which is
frequency modulated using the Internal Monitor source selection (default source).
Chapter 6
217
Analog Modulation
Configuring the LF Output
Configuring the LF Output with a Function Generator Source
In this example, the function generator is the LF output source.
Configuring the Function Generator as the LF Output Source
1. Press Preset.
2. Press the LF Out hardkey.
3. Press LF Out Source > Function Generator.
Configuring the Waveform
1. Press LF Out Waveform > Swept-Sine.
2. Press LF Out Start Freq > 100 > Hz.
3. Press LF Out Stop Freq > 1 > kHz.
4. Press Return > Return.
This returns you to the top LF Output menu.
Configuring the Low Frequency Output
1. Press LF Out Amplitude > 3 > Vp.
This sets the LF output amplitude to 3 Vp.
2. Press LF Out Off On.
The LF output is now transmitting a signal using the function generator that is providing a
3 Vp swept-sine waveform. The waveform is sweeping from 100 Hz to 1 kHz.
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7
Digital Signal Interface Module
This chapter provides information on the N5102A Baseband Studio Digital Signal Interface Module. These
features are available only in E4438C ESG Vector Signal Generators with Options 003/004 and 601/602.
The following list shows the topics covered in this chapter:
•
“Clock Timing” on page 220
•
“Data Types” on page 236
•
“Connecting the Clock Source and the Device Under Test” on page 234
•
“Operating the N5102A Module in Output Mode” on page 238
•
“Operating the N5102A Module in Input Mode” on page 247
219
Digital Signal Interface Module
Clock Timing
Clock Timing
This section describes how clocking for the digital data is provided. Clock timing information and diagrams
are supplied for the different port configurations (serial, parallel, or parallel interleaved data transmission)
and phase and skew settings. All settings for the interface module are available on the signal generator user
interface (UI).
Clock and Sample Rates
A sample is a group of bits where the size of the sample is set using the Word Size softkey. The clock is the
signal that tells when the bits of a sample are valid (in a non-transition state). The clock and sample rates are
displayed in the first-level and data setup softkey menus. The clock rate and sample rate are usually the
same. They will differ when serial mode is selected, or when there are multiple clocks per sample.
Figure 7-1
Data Setup Menu for a Parallel Port Configuration
Least significant bit
Most significant bit
Clock and sample rates
The N5102A module clock rate is set using the Clock Rate softkey and has a range of 1 kHz to
400 MHz. The sample rate is automatically calculated and has a range of 1 kHz to 100 MHz. These ranges
can be smaller depending on logic type, data parameters, and clock configuration.
Maximum Clock Rates
The N5102A module maximum clock rate is dependent on the logic and signal type. Table 7-1 and
Table 7-2 show the warranted rates and the maximum clock rates for the various logic and signal types.
Notice that LVDS in the output mode using an IF signal is the only logic type where the warranted and
maximum rates are the same.
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Digital Signal Interface Module
Clock Timing
Table 7-1
Warranted Parallel Output Level Clock Rates and Maximum Clock Rates
Warranted Level Clock Rates
Maximum Clock Rates (typical)
IQ Signal Type
IF Signal Type1
IQ Signal Type
IF Signal Type
LVTTL and CMOS
100 MHz
100 MHz
150 MHz
150 MHz
LVDS
200 MHz
400 MHz
400 MHz
400 MHz
Logic Type
1. The IF signal type is not available for a serial port configuration.
Table 7-2
Warranted Parallel Input Level Clock Rates and Maximum Clock Rates
Logic Type
Warranted Level Clock Rates
Maximum Clock Rates (typical)
LVTTL and CMOS
100 MHz
100 MHz
LVDS
100 MHz
400 MHz
The levels will degrade above the warranted level clock rates, but they may still be usable.
Serial Port Configuration Clock Rates
For a serial port configuration, the lower clock rate limit is determined by the word size (word size and
sample size are synonymous), while the maximum clock rate limit remains constant at 150 MHz for LVTTL
and CMOS logic types, and 400 MHz for an LVDS logic type.
The reverse is true for the sample rate. The lower sample (word) rate value of 1 kHz remains while the upper
limit of the sample rate varies with the word size. For example, a five-bit sample for an LVTTL or CMOS
logic type yields the following values in serial mode:
•
Clock rate of 5 kHz through 150 MHz
•
Sample rate of 1 kHz through 30 MHz
Refer to Table 7-3 and Table 7-4, for the serial clock rates.
Table 7-3
Output Serial Clock Rates
Logic Type
Minimum Rate
Maximum Rate
LVDS
1 x (word size) kHz
400 MHz
Chapter 7
221
Digital Signal Interface Module
Clock Timing
Table 7-3
Output Serial Clock Rates
Logic Type
Minimum Rate
Maximum Rate
LVTTL and CMOS
1 x (word size) kHz
150 MHz
Table 7-4
Input Serial Clock Rates
Logic Type
Data Type
Minimum Rate
Maximum Rate
LVDS
Samples
1 x (word size) kHz
400
Pre-FIR
Samples
1 x (word size) kHz
the smaller of: 501 x (word size) MHz
or
400 MHz
N/A
1 x (word size) kHz
150 MHz
LVTTL and CMOS
1. The maximum sample rate depends on the selected filter when the data rate is Pre-FIR Samples. Refer to “Input Mode” on page
236 for more information.
Parallel and Parallel Interleaved Port Configuration Clock Rates
Parallel and parallel interleaved port configurations have other limiting factors for the clock and sample
rates:
•
logic type
•
Clocks per sample selection
•
IQ or IF digital signal type
Clocks per sample (clocks/sample) is the ratio of the clock to sample rate. For an IQ signal type, the sample
rate is reduced by the clocks per sample value when the value is greater than one. For an IF signal or an input
signal, clocks per sample is always set to one. Refer to Table 7-5 for the Output mode parallel and parallel
interleaved port configuration clock rates.
Table 7-5
Output Parallel and Parallel Interleaved Clock Rates
Logic Type
Signal Type
Minimum Rate
Maximum Rate
LVDS
IQ
1 x (clocks/sample) kHz
the smaller of: 100 x (clocks /sample) MHz
or
400 MHz
IF
4 kHz
400 MHz
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Clock Timing
Table 7-5
Output Parallel and Parallel Interleaved Clock Rates
Logic Type
Signal Type
Minimum Rate
Maximum Rate
Other
IQ
1 x (clocks/sample) kHz
the smaller of: 100 x (clocks /sample) MHz
or
150 MHz
IF
4 kHz
150 MHz
For Input mode, the maximum clock rate is limited by the following factors:
•
sample size
•
data type
•
selected filter for Pre-FIR Samples
Refer to Table 7-6 for the Input mode parallel and parallel interleaved port configuration clock rates.
Table 7-6
Input Parallel and Parallel Interleaved Clock Rates
Logic Type
Data Type
Minimum Rate
Maximum Rate
N/A
Samples
1 kHz
100 MHz
Pre-FIR Samples
1 kHz
501 MHz
1. The maximum sample rate depends on the selected filter when the data rate is Pre-FIR Samples. Refer to “Input Mode”
on page 236 for more information.
Clock Source
The clock signal for the N5102A module is provided in one of three ways through the following selections:
•
Internal: generated internally in the interface module (requires an external reference)
•
External: generated externally through the Ext Clock In connector
•
Device: generated externally through the Device Interface connector
The clock source is selected using the N5102A module UI on the signal generator, see Figure 7-2.
Chapter 7
223
Digital Signal Interface Module
Clock Timing
Figure 7-2
Clock Source Selection
External and Device selection:
Set to match the clock rate
of the applied clock signal
Internal selection: Set the
internal clock rate
Internal clock source
selection: Set the frequency
of the applied reference
signal.
When you select a clock source, you must let the N5102A module know the frequency of the clock signal
using the Clock Rate softkey. In the internal clock source mode, use this softkey to set the internal clock rate.
For device and external clock sources, this softkey must reflect the frequency of the applied clock signal.
When the clock source is Internal, a frequency reference must be applied to the Freq Ref connector. The
frequency of this applied signal needs to be specified using the Reference Frequency softkey, unless the
current setting matches that of the applied signal.
The selected clock source provides the interface module output clock signal at the Clock Out and the Device
Interface connectors.
Common Frequency Reference
The clocking flexibility of the digital signal interface module allows the setting of arbitrary clock rates for
the device under test. In general, the clock rate inside the ESG will be different from the interface module
clock rate, so the interface module performs a rate conversion. An important aspect of this conversion is to
have accurate clock rate information to avoid losing data. The module relies on relative clock accuracy,
instead of absolute accuracy, that must be ensured by using a single frequency reference for all clock rates
involved in the test setup. This can be implemented in various ways (see the five drawings in Figure 7-3 on
page 226), but whatever way it is implemented, the clock inside the signal generator must have the same
base frequency reference as the clock used by the device under test.
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Digital Signal Interface Module
Clock Timing
ESG Frequency Reference Connections
When a frequency reference is connected to the signal generator, it is applied to one of two rear panel
connectors:
•
10 MHz IN
•
BASEBAND GEN REF IN
The BASEBAND GEN REF IN connector will accept a frequency reference in the range of 1 to 100 MHz. If
the external or device under test clock source cannot provide or accept a frequency reference, that clock
signal can be applied to this connector and used as the frequency reference (as long as the frequencies are
within the specified range).
Whenever an external clock signal or frequency reference is connected to the BASEBAND GEN REF IN
connector, its frequency needs to be entered into the current signal generator modulation format. For
information on the BASEBAND GEN REF IN connector refer to Chapter 2, “E4438C Vector Signal
Generator Overview,” on page 19. For information on the associated softkeys and fields for entering the
frequency of the applied clock signal or frequency reference, refer to the Key and Data Field Reference.
Chapter 7
225
Digital Signal Interface Module
Clock Timing
Figure 7-3
Frequency Reference Setup Diagrams for the N5102A Module Clock Signal
Internally Generated Clock
Device (DUT) Supplied Clock
NOTE: Use only one of the two signal generator frequency reference inputs.
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Digital Signal Interface Module
Clock Timing
Externally Supplied Clock
NOTE: Use only one of the two signal generator frequency reference inputs.
Clock Timing for Parallel Data
Some components require multiple clocks during a single sample period. (A sample period consists of an I
and Q sample). For parallel data transmissions, you can select one, two, or four clocks per sample. For
clocks per sample greater than one, the I and Q samples are held constant to accommodate the additional
clock periods. This reduces the sample rate relative to the clock rate by a factor equal to the clocks per
sample selection. For example, when four is selected, the sample rate is reduced by a factor of four (sample
rate to clock rate ratio). Figure 7-4 demonstrates the clock timing for each clocks per sample selection. For
input mode, the clocks per sample setting is always one.
Chapter 7
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Digital Signal Interface Module
Clock Timing
Figure 7-4
Clock Sample Timing for Parallel Port Configuration
1 Clock Per Sample
1 Sample Period
1 Clock
Clock and sample rates are the same
Clock
I sample
4 bits per word
Q sample
4 bits per word
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Digital Signal Interface Module
Clock Timing
2 Clocks Per Sample
Sample rate decreases by a factor of two
1 Sample Period
2 Clocks
Clock
I sample
4 bits per word
Q sample
4 bits per word
4 Clocks Per Sample
Sample rate decreases by a factor of four
1 Sample Period
4 Clocks
Clock
I sample
4 bits per word
Q sample
4 bits per word
Chapter 7
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Digital Signal Interface Module
Clock Timing
Clock Timing for Parallel Interleaved Data
The N5102A module provides the capability to interleave the digital I and Q samples. There are two choices
for interleaving:
•
IQ, where the I sample is transmitted first
•
QI, where the Q sample is transmitted first
When parallel interleaved is selected, all samples are transmitted on the I data lines. This effectively
transmits the same number of samples during a sample period on half the number of data lines as compared
to non-interleaved samples. (A sample period consists of an I and Q sample.) Clocks per sample is still a
valid parameter for parallel interleaved transmissions and creates a reduction in the sample rate relative to
the clock rate. The clocks per sample selection is the ratio of the reduction. Figure 7-5 shows each of the
clocks per sample selections, for a parallel IQ interleaved port configuration, using a word sized of four bits
and the clock timing relative to the I and Q samples. For a parallel QI interleaved port configuration, just
reverse the I and Q sample positions. For input mode, the clocks per sample setting is always one.
Figure 7-5
Clock Timing for a Parallel IQ Interleaved Port Configuration
1 Clock Per Sample
The I sample is transmitted on one clock transition and the Q sample is transmitted on the
other transition; the sample and clock rates are the same.
1 Sample Period
1 Clock
Clock
I sample
4 bits per word
230
Q sample
4 bits per word
Chapter 7
Digital Signal Interface Module
Clock Timing
2 Clocks Per Sample
The I sample is transmitted for one clock period and the Q sample is transmitted during the second
clock period; the sample rate decreases by a factor of two.
1 Sample Period
2 Clocks
Clock
I sample
4 bits per word
Q sample
4 bits per word
4 Clocks Per Sample
The I sample is transmitted for the first two clock periods and the Q sample is transmitted during the second two
clock periods; the sample rate is decreased by a factor of four.
1 Sample Period
4 Clocks
Clock
I sample
4 bits per word
Chapter 7
Q sample
4 bits per word
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Digital Signal Interface Module
Clock Timing
Clock Timing for Serial Data
Figure 7-6 shows the clock timing for a serial port configuration. Notice that the serial transmission includes
frame pulses that mark the beginning of each sample where the clock delineates the beginning of each bit.
For serial transmission, the clock and the bit rates are the same, but the sample rate varies depending on the
number of bits per word that are entered using the Word Size softkey. The number of bits per word is the same
as the number of bits per sample.
Figure 7-6
Clock Timing for a Serial Port Configuration
1 Sample
Frame Marker
Clock
Data Bits
4 bits per word
Clock Timing for Phase and Skew Adjustments
The N5102A module provides phase and skew adjustments for the clock relative to the data and can be used
to align the clock with the valid portion of the data. The phase has a 90 degree resolution (0, 90, 180, and
270 degree selections) for clock rates from 10 to 200 MHz and a 180 degree resolution (0 and 180 degree
selections) for clock rates below 10 MHz and greater than 200 MHz.
The skew is displayed in nanoseconds with a maximum range of ±5 ns using a maximum of ±127 discrete
steps. Both the skew range and the number of discrete steps are variable with a dependency on the clock rate.
The skew range decreases as the clock rate is increased and increases as the clock rate is decreased. The
maximum skew range is reached at a clock rate of approximately 99 MHz and is maintained down to a clock
rate of 25 MHz. For clock rates below 25 MHz, the skew adjustment is unavailable.
A discrete step is calculated using the following formula:
1
----------------------------------------256 × Clock Rate
The number of discrete steps required to reach the maximum skew range decreases at lower frequencies. For
example, at a clock rate of 50 MHz, 127 steps would exceed the maximum skew range of ±5 ns, so the actual
number of discrete steps would be less than 127.
Figure 7-7 is an example of a phase and skew adjustment and shows the original clock and its phase position
relative to the data after each adjustment. Notice that the skew adjustment adds to the phase setting.
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Clock Timing
Figure 7-7
Clock Phase and Skew Adjustments
90 degree phase adjustment
Clock skew adjustment
Phase and
skew adjusted
clock
Phase adjusted
clock
Clock
Data
Chapter 7
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Digital Signal Interface Module
Connecting the Clock Source and the Device Under Test
Connecting the Clock Source and the Device Under Test
As shown in Figure 7-3 on page 226, there are numerous ways to provide a common frequency reference to
the system components (ESG, N5102A module, and the device under test). Figure 7-8 shows an example
setup where the signal generator supplies the common frequency reference and the N5102A module is
providing the clock to the device.
CAUTION
Figure 7-8
The Device Interface connector on the interface module communicates using high speed
digital data. Use ESD precautions to eliminate potential damage when making connections.
Example Setup using the ESG 10 MHz Frequency Reference
Signal generator 10 MHz Out
Common Freq Ref cable
Freq Ref connector
Device under test
Break-out board
Device interface connection
NOTE
234
User furnished ribbon cable(s) connect
between the device and break-out board.
The clock to the device is in the ribbon
cable.
You must disconnect the digital bus cable and the digital module while downloading
firmware to the ESG.
Chapter 7
Digital Signal Interface Module
Connecting the Clock Source and the Device Under Test
1. Refer to the five setup diagrams in Figure 7-3 on page 226 and connect the frequency reference cable
according to the clock source.
2. If an external clock source is used, connect the external clock signal to the Ext Clock In connector on the
interface module.
3. Select the break-out board that has the output connector suited for the application.
NOTE
If the Device Interface mating connector is used with the device under test, refer to Figure
7-8 for the device interface connection and connect the device to the N5102A module. Then
proceed to “Operating the N5102A Module in Output Mode” on page 238 or “Operating
the N5102A Module in Input Mode” on page 247.
4. Refer to Figure 7-8. Connect the break-out board to the Device Interface connector on the N5102A
module.
5. Connect the device to the break-out board.
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Data Types
Data Types
The following block diagram indicates where in the ESG signal generation process the data is injected for
input mode or tapped for output mode.
Output
Mode
Pre-FIR
Samples
Samples
ESG
LO
FIR
Data
Generator
I,Q
DACs
Filtering
Pre-FIR
Samples
RF
I/Q
Modulator
Samples
Input
Mode
Output Mode
When using an ARB format, the data type is always Samples and no filtering is applied to the data
samples.The samples are sent to the digital module at the ARB sample clock rate.
For real-time formats, choosing Samples as the data type will send filtered samples to the digital module at a
rate between 50 MHz and 100 MHz. Selecting Pre-FIR Samples, sends unfiltered samples to the digital
module at a rate equal to the sample rate of the current format.
Input Mode
When the data type is Samples, the data samples coming through the digital module are injected at a point
that bypasses the filtering process.
If Pre-FIR Samples is selected, the data samples are injected before the filtering process. The maximum rate
will be determined by the selected filter. Refer to Table 7-7.
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Data Types
Table 7-7
Maximum Sample Rate for Selected Filter
Filter
Gaussian
Nyquist
Root Nyquist
Rectangle
Edge
UN3/4 GSM Gaussian
IS-95
IS 95 w/EQ
Maximum Rate
50 MHz
IS-95 Mod
IS-95 Mod w/EQ
25 MHz
APCO 25 C4FM
12.5 MHz
The Filter softkey accesses a menu that enables you set the desired filtering parameters.
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Operating the N5102A Module in Output Mode
Operating the N5102A Module in Output Mode
This section shows how to set the parameters for the N5102A module using the signal generator UI in the
output direction. Each procedure contains a figure that shows the softkey menu structure for the interface
module function being performed.
Setting up the Signal Generator Baseband Data
The digital signal interface module receives data from a baseband source and outputs a digital IQ or digital
IF signal relative to the selected logic type. Because an ESG provides the baseband data, the first procedure
in operating the interface module is configuring the ESG using one of the real-time or ARB modulation
formats, or playing back a stored file using the Dual ARB player. For information on configuring the ESG,
refer to Chapter 4, “Basic Digital Operation (Option 001/601 or 002/602),” on page 89.
1. Preset the signal generator.
2. Select the modulation format (TDMA, Custom, and so forth) and set the desired parameters.
3. Turn-on the modulation format.
Accessing the N5102A Module User Interface
Press Aux Fctn > N5102A Interface.
This accesses the UI (first-level softkey menu shown in Figure 7-9) that is used to configure the digital
signal interface module. Notice the graphic, in the ESG display, showing a setup where the N5102A module
is generating its own internal clock signal. This graphic changes to reflect the current clock source selection.
Figure 7-9
First-Level Softkey Menu
Line is grayed out until the N5102A module interface is turned on
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Choosing the Logic Type and Port Configuration
Figure 7-10
Logic and Port Configuration Softkey Menus
1. Refer to Figure 7-10. Press the Logic Type softkey.
From this menu, choose a logic type.
CAUTION
Changing the logic type can increase or decrease the signal voltage level going to the device
under test. To avoid damaging the device and/or the N5102A module, ensure that both are
capable of handling the voltage change.
2. Select the logic type required for the device being tested.
A caution message is displayed whenever a change is made to the logic types, and a softkey selection
appears requesting confirmation.
3. Refer to Figure 7-10. Press the Port Config softkey.
In this menu, select either a serial, parallel, or parallel interleaved data transmission.
NOTE
Chapter 7
Within the data and clock setup softkey menus, some softkeys function relative to the
current configuration. Softkeys that are grayed out are not available for the current setup.
Refer to the help text to determine which parameter is causing the softkey to be unavailable.
Press the Help hardkey on the ESG front panel and then the softkey that is unavailable.
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4. Select the port configuration for the device.
Selecting the Output Direction
Press Data Setup > Direction Input Output to Output and press Return.
NOTE
If Option 003 is the only option installed, the direction softkey will be unavailable and the
mode will always be output. With both Option 003 (output mode) and Option 004 (input
mode) installed, the default direction is output.
Selecting the Data Parameters
This procedure guides you through the data setup menu. Softkeys that have self-explanatory names are
generally not mentioned. For example, the Word Size softkey. For more information on all of the softkeys,
refer to Key and Data Field Reference.
1. Refer to Figure 7-11. Press the Data Setup softkey.
Figure 7-11
Data Setup Menu Location
Accesses the data setup menu
This softkey menu accesses the various parameters that govern the data received by the device under
test. The status area of the display shows the number of data lines used for both I and Q along with the
clock position relative to the data. When the port configuration is parallel or parallel interleaved, the
number of data lines indicated is equivalent to the word (sample) size. When the port configuration is
serial, the display will show that only one I and one Q data line is being used along with the frame
marker that delineates the beginning of a sample. Figure 7-12 shows the data setup menu structure.
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Figure 7-12
Data Setup Softkey Menu with Parallel Port Configuration
Inactive for ARB formats
Inactive for word
size = 16 bits
Inactive for a serial port
configuration
Frame polarity is active
for a serial port configuration
Available only while in
output mode
2. If a real-time modulation format is being used, press the Data Type softkey. (This softkey is inactive
when an ARB modulation format is turned on.)
In this menu, select whether the real-time baseband data from the signal generator is either filtered
(Samples) or unfiltered (Pre-FIR Samples). The selection is dependent on the test needs. The Samples
selection provides FIR filtered baseband samples according to the communication standard of the active
modulation format. This is the preset selection and the one most commonly used. However if the device
being tested already incorporates FIR filters, the Pre-FIR Samples selection should be used to avoid
double filtering.
3. Select the data type that is appropriate for the test.
4. Press the Numeric Format softkey.
From this menu, select how the binary values are represented. Selecting 2’s complement allows both
positive and negative data values. Use the Offset Binary selection when components cannot process
negative values.
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5. Select the numeric format required for the test.
6. Press the More (1 of 2) softkey.
From this softkey menu, select the bit order, swap I and Q, select the polarity of the transmitted data, and
access menus that provide data negation, scaling, gain, offset, and IQ rotation adjustments.
7. Press the Data Negation softkey.
Negation differs from changing the I and Q polarity. Applied to a sample, negation changes the affected
sample by expressing it in the two's complement form, multiplying it by negative one, and converting the
sample back to the selected numeric format. This can be done for I samples, Q samples, or both.
The choice to use negation is dependent on the device being tested and how it needs to receive the data.
8. Press the Gain, Offset & Scaling softkey.
Use the softkeys in this menu for the following functions:
•
reduce sample values for both I and Q using the Scaling softkey
•
increase or decrease the sample values independently for I and Q using the I Gain and Q Gain
softkeys
•
compensate for or add a DC offset using the I Offset and Q Offset softkeys
•
rotate the data on the IQ plane using the Rotation softkey
9. Make any required scaling, gain, offset, or rotation adjustments to properly test the device.
10. Press Return > Return to return to the first-level softkey menu.
Configuring the Clock Signal
1. Refer to Figure 7-13. Press the Clock Setup softkey.
Figure 7-13
Clock Setup Menu Location
Accesses the Clock Setup Menu
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From this softkey menu, set all of the clock parameters that synchronize the clocks between the N5102A
module and the ESG. You can also change the clock signal phase so the clock occurs during the valid
portion of the data. Figure 7-14 shows the clock setup menu.
Figure 7-14
Clock Setup Softkey Menu for a Parallel Port Configuration
Inactive for a serial port configuration and the IF signal type
Inactive for clock rates below 25 MHz
Active for only the Internal clock source selection
Inactive for clock rates below
10 MHz and above 200 MHz
The top graphic on the display shows the current clock source that provides the output clock signal at the
Clock Out and Device Interface connectors. The graphic changes to reflect the clock source selection
discussed later in this procedure. The bottom graphic shows the clock position relative to the data. The
displayed clock signal will change to reflect the following:
•
clocks per sample selection
•
clock phase choice
•
clock skew adjustment
•
clock polarity selection
If the device or external clock does not match the frequency, one of the following error messages will
appear on the ESG:
805
Chapter 7
Digital module output FIFO overflow error; There are more samples being produced than can be
consumed at the current clock rate. Verify that the digital module clock is set up properly.
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This error is reported when the output FIFO is overflowing in
the digital module. This error can be generated if an external clock
or its reference is not set up properly, or if the internal VCO is
unlocked.
806
Digital module output FIFO underflow error; There are not enough samples being produced for the
current clock rate. Verify that the digital module clock is set up properly.
This error is reported when the output FIFO is underflowing in the digital module.
This error can be generated if an external clock or its reference is not set up properly,
or if the internal VCO is unlocked.
2. If the port configuration is parallel or parallel interleaved, using an IQ signal type, press the
Clocks Per Sample softkey.
Notice that multiple clocks per sample can be selected. Some DACs require the ability to clock multiple
times for each sample; having a clocks per sample value greater than one reduces the sample rate by a
factor equal to the selected number of clocks per sample. The sample rate is viewed on the first-level and
Data Setup softkey menus.
3. Select the clocks per sample value to fit the test.
4. Press the Clock Source softkey.
From this menu, select the clock signal source. With each selection, the clock routing display in the
signal generator clock setup menu will change to reflect the current clock source. This will be indicated
by a change in the graphic.
5. Select the clock source.
If External or Device is Selected
Press the Clock Rate softkey and enter the clock rate of the externally applied clock signal.
NOTE
The clock phase and clock skew may need to be adjusted any time the clock rate setting is
changed. Refer to “Clock Timing for Phase and Skew Adjustments” on page 232.
For the External selection, the signal is supplied by an external clock source and applied to the Ext Clock
In connector. For the Device selection, the clock signal is supplied through the Device Interface
connector, generally by the device under test.
If Internal is Selected
Using an external frequency reference, the N5102A module generates its own internal clock signal. The
reference frequency signal must be applied to the Freq Ref connector on the digital module.
a. Press the Reference Frequency softkey and enter the frequency of the externally applied frequency
reference.
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b. Press the Clock Rate softkey and enter the appropriate clock rate.
Table 7-8 provides a quick view of the settings and connections associated with each clock source
selection.
Table 7-8
Clock Source Settings and Connectors
Clock Source
Softkeys
Reference
Frequency
N5102A Module Connection
Clock Rate1
External
•
Device
•
Internal2
•
•
Freq Ref Ext Clock In Device Interface
•
•
•
1. For the Internal selection, this sets the internal clock rate. For the External and Device selections, this
tells the interface module the rate of the applied clock signal.
2. There should be no clock signal applied to the Ext Clock In connector.
6. Press the Clock Phase softkey.
From the menu that appears, you can adjust the phase of the clock relative to the data in 90 degree
increments. The selections provide a coarse adjustment for positioning the clock on the valid portion of
the data. Selecting 180 degrees is the same as selecting a negative clock polarity.
The 90 degree and 270 degree selections are not available when the clock rate is set below 10 MHz or
above 200 MHz. If 90 degrees or 270 degrees is selected when the clock rate is set below 10 MHz or
above 200 MHz, the phase will change to 0 degrees or 180 degrees, respectively.
NOTE
The clock phase and clock skew may need to be adjusted any time the clock rate setting is
changed. Refer to “Clock Timing for Phase and Skew Adjustments” on page 232.
7. Enter the required phase adjustment.
8. Press the Return softkey to return to the clock setup menu.
9. Press the Clock Skew softkey.
This provides a fine adjustment for the clock relative to its current phase position. The skew is a phase
adjustment using increments of time. This enables greater skew adjustment capability at higher clock
rates. For clock rates below 25 MHz, this softkey is inactive.
The skew has discrete values with a range that is dependent on the clock rate. Refer to “Clock Timing for
Phase and Skew Adjustments” on page 232 for more information on skew settings.
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10. Enter the skew adjustment that best positions the clock with the valid portion of the data.
11. Press the Clock Polarity Neg Pos softkey to Neg.
This shifts the clock signal 180 degrees, so that the data starts during the negative clock transition. This
has the same affect as selecting the 180 degree phase adjustment.
12. Make the clock polarity selection that is required for the device being tested.
13. Press the Return hardkey to return to the first-level softkey menu.
The clock source selection is also reflected in the first-level softkey menu graphic. For example, if the
device is the new clock source, the graphic will show that the frequency reference is now connected to
the DUT and the DUT has an input clock line going to the N5102A module.
Generating Digital Data
Press the N5102A Off On softkey to On.
Digital data is now being transferred through the N5102A module to the device. The green status light
should be blinking. This indicates that the data lines are active. If the status light is solidly illuminated (not
blinking), all the data lines are inactive. The status light comes on and stays on (blinking or solid) after the
first time the N5102A module is turned on (N5102A Off On to On). The status light will stay on until the
module is disconnected from its power supply.
The interface module can only be turned on while a modulation format is active. If the modulation format is
turned off while the module is on, the module will turn off and an error will be reported.
NOTE
246
If changes are made to the baseband data parameters, it is recommended that you first
disable the digital output (N5102A Off On softkey to Off) to avoid exposing your device and
the N5102A module to the signal variations that may occur during the parameter changes.
Chapter 7
Digital Signal Interface Module
Operating the N5102A Module in Input Mode
Operating the N5102A Module in Input Mode
This section shows how to set the parameters for the N5102A module using the signal generator UI in the
input direction. Each procedure contains a figure that shows the softkey menu structure for the interface
module function being performed.
Refer to “Connecting the Clock Source and the Device Under Test” on page 234 and configure the test
setup.
Accessing the N5102A Module User Interface
All parameters for the N5102A module are set with softkeys on the ESG signal generator.
Press Aux Fctn > N5102A Interface.
This accesses the UI (first-level softkey menu shown in Figure 7-15) that is used to configure the digital
signal interface module. Notice the graphic, in the ESG display, showing a setup where the N5102A module
is generating its own internal clock signal. This graphic changes to reflect the current clock source selection.
Figure 7-15
First-Level Softkey Menu
Internal clock going to the DUT
Line is grayed out until the N5102A module interface is turned on
Chapter 7
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Selecting the Input Direction
If both Option 003 (output mode) and Option 004 (input mode) are installed, you must select the input
direction.
Press Data Setup > Direction Input Output to Input and press Return.
NOTE
If only Option 004 is installed, the direction softkey will be unavailable and the mode will
always be input.
Choosing the Logic Type and Port Configuration
Figure 7-16
Logic and Port Configuration Softkey Menus
1. Refer to Figure 7-16. Press the Logic Type softkey.
From this menu, choose a logic type.
CAUTION
248
Changing the logic type can increase or decrease the signal voltage level. To avoid
damaging the device and/or the N5102A module, ensure that both are capable of handling
the voltage change.
Chapter 7
Digital Signal Interface Module
Operating the N5102A Module in Input Mode
2. Select the logic type required for the device being tested.
A caution message is displayed whenever a change is made to the logic types, and a softkey selection
appears asking for confirmation.
3. Refer to Figure 7-16. Press the Port Config softkey.
In this menu, select either a serial, parallel, or parallel interleaved data transmission.
NOTE
Within the data and clock setup softkey menus, some softkeys function relative to the
current configuration. Softkeys that are grayed out are not available for the current setup.
Refer to the help text to determine which parameter is causing the softkey to be unavailable.
Press the Help hardkey on the ESG front panel and then the softkey that is unavailable.
4. Select the port configuration for the device being tested.
Configuring the Clock Signal
1. Refer to Figure 7-17. Press the Clock Setup softkey.
Figure 7-17
Clock Setup Menu Location
Accesses the Clock Setup Menu
From this softkey menu, set all of the clock parameters that synchronize the data between the N5102A
module and the device. From this menu, the clock signal phase can be changed so the clock occurs
during the valid portion of the data. Figure 7-18 shows the clock setup menu.
If the device or external clock does not match the frequency, one of the following error messages will
appear on the ESG:
803
Chapter 7
Digital module input FIFO overflow error; There are more samples being produced than can be
consumed at the current clock rate. Verify that the digital module clock is set up properly.
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This error is reported when the digital module clock setup is not
synchronized with the rate the samples are entering the digital
module. Verify that the input clock rate matches the specified
clock rate under the clock setup menu.
804
Digital module input FIFO underflow error; There are not enough samples being produced for the current
clock rate. Verify that the digital module clock is set up properly.
This error is reported when the digital module clock setup is not
synchronized with the rate the samples are entering the digital
module. Verify that the input clock rate matches the specified
clock rate under the clock setup menu.
Figure 7-18
Clock Setup Softkey Menu for a Parallel Port Configuration
Inactive for Input mode
Inactive for clock rates below 25 MHz
Active for only the Internal clock source selection
Inactive for clock rates below
10 MHz and above 200 MHz
The top graphic on the display shows the current clock source that provides the output clock signal at the
Clock Out and Device Interface connectors. The graphic changes to reflect the clock source selection
discussed later in this procedure. The bottom graphic shows the clock edges relative to the data. The
displayed clock signal will change to reflect the following:
•
250
clock phase choice
Chapter 7
Digital Signal Interface Module
Operating the N5102A Module in Input Mode
•
clock skew adjustment
•
clock polarity selection
2. Press the Clock Source softkey.
From this menu, select the clock signal source. With each selection, the clock routing display in the
signal generator clock setup menu will change to reflect the current clock source. This will be indicated
by a change in the graphic.
3. Select the clock source.
If External or Device is Selected
Press the Clock Rate softkey and enter the clock rate of the externally applied clock signal.
NOTE
The clock phase and clock skew may need to be adjusted any time the clock rate setting is
changed. Refer to “Clock Timing for Phase and Skew Adjustments” on page 232.
For the External selection, the signal is supplied by an external clock source and applied to the Ext Clock
In connector. For the Device selection, the clock signal is supplied through the Device Interface
connector, generally by the device being tested.
If Internal is Selected
Using an external frequency reference, the N5102A module generates its own internal clock signal. The
reference frequency signal must be applied to the Freq Ref connector on the digital module.
a. Press the Reference Frequency softkey and enter the frequency of the externally applied frequency
reference.
b. Press the Clock Rate softkey and enter the appropriate clock rate.
Table 7-9 provides a quick view of the settings and connections associated with each clock source
selection.
Chapter 7
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Operating the N5102A Module in Input Mode
Table 7-9
Clock Source Settings and Connectors
Clock Source
Softkeys
Reference
Frequency
N5102A Module Connection
Clock Rate1
External
•
Device
•
Internal2
•
•
Freq Ref Ext Clock In Device Interface
•
•
•
1. For the Internal selection, this sets the internal clock rate. For the External and Device selections, this
tells the interface module the rate of the applied clock signal.
2. There should be no clock signal applied to the Ext Clock In connector when Internal is being used.
4. Press the Clock Phase softkey.
From the menu that appears, the phase of the clock relative to the data can be changed in 90 degree
increments. The selections provide a coarse adjustment for positioning the clock on the valid portion of
the data. Selecting 180 degrees is the same as selecting a negative clock polarity.
The 90 degree and 270 degree selections are not available when the clock rate is set below 10 MHz or
above 200 MHz. If 90 degrees or 270 degrees is selected when the clock rate is set below 10 MHz or
above 200 MHz, the phase will change to 0 degrees or 180 degrees, respectively.
NOTE
The clock phase and clock skew may need to be adjusted any time the clock rate setting is
changed. Refer to “Clock Timing for Phase and Skew Adjustments” on page 232.
5. Enter the required phase adjustment.
6. Press the Return softkey to return to the clock setup menu.
7. Press the Clock Skew softkey.
This provides a fine adjustment for the clock relative to its current phase position. The skew is a phase
adjustment using increments of time. This enables greater skew adjustment capability at higher clock
rates. For clock rates below 25 MHz, this softkey is inactive.
The skew has discrete values with a range that is dependent on the clock rate. Refer to “Clock Timing for
Phase and Skew Adjustments” on page 232 for more information on skew settings.
8. Enter the skew adjustment that best positions the clock with the valid portion of the data.
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9. Press the Clock Polarity Neg Pos softkey to Neg.
This shifts the clock signal 180 degrees, so that the data starts during the negative clock transition. This
has the same affect as selecting the 180 degree phase adjustment.
10. Make the clock polarity selection that is required for the device being tested.
11. Press the Return hardkey to return to the first-level softkey menu.
The clock source selection is also reflected in the first-level softkey menu graphic. For example, if the
device is the new clock source, you will see that the frequency reference is now connected to the DUT
and the DUT has an input clock line going to the N5102A module.
Selecting the Data Parameters
This procedure guides you through the data setup menu. Softkeys that have self-explanatory names are
generally not mentioned. For example, the Word Size softkey. For more information on all of the softkeys,
refer to the Key and Data Field Reference.
1. Refer to Figure 7-19. Press the Data Setup softkey.
Figure 7-19
Data Setup Menu Location
Accesses the data setup menu
This softkey menu accesses the various parameters that govern the data received by the ESG The status
area of the display shows the number of data lines used for both I and Q along with the clock position
relative to the data. Figure 7-20 shows the data setup menu structure.
Chapter 7
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Figure 7-20
Data Setup Softkey Menu with Parallel Port Configuration
Inactive for a serial port
configuration
Frame polarity is active
for a serial port configuration
Only available when the
N5102A digital module is
turned on and using input mode
Only available when
data type is
Pre-FIR Samples
2. Press the Data Type softkey.
In this menu, select the data type to be either filtered (Samples) or unfiltered (Pre-FIR Samples). The
selection is dependent on the test needs and the device under test. However if the device being tested
already incorporates FIR filters, the Pre-FIR Samples selection should be used to avoid double filtering.
Refer to “Data Types” on page 236, for more information.
3. Select the data type that is appropriate for the test needs.
4. Press the Numeric Format softkey.
From this menu, select how the binary values are represented. Selecting 2’s complement allows both
positive and negative data values. Use the Offset Binary selection when components cannot process
negative values.
5. Select the numeric format required for the test.
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6. Press the More (1 of 2) softkey.
From this softkey menu, select the bit order, swap I and Q, the polarity of the data, and access menus that
provides data negation, scaling, and filtering parameters.
7. Press the Data Negation softkey.
Negation differs from changing the I and Q polarity. Applied to a sample, negation changes the affected
sample by expressing it in the two's complement form, multiplying it by negative one, and converting the
sample back to the selected numeric format. This can be done for I samples, Q samples, or both.
The choice to use negation is dependent on the device being tested.
8. To access I/Q scaling and filter parameters, press Return > N5102A Off On to On. This will invoke the
real time Custom format in the ESG baseband generator. This is needed to set the filter parameters when
Pre-FIR Samples is selected as the data type.
9. Press the Baseband Setup softkey.
Use this softkey menu to adjust the I/Q scaling and access filter parameters. If the selected data type is
Samples, the Filter softkey is grayed out (inactive). For more information on user-defined filtering, refer
to the “Using Finite Impulse Response (FIR) Filters” on page 168 and “Modifying a FIR Filter Using
the FIR Table Editor” on page 173.
Digital Data
If the N5102A digital module is not on, press Return > Return > N5102A Off On to On.
Digital data is now being transferred through the N5102A module to the ESG. The green status light should
be blinking. This indicates that the data lines are active. If the status light is solidly illuminated (not
blinking), all the data lines are inactive. The status light comes on and stays on (blinking or solid) after the
first time the N5102A module is turned on (N5102A Off On to On). The status light will stay on until the
module is disconnected from its power supply.
NOTE
Chapter 7
If changes are made to the baseband data parameters, it is recommended that you first
disable the digital output (N5102A Off On softkey to Off) to avoid exposing the device and
the N5102A module to the signal variations that may occur during the parameter changes.
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8
Bluetooth Signals (Option 406)
Option 406 is only available for E4438C ESG Vector Signal Generators with Option 001/601or 002/602.
NOTE
This option is no longer available. Instead, order Signal Studio software, N7606B, to
generate Bluetooth waveforms that can be downloaded to the ESG.
The following list shows the topics covered in this chapter:
•
“Accessing the Bluetooth Setup Menu on the ESG” on page 258
•
“Setting Up Packet Parameters” on page 259
•
“Setting up Impairments” on page 261
•
“Using Burst” on page 263
•
“Using Clock/Gate Delay” on page 264
•
“Turning On a Bluetooth Signal” on page 265
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Accessing the Bluetooth Setup Menu on the ESG
Accessing the Bluetooth Setup Menu on the ESG
Option 406 is required to perform the following procedure.
This chapter will show you how to set up a sample Bluetooth packet with impairments that include additive
white gaussian noise (AWGN) using the front panel keys of the ESG. The procedures in this chapter build on
each other and are designed to be used sequentially.
1. Press Preset, then press Mode > More (1 of 2) > Wireless Networking > Bluetooth.
NOTE
For this section, the frequency and amplitude are set to typical Bluetooth values.
2. Press Frequency > 2.402 > GHz > Amplitude > 10 > dBm > Mode Setup.
The following figure shows a display of the Bluetooth menu.
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Setting Up Packet Parameters
Setting Up Packet Parameters
The steps in this procedure build upon the previous procedure.
The signal generator uses a DH1 (Data-High rate) packet for the Bluetooth format. The DH1 packet is a
single bundle of information transmitted within a piconet and covers a single timeslot. This packet consists
of 3 entities: the access code, the header, and the payload.
In the following example you will set the parameters of the DH1 packet.
1. Press Packet (DH1).
This accesses a menu that enables you to set the packet parameters.
The following figure displays the packet menu.
2. Press BD_ADDR > 000000 00 1000 > Enter.
This modifies the hexadecimal Bluetooth device address. Each Bluetooth transceiver is allocated a
unique 48-bit Bluetooth device address. This address is derived from the IEEE802 standard.
For addresses with alpha characters, use the softkeys along with the keypad for data entry.
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Setting Up Packet Parameters
3. Press AM_ADDR > 4 > Enter.
This sets the active member address and is used to distinguish between the active members participating
on the piconet.
NOTE
The all-zero AM_ADDR is reserved for broadcast messages.
4. Press Payload Data > 8 Bit Pattern > 10101010 > Enter.
This selects a repeating 8-bit pattern as the payload data.
The following figure now displays the new packet parameters.
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Setting up Impairments
Setting up Impairments
The steps in this procedure build upon the previous procedure. This procedure teaches you how to set up the
parameters for the impairment function.
1. Press Return > Return > Impairments.
This accesses a menu which enables you to set up impairments.
2. Press Freq Offset > 25 > kHz.
3. Press Freq Drift Type Linear Sine.
This sets the frequency drift type to linear. Linear frequency drift will occur across a period of time equal
to the duration of one fully loaded DH1 packet, regardless of the packet length. The default setting is the
sine drift deviation which is plus or minus from the carrier center frequency.
4. Press Drift Deviation > 25 > kHz.
This sets the maximum deviation of the frequency drift of the carrier frequency.
5. Press Mod Index > .325 > Enter.
Modulation index is defined as the ratio of peak-to-peak frequency deviation to the bit rate. When
modifying the Mod Index parameter, the peak-to-peak frequency deviation only is changed.
6. Press Symbol Timing Err > 1 > ppm.
This sets the symbol timing error in parts per million.
7. Press AWGN.
This accesses a menu from which you can select the parameters of the additive white Gaussian noise
(AWGN) to be applied as an impairment to the Bluetooth signal. The following parameters may be
changed while AWGN is off, but will not be applied unless AWGN and Impairments are both turned on.
a. Press C/N [1MHz] > 20 > dB.
This sets the carrier-to-noise ratio for a 1 MHz bandwidth.
b. Press Noise Seed > 2 > Enter.
This sets the noise seed value used to assign a specific sequence of noise to be added to the basic
Bluetooth signal. The noise seed is used to initialize the 16-bit shift register used for noise
generation. Different noise seeds generate different combinations of noise.
c. Press AWGN Off On to On.
This turns the AWGN, as a Bluetooth impairment, on.
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Setting up Impairments
8. Press Return > Impairments Off On to On.
This returns you to the Impairments menu and turns the impairments function on.
The following figure displays the impairment parameters.
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Using Burst
Using Burst
The steps in this procedure build upon the previous procedure.
1. Press Return to return to the top-level Bluetooth menu.
2. Notice that Burst Off On is set to On.
When burst is on, the signal power ramps up prior to transmitting the packet and then ramps down at the end
of the packet transmission. When burst is off, the transmitted packets link in a series with no power ramping.
The default burst setting is on, but for troubleshooting you may want to turn bursting off.
For this example burst is left in the on position.
Setting the Burst Power Ramp
This procedure builds upon the previous procedure.
Press Burst Power Ramp > 4 > Symbols.
This sets the duration of the power ramp to 4 symbols prior to transmitting the first symbol of the packet.
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Bluetooth Signals (Option 406)
Using Clock/Gate Delay
Using Clock/Gate Delay
The steps in this procedure build upon the previous procedure.
This function is available only when the payload data is continuous PN9 and is intended to be used during
bit error rate (BER) testing.
1. Press Packet (DH1) > Payload Data > Continuous PN9 > Return.
This activates the configuration that generates clock and gate signals relative to the Bluetooth signal.
2. Press Clock/Gate Delay > 4 > Symbols.
The clock and gate will be delayed 4 symbols to synchronize with the demodulated data signal from the
device under test (DUT) at the input of the BER analyzer.
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Turning On a Bluetooth Signal
Turning On a Bluetooth Signal
This procedure builds upon the previous procedure.
Press Bluetooth Off On to On.
This turns the operating state of the Bluetooth signal generator on.
The front panel I/Q and BLUETTH annunciators appear, and the signal builds.
The following figure displays the Bluetooth signal parameters.
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Turning On a Bluetooth Signal
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BERT (Options UN7 and 300)
This feature is available only in E4438C ESG Vector Signal Generators with Option 001/601or 002/602. The
following list shows the topics covered in this chapter:
•
“Setting Up a PHS Bit Error Rate Test (BERT)” on page 268
•
“Measuring RF Loopback BERT with Option 300” on page 273
•
“Using the External Frame Trigger Function with the EDGE Format” on page 288
•
“Bit Error Rate Tester–Option UN7” on page 292
•
“RF Loopback BER–Option 300” on page 303
•
“Verifying BERT Operation” on page 306
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Setting Up a PHS Bit Error Rate Test (BERT)
Setting Up a PHS Bit Error Rate Test (BERT)
This section shows how to make BERT measurements on a personal handyphone system (PHS) radio using
the ESG Signal Generator with Option UN7.
The following procedures explain how to set up the ESG for making BERT measurements:
•
“Connecting the Test Equipment” on page 269
•
“Setting the Carrier Frequency and Power Level” on page 270
•
“Selecting the Radio Data Format” on page 270
•
“Setting the Radio to a Receiver Mode” on page 271
•
“Selecting the BERT Data Pattern and Total Bits” on page 271
•
“Selecting the BERT Trigger” on page 271
•
“Starting BERT measurements” on page 272
Required Equipment
The following equipment is required to make BERT measurements.
•
ESG Signal Generator, model E4438C with Options 001/601or 002/602, 402, and UN7
•
an external controller to control the radio under test
•
an interface level matching circuit for interfacing between the radio under test and the signal generator
when the radio signal specifications are different from those of the signal generator
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Setting Up a PHS Bit Error Rate Test (BERT)
Connecting the Test Equipment
Refer to Figure 9-1.
1. Connect the cables between your radio and the ESG as follows:
Figure 9-1
Chapter 9
Setup for a PHS Bit Error Rate Test
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Setting Up a PHS Bit Error Rate Test (BERT)
Setting the Carrier Frequency and Power Level
1. Press the Preset hardkey.
2. Press the Frequency hardkey. Using the numeric keypad, set the signal generator RF output carrier
frequency to 1.89515 GHz.
3. Press the Amplitude hardkey. Using the numeric keypad, set the signal generator RF output amplitude to
−100 dBm.
The amplitude can also be set using an Amplitude softkey, located in the Baseband BERT softkey menu, that
is accessed by pressing the Aux Fctn > BERT > Baseband BERT softkeys.
Selecting the Radio Data Format
1. Press Mode > Real Time TDMA > PHS
This selects the PHS communications standard.
2. Toggle the Data Format Pattern Framed softkey to Framed.
When you select Framed for bursting the frame envelope, you will be transmitting framed data. This
means that you will be bursting the timeslots that you have activated and there will be no RF carrier
during the off timeslots.
Notice that the Configure Timeslots softkey has become an active softkey.
Observe the display and notice that the normal preset condition for downlink timeslot #1 has the timeslot
turned on and configured as a traffic channel (TCH).
3. Press Configure Timeslots.
The Timeslot # softkey shows that downlink timeslot #1 is selected as the active timeslot. The
Timeslot Off On softkey shows that downlink timeslot #1 is turned on. The Timeslot Type softkey shows that
downlink timeslot #1 is configured as a traffic channel.
4. Press Configure TCH.
The TCH softkey shows that PN9 is selected as a data pattern.
5. Press Return > Return > PHS Off On.
At this time the internal baseband generator will generate the internal data patterns that you have
configured for Downlink timeslot 1 and Uplink timeslot 1. A message is displayed while this process is
taking place. Notice, also, that the PHS, I/Q, and ENVLP display annunciators are turned on.
6. Press RF On/Off to toggle RF on.
Notice that the display annunciator changes from RF OFF to RF ON. The modulated signal is now
available at the RF OUTPUT connector.
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Setting the Radio to a Receiver Mode
Set the PHS radio to receive the signal of the specified carrier frequency and the timeslot 1, and output the
data used for the bit error rate measurements.
Selecting the BERT Data Pattern and Total Bits
1. Access the BERT function.
For an ESG with Option UN7 Installed
Press Aux Fctn > BERT > Configure BERT.
For an ESG with Options UN7 and 300 Installed
Press Aux Fctn > BERT > Baseband BERT > Configure BERT.
If the Data softkey does not show that PN9 is the selected data pattern, press
Data > PN9.
The selected PN sequence must match the data PN sequence used on the channel being measured. For
example if the DCH (DTCH) is using PN9 data, then the data selection in the BERT function must also
be PN9.
2. Press Total Bits > 100000 > Bits.
Selecting the BERT Trigger
1. Press Return > Configure Trigger.
If the BERT Trigger softkey does not show Trigger Key as the selected trigger, press
BERT Trigger > Trigger Key.
2. Press Return > BERT Off On.
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Starting BERT measurements
Press the front panel Trigger hardkey to start the BERT measurement. You will see the measurement result
values of the Total Bits, Error Bits, and BERT on the signal generator display.
NOTE
272
If you encounter problems making a BERT measurement, check the following:
•
Make sure that the cable connections are properly configured.
•
Make sure that the data pattern for the BERT measurement, specified by the Data
softkey, matches the data pattern in the traffic channel (TCH) for the RF signal being
input to the radio under test.
•
Make sure that the RF is turned on.
•
Make sure that the amplitude is set to the correct level.
•
Make sure that the radio under test is controlled to receive the signal of the specified
carrier frequency and the timeslot.
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BERT (Options UN7 and 300)
Measuring RF Loopback BERT with Option 300
Measuring RF Loopback BERT with Option 300
The following procedure uses the data looped back from the base transceiver station (BTS) to measure the
bit error ratio introduced by the BTS receiver when it is receiving coded data from the test equipment.
Timing synchronization must first be achieved between the BTS and the test equipment so that data can be
transmitted and received at the expected times. Synchronization is achievable either to a received broadcast
channel (BCH), to a received full rate speech traffic channel (TCH) in the GSM format, or a packet data
channel (PDCH) in the EDGE format.
Required Equipment
The following equipment is required to make loopback BERT measurements.
•
VSA Series Transmitter Tester, model E4406A, with the following required options:
− Option BAH - GSM Measurement Personality
NOTE
Option 202 replaces Option BAH in the VSA if EDGE support is required.
− Option 300 − 321.4 MHz IF Output
•
ESG Vector Signal Generator, model E4438C
− Option 300 − GSM/EDGE base station loopback BERT test capability (requires Options UN7,
001/601or 002/602, 402)
Connecting the Test Equipment
Refer to Figure 9-2 for connections to the ESG, VSA, and base station.
CAUTION
If the base station output power is to be greater than the VSA input power specification
(+30 dBm), an external attenuator needs to be inserted prior to the RF INPUT connector on
the VSA.
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Figure 9-2
NOTE
BTS Loopback Test Equipment Setup
This example uses an ARFCN of 124 for the BCH and synchronizes to the TCH midamble
in timeslot 2 on ARFCN 124. You can substitute as appropriate for your BTS.
All key presses assume factory defined defaults at preset.
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Configuring GSM Mode on the Agilent Technologies E4406A VSA Series Transmitter Tester
The following steps will show you how to set up the vector signal analyzer (VSA) for synchronization.
1. To preset the VSA:
Press Preset.
2. To select GSM mode:
Press MODE > GSM.
3. To set up GSM mode for BTS test:
Press Mode Setup > Radio > Band > P-GSM > Return.
Toggle Device BTS MS until BTS is underlined.
Toggle Freq Hopping On Off until Off is underlined.
4. To set the frequency:
Press FREQUENCY Channel > ARFCN 124.
Center Freq will show 959.800 MHz.
Select Burst Type > Normal.
Toggle TSC (Std) until Auto is underlined.
5. To lock the VSA and ESG to the BTS 13 MHz reference:
Press System > Reference > Freq Ref > 13 > MHz.
Toggle Freq Ref Int Ext until Ext is underlined.
Toggle 10 MHz Out Off On until On is underlined.
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Configuring GSM Mode on the ESG Vector Signal Generator
The following steps will show you how to configure a timeslot with multiframe data, set up traffic channel 1,
and set the frequency and amplitude in GSM mode on the signal generator.
When configuring a timeslot in this procedure, keep the following points in mind:
•
Prior to synchronization, the transmitter must be configured to generate multiframe data in the timeslot
to be tested.
•
TCH synchronization requires that the training sequences match between the ESG timeslot configuration
and the timeslot sent by the base station. The default for the ESG, which is TSC0, can be modified.
1. Press Preset.
2. Press Aux Fctn > BERT > BTS BERT GSM Loopback > Configure Measurement >
Transmit Settings.
3. Press GSM On Off to On > Data Format Pattern Framed to Framed > Configure Timeslots.
Refer to Figure 9-3. The GSM timeslot pattern is displayed on the screen.
Figure 9-3
4. Press Timeslot Off On to Off.
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5. Press Timeslot # > 2 > Enter.
Press Timeslot Type > Normal.
Press Configure Normal > E > Multiframe Channel > TCH/FS > PN9 or PN15.
NOTE
If the default training sequence (TSCO) does not match the training sequence sent by the
BTS, press Return > Return > TS and select the proper training sequence.
6. Press Return > Return > Return > Timeslot Off On to On.
7. Press Timeslot # > 1 > Enter.
Press Timeslot Type > Normal > Configure Normal > E > Multiframe Channel > TCH/FS > PN9 (or PN15).
Press Return > Return > Return > Timeslot Ampl Main Delta to Delta > Timeslot Off On to On.
Repeat these steps for timeslot 3.
8. Press Amplitude > More (1 of 2) > Alternate Amplitude > Alt Ampl Delta > 50 > dB.
9. To set up traffic channel 124 in GSM mode:
Press Frequency > More (1 of 2) > Freq Channels.
Press Device (BTS MS) to MS > Channel Band > GSM/EDGE Bands > P-GSM Mobile.
Press Freq Channels Off On to On.
Press Channel Number > 124 > Enter.
Refer to Figure 9-4. The active entry area displays the following:
Channel: 124 (914.80000000MHz)
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Figure 9-4
10. Press Amplitude > −95 > dBm.
The amplitude can also be set using an Amplitude softkey, located in the Baseband BERT softkey menu, that
is accessed by pressing the Aux Fctn > BERT > Baseband BERT softkeys.
11. Press Mode Setup > RF On/Off.
Refer to Figure 9-5. The screen now displays channels 1, 2, and 3 turned on and channels 1 and 3 with a
50 dB alternate amplitude setting. Also, the RF annunciator is turned on, and the new power level is
shown in the amplitude area of the display.
Figure 9-5
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Synchronizing to the BCH Then the TCH
The following steps show you how to synchronize to the broadcast channel (BCH). Set up the base station
and start sending the BCH signal now. The BCH is only required to contain the synchronization logical
channel (SCH).
1. Follow the instructions under “Configuring GSM Mode on the Agilent Technologies E4406A VSA
Series Transmitter Tester” and “Configuring GSM Mode on the ESG Vector Signal Generator” in this
chapter, to prepare the test equipment for synchronization.
2. Press Aux Fctn > BERT > BTS BERT GSM Loopback.
3. Press Sync Source BCH TCH/PDCH to BCH.
4. Press GSM BERT Off On to On > Synchronize to BCH/TCH/PDCH. Refer to Figure 9-6 on page 279. You will
briefly see Synchronizing to BCH flashing on the display.
Figure 9-6
Once synchronization is achieved, the ESG will expect to receive a TCH to decode and, accordingly, will
display the Waiting for TCH message. Refer to Figure 9-7.
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Figure 9-7
5. Turn off the BCH signal. and set up the base station to send the TCH signal.
6. Set up the base station and start sending the TCH signal now. The TCH is only required to contain a
valid midamble.
7. On the ESG, press Configure Measurement > Timeslot # > 2 > Enter.
This sets the ESG to expect the TCH in timeslot 2.
8. Press Return > Synchronize to BCH/TCH/PDCH to begin synchronization to the TCH.
NOTE
For the EDGE format, do the following to achieve TCH Sync Lock:
Press Configure Measurement > Timeslot # > 2 > Enter > Return > Adjust Gain.
Then you will see Synchronizing to TCH flashing on the display followed by the Synchronizing
to PN message.
Once synchronization is achieved, the Ready TCH Sync Lock message is displayed. Refer to Figure
9-8.
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Figure 9-8
Synchronizing to the TCH
The following steps show you how to synchronize to the traffic channel. The TCH is only required to
contain a valid midamble. If appropriate for your base station, this synchronization can be performed
without prior BCH synchronization.
NOTE
If the base station is transmitting a BCH signal, turn it off at this time.
1. Follow the instructions under “Configuring GSM Mode on the Agilent Technologies E4406A VSA
Series Transmitter Tester” and “Configuring GSM Mode on the ESG Vector Signal Generator” in this
chapter, to prepare the test equipment for synchronization.
2. Set up the base station and start sending the TCH signal now. The TCH is only required to contain a
valid midamble.
3. On the ESG, press Aux Fctn > BERT > BTS BERT GSM Loopback.
4. Press Sync Source BCH TCH/PDCH to TCH/PDCH.
5. Press Configure Measurement > Timeslot # > 2 > Enter.
This sets the ESG to expect the TCH in timeslot 2.
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6. Press Return > GSM BERT Off On to On.
NOTE
If the following error message is generated:
522 Demodulator Unleveled; Input amplitude underrange
this indicates that the TCH signal is not being received.
7. Press Synchronize to BCH/TCH/PDCH to begin synchronization to the TCH.
Then you will see Synchronizing to TCH flashing on the display followed by the Synchronizing
to PN message.
Once synchronization is achieved, the Ready TCH Sync Lock message is displayed. Refer to Figure
9-9.
Figure 9-9
Making Loopback BERT Measurements
The following procedure shows you how to configure the frame count, set pass/fail limits and set early stop
criteria for loopback BERT measurements.
1. Press Configure Measurement > Measurement Mode BER/BLER% Search to BER/BLER%.
2. Press BER/BLER% Configure > BER% TCH/FS Configure.
3. Press Frame Count > 100 > Enter.
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4. Press Pass/Fail Limits > Class II RBER > 2 > %.
5. Press Return > Threshold # of Events to Stop > Class II Bit Error > 300 > Enter.
Notice that the Class II Bit Error softkey is highlighted, 300 events is displayed beneath the softkey, and
Stop Thrs: CII(300) appears in the status area of the display.
Figure 9-10
6. Press the Trigger hardkey to start the measurement:
You will see Pass or Fail displayed on the lower left corner of the screen, when either of the following
occurs:
•
The measurement completes normally; in this case, after 100 frames.
•
The measurement terminates early, due to the designated number of events to stop being reached.
Refer to Figure 9-11 on page 284.
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Figure 9-11
NOTE
To select an alternate trigger mode (for example, Immediate):
Press Return three times, then press Configure Triggers >
BERT Trigger Source > Immediate.
Using Amplitude Sensitivity Search
This procedure shows you how to set a pass amplitude with high and low amplitude boundaries, and how to
set both the target error percentage, and the frame count for an amplitude sensitivity search.
1. Press Aux Fctn > BERT > BTS BERT GSM Loopback.
2. Press Configure Measurement > Measurement Mode BER/BLER% Search to Search.
Notice that the Configure Sensitivity Search and Arm Sensitivity Search softkeys are enabled.
3. Press Configure Sensitivity Search to access the softkey menu for configuring the sensitivity search. Refer
to Figure 9-12 on page 285.
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Figure 9-12
4. Press Frame Count > 100 > Enter.
5. Press Target % > 2 > %.
6. Press Pass Amplitude > −95 > dBm.
7. Press High Amplitude > −86 > dBm.
8. Press Low Amplitude > −104 > dBm.
9. Press Return > Arm Sensitivity Search. Sensitivity search is now armed, refer to Figure 9-13.
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Figure 9-13
10. Press Trigger to start the measurement:
After the search is complete, Pass or Fail is displayed on the lower left corner of the screen, when
either of the following occurs:
•
The result equals or is less than the target percent within the high to low amplitude range.
•
The high or low amplitude level is passed at the target% BER/RBER.
Refer to Figure 9-14.
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Figure 9-14
11. Press Stop Sensitivity Search to terminate a measurement:
NOTE
To select an alternate trigger mode (for example, Immediate):
Press Return > Configure Triggers > BERT Trigger Source > Immediate.
NOTE
Chapter 9
For efficiency, the search routine uses shorter measurements initially with the final
measurements being over the frame length selected.
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Using the External Frame Trigger Function with the EDGE Format
Using the External Frame Trigger Function with the EDGE Format
NOTE
This function is available only when the Frame Trigger Source BCH PDCH is set to PDCH.
The External Frame Trigger Function is used to adjust the burst timing at PDCH synchronization. This
requires calculating a delay value and then adjusting the initial value.
Measuring the Initial Delay Value
1. Configure the BTS and the VSA setup. Refer to Figure 9-15.
Figure 9-15
System Configuration for Measuring External Delay Value
2. Set up the BTS to transmit the frame trigger EDGE burst at timeslot 0.
3. On the VSA, press Mode > EDGE w/GSM.
4. Press Measure > Waveform (Time Domain).
5. Press Meas Setup > Trig Source > Ext Front.
6. Press Makers.
7. Use the marker function to find the offset value (D), in microseconds, between the BTS frame trigger
and the starting edge of the midamble. Refer to Figure 9-16 on page 289.
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Using the External Frame Trigger Function with the EDGE Format
Figure 9-16
8. Calculate the offset value X using the following equation:
X ( symbols ) = ( D – 227.8 ) ⁄ 3.693
Where, in the EDGE mode, 3.693 µs is equal to 1 symbol.
Adjusting the Delay Value
1. Configure the ESG, BTS, and VSA setup. Refer to Figure 9-17 on page 290.
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Figure 9-17
2. Press Aux Fctn > BERT > BTS BERT EDGE Loopback.
3. Press EDGE BERT to On > Configure Triggers.
4. Press Frame Trigger Source BCH PDCH to PDCH.
5. Press Configure Triggers > Frame Trigger Source Int Ext to Ext.
6. Press Ext Frame Trigger Delay and enter the X value calculated in the previous section.
NOTE
If the frame trigger is in the forward direction of timeslot 0, as shown in Figure 9-16 on
page 289, enter the X value as a negative value.
7. Press Return > Synchronize to BCH/PDCH.
Synchronization should occur and display a Ready status. However, if Synchronizing keeps flashing
or the Ready status appears for less than a second, increase or decrease the delay value by 2 symbols and
press the Synchronize to BCH/PDCH softkey again. Repeat this process until the Ready status
(synchronization) becomes stable.
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8. Press Configure Triggers > Ext Frame Trigger Delay.
9. Change the delay value by rotating the knob slowly to find the range of delay values that display a
Ready status.
NOTE
Although the delay value can be entered in 0.25 units, the actual uplink burst position can
be changed in 1.0 symbol units.
10. If the PDCH is synchronized by a delay value within a ±3 symbol range, choose the center value to set as
the frame trigger delay.
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Bit Error Rate Tester–Option UN7
Bit Error Rate Tester–Option UN7
The bit error rate test (BERT) capability allows you to perform bit error rate (BER) analysis on digital
communications equipment. This enables functional and parametric testing of receivers and components
including sensitivity and selectivity.
Block Diagram
When measuring BER, a clock signal that corresponds to the unit under test (UUT) output data must be
input to the BER CLK IN connector. If the clock is not available from the UUT, use the DATA CLK OUT
signal from the ESG baseband modulator.
Figure 9-18
Clock Gate Function
When you use the clock gate function, the clock signal to the BER CLK IN connector is valid only when the
clock gate signal to the BER GATE IN connector is ON.
Press the Clock Gate Off On softkey to toggle the clock gate function off and on.The Clock Gate Polarity Neg Pos
softkey sets the input polarity of the clock gate signal supplied to the rear panel BER GATE IN connector.
When you select Pos (positive), the clock signal is valid when the clock gate signal is high; when you select
Neg (negative), the clock signal is valid when the clock gate signal is low.
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The following figure shows an example of the clock gate signal.
Figure 9-19
•
When the Clock Gate Off On softkey is set to Off:
The clock signal in both “A” and “B” parts is effective and no gate function is required. Therefore, the
bit error rate is measured using the clock and data signal in both “A” and “B” parts.
•
When the Clock Gate Off On softkey is set to On, and the Clock Gate Polarity Neg Pos softkey is set to Pos:
The clock signal in “A” part is effective. Therefore, the bit error rate is measured using the clock and
data signals in “A” part.
•
When the Clock Gate Off On softkey is set to On, and the Clock Gate Polarity Neg Pos softkey is set to Neg:
The clock signal in “B” part is effective. Therefore, the bit error rate is measured using the clock and
data signals in “B” part.
Clock/Gate Delay Function
This function enables you to restore the timing relationship between the clock/gate timing as it passes
through the unit under test (UUT) and the packet data.
The shifted clock signal is emitted from pin 20 of the AUX I/O rear panel connector. When you use the
clock delay function, the clock signal to the BER CLK IN connector is delayed by the clock delay function.
When you use the gate delay function with the clock gate function, the clock signal is gated by the gate
signal which is delayed by the gate delay function.
To see the signal flow using the clock and gate functions, refer to Figure 9-20.
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Figure 9-20
Clock Delay Function
In this example, the clock delay function is off. Figure 9-21 shows the input of the internal error detector of
UN7 through AUX I/O and indicates that the data is delayed from the clock.
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Figure 9-21
CH1
CH2
CH1: BER TEST OUT (pin 20 of AUX I/O connector)
CH2: BER MEAS END (pin 1 of AUX I/O connector)
In this example, the clock delay function is on. The rising edge of the clock was delayed by 200 ns and was
adjusted to the center of the data. Figure 9-22 indicates the result of the using the clock delay function.
Figure 9-22
CH1
CH2
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Gate Delay Function in the Clock Mode
To use this function, the clock must be set to continuous mode.
In this example, the clock is used to delay the gate function. The clock of the internal error detector was
gated by the gate signal which is delayed by two clocks. Figure 9-23 shows that CH0 and CH1 are the input
of the clock and data from the rear panel input connectors of UN7. CH2 is the gated clock through the AUX
I/O connector.
Figure 9-23
CH0
CH1
CH2
CH0: BER CLK IN (rear panel SMB connector)
CH1: BER GATE IN (rear panel SMB connector)
CH2: BER TEST OUT (pin 20 of AUX I/O connector)
Triggering
This section describes the operating principles of the triggering function for Option UN7. To see the signal
flow of the triggering function refer to Figure 9-24.
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Figure 9-24
In this example, the triggering sequence is where you have an incoming data clock and data bit sequences,
the trigger is active, and the BERT measurement begins. Refer to Figure 9-25.
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Figure 9-25
In this example, synchronization occurs after receiving a trigger.
The reference data is generated by stored data bits. If the BERT measurement accepts data bits immediately
after receiving a trigger, set the trigger delay to On and the trigger delay count to a value corresponding to
the data format. For PN9 set the delay to 9. Refer to Figure 9-26.
Figure 9-26
In this example, the triggering sequence is where the trigger delay is active with a cycle count.
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The reference data is generated by stored data bits. If the BERT measurement accepts data bits immediately
after receiving a trigger, set the trigger delay to On and the trigger delay count to a value corresponding to
the data format. For PN9 set the delay to 9. If the cycle count is set to more than 1, it is not necessary to store
data bits and no unnecessary delay occurs. Refer to Figure 9-27 and “Repeat Measurements” on page 300.
Figure 9-27
Data Processing
Data Rates
Data rates up to 60 MHz are supported for BERT analysis on un-framed or framed PN sequences. Note that
the BERT analyzer supports only continuous PN sequences.
Synchronization
Immediately after the trigger event, the DSP for the BERT measurement tries to establish synchronization
using the first incoming bit stream.
If the Bit Delay Off On softkey is set to On, the number of bits specified by the Delayed Bits are ignored. The
synchronization checking is repeated using an error-free bit string, lengthened by the Delayed Bits, until
synchronization is established.
When the BERT Resync Off On softkey is set to On, the BERT measurements will automatically be restarted if
the intermediate BERT measurement result exceeds the value specified by the BERT Resync Limits.
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Special Pattern Ignore Function
The special pattern ignore function is especially useful when performing BERT analysis on radios that
generate consecutive 0’s or 1’s data for traffic channels when they fail to detect the Unique Word or lose
synchronization. If 160 or more consecutive incoming data bits are either 1’s or 0’s, and the Spcl Pattern
Ignore Off On softkey is set to On, then all of the consecutive 0’s or 1’s are ignored. Select either 0’s or 1’s as
the data to ignore by using the Spcl Pattern 0’s 1’s softkey. The following figure shows an example of the
special pattern ignore function.
Figure 9-28
The 160 or more ignored bits can be anywhere in the PN sequence. The signal generator ignores these bits as
error, but they are counted in the PN sequence bit count.
Pass/Fail Judgement
There are two pass/fail judgement update modes: cycle end and fail hold. With cycle end selected, either
pass or fail judgement is made for the results of each measurement cycle. With fail hold selected, the fail
judgement is retained whenever a failure occurs during one loop of BERT repeat measurements. Fail hold
mode allows you to determine when a failure occurs at least once during an entire cycle of measurements.
Repeat Measurements
When the Cycle Count softkey is set to more than 1, the synchronization performed before the start of each
measurement is only executed the first time; then it keeps track of the clock signal and the PRBS generation
for the incoming data. This function can reduce the total time for BERT measurements. Also, once
synchronization is established, it is retained even if the BERT measurement result degrades. You may wish
to adjust the signal level to find a specific BERT value. However, once synchronization is lost in a repeat
sequence, it will not be restored until the initiation of a new sequence. The following figure shows an
example of the repeat measurements.
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Figure 9-29
Testing Signal Definitions
The timing diagram Figure 9-30, “Testing Signal Definitions,” shows the relationships between a trigger
event and the output signals at the BER MEAS END and BER TEST OUT connectors.
If a BER MEAS END signal stays high following a trigger event, the BERT measurement is in progress and
other trigger events are ignored. This state is stored in the status register and can be queried.
Figure 9-30
Chapter 9
Testing Signal Definitions
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•
T1 is a firmware handling time measured from a Trigger event to the rising edge of a BER MEAS END
signal.
•
T2 is a firmware handling time measured from the falling edge of a BER TEST OUT signal to the falling
edge of the BER MEAS END signal.
•
T3 is a minimum requirement time measured from the falling edge of the BER MEAS END signal to the
next trigger event. T3 should be greater than 0 second.
The pulse output of the BER TEST OUT for the Nth-1 test result ends prior to the falling edge of the BER
MEAS END signal for the Nth measurement; so you can use this edge to start latching the Nth test result.
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RF Loopback BER–Option 300
Synchronization
Synchronizing the test equipment to the base transceiver station (BTS) is a prerequisite to the BTS looping
back the selected traffic channel (TCH). This can be achieved in two ways: BCH Sync or TCH Sync.
BCH Sync
The BTS is set to transmit to the test equipment a BCH on timeslot 0 of a selected
absolute radio frequency channel number (ARFCN). The test equipment uses the BCH
signal to determine its required TCH transmit timing.
On completion, the BTS may be switched into loopback mode on any selected ARFCN
and timeslot number.
TCH Sync
This is a very quick mode of synchronization, but take care initially to set the receiver to
the correct timeslot number being transmitted by the BTS.
In this mode the base station must transmit a signal on the selected timeslot prior to data
being looped back. In some base stations this will happen as soon as a timeslot is set to
loopback, regardless of whether the signal to the BTS has the correct timing. In other
base stations, the BTS may need to be set to transmit a signal in the selected timeslot
prior to achieving synchronization.
The test equipment can lock to this signal if it contains the correct midamble. Once
synchronized, the test equipment uses this information to determine the required TCH
transmit timing. If the BTS is set accordingly, any timeslot can be transmitted with the
correct timing to enable it to be looped back by the BTS to the receiver (VSA/ESG).
NOTE
The TCH sync mode relies on the user to set the correct timeslot number into both ESG
transmitter and receiver during synchronization. Thereafter, the ESG can correctly test any
timeslot since its relative timing is defined.
This capability can be used to speed up testing of consecutive timeslots in manufacture.
TCH sync mode can be used to test all timeslots consecutively without changing a single
setting on the ESG/VSA. All that is required is to consecutively loopback each timeslot
using the BTS man-machine interface (MMI) and resynchronize and trigger the ESG.
PN synchronization is also a prerequisite to BERT measurements. This is automatic but is dependent on
prior BCH or TCH synchronization.
The pattern to be recognized (PN9 or PN15) is determined by the corresponding transmit timeslot pattern
selection.
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Erased Frame Detection
When an incorrect CRC in an uplink speech frame is detected by a BTS conforming to the GSM standards,
the BTS substitutes an all-zero speech frame.
In the loopback mode, the BTS transmitter then recodes this substituted zero speech frame before
transmission back to the test equipment receiver (VSA/ESG).
The ESG receiver detects any coded all-zeros speech frames in the returned downlink signal and increments
the (erased) frame event count.
Downlink Errors
The loopback method of measuring BTS receiver BERT quality requires a high quality downlink return path
which introduces no errors.
To cater for the situation where the downlink path is faulty, the VSA/ESG provides a measure of downlink
quality based on TCH payload errors detected by convolutional decoding of the return path. This records
errors introduced into the TCH between the downlink coding (BTS transmitter) and decoding (VSA/ESG)
processes and should normally be zero. For any payload errors detected during a measurement, the
measurement is extended by a speech frame for every downlink error detected.
If a downlink problem results in errors introduced into the downlink midamble, the measurement aborts,
providing further security against downlink problems.
Frame Structure
GSM Frame Structure
26-frame TCH multiframe structure.
Frames: Frame 12 (SACCH) and frame 25 (idle) empty.
Identical repetitive frames. Content as per ESG GSM capability.
GSM Received Data
The Table 9-1 shows the minimum requirements for the GSM received data frame structure during
synchronization to the BTS and during measurements.
Table 9-1
GSM Received Data
During BCH Synchronization
TS0
51-frame BCH Multiframe Structure
SCH in frames 1, 11, 21, 31, 41
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Table 9-1
GSM Received Data (Continued)
During BCH Synchronization
TS1-7
No SCH, but otherwise, don’t care
During TCH Synchronization
TSX
26-frame TCH Multiframe Structure
Frame 25 idle
Frame 12 don’t care
Other frames TCH
During Measurements
Timeslot under test
26-frame full-rate voice TCH Multiframe Structure
TCH
Frames 0-11, 13-24
Content determined by transmitted signal (looped by BTS except
for errored speech frames, i.e. speech frames with bad CRC)
Frames 12, 25
Don’t care
GSM Transmit Data
The minimum GSM transmit data requirements for the loopback test are a fully GSM-coded 26-channel
multiframe with either PN9 or PN15 in the payload. This is selected on the ESG by setting the timeslot
under test to normal and selecting the PN9 or PN15 multiframe PN pattern.
To meet the GSM standards requirements for full conformance, the adjacent timeslots should be loaded with
fully GSM-coded data. The ESG offers full flexibility of loading all timeslots.
Edge Frame Structure
52-frame PDCH multiframe structure.
Frames: 12 blocks of 4 frames, 2 idle frames, and 2 frames used for the PTCCH.
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Verifying BERT Operation
Verifying BERT Operation
This procedure verifies the operation of the signal generator’s bit error rate test (BERT) function. This test
can be performed as part of a daily validation routine or can be used whenever you want to check the validity
of your BERT measurements. This procedure only checks the signal generator’s BERT operation and does
not ensure system performance to specifications.
Verification Setup
The following steps set up the signal generator for the BERT measurement validation.
1. Refer to the figures below and make the following connections on the signal generator’s rear panel.
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•
DATA OUT (Aux I/O connector pin 8) to BER DATA IN (SMB connector).
•
DATA CLK OUT (Aux I/O connector pin 7) to BER CLK IN (SMB connector).
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2. Press the Preset hardkey. This configures the signal generator to a pre-defined state.
3. Press the Mode hardkey.
4. Press Real TDMA > PHS > Data Format to Pattern.
5. Press Data > PN Sequence > PN9 > PHS Off On to On.
6. Press the Aux Fctn hardkey.
7. Press BERT > BERT Off On to On > Display BER % Exp to % > Display Update Cycle End Cont to Cont.
The following steps configure BERT measurement parameters.
8. Press Configure BERT > Total Bits to 100000 > Special Pattern Ignore Off On to Off.
9. Press More (1 of 2) > BERT Resync Off On to Off > Pass/Fail Off On to Off.
10. Press Return > I/O Setup > Gate Off On to Off > Impedance 75 Ohm High to High.
11. Press Polarity Setup > Clock Polarity Pos Neg to Neg > Data Polarity Pos Neg to Pos.
12. Press Return > Return > Configure Trigger > Cycle Count 0 > Enter.
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13. Press Bit Delay Off On to Off > BERT Trigger to Trigger Key.
14. Press the Trigger hardkey. The following figure shows the signal generator’s front-panel display after
completion of the these steps.
BERT Verification
1. Press BERT Trigger to Immediate.
Notice the cycle counter updating in the lower left-hand corner of the signal generator display.
2. Disconnect the cable connecting the DATA OUT to BER DATA IN connectors.
Notice the No Data annunciator in the lower left corner of the display and the BER result is
approximately 50%. The Error Bits counter updates the error bit count. Re-establishing the connection
turns the annunciator off, and sets the error bits count to 0 bits and BER 0.00000000%.
3. Disconnect the cable connecting the DATA CLK OUT to BER CLK IN connectors.
Notice the No Clock annunciator in the lower left corner of the display. This annunciator turns off
when you re-connect the cable, but the error bits counter and BER % readings indicate loss of
synchronization.
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4. Press Return.
Toggle the BERT Off On softkey to Off and to On. You will see the new BER result as shown in the
previous front-panel display with the Error Bits counter reading 0 Bits and BER 0.00000000%.
If the verification procedures produce the expected results, then the signal generator BERT measurement
function is operating correctly. If the above procedure produces unexpected results, then contact the Agilent
Service Center. For a list of Agilent Service Centers, refer to the E4428C/38C ESG Signal Generators
Installation Guide.
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10 CDMA Digital Modulation (Option 401)
Option 401 is available only in E4438C ESG Vector Signal Generators with Option 001/601 or 002/602. The
following list shows the topics covered in this chapter:
•
“cdma2000 Forward Link Modulation for Component Test” on page 312
•
“cdma2000 Reverse Link Modulation for Component Test” on page 316
•
“Storing a Component Test Waveform to Memory” on page 320
•
“Recalling a Component Test Waveform” on page 321
•
“Creating a Custom Multicarrier cdma2000 Waveform” on page 322
•
“cdma2000 Forward Link Modulation for Receiver Test” on page 326
•
“cdma2000 Reverse Link Modulation for Receiver Test” on page 332
•
“Forward and Reverse Link I/O Signal Descriptions and Timing Relationships” on page 338
•
“Applying a User-Defined FIR Filter to a cdma2000 Waveform” on page 347
•
“IS-95A Modulation” on page 349
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cdma2000 Forward Link Modulation for Component Test
cdma2000 Forward Link Modulation for Component Test
This section teaches you how to build forward link cdma2000 waveforms for testing component designs.
The waveforms are generated by the signal generator’s internal dual arbitrary waveform generator.
Activating a Predefined CDMA Forward Link State
This procedure teaches you how to perform the following tasks:
•
“Selecting a cdma2000 Forward Link Predefined Setup” on page 312
•
“Generating the Waveform” on page 312
•
“Configuring the RF Output” on page 312
Selecting a cdma2000 Forward Link Predefined Setup
1. Press Preset.
2. Press Mode > CDMA > Arb CDMA2000.
3. Press CDMA2000 Select > Pilot.
This selects a pilot cdma2000 forward link waveform. The display changes to FWD CDMA2000 Setup:
SR1 Pilot. Forward link is the default setting for link direction, and therefore does not need to be set.
Generating the Waveform
Press CDMA Off On until On is highlighted.
This generates the predefined pilot CDMA forward link waveform. During waveform generation, the CDMA
and I/Q annunciators appear and the waveform is stored in volatile Arb memory. The waveform is now
modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 2.17 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off until On is highlighted.
The predefined CDMA forward link signal is now available at the RF OUTPUT connector of the signal
generator.
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Creating a User-Defined CDMA Forward Link State
This procedure teaches you how to perform the following tasks:
•
“Accessing the Table Editor with the Default Forward Link Setup” on page 313
•
“Editing cdma2000 Forward Link Channel Parameters” on page 313
•
“Inserting Additional cdma2000 Forward Link Traffic Channels” on page 315
Accessing the Table Editor with the Default Forward Link Setup
1. Press Preset.
2. Press Mode > CDMA > Arb CDMA2000.
3. Press More (1 of 2) > CDMA200 Define > Edit Channel Setup.
The table editor is now displayed, as shown in Figure 10-1. Notice that the default predefined channel
configuration is forward link with 9 channels at spread rate 1. The vertical scroll bar at the side of the screen
indicates that there are more rows on the second page. Use the down arrow key to move the cursor to view
additional rows.
Figure 10-1
Editing cdma2000 Forward Link Channel Parameters
1. Use the arrow keys to move the cursor to the traffic channel located in table row 3.
2. Highlight the Rate bps value (9600).
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3. Press Edit Item > 4800.
4. Highlight the Walsh code value (8) in table row 3.
5. Press Edit Item > 3 > Enter.
6. Highlight the Power value (−12.72) in table row 3.
7. Press Edit Item > −10 > dB.
The display shows that the total power is now at 0.19 dB. You can rescale the total channel power to
0 dB by pressing Adjust Code Domain Power > Scale to 0 dB.
8. Highlight the Data value (RANDOM) in table row 3.
9. Press Edit Item > 11001100 > Enter.
The forward link channel parameters have now been modified, as shown in Figure 10-2.
Figure 10-2
10. Press Return.
The text area displays FWD CDMA2000 Setup: SR1 9 Channel (Modified) as the current
configuration. You now have a modified traffic channel with a data rate of 4800, a Walsh code of 3 and a
power level of −10.00 dB transmitting 11001100.
To store a custom cdma2000 state, see “Storing a Component Test Waveform to Memory” on page 320.
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Inserting Additional cdma2000 Forward Link Traffic Channels
1. Press Edit Channel Setup.
2. Move cursor to the bottom row and press Insert Row > Traffic > Channels > 20 > Enter.
3. Press Done.
The channel table editor now contains the 20 additional channels. The first page displays only channels one
through nine. To see the additional channels, press the following key sequence:
Return > Goto Row > Page Up.
The display shows that the total power is now at 13.22 dB. You can rescale the total channel power to 0 dB
by pressing Adjust Code Domain Power > Scale to 0 dB.
Press Return. The text area displays the current configuration, FWD CDMA2000 Setup: SR1 9 Channel
(Modified), as shown in Figure 10-3.
Figure 10-3
To store a custom cdma2000 state, see “Storing a Component Test Waveform to Memory” on page 320.
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cdma2000 Reverse Link Modulation for Component Test
cdma2000 Reverse Link Modulation for Component Test
This section teaches you how to build reverse link cdma2000 waveforms for testing component designs. The
waveforms are generated by the signal generator’s internal dual arbitrary waveform generator.
Activating a Predefined cdma2000 Reverse Link State
This procedure teaches you how to perform the following tasks:
•
“Selecting a Predefined cdma2000 Reverse Link Setup” on page 316
•
“Generating the Waveform” on page 316
•
“Configuring the RF Output” on page 316
Selecting a Predefined cdma2000 Reverse Link Setup
1. Press Preset.
2. Press Mode > CDMA > Arb CDMA2000.
3. Press Link Forward Reverse until Reverse is highlighted.
4. Press CDMA2000 Select > Pilot.
This selects a pilot cdma2000 reverse link waveform. The display changes to FWD CDMA2000 Setup:
SR1 Pilot.
Generating the Waveform
Press CDMA Off On until On is highlighted.
This generates the predefined pilot cdma2000 reverse link waveform. During waveform generation, the
CDMA and I/Q annunciators appear and the waveform is stored in volatile Arb memory. The waveform is
now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 2.17 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off until On is highlighted.
The predefined cdma2000 reverse signal is now available at the RF OUTPUT connector of the signal
generator.
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Creating a User-Defined cdma2000 Reverse Link State
This procedure teaches you how to perform the following tasks:
•
“Accessing the Table Editor with the Default Reverse Link Setup” on page 317
•
“Editing cdma2000 Reverse Link Channel Parameters” on page 317
•
“Inserting Additional cdma2000 Reverse Link Traffic Channels” on page 318
Accessing the Table Editor with the Default Reverse Link Setup
1. Press Preset.
2. Press Mode > CDMA > Arb CDMA2000.
3. Press Link Forward Reverse until Reverse is highlighted.
4. Press More (1 of 2) > CDMA200 Define > Edit Channel Setup.
The table editor is now displayed, as shown in Figure 10-4. Notice that the default predefined channel
configuration is reverse link with 5 channels at spread rate 1.
Figure 10-4
Editing cdma2000 Reverse Link Channel Parameters
1. Use the arrow keys to move the cursor to the traffic channel located in table row 3.
2. Highlight the Rate bps value (9600).
3. Press Edit Item > 4800.
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4. Highlight the Power value (–17.36) in table row 3.
5. Press Edit Item > −10 > dB.
The display shows that the total power is now at 0.34 dB. You can rescale the total channel power to
0 dB by pressing Adjust Code Domain Power > Scale to 0 dB.
6. Highlight the Data value (RANDOM) in table row 3.
7. Press Edit Item > 00110011 > Enter.
The forward reverse channel parameters have now been modified, as shown in Figure 10-5.
Figure 10-5
8.
Press Return.
The text area displays RVS CDMA2000 Setup: SR1 5 Channel (Modified) as the current
configuration. You now have a modified traffic channel with a data rate of 4800 and a power level of −10.00
dB transmitting 00110011.
To store a custom cdma2000 state, see “Storing a Component Test Waveform to Memory” on page 320.
Inserting Additional cdma2000 Reverse Link Traffic Channels
1. Press Edit Channel Setup.
2. Move cursor to the bottom row and press Insert Row > Supplemental2 Traffic.
3. Press Done.
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The channel table editor now contains the an additional supplemental2 traffic channel.
The display shows that the total power is now at 1.37 dB. You can rescale the total channel power to 0 dB by
pressing Adjust Code Domain Power > Scale to 0 dB.
Press Return > Return.
The text area displays the current configuration, RVS CDMA2000 Setup: SR1 5 Channel
(Modified), as shown in Figure 10-6.
Figure 10-6
To store a custom cdma2000 state, see “Storing a Component Test Waveform to Memory” on page 320.
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Storing a Component Test Waveform to Memory
Storing a Component Test Waveform to Memory
In this section, you will learn how to store the component test waveform.
1. Press Mode Setup hardkey to return to the top-level menu.
2. Perform the following keypress sequence required for your format type.
For CDMA2000 Waveform Format
a. Press More (1 of 2) > CDMA2000 Define (Multicarrier Define when Multicarrier Off On is On) > Store Custom
CDMA State (Store Custom Multicarrier when Multicarrier Off On is On) > Store To File.
If there is already a file name occupying the active entry area, press the following keys:
Edit Keys > Clear Text
b. Using the alphabetic menu and the numeric keypad, enter the file name using a maximum length of
23 characters.
c. Press Enter.
For CDMA Waveform Format
a. Press CDMA Define (Multicarrier Define when Multicarrier Off On is On) > Store Custom State (Store Custom
Multicarrier when Multicarrier Off On is On > Store To File.
If there is already a file name occupying the active entry area, press the following keys:
Edit Keys > Clear Text
b. Using the alphabetic menu and the numeric keypad, enter the file name.
c. Press Enter.
Your user-defined CDMA state file is now saved to the signal generator memory.
NOTE
320
The RF output amplitude, frequency, and operating state settings are not stored as part of a
user-defined CDMA state file.
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CDMA Digital Modulation (Option 401)
Recalling a Component Test Waveform
Recalling a Component Test Waveform
In this section, you will learn how to recall a component test waveform.
1. Press Mode Setup hardkey to return to the top-level menu.
2. Perform the following keypress sequence required for your format type.
For CDMA2000 Waveform Format
a. Press CDMA2000 Select > Custom CDMA2000 State (Custom CDMA2000 Multicarrier when Multicarrier Off
On is On).
b. Highlight the desired file.
c. Press Select File.
d. Press CDMA2000 Off On until On is highlighted.
For CDMA Waveform Format
a. Press Setup Select > Custom CDMA State (Custom CDMA Multicarrier when Multicarrier Off On is On).
b. Highlight the desired file.
c. Press Select File.
d. Press CDMA Off On until On is highlighted.
The firmware generates the user-defined CDMA waveform in volatile memory. After waveform generation,
the user-defined CDMA state is available to be modulated on the RF output.
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Creating a Custom Multicarrier cdma2000 Waveform
Creating a Custom Multicarrier cdma2000 Waveform
The signal generator provides a quick and easy way to create custom multicarrier cdma2000 waveforms:
rather than building an entire 4-carrier setup from scratch, you can start with a 4-carrier cdma2000 template
and modify the template’s default values as desired.
This section teaches you how to perform the following tasks:
•
“Opening the Multicarrier cdma2000 Setup Table Editor” on page 322
•
“Modifying a Multicarrier cdma2000 4-Carrier Template” on page 323
•
“Activating a Custom Multicarrier cdma2000 Setup” on page 324
•
“Storing a Component Test Waveform to Memory” on page 320
•
“Recalling a Component Test Waveform” on page 321
Opening the Multicarrier cdma2000 Setup Table Editor
1. Press Preset.
2. Press Mode > CDMA > Arb CDMA2000 > Multicarrier Off On until On is highlighted.
3. Press CDMA2000 Select > 4 Carriers.
4. Press More (1 of 2) > Multicarrier Define.
This opens the Multicarrier cdma2000 Setup table editor. The 4-carrier cdma2000 template is automatically
placed in the table editor, as shown in Figure 10-7 on page 323.
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Figure 10-7
Modifying a Multicarrier cdma2000 4-Carrier Template
Use the tasks to modify the standard 4-carrier cdma2000 template that was loaded in the previous procedure.
1. Highlight the second channel carrier in table row 2.
2. Press Edit Item > SR3 Direct Pilot.
3. Highlight the value –625.000 kHz in the Frequency Offset field.
4. Press Edit Item > –825 > kHz.
5. Highlight the value 0.00 dB in Power field of the second row.
6. Press Edit Item > –10 > dB.
This modifies the 4-carrier cdma2000 template, as shown in Figure 10-8 on page 324.
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Figure 10-8
Activating a Custom Multicarrier cdma2000 Setup
Using the custom 4-carrier cdma2000 setup from the previous procedure, perform the following task to
activate the custom multicarrier cdma2000 signal.
1. Press Return > More (2 of 2) > CDMA2000 Off On until On is highlighted.
2. Press RF On/Off.
Figure 10-9
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Creating a Custom Multicarrier cdma2000 Waveform
After waveform generation, the new multicarrier cdma2000 waveform is stored in volatile memory. The
CDMA2K and I/Q annunciators appear on the display and the RF ON annunciator replaces the RF OFF
annunciator, as shown in the following figure. The modulated signal is now present at the RF OUTPUT
connector.
To store a custom multicarrier waveform, refer to “Storing a Component Test Waveform to Memory” on
page 320.
To recall a custom multicarrier waveform, refer to “Recalling a Component Test Waveform” on page 321.
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cdma2000 Forward Link Modulation for Receiver Test
This section teaches you how to build cdma2000 forward link signals for testing mobile receiver designs.
The signals are generated by the internal real time IQ baseband generator. The procedures in this section
build on each other and are designed to be used sequentially.
Editing the Base Station Setup
1. Press Preset.
2. Press Mode > CDMA > Real Time CDMA2000.
NOTE
The forward link is the signal generator’s default setting for link direction and, therefore,
does not need to be set.
3. Press BaseStation Setup.
4. Move the cursor to highlight the filter field.
5. Press Edit Item > Select > IS-95 and IS-2000 > IS-95.
6. Press Return > Return.
7. Press BaseStation Setup.
8. Move the cursor to highlight the PN Offset field.
9. Press 9 > Enter.
The cdma2000 forward link global parameters have now been modified so that you are using an IS-95 filter
and a PN offset of 9.
Editing Channel Setups
The tasks in this procedure build upon the previous procedure. This procedure teaches you how to perform
the following tasks:
•
“Changing Channel States” on page 327
•
“Modifying Channel Parameters” on page 327
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Changing Channel States
This task teaches you how to quickly configure the operating states of the forward link channels.
1. Press Mode Setup to return to the top-level real time cdma2000 menu.
2. Press Link Control > Channel State Quick Presets > All (Except FQPCH).
You have now turned on all forward link channels, except for the forward link quick paging channel
(F-QPCH). The Channel State Quick Presets menu enables you to configure the operating states of all
channels with a single keypress. You can also change the operating state of the selected channel using the
Channel State Off On softkey, or by editing the State field among the Channel Setup parameters.
Modifying Channel Parameters
This task teaches you how to edit the parameters for the selected channel.
1. Move the cursor to highlight the forward fundamental channel (F-FCH).
2. Press Channel Setup.
3. Move the cursor to highlight the Radio Config field.
4. Press 4 > Enter.
NOTE
An important change from earlier ESG models is that radio configuration is now
independent between fundamental and supplemental channels.
5. Move the cursor to highlight the Data field.
6. Press Edit Item > FIX4 > 1010 > Enter > Return.
7. Move the cursor to highlight the Power field.
8. Press −10 > dB.
9. Move the cursor to highlight the EbNo field.
10. Press 12 > dB > Return.
You have now modified the forward fundamental channel parameters so that the radio configuration is 4, the
data is a fixed 4-bit pattern of 1010, the relative channel power is −10 dB, and EbNo value is 12 dB.
Figure 10-10 on page 328 shows what the display should look like when this task is completed.
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Figure 10-10
Forward Fundamental Channel (F-FCH) Setup
Note that the ESG allows you to set the relative channel power for each active channel. To display the
normalized relative channel power after completing the setup, it is recommended that you perform the steps
in “Adjusting Code Domain Power” on page 328. Also note that varying the EbNo value on one channel will
affect the EbNo values on all active channels. Refer to “Managing Noise” on page 329 to learn how to make
final noise adjustments.
Adjusting Code Domain Power
The tasks in this procedure build upon the previous procedure. This procedure teaches you how to perform
the following tasks:
•
“Scaling to 0 dB” on page 328
•
“Setting Equal Channel Powers” on page 329
Scaling to 0 dB
After changing the relative power level for a channel, the ESG automatically scales the total power to 0 dB,
while preserving the relative channel power levels. The displayed power levels remain unchanged so the
user can complete the relative power adjustments. This task teaches you how to update the display to show
the normalized relative channel power for each channel after completing the setup.
1. Press Mode Setup to return to the top-level real time cdma2000 menu.
2. Press Link Control > Adjust Code Domain Power > Scale to 0 dB.
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The power level displayed for each channel is now changed to show the normalized relative channel power.
Figure 10-11 shows the displayed power levels before and after the Scale to 0 dB softkey is pressed.
Figure 10-11
Displayed Power Levels
Before Scaling to 0 dB
Displayed Power Levels
After Scaling to 0 dB
Setting Equal Channel Powers
This task teaches you how to set the relative power level for all active channels to be equal, for a total power
level of 0 dB. The normalized relative power level of each channel depends on the number of active
channels. This task is an alternative to scaling to 0 dB.
Press Adjust Code Domain Power > Equal Powers.
All active channels have now been set to equal powers. Figure 10-12 shows the displayed normalized
relative power levels after the Equal Powers softkey is pressed with seven active channels.
Figure 10-12
Displayed Power Levels
After Equal Powers
Managing Noise
The tasks in this procedure build upon the previous procedure.
The following tasks teach you how to set the overall carrier-to-noise (C/N) ratio for the forward link
cdma2000 setup and to set the EbNo value for individual physical channels.
•
“Setting the Carrier to Noise Ratio” on page 330
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•
“Setting EbNo” on page 330
Setting the Carrier to Noise Ratio
1. Press Mode Setup to return to the top-level real time cdma2000 menu.
2. Press Noise Setup > C/N > 10 > dB.
3. Press Noise Off On to On.
You have now set the overall carrier to noise ratio to 10 dB and turned on noise. This is done to apply a
discernible level of noise across the entire channel space.
Setting EbNo
EbNo can be set in the Noise Setup menu or the Channel Setup table editor (see “Modifying Channel
Parameters” on page 327). This task teaches you how to make quick EbNo adjustments using the EbNo
softkey in the Noise Setup menu.
1. Press Channel Number and move the cursor to highlight the forward fundamental channel (F-FCH).
2. Press EbNo > 20 > dB.
You have now set the EbNo value for the F-FCH channel to 20 dB. Note that modifying the EbNo value for
a channel will change the overall carrier to noise ratio and the EbNo value for all other active channels. For
reliable results when making hand calculations to determine or verify EbNo values, it is recommended that
you first scale the code domain power to 0 dB to display the normalized relative channel power levels (see
“Scaling to 0 dB” on page 328).
Generating the Baseband Signal
This procedure builds upon the previous procedure.
Press CDMA2000 Off On to On.
This generates the real time forward link cdma2000 signal. The signal generator may require several
seconds to build the signal. During this time, Baseband Reconfiguring appears on the display. After
the reconfiguration is complete, the display reads CDMA2000 On and the CDMA2K and I/Q annunciators
appear. The signal is now modulating the RF carrier.
The signal’s configuration data resides in volatile memory and is not recoverable after an instrument preset,
power cycle, or reconfigured signal generation.
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Configuring the RF Output
The steps in this procedure build upon the previous procedure.
1. Set the RF output frequency to 2.14 GHz.
2. Set the output amplitude to −30 dBm.
3. Press RF On/Off to On.
The user-defined, real time forward link cdma2000 signal is now available at the signal generator’s RF
OUTPUT connector.
To store this real time I/Q baseband digital modulation state to the instrument state register, see “Using the
Instrument State Registers” on page 70.
To recall a real time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
For information on timing relationships, see “Forward and Reverse Link I/O Signal Descriptions and Timing
Relationships” on page 338.
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cdma2000 Reverse Link Modulation for Receiver Test
cdma2000 Reverse Link Modulation for Receiver Test
This section teaches you how to build cdma2000 reverse link signals for testing base station receiver
designs. The signals are generated by the internal real time IQ baseband generator. The procedures in this
section build on each other and are designed to be used sequentially.
Editing the Mobile Setup
1. Press Preset.
2. Press Mode > CDMA > Real Time CDMA2000 > Link Forward Reverse to Reverse.
3. Press Mobile Setup.
4. Move the cursor to highlight the filter field.
5. Press Edit Item > Select > IS-95 and IS-2000 > IS-95 Mod.
6. Press Return > Return.
7. Press Mobile Setup.
8. Move the cursor to highlight the Long Code Mask field.
9. Press 3FFF0000000 > Enter.
The cdma2000 reverse link global parameters have now been changed so that you are using a modified
IS-95 filter and a long code mask of 3FFF0000000.
Editing Channel Setups
The tasks in this procedure build upon the previous procedure. This procedure teaches you how to perform
the following tasks:
•
“Changing the Operating Mode” on page 332
•
“Changing Channel States” on page 333
•
“Modifying Channel Parameters” on page 333
Changing the Operating Mode
This task teaches you how to select a predefined reverse link channel configuration.
1. Press Mode Setup to return to the top-level real time cdma2000 menu.
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2. Press Link Control > Operating Mode > RadioConfig 1/2 Access.
Notice that the display shows a single reverse access channel. This is an IS-2000 standard channel
configuration. For learning purposes, we will change back to RadioConfig 3/4 Traffic, which is the
default operating mode.
3. Press Operating Mode > RadioConfig 3/4 Traffic.
You have now selected RadioConfig 3/4 Traffic as the current operating mode.
Changing Channel States
This task teaches you how to quickly configure the operating states of the reverse link channels.
Press Channel State Quick Presets > All.
You have now turned on all reverse link channels. The Channel State Quick Presets menu enables you to
configure the operating states of all channels with a single keypress. This menu is only available for the
reverse link when the RadioConfig 3/4 Traffic operating mode is selected. You can also change the operating
state of the selected channel using the Channel State Off On softkey, or by editing the State field among the
Channel Setup parameters.
Modifying Channel Parameters
This task teaches you how to edit the parameters for the selected channel.
1. Move the cursor to highlight the reverse fundamental channel (R-FCH).
2. Press Channel Setup.
3. Move the cursor to highlight the Radio Config field.
4. Press 4 > Enter.
NOTE
An important change from earlier ESG models is that radio configuration is now
independent between fundamental and supplemental channels.
5. Move the cursor to highlight the Data field.
6. Press Edit Item > FIX4 > 1010 > Enter > Return.
7. Move the cursor to highlight the Power field.
8. Press −10 > dB.
9. Move the cursor to highlight the EbNo field.
10. Press 12 > dB > Return.
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You have now modified the reverse fundamental channel parameters so that the radio configuration is 4, the
data is a fixed 4-bit pattern of 1010, the relative channel power is −10 dB, and EbNo value is 12 dB.
Figure 10-13 shows what the display should look like when this task is completed.
Figure 10-13
Reverse Fundamental Channel (R-FCH) Setup
Note that the ESG allows you to set the relative channel power for each active channel. To display the
normalized relative channel power after completing the setup, it is recommended that you perform the steps
in “Adjusting Code Domain Power” on page 334. Also note that varying the EbNo value on one channel will
affect the EbNo values on all active channels. Refer to “Managing Noise” on page 335 to learn how to make
final noise adjustments.
Adjusting Code Domain Power
The tasks in this procedure build upon the previous procedure. This procedure teaches you how to perform
the following tasks:
•
“Scaling to 0 dB” on page 334
•
“Setting Equal Channel Powers” on page 335
Scaling to 0 dB
After changing the relative power level for a channel, the ESG automatically scales the total power to 0 dB,
while preserving the relative channel power levels. The displayed power levels remain unchanged so the
user can complete the relative power adjustments. This task teaches you how to update the display to show
the normalized relative channel power for each channel after completing the setup.
1. Press Mode Setup to return to the top-level real time cdma2000 menu.
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2. Press Link Control > Adjust Code Domain Power > Scale to 0 dB.
The power level displayed for each channel is now changed to show the normalized relative channel power.
Figure 10-14 shows the displayed power levels before and after the Scale to 0 dB softkey is pressed.
Figure 10-14
Displayed Power Levels
Before Scaling to 0 dB
Displayed Power Levels
After Scaling to 0 dB
Setting Equal Channel Powers
This task teaches you how to set the relative power level for all active channels to be equal, for a total power
level of 0 dB. The normalized relative power level of each channel depends on the number of active
channels. This task is an alternative to scaling to 0 dB.
Press Adjust Code Domain Power > Equal Powers.
All active channels have now been set to equal powers. Figure 10-15 shows the displayed normalized
relative power levels after the Equal Powers softkey is pressed with five active channels.
Figure 10-15
Displayed Power Levels
After Equal Powers
Managing Noise
The tasks in this procedure build upon the previous procedure.
The following tasks teach you how to set the overall carrier-to-noise (C/N) ratio for the reverse link
cdma2000 setup and to set the EbNo value for individual physical channels.
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•
“Setting the Carrier to Noise Ratio” on page 336
•
“Setting EbNo” on page 336
Setting the Carrier to Noise Ratio
1. Press Mode Setup to return to the top-level real time cdma2000 menu.
2. Press Noise Setup > C/N > 10 > dB.
3. Press Noise Off On to On.
You have now set the overall carrier to noise ratio to 10 dB and turned on noise. This is done to apply a
discernible level of noise across the entire channel space.
Setting EbNo
EbNo can be set in the Noise Setup menu or the Channel Setup table editor (see “Modifying Channel
Parameters” on page 333). This task teaches you how to make quick EbNo adjustments using the EbNo
softkey in the Noise Setup menu.
1. Press Channel Number and move the cursor to highlight the reverse fundamental channel (R-FCH).
2. Press EbNo > 20 > dB.
You have now set the EbNo value for the R-FCH channel to 20 dB. Note that modifying the EbNo value for
a channel will change the overall carrier to noise ratio and the EbNo value for all other active channels. For
reliable results when making hand calculations to determine or verify EbNo values, it is recommended that
you first scale the code domain power to 0 dB to display the normalized relative channel power levels (see
“Scaling to 0 dB” on page 334).
Generating the Baseband Signal
This procedure builds upon the previous procedure.
Press CDMA2000 Off On to On.
This generates the real time reverse link cdma2000 signal. The signal generator may require several seconds
to build the signal. During this time, Baseband Reconfiguring appears on the display. After the
reconfiguration is complete, the display reads CDMA2000 On and the CDMA2K and I/Q annunciators appear.
The signal is now modulating the RF carrier.
The signal’s configuration data resides in volatile memory and is not recoverable after an instrument preset,
power cycle, or reconfigured signal generation.
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Configuring the RF Output
The steps in this procedure build upon the previous procedure.
1. Set the RF output frequency to 2.14 GHz.
2. Set the output amplitude to −30 dBm.
3. Press RF On/Off to On.
The user defined, real time reverse link cdma2000 signal is now available at the signal generator’s RF
OUTPUT connector.
To store this real time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
For information on timing relationships, see “Forward and Reverse Link I/O Signal Descriptions and Timing
Relationships” on page 338.
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Forward and Reverse Link I/O Signal Descriptions and Timing Relationships
Forward and Reverse Link I/O Signal Descriptions and Timing Relationships
This section describes the functionality and timing relationships of the connector signals for forward and
reverse link on the ESG with Option 401. Option 401 changes some of the characteristics of the signals
normally present on some of the I/O connectors. This is done for cdma2000 applications. Some output
connectors have additional output signal selections, which are indicated in the descriptions.
The following connector descriptions are divided into three sections: front panel inputs, rear panel inputs,
and rear panel outputs. Diagrams showing the timing relationships between rear panel inputs and outputs
follow the connector descriptions.
Front Panel Inputs
DATA (Forward Link)
This front panel BNC connector is used for data input. The external data input can only be used by F-FSH or
F-SCH channels. If these two channel types are assigned external data, the same data is input to both the
F-FCH and F-SCH channels. Both channel types must be assigned radio configurations with the same
modulation symbol rate.
The serial data must be input at the modulation symbol rate and aligned with the internal F-FCH (or F-SCH)
modulation symbol clock. Coded and framed data must be aligned with internal frame timing.
For RC1 and RC2 channel types, the symbol data input timing aligns with internal frame timing. For RC3-5,
the I/Q symbol pair for a given frame position, must input two I/Q symbol pair periods before that frame
position. The I and Q symbol data is sampled at the end of the symbol period and must be stable.
The external data is input at the modulation symbol node and is spread with the decimated long code.
Subsequently, power control symbol puncturing (for F-FCH channel types only), Walsh coding, and I/Q
mapping are applied.
Serial data clock and frame timing can be generated from the chip clock and even second outputs. See the
following section, “Rear Panel Outputs” on page 339.
On signal generators with Option 1EM, this input is relocated to a rear panel SMB input.
DATA CLOCK (Forward and Reverse Link)
This BNC connector is used for a chip clock input. This input is used for the external reference input
(generally a 1.2288 MHz TTL or CMOS signal) for data and baseband generation. This input is active only
after toggling the baseband data generator clock from internal to external.
On signal generators with Option 1EM, this input is relocated to a rear panel SMB input.
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Rear Panel Inputs
ALT PWR IN (Forward Link)
Pin 16 of the AUX I/O connector is used for a long code state latch strobe input. The leading edge of the
long code state latch strobe input is latched and sampled by the chip clock. The current state of the long code
is latched and held until the next trigger input. Subsequently, the long code state held in the latch can be read
via the GPIB or RS-232 ports.
PATTERN TRIG IN (Forward and Reverse Link)
This BNC connector is used for a system reset trigger input. This system reset trigger ensures frame and
long code timing alignment. In addition, the trigger is used to align a reverse link configuration with the base
station. When the ESG is being used as a mobile station, the reset signal is provided by the BTS via the
PATTERN TRIG IN connector.
On signal generators with Option 1EM, this input is changed from a BNC to an SMB connector.
Rear Panel Outputs
DATA OUT (Forward Link)
Pin 7 of the AUX I/O connector is used for the power control group bit state output. This control bit is used
for power control puncturing during the current power control group. The output is aligned with data
generation timing and leads the baseband and RF outputs by approximately 28 chips (even second delay).
This output can be used to synchronize receiver measurements of mobile power output.
DATA OUT (Reverse Link)
Pin 7 of the AUX I/O connector is used for the long code output. This pin provides an external output for the
current long code being processed. The beginning of the long code occurs 2 chips after a system reset, leads
the SYMBOL SYNC OUT signal by 257 chips in RC1-2 and 1 chip in RC3-4, and leads the delayed even
second signal by approximately 28 chips (even second delay). The long code rear panel output occurs prior
to the RF output.
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DATA CLK OUT (Forward Link and Reverse Link)
Pin 6 of the AUX I/O connector provides an external output for the chip clock. The chip clock provides a
1.2288 MHz TTL signal with one-chip-wide pulses that is used for the timing to determine when events will
occur. The BTS timing and the system resync signals both start at the first available rising chip clock pulse
edge. All other signal start times are counted using the chip clock pulses relative to the first pulse occurrence
of the timing or resync signal. The trigger advance, even second delay, and the other internal leading chips,
relative to the delayed even second signal are counted using the one-chip-wide chip clock pulse.
In reverse link, there are other selectable clock rates: one group for RC1-2 and another for RC3-4.
EVENT 1 (Forward and Reverse Link)
This BNC connector is used for the delayed even second output. This connector provides a one-chip wide
signal output with variable delay from the internal data generation even second. The delay is adjustable (via
the front panel user interface or remote interface, Even Sec Delay) to allow even second alignment with
baseband and RF outputs. Data generation timing leads the baseband and RF output by approximately 28
chips (even second delay). In forward link there are two other trigger signals available: delayed 20 and 80
ms signals.
On signal generators with Option 1EM, this output is changed from a BNC to an SMB connector.
EVENT 2 (Forward Link)
This BNC connector is used for the system reset output. The system reset trigger outputs whenever a PN
offset value changes or differences in frame and long code timing alignment are apparent between the signal
generators.
On signal generators with Option 1EM, this output is changed from a BNC to an SMB connector.
EVENT 2 (Reverse Link)
This BNC connector is used for the system reset output. The system reset trigger occurs whenever the input
BTS timing signal (PATTERN TRIG IN connector) and the ESG’s delayed even second clock are not
aligned.
On signal generators with Option 1EM, this output is changed from a BNC to an SMB connector.
SYM SYNC OUT (Forward and Reverse Link)
Pin 5 of the AUX I/O connector is used for the even second output. The one-chip-wide even second signal is
aligned with the internal data generation timing. In reverse link, there is a Long Code Sync selection which
provides a trigger to signal the start of the long code.
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Forward Link I/O Timing Relationships
Refer to the following two timing diagrams (Figure 10-16 and Figure 10-17) for the forward link timing
relationships between the signals at the rear panel BNC/SMB/AUX I/O output and input connectors. Signal
states are referenced to the chip clock provided at the DATA CLK OUT connector.
Figure 10-16
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Forward Link Timing Diagram - Outputs
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Figure 10-17
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Forward Link Timing Diagram - Inputs
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Forward and Reverse Link I/O Signal Descriptions and Timing Relationships
Reverse Link I/O Timing Relationships
Refer to the following four timing diagrams for reverse link. There are two for RC1–2 (Figure 10-18 and
Figure 10-19) and two for RC3–4 (Figure 10-20 and Figure 10-21). These diagrams illustrate the timing
relationships between the signals at the rear panel BNC/SMB output and input connectors. Signal states are
referenced to the chip clock provided at the DATA CLK OUT connector.
Figure 10-18
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Reverse Link I/O Timing Diagram for RC1-2 - Outputs
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Figure 10-19
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Reverse Link I/O Timing Diagram for RC1-2 - Inputs
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Forward and Reverse Link I/O Signal Descriptions and Timing Relationships
Figure 10-20
Chapter 10
Reverse Link I/O Timing Diagram for RC3–4 - Outputs
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Figure 10-21
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Reverse Link I/O Timing Diagram for RC3–4 - Inputs
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Applying a User-Defined FIR Filter to a cdma2000 Waveform
Applying a User-Defined FIR Filter to a cdma2000 Waveform
Custom FIR filters can be created using the FIR table editor feature or they can be created externally and
downloaded into signal generator memory. Once a filter is stored in memory, you can select it for use with a
custom modulation state. This example requires that at least one FIR file already be stored in memory. For
an example of creating and storing a FIR filter, see “Creating a User-Defined FIR Filter Using the FIR Table
Editor” on page 168.
1. Press Preset.
2. Press Mode > CDMA > Arb CDMA2000 > More (1 of 2) > CDMA2000 Define.
3. Press Filter > Select > User FIR.
In this example, there are two FIR files listed: NEWFIR1 and NEWFIR2. (These files were created in the
examples in Chapter 4, “Basic Digital Operation (Option 001/601 or 002/602),” on page 89.)
Figure 10-22
4. Scroll down in the list until NEWFIR2 is highlighted.
5. Press Select File.
The highlighted filter is now selected for use in your custom modulation state, as shown in Figure 10-23
on page 348.
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Figure 10-23
The filter you selected is NEWFIR2. You can see the name displayed below the Select softkey. In the
Filter field, near the left of the display, User FIR is displayed to indicate that a user-defined FIR
filter has been selected.
Once you have set the other modulation parameters to your satisfaction, turn on Custom and the RF
output and your user-defined filter is in use.
NOTE
348
The actual oversample ratio during modulation is automatically selected by the instrument.
A value between 4 and 16 is chosen dependent on the symbol rate, the number of bits per
symbol of the modulation type, and the number of symbols.
Chapter 10
CDMA Digital Modulation (Option 401)
IS-95A Modulation
IS-95A Modulation
This section teaches you how to build dual arbitrary waveform generated IS-95A CDMA modulation for
testing component designs.
Creating a Predefined CDMA State
This section teaches you how to perform the following tasks:
•
“Selecting a Predefined CDMA Setup” on page 349
•
“Generating the Waveform” on page 349
•
“Configuring the RF Output” on page 349
Selecting a Predefined CDMA Setup
1. Press Preset.
2. Press Mode > CDMA > Arb IS-95A.
3. Press Setup Select > 64 Ch Fwd.
Generating the Waveform
Press CDMA Off On.
This generates a predefined 64 channel forward CDMA waveform. The display changes to CDMA Setup:
64 Ch Fwd. During waveform generation, the CDMA and I/Q annunciators appear and the predefined
digital modulation state is stored in volatile ARB memory. The waveform is now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 890.01 MHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off.
The predefined 64 channel forward CDMA signal is now available at the signal generator’s RF OUTPUT
connector.
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IS-95A Modulation
Creating a User-Defined CDMA State
In this procedure, you learn how to customize a predefined CDMA setup, starting with a forward 32 channel
CDMA setup and modifying the setup by adding one channel and changing some of the setup’s default
values.
This section teaches you how to perform the following tasks:
•
“Selecting a CDMA Setup” on page 350
•
“Inserting an Additional Channel” on page 350
•
“Modifying the Walsh Code” on page 350
•
“Modifying the Data” on page 350
•
“Modifying the Code Domain Power” on page 351
•
“Generating the Waveform” on page 351
•
“Configuring the RF Output” on page 351
Selecting a CDMA Setup
1. Press Preset.
2. Press Mode > CDMA > Arb IS-95A.
3. Press Setup Select > 32 Ch Fwd.
Inserting an Additional Channel
1. Press CDMA Define > Edit Channel Setup.
2. Highlight Traffic in the Type column of row 8.
3. Press Insert Row > Traffic > Return.
Modifying the Walsh Code
1. Highlight the Walsh value (38) on table row 8.
2. Press Edit Item > 45 > Enter.
Modifying the Data
1. Highlight the Data value (RANDOM) on table row 8.
2. Press Edit Item > 00001000 > Enter.
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Modifying the Code Domain Power
Press Adjust Code Domain Power > IS-97 Levels.
You now have a custom, forward 33 channel CDMA signal at IS-97 power levels, with an inserted traffic
channel carrying user-defined data at a Walsh code of 45 on table row 8, as shown in the following figure.
Generating the Waveform
Press Return > Return > CDMA Off On.
This generates a waveform with the custom CDMA state created in the previous sections. The display
changes to CDMA Setup: 32 Ch Fwd (Modified). During waveform generation, the CDMA and I/Q
annunciators appear and the predefined digital modulation state is stored in volatile memory. The waveform
is now modulating the RF carrier.
For instructions on storing this custom CDMA state to the non-volatile memory of the signal generator, see
“Storing a Component Test Waveform to Memory” on page 320.
Configuring the RF Output
1. Set the RF output frequency to 890.01 MHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off.
The custom CDMA signal is now available at the RF OUTPUT connector.
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Applying Changes to an Active CDMA State
If the CDMA format is currently in use (CDMA Off On set to On) while changes are made in the CDMA
Channel Setup table editor, you must apply the changes before the updated waveform will be generated.
From the CDMA Channel Setup table editor, press the following keys to apply the changes and generate a
new user-defined CDMA waveform based on the updated values:
Return > Apply Channel Setup.
To store a custom CDMA state file, refer to “Storing a Component Test Waveform to Memory” on page 320.
To recall a custom CDMA state file, refer to “Recalling a Component Test Waveform” on page 321.
Creating a User-Defined Multicarrier CDMA State
In this procedure, you learn how to customize a predefined multicarrier CDMA setup. Rather than building a
4-carrier setup one carrier at a time, you start with a predefined 3-carrier CDMA setup and modify the setup
by adding an additional carrier and changing some of the default values.
This section teaches you how to perform the following tasks:
•
“Selecting a Multicarrier CDMA Setup” on page 352
•
“Adding a Carrier” on page 352
•
“Modifying Carrier Frequency Offset” on page 353
•
“Modifying Carrier Power” on page 353
•
“Generating the Waveform” on page 353
•
“Configuring the RF Output” on page 354
Selecting a Multicarrier CDMA Setup
1. Press Preset.
2. Press Mode > CDMA > Arb IS-95A.
3. Press Multicarrier Off On > Multicarrier Define.
Adding a Carrier
1. Highlight the 9 channel forward carrier in table row 2.
2. Press Insert Row > Pilot > Return.
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Modifying Carrier Frequency Offset
1. Highlight the Freq Offset value (0.00 kHz) for the new pilot carrier in row 3.
2. Press Edit Item > -625 > kHz.
Modifying Carrier Power
1. Highlight the Power value (0.00 dB) for the new pilot carrier in row 3.
2. Press Edit Item > -10 > dB.
You now have a user-defined 4-carrier CDMA waveform with an inserted pilot carrier at a frequency
offset of -625 kHz and a power level of -10.00 dBm, as shown in the following figure.
Generating the Waveform
Press Return > CDMA Off On.
This generates a waveform with the user-defined multicarrier CDMA state created in the previous sections.
The display changes to Multicarrier Setup: 3 Carriers (Modified). During waveform
generation, the CDMA and I/Q annunciators appear and the user-defined multicarrier CDMA state is stored
in volatile memory. The waveform is now modulating the RF carrier.
For instructions on storing this user-defined multicarrier CDMA state to non-volatile memory, see “Storing a
Component Test Waveform to Memory” on page 320.
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Configuring the RF Output
1. Set the RF output frequency to 890.01 MHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off.
The user-defined multicarrier CDMA signal is now available at the RF OUTPUT connector.
Applying Changes to an Active Multicarrier CDMA State
If the CDMA format is currently in use (CDMA Off On set to On) while changes are made in the
Multicarrier CDMA Setup table editor, you must apply the changes before the updated waveform will
be generated.
From the Multicarrier CDMA Setup table editor, press the following keys to apply the changes and
generate a new user-defined multicarrier CDMA waveform based on the updated values:
Return > Apply Multicarrier.
To store a custom multicarrier CDMA state file, refer to, “Storing a Component Test Waveform to Memory”
on page 320.
To recall a custom multicarrier CDMA state file, refer to “Recalling a Component Test Waveform” on
page 321.
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11 GPS Modulation (Option 409)
Option 409 includes real time multiple-satellite and single-satellite global positioning system (GPS) signal
generation capabilities. This feature is available only in E4438C ESG Vector Signal Genreators with Option
001/601 or 002/602. The following list shows the topics covered in this chapter:
•
“Real Time MSGPS” on page 356 (multiple satellite GPS)
•
“Real Time GPS” on page 363 (single satellite GPS)
NOTE
A previous version of Option 409 provided only single satellite (Real Time GPS) capability.
You can upgrade to the new version of Option 409 that includes Real Time MSGPS by
downloading firmware revision C.04.97 to your E4438C.
Single satellite (Real Time GPS) capability in firmware revision C.04.97 is compatible with
the single satellite capability in the previous version of Option 409. (You can use SCPI
programming code written for single satellite setups in the previous version for single
satellite setups in the new version.)
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Real Time MSGPS
Real Time MSGPS
In Real Time MSGPS mode, selectable scenario files define simulated multiple-satellite conditions. The
E4438C generates a signal (C/A code only) simulating multiple satellite transmissions from the information
in the selected scenario file. MSGPS signal generation capabilities include:
•
selectable MSGPS scenario files that include the following information:
—
—
—
—
simulated location (city, latitude, longitude, elevation)
simulated date and time
scenario duration
satellite IDs present (in view) in the scenario
•
pause and resume function for the currently playing scenario
•
restart function that sets the currently playing scenario to the beginning
(without turning off the RF output)
•
adjustable number of satellites in view to include in the generated signal
•
selectable internal or external chip clock reference source
•
adjustable chip clock reference (10.23 Mcps ± 10%)
•
selectable I/Q phase (normal or inverted)
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Signal Generation Block Diagram
Figure 11-1 shows how the signal is generated within the ESG for a four satellite MSGPS simulation. The
ESG produces a simulated signal for each satellite and then sums them together to produce the MSGPS
signal. Use the Number of Satellites softkey to specify the number of satellites in the MSGPS simulation.
Figure 11-1
Chapter 11
MSGPS Signal Generation Diagram
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Scenario Files
When you install option 409, a GPS directory is created in the ESG non-volatile memory and two MSGPS
scenario files are loaded into the GPS directory. Additional scenario files are available for Option 409.
(Go to http://www.agilent.com/find/e4438c and click the Options tab.) After downloading a
scenario file to your PC, you can download the scenario file to the ESG using FTP over a local area network
(LAN) or using SCPI commands over a general purpose interface bus (GPIB) interface.
Downloading Scenario Files Using FTP (LAN)
The following procedure describes how to download scenario files to an ESG using FTP on a PC connected
to your ESG through a LAN:
1. On the PC click Start > Programs > Accessories > Command Prompt.
2. At the command prompt enter: ftp <IP address> or <hostname>
3. At the user name prompt, press Enter.
4. At the password prompt, press Enter. You are now in the signal generator’s user directory.
5. Type cd GPS.
6. Type bin.
7. Type put <scenario_file>.
8. Type quit or bye to end your FTP session.
9. Type exit to end the command prompt session.
Downloading Scenario Files Using SCPI Commands (GPIB)
The following procedure describes how to download scenario files to an ESG using a SCPI command on a
PC connected to your ESG through a GPIB interface:
1. Open your web browser and type in the IP address of your ESG.. The ESG’s Welcome webpage is
displayed.
2. Click Signal Generator Web Control. Below the graphical representation of the ESG front panel is a field
for entering SCPI commands.
3. Enter the following command in the SCPI command field:
:MEMory:DATA "<GPS:file_name>",<data_block>
where file_name is the name of the destination file in ESG memory and GPS: specifies the destination
directory. Refer to the Programming Guide for a description of the <data_block> parameter.
NOTE
358
Refer to the Programming Guide for more information on downloading files.
Chapter 11
GPS Modulation (Option 409)
Real Time MSGPS
RF Power Level Considerations
When you set up your GPS test signal, pay special attention to the RF power level delivered to the GPS
receiver. Because typical GPS sensitivities are between −155 dBm and −159 dBm, delivering a GPS signal
to your device with a power level greater than −150 dBm or less than −160 dBm may produce invalid test
results.
If you use a physical connection to apply the GPS signal to your antenna, keep in mind that most GPS
antennas are active (a DC voltage is delivered to the antenna from the receiver). A DC block is therefore
required between the signal generator and the antenna. For direct connection, Agilent recommends setting
the signal generator RF output power to between −70 and −80 dBm and using an 80 dB attenuator and a DC
blocking device between the signal generator output and the antenna input of the receiver under test.
If you use a radiated connection, place your receiver in a calibrated test fixture designed with a link budget
that will deliver a −150 dBm to −160 dBm power level at the receiver antenna.
Using NMEA data to monitor signal power
One method to monitor the receiver’s perceived signal level is to monitor the National Marine Electronics
Association (NMEA) data stream from the receiver. Most GPS receivers have the capability to output data
via a serial RS232 connection in NMEA format. An NMEA message called GPGSV reports the signal
strength of the satellites that the GPS receiver is tracking. The GPGSV message reports a carrier-to-noise
(CNO) value for each observed satellite. As you monitor this message, increase or decrease the power to the
receiver until the receiver’s perceived CNO values are between 35 and 40. Table 11-1 on page 360 shows
how to obtain the CNO value from the GPGSV message.
The following example is a set of three GPGSV messages. The receiver produces a maximum of three
GPGSV messages every second. The fields are comma-separated; two adjacent commas signify a field for
which a value is not assigned.
$GPGSV,3,1,12,21,71,000,,27,68,000,34,08,62,000,33,29,52,000,,*71
$GPGSV,3,2,12,24,39,000,,10,36,000,,26,35,000,,25,32,000,35*71
$GPGSV,3,3,12,19,29,000,,03,20,000,33,16,19,000,34,18,19,000,*71
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Table 11-1 describes each field for the first of the three GPGSV messages in the example:
$GPGSV,3,1,12,21,71,000,,27,68,000,34,08,62,000,33,29,52,000,,*71
Table 11-1
GPGSV Fields
GPGSV Field
Description
$GPGSV,
3,
Number of GPGSV messages in this set
1,
Number of this GPGSV in the set (1 of 3)
12,
Total number of satellites in view
21,71,000,,
Satellite 21, elevation 71, azimuth 0, CNO unknown
27,68,000,34
Satellite 27, elevation 68, azimuth 0, CNO 34
08,62,000,33,
Satellite 8, elevation 62, azimuth 0, CNO 33
29,52,000,,
Satellite 29, elevation 52, azimuth 0, CNO unknown
*71
Checksum
If no CNO value is reported for a particular satellite (satellites 21 and 29 in the table) the receiver is
currently not tracking that satellite.
For more information, refer to the following document, available at http://www.nmea.org/pub/0183/.
NMEA 0183, Standard For Interfacing Marine Electronic Devices
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Generating a Real Time MSGPS Signal
This procedure uses the internal reference clock with the factory preset settings (the C/A chip rate is 1.023
Mcps with a clock reference of 10.23 Mcps).
Set the carrier frequency and amplitude
1. Press the Preset hardkey.
2. Press the Frequency hardkey. Using the numeric keypad, set the signal generator RF output carrier
frequency to 1.57542 GHz.
3. Press the Amplitude hardkey. Using the numeric keypad, set the signal generator RF output amplitude to
−135 dBm.
4. Press RF On/Off to toggle the RF output on.
Select and play a multi-satellite scenario
1. Press Mode > More (1 of 2) > GPS > Real Time MSGPS.
2. Press Scenario.
3. Use the navigation softkeys or the up and down arrow hardkeys to highlight the santarosa scenario file.
4. Press Select Scenario. A summary of the scenario is displayed including the simulated location, the date
and time, and the satellites in view.
5. Press Number of Satellites and enter 5 to use only the first five satellites in view in the generated signal.
6. Press Real-time MSGPS Off On to On to play the selected scenario.
7. Press Pause. The scenario file stops playing.
8. Press Resume. The scenario file continues playing from the point at which it was paused.
9. Press Restart. The scenario file plays from the beginning without turning off the RF.
NOTE
Selecting a new scenario, toggling Real-time MSGPS off and on, or pressing Restart sets
the active scenario to the beginning. If Resume is active, the scenario immediately starts
playing; if Pause is active, select Resume to start playing the scenario.
Figure 11-2 on page 362 shows the signal generator display with the santarosa MSGPS scenario selected.
The scenario information within the box (Scenario State, Signal Play Duration, Satellites in View) is
dynamic. The scenario information outside of the box ( Location, Start Date, and so on) is static.
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Figure 11-2
Real Time MSGPS Scenario
Configuring the External Reference Clock
1. Connect the external reference clock source to the rear panel connector BASEBAND GEN REF IN.
2. Set the chip rate of the external clock to the desired value.
3. Press Mode > More (1 of 2) > GPS > Real Time MSGPS > More (1 of 2) > GPS Ref Clk Ext Int to Ext.
4. Press GPS Ref (f0).
5. Use the numeric keypad to set the GPS reference clock to the same chip rate as the external clock.
NOTE
362
The chip rate of the external source must match the chip rate of the reference clock set using
the GPS Ref (f0) softkey.
Chapter 11
GPS Modulation (Option 409)
Real Time GPS
Real Time GPS
This real-time personality simulates GPS satellite transmissions for single channel receiver testing. Basic
GPS signal building capabilities include:
•
P code generation at 10.23 Mcps with the standard GPS 10.23 Mcps reference
•
C/A code generation at 1.023 Mcps with the standard GPS 10.23 Mcps reference
•
navigation data output at 50 bps using PN9, PN15, a fixed 4-bit pattern, a user-defined file, or default
data (TLM mode) for encoding with the C/A code or the C/A + P code
•
three selectable ranging codes: C/A, P, or C/A+P
•
satellite ID range of 1 to 32 with an additional range of 33 to 37 for other uses
•
selectable data modes: Raw, Encoded, and TLM
•
simulated doppler shift with a 250 kHz range
•
selectable internal or external chip clock reference source
The signal generator’s pre-defined GPS signal setup includes a C/A ranging code, a satellite ID of 1, zero
doppler shift, a 10.23 Mcps reference clock, and the Raw data mode enabled, using PN9 data.
The satellite ID numbers match the pseudorandom numbers used to generate the C/A and P codes and
dictate the amount of chip delay in compliance with the GPS standards..
The following advanced features are also available:
•
P code power adjustment (−40 to 0 dB)
•
adjustable chip clock reference (1 kcps to 12.5 Mcps)
•
selectable I/Q phase
•
selectable filters and the ability to create user-defined filters
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Real Time GPS Introduction
Signal Generation Block Diagram
Figure 11-3 shows how the GPS signal is generated within the ESG. Notice that the C/A code modulates the
L-band signal using the I axis of the I/Q modulator, and the P code modulates the L-band signal using the Q
axis. Select the data provided by the data generator using the Data softkey or by choosing the TLM data
mode.
Figure 11-3
364
GPS Signal Generation Diagram
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Real Time GPS
Data Modes and Subframe Structures
You can select one of the three following data modes for use with the C/A or C/A+P ranging code:
•
Raw - The Raw data mode enables the continuous transmission of 300 bits of data per subframe without
incorporating parity bits. Use this mode for BER and low-level demodulation testing.
•
Enc - The encoded (Enc) data mode enables the continuous transmission of 10 words per subframe, with
each word containing 24 bits of raw data and 6 trailing parity bits (computed from the selected data by
the ESG).
•
TLM - The telemetry (TLM) mode enables the continuous transmission of a formatted TLM word, a
handover word (HOW), and default navigation data as outlined in the Global Positioning System
Standard Positioning Service Signal Specification, 2nd Edition, June 2, 1995. Use this mode for receiver
testing.
Figure 11-4 shows the subframe structures for each data mode.
Figure 11-4
Chapter 11
Subframe Structures
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The TLM word is 30-bits long, with an 8-bit preamble, 16 reserve bits (bits 9 to 24, all set to zero), and 6
parity bits (bits 25 to 30).
The HOW word is 30-bits long, with the first 17 bits used for an incrementing time-of-week (TOW), bits 23
and 24 used for parity computation, and bits 25 to 30 used for parity bits.
During a GPS signal transmission, a pulse signal is generated every 6 seconds at the
EVENT 1 rear panel connector. This pulse coincides with the beginning of each subframe starting with the
second subframe and is synchronized to the RF output to compensate for any internal signal delay.
Chip Clock Reference
The GPS reference clock (chip clock) is adjustable using the GPS Ref (f0) softkey. The factory-set value is
10.23 Mcps (the GPS standard). You can use the internal chip clock or an external source to provide the
reference. To use an external reference, connect the external source to the DATA CLOCK input connector.
NOTE
If you use an external source to provide the chip clock reference, the frequency of the
external source must match the ESG’s reference clock frequency. Press the GPS Ref (f0)
softkey then use the numeric keypad to enter the reference clock frequency.
The P and C/A code chip rates are determined by the reference clock frequency whether you are using the
internal or an external chip clock reference. The P code chip rate matches the reference clock frequency and
the C/A code chip rate is one-tenth of the reference clock frequency. Refer to Figure 11-3 on page 364 for a
block diagram showing how the GPS signal is generated within the ESG.
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Rear Panel Signal Synchronization
Figure 11-5 illustrates the timing relationships of the GPS signals available at the signal generator rear panel.
The AUX I/O connector outputs the SYMBOL SYNC OUT, DATA CLOCK OUT, and DATA OUT signals
(refer to, “13. AUX I/O Connector” on page 41 for more information). EVENT 1 and EVENT 2 are BNC
connectors. If the signal generator is configured with Option 1EM, EVENT 1 and EVENT 2 connectors are
changed from BNC to SMB connectors. See “Rear Panel Overview” on page 37.
Figure 11-5
Chapter 11
GPS Signals
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User Files
You can create data files internally in the ESG or create them externally and download them to the ESG. In
either case, the size of user data files is limited by the amount of available ESG memory. If you develop data
files externally, you can define signal structures that are not available internally in the ESG. For example, if
you require a fully-coded signal consisting of frames structured according to GPS standards (1 frame
consisting of 5 subframes and 25 pages), you can develop this signal externally and download it to the ESG.
User files can be in either binary or bit format.
Select a data mode for your data file as you would for other data types (see “Data Modes and Subframe
Structures” on page 365). If files are created externally and incorporate parity bits, use the Raw data mode to
transmit the data in its original form. If your file does not contain parity bits and you want to incorporate
parity bits in the transmitted signal, select the encoded (Enc) data mode. The ESG will compute parity bits
for the last 6-bits of each word.
NOTE
If you select the encoded mode for a user file that incorporates parity bits, the parity bits
will be recomputed and their values changed.
Bit Error Rate Test Measurements
Bit error rate test (BERT) measurements require an ESG with Option UN7 (Baseband BERT) or a
customer-supplied, external BER meter. The GPS signal can be configured using either a PN9 or PN15
sequence. To avoid disrupting the sequence, use the Raw data mode so parity bits are not computed for the
subframe.
When you perform BERT measurements using an externally supplied BER meter, the ESG provides the
GPS signal to the unit under test (UUT) and the BER meter computes the error results. If the ESG with
Option UN7 is used, the ESG provides the signal and makes the BERT measurements. When the ESG
performs the BERT measurement, it accepts a clock and gate signal from the UUT as well as the data. If the
UUT cannot provide a data clock signal, the ESG can provide a clock signal from the rear panel Aux I/O
connector (refer to “13. AUX I/O Connector” on page 41). When the clock signal from the ESG is used, add
a delay to the signal equal to the UUT’s processing time.
For information on setting up BERT measurements refer to “Setting Up a GPS Bit Error Rate Test” on page
373.
For detailed information on BERT, refer to “Bit Error Rate Tester–Option UN7” on page 292.
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Setting Up the Real Time GPS Signal
If the signal generator is in the factory-defined preset mode, (Utility > Power On/Preset > Preset Normal User to
Normal) a basic GPS signal is automatically set up when you press the Preset key. Perform step 2 and steps 6
through 8 to generate a signal at the RF OUTPUT connector. To set up a signal using additional features of
the GPS personality, complete this procedure starting with step 1.
1. Press Preset.
2. Press Mode > More (1 of 2) > GPS > Real Time GPS.
3. Press Satellite ID > 8 > Enter.
4. Press Doppler Shift > 2.5 > kHz.
5. Press Data Mode Enc TLM to Enc.
6. Press Data > PN Sequence > PN15.
To create a user file, refer to “Creating a User File” on page 190.
7. Press Real-time GPS Off On to On.
8. Press the Frequency hardkey. Using the numeric keypad, set the signal generator RF output frequency to
1.57542 GHz (L1 carrier frequency).
9. Press the Amplitude hardkey. Using the numeric keypad, set the signal generator RF output amplitude to
−120 dBm.
10. Turn the RF output on by pressing the RF On/Off hardkey on the signal generator front panel.
The real-time GPS signal is now available at the signal generator RF OUTPUT connector. Figure 11-6 on
page 370 shows what the signal generator display should like after all steps have been completed. Notice the
GPS, I/Q, and RF ON annunciators are on and the parameter settings for the signal are displayed in the
status area of the signal generator display.
This procedure sets up a GPS signal that incorporates a subframe structure using 10 words, each with 24 raw
data bits and 6 parity bits computed from the data source. The signal generator created this subframe
structure when you selected Enc as the data mode and a PN15 sequence as the data type. The PN15 sequence
was encoded with the C/A code at 50 bps. Using factory preset settings, the C/A chip rate is 1.023 Mcps
with a clock reference of 10.23 Mcps. A 2.5 kHz doppler shift simulates the relative motion of the satellite
with respect to the receiver. For more information on the GPS option, refer to “Real Time GPS” on page
363.
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Figure 11-6
Real Time GPS Setup with Internal Clock
Configuring the External Reference Clock
1. Access the real-time GPS personality (Mode > More(1 of 2) > GPS > Real Time GPS).
2. Press More (1 of 2) > GPS Ref Clk Ext Int to Ext.
3. Press GPS Ref (f0) > 11.03 > kcps.
4. Connect the external reference clock source to the DATA CLOCK INPUT connector.
The maximum clock rate for this input connector is 50 MHz with a voltage range of
−0.5 to 5.5 V.
5. Set the external reference clock source to the chip rate value entered in Step 3.
The maximum data rate for this input connector is 50 Mb/s with a voltage range of
−0.5 to 5.5 V.
NOTE
The chip rate of the external source must match the chip rate value set using the GPS Ref (f0)
softkey.
Figure 11-7 on page 371 shows what the signal generator display should look like after all the steps have
been completed. The CA Chip Rate, P Chip Rate, GPS Ref (f0), and GPS Ref Clk fields in the
status area of the display show the new parameters you set in this procedure. Notice the settings Satellite
ID, Doppler Shift, Data, and Data Mode, have not changed from the previous procedure, “Setting Up
the Real Time GPS Signal” on page 369.
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Figure 11-7
Real Time GPS Setup with External Clock
This procedure used an external source as the reference clock signal. The reference frequency was changed
from the GPS standard of 10.23 Mcps to 11.03 kcps. This change in the reference signal frequency
automatically changed the P and C/A code chip rates. Since the P code chip rate matches the reference
frequency, its chip rate is now 11.03 kcps; the C/A code rate is one-tenth of the reference frequency and so is
now 1.103 kcps. For more information on the GPS option, refer to “Real Time GPS” on page 363.
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Testing Receiver Sensitivity
Refer to Figure 11-8.
1. Connect the cables between the receiver and the ESG as shown in Figure 11-8.
Figure 11-8
Setup for a Receiver Sensitivity Test
2. Set the GPS data mode to TLM.
3. Set the power level on the ESG.
4. Set the L-band frequency on the ESG.
5. Set up the UE (user equipment) to receive the signal from the ESG.
6. Turn on the GPS personality and the RF output on the ESG.
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Setting Up a GPS Bit Error Rate Test
This section shows how to make GPS BER measurements using the ESG Signal Generator with
Option UN7.
The following procedures explain how to set up the ESG for making BER measurements:
•
“Connecting the Test Equipment” on page 374
•
“Setting the Carrier Frequency and Power Level” on page 374
•
“Selecting the Data Format” on page 375
•
“Setting Up the GPS Receiver” on page 375
•
“Selecting the BERT Data Pattern and Total Bits” on page 375
•
“Selecting the BERT Trigger” on page 376
•
“Starting BERT measurements” on page 376
Required Equipment
The following equipment is required to make BER measurements.
•
ESG Signal Generator, model E4438C with Options 001/601or 002/602, 409, and UN7
•
an external controller to control the receiver under test
•
a 20dB attenuator
•
a level-matching circuit between the receiver under test and the signal generator when the receiver signal
specifications are different from those of the signal generator
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GPS Modulation (Option 409)
Real Time GPS
Connecting the Test Equipment
1. Connect the cables between your receiver and the ESG as shown in Figure 11-9:
Figure 11-9
Setup for a GPS Bit Error Rate Test
Setting the Carrier Frequency and Power Level
1. Press the Preset hardkey.
2. Press the Frequency hardkey. Using the numeric keypad, set the signal generator RF output carrier
frequency to 1.57542 GHz.
3. Press the Amplitude hardkey. Using the numeric keypad, set the signal generator RF output amplitude to
−135 dBm.
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Real Time GPS
Selecting the Data Format
1. Press Mode > More (1 or 2) > GPS > Real Time GPS.
2. Ensure that Raw is the selected data mode.
If Raw is not the current data mode, press Data Mode Raw Enc TLM to Raw.
3. Ensure that PN9 is the selected data sequence.
If PN9 is not the current data sequence, press Data > PN Sequence > PN9.
4. Press Real-time GPS Off On to On.
5. Press RF On/Off to toggle the RF output on.
The modulated signal is now available at the RF OUTPUT connector. Notice that the display annunciators
for GPS and I/Q are on and the display annunciator RF OFF has changed to RF ON.
Setting Up the GPS Receiver
Setup the GPS receiver to accept the carrier frequency and output the data and clock signal used for the bit
error rate measurements.
Selecting the BERT Data Pattern and Total Bits
1. Access the BERT function.
For an ESG with Option UN7 Installed
Press Aux Fctn > BERT > Configure BERT.
For an ESG with Options UN7 and 300 Installed
Press Aux Fctn > BERT > Baseband BERT > Configure BERT.
If the Data softkey does not show that PN9 is the selected data pattern, press
Data > PN9.
The selected PN sequence must match the data PN sequence used on the channel being measured. For
example if the DCH (DTCH) is using PN9 data, then the data selection in the BERT function must also
be PN9.
2. Press Total Bits > 1000 > Bits.
1000 bits at 50 bps takes 20 seconds to test.
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GPS Modulation (Option 409)
Real Time GPS
Selecting the BERT Trigger
1. Press Return > Configure Trigger.
If the BERT Trigger softkey does not show Trigger Key as the selected trigger, press
BERT Trigger > Trigger Key.
2. Press Return > BERT Off On to On.
Starting BERT measurements
Press the front panel Trigger hardkey to start the BER measurement. You will see the measurement result
values of the Total Bits, Error Bits, and BER on the signal generator display.
NOTE
If you encounter problems making a BER measurement, check the following:
•
Confirm that the cables are properly connected.
•
Confirm that the data pattern for the BER measurement, specified by the Data softkey,
matches the data pattern of the receiver under test.
•
Confirm that the data mode selected for the BER measurement is Raw.
•
Confirm that the RF is turned on.
•
Make sure that the amplitude is set to the correct level.
•
Confirm that the receiver under test is controlled to receive the signal of the specified
carrier frequency.
•
376
Confirm that the chip rate of the external source matches the chip rate set using the
GPS Ref (f0) softkey.
Chapter 11
12 Multitone Waveform Generator (Options 001/601
or 002/602)
The following list shows the topics covered in this chapter.
•
“Creating a Custom Multitone Waveform” on page 378
•
“Applying Changes to an Active Multitone Signal” on page 380
377
Multitone Waveform Generator (Options 001/601 or 002/602)
Creating a Custom Multitone Waveform
Creating a Custom Multitone Waveform
Using the Multitone Setup table editor, you can define, modify and store user-defined multitone
waveforms. Multitone waveforms are generated by the dual arbitrary waveform generator.
This section teaches you how to perform the following tasks:
•
“Initializing the Multitone Setup Table Editor” on page 378
•
“Configuring Tone Powers and Tone Phases” on page 378
•
“Removing a Tone” on page 378
•
“Generating the Waveform” on page 379
•
“Configuring the RF Output” on page 379
Initializing the Multitone Setup Table Editor
1. Press Preset.
2. Press Mode > More (1 of 2) > Multitone
3. Press Initialize Table > Number of Tones > 5 > Enter.
4. Press Freq Spacing > 20 > kHz.
5. Press Done.
You now have a multitone setup with five tones spaced 20 kHz apart. The center tone is placed at the carrier
frequency, while the other four tones are spaced in 20 kHz increments from the center tone.
Configuring Tone Powers and Tone Phases
1. Highlight the value (0 dB) in the Power column for the tone in row 2.
2. Press Edit Item > -4.5 > dB.
3. Highlight the value (0) in the Phase column for the tone in row 2.
4. Press Edit Item > 123 > deg.
Removing a Tone
1. Highlight the value (On) in the State column for the tone in row 4.
2. Press Toggle State.
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Creating a Custom Multitone Waveform
Generating the Waveform
Press Multitone Off On until On is highlighted.
This generates the multitone waveform with the parameters defined in the previous sections. During
waveform generation, the M-TONE and I/Q annunciators activate and the multitone waveform is stored in
volatile ARB memory. The waveform is now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 100 MHz.
2. Set the output amplitude to 0 dBm.
3. Press RF On/Off.
The multitone waveform is now available at the signal generator’s RF OUTPUT connector.
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Multitone Waveform Generator (Options 001/601 or 002/602)
Applying Changes to an Active Multitone Signal
Applying Changes to an Active Multitone Signal
If the multitone generator is currently in use (Multitone Off On set to On) while changes are made in the
Multitone Setup table editor, you must apply the changes before the updated waveform will be
generated.
From the Multitone Setup table editor, press the following key to apply the changes and generate a
multitone waveform based on the updated values:
Apply Multitone
Storing a Multitone Waveform
In this example, you learn how to store a multitone waveform. If you have not created a multitone
waveform, complete the steps in the previous section, “Creating a Custom Multitone Waveform” on
page 378.
1. Press More (1 of 2) > Load/Store > Store To File.
If there is already a file name from the Catalog of MTONE Files occupying the active entry
area, press the following keys:
Edit Keys > Clear Text
2. Enter a file name (for example, 5TONE) using the alpha keys and the numeric keypad with a maximum
length of 23 characters.
3. Press Enter.
The multitone waveform is now stored in the Catalog of MTONE Files.
NOTE
380
The RF output amplitude, frequency, and operating state settings are not stored as part of a
multitone waveform file.
Chapter 12
Multitone Waveform Generator (Options 001/601 or 002/602)
Applying Changes to an Active Multitone Signal
Recalling a Multitone Waveform
Using this procedure, you learn how to recall a multitone waveform from the signal generator’s memory
catalog.
If you have not created and stored a multitone waveform, complete the steps in the previous sections,
“Creating a Custom Multitone Waveform” on page 378 and “Storing a Multitone Waveform” on page 380,
then preset the signal generator to clear the stored multitone waveform from volatile ARB memory.
1. Press Mode > Multitone.
2. Press More (1 of 2) > Load/Store.
3. Highlight the desired file (for example, 5TONE).
4. Press Load From Selected File > Confirm Load From File.
5. Press More (2of 2) > Multitone Off On until On is highlighted.
The firmware generates the multitone waveform in ARB memory. After waveform generation, the multitone
waveform is available to be modulated on the RF output.
For instruction on configuring the RF output, see “Configuring the RF Output” on page 379.
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Applying Changes to an Active Multitone Signal
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Chapter 12
13 Custom Digital Modulation (Options 001/601 or
002/602)
The following list shows the topics covered in this chapter:
•
“Using the Arbitrary Waveform Generator” on page 384
•
“Using the Real Time I/Q Baseband Generator” on page 390
383
Custom Digital Modulation (Options 001/601 or 002/602)
Using the Arbitrary Waveform Generator
Using the Arbitrary Waveform Generator
This section teaches you how to build dual arbitrary (ARB) waveform generated custom TDMA digital
modulation for testing component designs.
Custom ARB digital modulation creates waveforms using modulation types, filtering, symbol rates, and
other parameters defined by digital communications standards. These waveforms are formatted as unframed
data.
Using Predefined Custom TDMA Digital Modulation
This section teaches you how to perform the following tasks:
•
“Selecting a Predefined EDGE Setup” on page 384
•
“Generating the Waveform” on page 384
•
“Configuring the RF Output” on page 384
Selecting a Predefined EDGE Setup
1. Press Preset.
2. Press Mode > Custom > ARB Waveform Generator.
3. Press Setup Select > EDGE.
Generating the Waveform
Press Digital Modulation Off On.
This generates a waveform with the pre-defined EDGE state selected in the previous section. The display
changes to Dig Mod Setup: EDGE. During waveform generation, the DIGMOD and I/Q annunciators
appear and the pre-defined digital modulation state is stored in volatile memory (WFM1). The waveform is
now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 891 MHz.
2. Set the output amplitude to −5 dBm.
3. Press RF On/Off.
The predefined EDGE signal is now available at the signal generator’s RF OUTPUT connector.
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Using the Arbitrary Waveform Generator
Creating a Custom TDMA Digital Modulation State
In this procedure, you learn how to set up a single-carrier NADC digital modulation with customized
modulation type, symbol rate, and filtering.
This section teaches you how to perform the following tasks:
•
“Selecting a Digital Modulation Setup” on page 385
•
“Modifying the Modulation Type and Symbol Rate” on page 385
•
“Modifying the Filter” on page 385
•
“Configuring the RF Output” on page 386
Selecting a Digital Modulation Setup
1. Press Preset.
2. Press Mode > Custom > ARB Waveform Generator.
3. Press Setup Select > NADC.
Modifying the Modulation Type and Symbol Rate
1. Press Digital Mod Define > Modulation Type > PSK > QPSK and OQPSK > QPSK.
2. Press Symbol Rate > 56 > ksps.
Modifying the Filter
1. Press Filter > Select > Nyquist.
2. Press Return > Return.
Generating the Waveform
Press Digital Modulation Off On.
This generates a waveform with the custom single-carrier NADC digital modulation state created in the
previous sections. The display changes to Dig Mod Setup: NADC (Modified). During waveform
generation, the DIGMOD and I/Q annunciators appear and the custom single-carrier digital modulation state
is stored in volatile memory. The waveform is now modulating the RF carrier.
For instructions on storing this custom single-carrier NADC digital modulation state to non-volatile memory
catalog, see “Storing a Custom TDMA Digital Modulation State” on page 386.
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Using the Arbitrary Waveform Generator
Configuring the RF Output
1. Set the RF output frequency to 835 MHz.
2. Set the output amplitude to 0 dBm.
3. Press RF On/Off.
The user-defined NADC signal is now available at the RF OUTPUT connector.
Storing a Custom TDMA Digital Modulation State
Using this procedure, you learn how to store a custom digital modulation state and a custom multicarrier
digital modulation state to non-volatile memory.
If you have not created a custom single-carrier digital modulation state, complete the steps in the previous
section, “Creating a Custom TDMA Digital Modulation State” on page 385.
1. Return to the top-level Digital Modulation menu, where Digital Modulation Off On is the first softkey.
2. Press Digital Mod Define > Store Custom Dig Mod State > Store To File.
If there is already a file name from the Catalog of DMOD Files occupying the active entry
area, press the following keys:
Edit Keys > Clear Text
3. Enter a file name (for example, NADCQPSK) using the alpha keys and the numeric keypad with a
maximum length of 23 characters.
4. Press Enter.
The user-defined single-carrier digital modulation state is now stored in non-volatile memory.
NOTE
The RF output amplitude, frequency, and operating state settings are not stored as part of a
user-defined digital modulation state file.
Recalling a Custom TDMA Digital Modulation State
Using this procedure, you learn how to recall a custom digital modulation state from signal non-volatile
memory.
If you have not created and stored a user-defined single-carrier digital modulation state, complete the steps
in the previous sections, “Creating a Custom TDMA Digital Modulation State” on page 385 and “Storing a
Custom TDMA Digital Modulation State” on page 386, then preset the signal generator to clear the stored
user-defined digital modulation waveform from volatile ARB memory.
1. Press Mode > Custom > ARB Waveform Generator.
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Using the Arbitrary Waveform Generator
2. Press Setup Select > More (1 of 2) > Custom Digital Mod State.
3. Highlight the desired file (for example, NADCQPSK).
4. Press Select File.
5. Press Digital Modulation Off On until On is highlighted.
The firmware generates the custom digital modulation waveform in volatile memory. After waveform
generation, the custom digital modulation waveform is available to be modulated on the RF output.
For instruction on configuring the RF output, see “Configuring the RF Output” on page 386.
Creating a Custom Multicarrier TDMA Digital Modulation State
In this procedure, you learn how to customize a predefined multicarrier digital modulation setup by creating
a custom 3-carrier EDGE digital modulation state.
This section teaches you how to perform the following tasks:
•
“Creating a Multicarrier Digital Modulation Setup” on page 387
•
“Modifying Carrier Frequency Offset” on page 387
•
“Modifying Carrier Power” on page 388
•
“Generating the Waveform” on page 384
•
“Configuring the RF Output” on page 388
Creating a Multicarrier Digital Modulation Setup
1. Press Preset.
2. Press Mode > Custom > Arb Waveform Generator.
3. Press Multicarrier Off On.
4. Press Multicarrier Define > Initialize Table > Carrier Setup > EDGE > Done.
Modifying Carrier Frequency Offset
1. Highlight the Freq Offset value (500.000 kHz) for the carrier in row 2.
2. Press Edit Item > -625 > kHz.
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Using the Arbitrary Waveform Generator
Modifying Carrier Power
1. Highlight the Power value (0.00 dB) for the carrier in row 2.
2. Press Edit Item > -10 > dB.
You now have a custom 2-carrier EDGE waveform with a carrier at a frequency offset of −625 kHz and
a power level of −10.00 dBm, as shown in the following figure.
Generating the Waveform
Press Return > Digital Modulation Off On.
This generates a waveform with the custom multicarrier EDGE state created in the previous sections. The
display changes to Dig Mod Setup: Multicarrier (Modified). During waveform generation, the
DIGMOD and I/Q annunciators appear and the new custom multicarrier EDGE state is stored in volatile
memory. The waveform is now modulating the RF carrier.
For instructions on storing this custom multicarrier EDGE state to non-volatile memory, see “Storing a
Custom Multicarrier TDMA Digital Modulation State” on page 389.
Configuring the RF Output
1.
Set the RF output frequency to 890.01 MHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off.
The custom multicarrier EDGE signal is now available at the RF OUTPUT connector.
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Using the Arbitrary Waveform Generator
Storing a Custom Multicarrier TDMA Digital Modulation State
Using this procedure, you learn how to store a custom multicarrier TDMA digital modulation state to
non-volatile memory.
If you have not created a custom multicarrier digital modulation state, complete the steps in the previous
section, “Creating a Custom Multicarrier TDMA Digital Modulation State” on page 387.
1. Return to the top-level Digital Modulation menu, where Digital Modulation Off On is the first softkey.
2. Press Multicarrier Define > More (1 of 2) > Load/ Store > Store To File.
If there is already a file name from the Catalog of MDMOD Files occupying the active entry
area, press the following keys:
Edit Keys > Clear Text
3. Enter a file name (for example, EDGEM1) using the alpha keys and the numeric keypad with a maximum
length of 23 characters.
4. Press Enter.
The user-defined multicarrier digital modulation state is now stored in non-volatile memory.
NOTE
The RF output amplitude, frequency, and operating state settings are not stored as part of a
user-defined digital modulation state file.
Applying Changes to an Active Multicarrier TDMA Digital Modulation State
If the digital modulation format is currently in use (Digital Modulation Off On set to On) while changes are
made in the Multicarrier Setup table editor, you must apply the changes before the updated waveform
will be generated.
From the Multicarrier Setup table editor, press Apply Multicarrier to apply the changes and generate a
new custom multicarrier digital modulation waveform based on the updated values.
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Custom Digital Modulation (Options 001/601 or 002/602)
Using the Real Time I/Q Baseband Generator
Using the Real Time I/Q Baseband Generator
The custom real-time format enables you to create unframed digital modulation with user-defined data,
filtering, symbol rate, modulation type, burst shape, differential data encoding, and other format parameters.
You can choose a predefined mode where filtering, symbol rate and modulation type are defined by the
digital modulation standard, or a user-defined custom modulation.
Selecting Predefined Custom Modulation Modes
1. Press Preset.
2. Press Mode > Custom > Real Time I/Q Base Band.
3. Press More (1 of 3) > More (2 of 3) > Predefined Mode > APCO 25 w/C4FM.
4. Press More (3 of 3).
This selects a predefined mode where filtering, symbol rate and modulation type are defined by the
APCO 25 w/C4FM digital modulation standard and returns you to the top-level custom modulation
menu. To configure data, burst shape, and differential data encoding parameters, see the next section,
“Creating User-Defined Custom Modulation.”
To output this predefined custom modulation, complete the steps in “Generating the Waveform” on
page 392 and “Configuring the RF Output” on page 392.
NOTE
To deselect a predefined mode, press the following keys:
Mode > Custom > Real Time I/Q Base Band > More (1 of 3) > More (2 of 3) > Predefined Mode >
None
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Using the Real Time I/Q Baseband Generator
Creating User-Defined Custom Modulation
This section teaches you how to perform the following tasks:
•
“Selecting Data” on page 391
•
“Configuring the Filter” on page 391
•
“Selecting a Symbol Rate” on page 391
•
“Selecting the Modulation Type” on page 391
•
“Configuring the Burst Rise and Fall Parameters” on page 392
•
“Activating Differential Data Encoding” on page 392
•
“Generating the Waveform” on page 392
•
“Configuring the RF Output” on page 392
Selecting Data
1. Press Preset.
2. Press Mode > Custom > Real Time I/Q Base Band > Data > FIX4.
3. Press 1010 > Enter > Return.
Configuring the Filter
1. Press Filter > Select > Gaussian.
2. Press Filter BbT.
3. Press .45 > Enter > Return.
Selecting a Symbol Rate
1. Press Symbol Rate.
2. Press 25 > ksps > Return.
Selecting the Modulation Type
Press Modulation Type > Select > QAM > 32QAM > Return.
For information on user-defined I/Q mapping, see “User-Defined I/Q Maps” on page 183. For information
on user-defined FSK modulation, see “User-Defined FSK Modulation” on page 187.
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Using the Real Time I/Q Baseband Generator
Configuring the Burst Rise and Fall Parameters
1. Press Burst Shape > Rise Time.
2. Press 5.202 > bits.
3. Press Rise Delay > .667 > bits.
4. Press Fall Time > 4.8 > bits.
5. Press Fall Delay > .667 > bits.
This configures the burst shape for the custom real-time I/Q baseband digital modulation format. For
instructions on creating and applying user-defined burst shape curves, see “Using Customized Burst Shape
Curves” on page 161.
Activating Differential Data Encoding
Press Return.
Press More (1 of 3) > Diff Data Encode Off On.
This activates differential data encoding for the current real-time I/Q baseband digital modulation format.
For more information, see “Differential Encoding” on page 175.
To generate and output the custom digital modulation, complete the steps in the following sections.
Generating the Waveform
Press More (2 of 3) > More (3 of 3)
Press Custom Off On until On is highlighted.
This generates the custom real-time I/Q baseband waveform with the parameters defined in the previous
sections. During waveform generation, the CUSTOM and I/Q annunciators activate and the custom
waveform is stored in pattern RAM. The waveform is now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 500 MHz.
2. Set the output amplitude to 0 dBm.
3. Press RF On/Off.
The custom real-time I/Q baseband waveform is now available at the signal generator’s
RF OUTPUT connector.
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14 Real Time TDMA Formats (Option 402)
In the following sections, this chapter provides the following information. This option is only available in
E4438C ESG Vector Signal Generators with Option 001/601or 002/602.
This chapter contains procedures on operating the real-time TDMA formats. The ESG generates the
modulation for these formats using the ESG’s internal baseband generator. The following list shows the
topcs covered in this chapter:
•
“EDGE Framed Modulation” on page 394
•
“GSM Framed Modulation” on page 398
•
“Enhanced Observed Time Difference (E-OTD)” on page 400
•
“DECT Framed Modulation” on page 413
•
“PHS Framed Modulation” on page 415
•
“PDC Framed Modulation” on page 417
•
“NADC Framed Modulation” on page 419
•
“TETRA Framed Modulation” on page 421
393
Real Time TDMA Formats (Option 402)
EDGE Framed Modulation
EDGE Framed Modulation
This section describes how to build framed, real-time I/Q baseband generated EDGE and GMSK
modulation for testing receiver designs. Each timeslot provides the flexibility of changing from the current
modulation type to a GMSK modulation. The GMSK timeslot selection provides a normal GSM timelsot.
The procedures in this section build on each other, so perform them sequentially.
For optimizing signal integrity when using EDGE and GMSK timeslots together, use the 3GPP standard
settings supported by the ESG for the EDGE timeslots. Modifying the standard settings can affect the proper
operation of the combined timeslots. For example, changing the EDGE filter can cause undesirable frame
alignment. While you can change the EDGE modulation type when you have both EDGE and GMSK
timeslots, changing the modulation type does not change the GMSK timeslot modulation.
NOTE
When using EDGE and GMSK, or multiframe EDGE, limit the symbol rate to no more than
271 ksps. Although higher rates may work, they are not supported.
To build only a GSM signal, see “GSM Framed Modulation” on page 398.
Understanding External Data Connections
NOTE
The external data selection is not a choice for a GMSK timeslot. When GMSK timeslots are
part of the signal, the Ext data selection for EDGE timeslots is unavailable.
The ESG provides various timeslot data selections. One of these selections, the Ext softkey, provides the
capability to use an external data signal connected to the front panel DATA connector. There are two ways to
time the external data, by a bit clock or a symbol synchronization signal. Select the timing option with the
Ext Data Clock Normal Symbol softkey.
The Normal choice notifies the ESG that the data timing is done at the bit level using an external data clock.
Connect the data clock signal to the front panel BNC connector labeled DATA CLOCK. In addition to the
data clock timing signal, connect a single or continuous pulsed symbol synchronization signal to the front
panel BNC connector labeled SYMBOL SYNC. The symbol synchronization signal aligns the first symbol
in the transmission.
The Symbol choice notifies the ESG that the data timing is done at the symbol level using an external
symbol synchronization signal. Connect a continuous pulsed synchronization signal to the front panel BNC
connector labeled SYMBOL SYNC. There is no data clock connection.
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EDGE Framed Modulation
Activating Framed Data Format
1. Press Preset.
2. Press Mode > Real Time TDMA > EDGE > Data Format Pattern Framed.
Configuring the EDGE Timeslots
1. Press Configure Timeslots > Timeslot Type > Custom.
2. Press Configure Custom > Data > FIX4.
3. Press 1010 > Enter > Return > Return.
4. Press Timeslot # > 1 > Enter.
5. Press Configure Timeslots > Timeslot Type > Normal.
6. Press Configure Normal > TS > TSC1 > Return.
7. Press Timeslot Off On to On.
Configuring timeslot zero did not require a timeslot selection, because timeslot zero is the factory preset
timeslot selection. This is shown in step one where the timeslot type selection happened without first
selecting the timeslot number. Notice that a data selection (FIX4) was made for timeslot zero, but that none
was made for timeslot one. This means that timeslot one will use the default data selection of PN9.
Configuring GMSK Timeslots
1. Press Timeslot # > 2 > Enter.
2. Press Timeslot Type > GMSK.
3. Press Configure GMSK > E > PN Sequence > PN15.
4. Press TS > TSC2 > Return.
5. Press Timeslot Off On to On.
6. Press Timeslot # > 3 > Enter.
7. Press Timeslot Type > GMSK.
8. Press Configure GMSK > E > Other Patterns > 32 1’s & 32 0’s.
9. Press TS > TSC4 > Return.
10. Press Timeslot Off On to On.
The GMSK timeslot selection provides a normal GSM timelsot. This is the same normal timeslot found in
the GSM modulation format.
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Real Time TDMA Formats (Option 402)
EDGE Framed Modulation
Disabling Timeslot Ramping
1. Press Timeslot # > 2 > Enter.
2. Press Multislot Off On to On.
3. Press Return.
Turning multislot on disables ramping between the current and the next higher numbered (adjacent)
timeslot. A line underscores the timeslots where ramping is disabled. For this procedure, ramping will not
occur between timeslots two and three (GMSK timeslots). The multislot choice is a setting for each timeslot.
NOTE
Disabling ramping between EDGE and GMSK timeslots produces spectral components that
may not be desired. This is due to the transition between the two modulation types without
ramping.
Generating the Baseband Signal
Press EDGE Off On to On.
This generates an EDGE signal with an active custom timeslot, an active normal timeslot, and two active
GMSK modulated timeslots. While the ESG builds the signal, a status bar appears on the display. After the
signal building process, the EDGE, ENVLP, and I/Q annunciators appear, indicating that the signal is
modulating the RF carrier.
Configuring the RF Output
1. Press Frequency > 891 > MHz.
2. Press Amplitude > –5 > dBm.
3. Press RF On/Off to On.
The user-defined EDGE signal is now available at the signal generator’s RF OUTPUT connector.
To store this real-time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real-time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
Adjusting the Power Level Between Timeslots
1. Press Amplitude > More (1 of 2) > Alternate Amplitude > Alt Amp Delta > –15 > dB.
2. Press Mode Setup > Configure Timeslots > Timeslot # > 1 > Enter.
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EDGE Framed Modulation
3. Press Timeslot Ampl Main Delta to Delta.
The power level for timeslot one is now 15 dB lower than the other active timeslots. To return the timeslot
one to its previous power level, select Main on the Timeslot Ampl Main Delta softkey. The delta amplitude
choice is available for each timeslot, however all timeslots use the same delta value set in the Alternate
Amplitude softkey menu.
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Real Time TDMA Formats (Option 402)
GSM Framed Modulation
GSM Framed Modulation
This section describes how to build framed, real-time I/Q baseband generated GSM modulation for testing
receiver designs. The procedures in this section build on each other, so perform them sequentially.
NOTE
When using multiframe, limit the symbol rate to no more than 271 ksps. Although higher
rates may work, they are not supported.
To build and EDGE and GMSK modulated signal, see “EDGE Framed Modulation” on page 394.
Activating Framed Data Format
1. Press Preset.
2. Press Mode > Real Time TDMA > GSM > Data Format Pattern Framed.
Configuring the First Timeslot
1. Press Configure Timeslots > Timeslot Type > Access.
2. Press Configure Access > E > FIX4.
3. Press 1010 > Enter > Return > Return.
Configuring the Second Timeslot
1. Press Timeslot # > 1 > Enter.
2. Press Timeslot Type > Custom.
3. Press Configure Custom > Other Patterns > 8 1’s & 8 0’s.
4. Press Timeslot Off On to On > Return.
Configuring the Third Timeslot
1. Press Timeslot # > 2 > Enter.
2. Press Timeslot Type > Normal.
3. Press Configure Normal > E > PN Sequence > PN15.
4. Press Timeslot Off On to On > Return.
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Disabling Timeslot Ramping
1. Press Timeslot # > 1 > Enter.
2. Press Multislot Off On to On.
3. Press Return.
Turning multislot on disables ramping between the current and the next higher numbered (adjacent)
timeslot. A line underscores the timeslots where ramping is disabled. For this procedure, ramping will not
occur between timeslots one and two. The multislot choice is a setting for each timeslot.
Generating the Baseband Signal
Press GSM Off On to On.
This generates a GSM signal with an active access timeslot, an active custom timeslot, and an active normal
timeslot. The signal generator may require several seconds to build the signal. During this time, Baseband
Reconfiguring appears on the display. After the reconfiguration is complete, the display reads GSM On
and the GSM, ENVLP, and I/Q annunciators appear indicating that the signal is modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 891 MHz.
2. Set the output amplitude to −5 dBm.
3. Press RF On/Off to On.
The user-defined GSM signal is now available at the signal generator’s RF OUTPUT connector.
To store this real-time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real-time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
Adjusting the Power Level Between Timeslots
1. Press Amplitude > More (1 of 2) > Alternate Amplitude > Alt Amp Delta > –15 > dB.
2. Press Mode Setup > Configure Timeslots > Timeslot # > 1 > Enter.
3. Press Timeslot Ampl Main Delta to Delta.
The power level for timeslot one is now 15 dB lower than the other active timeslots. Selecting Main on the
Timeslot Ampl Main Delta softkey returns the timeslot to its previous power level. The delta amplitude choice
is available for each timeslot, however all timeslots use the same delta value set in the Alternate Amplitude
softkey menu.
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Enhanced Observed Time Difference (E-OTD)
Overview
The Enhanced Observed Timing Difference (E-OTD) positioning method relies upon measuring the time at
which signals from the Base Transceiver Station (BTS) arrive at two geographically dispersed locations–the
mobile phone/station (MS) and a fixed measuring point known as the Location Measurement Unit (LMU)
whose location is known. The position of the MS is determined by comparing the time differences between
the two sets of timing measurements.
Multiple ESGs are used with a remote interface to provide mobile manufactures the ability to test handsets
equipped with the E-OTD feature. The system will simulate a real world network complete with a serving
cell (Agilent E5515C (8960 Series 10) Wireless Communications Test Set) and neighboring cells (ESG
Vector Signal Generator) that can be used to test E-OTD equipped handsets.
The ESG has no front panel user interface for the E-OTD feature, so signal setup is done using the GPIB
interface.
Basic GSM Frame Structure
TDMA Time Slot
A TDMA frame is composed of eight 577 micro second time slots (0–7). The basic TDMA frame duration is
4.615 msec. Each time slot contains 148 bits of information and contains a guard period of 8.25 bits. This
guard period is provided for the mobile station transmission to be attenuated between bursts as defined in the
3GPP standard. Of the 148 bits, some are used to carry data, others are used for control and synchronization.
Refer to Figure 14-1 on page 401.
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Figure 14-1
1 TDMA Frame Structure
Each time slot when transmitted by the base transceiver station (BTS) or mobile phone station (MS) is a
radio burst. There are four types of GSM RF burst. Three of these burst types are in a category called full
duration and the fourth type is a short time duration burst. The three full duration bursts are: normal,
frequency correction, and synchronization. Both the base station and mobile station use the normal burst.
The remaining two sub-types, frequency correction and synchronization, are used only by the base station,
and only transmitted on the first time slot (labeled zero). The forth type is a short burst (88 bits) called the
random access burst (RACH) and only used by the mobile station to make connection with the base station.
The remaining time is padded with guard bits to keep the timing of a slot consistent.
The frame structure for the base station and mobile station are the same. However, the slot numbers are
intentionally offset by three time slots so the mobile station does not have to transmit and receive at the same
time. Refer to Figure 14-1 on page 401.
GSM Multiframe Structure
The TDMA frames are grouped into larger structures called multiframes. These multiframe structures are
necessary to allow the partitioning of physical channels into logical channels.
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26 Frame Multiframe
The most basic of GSM multiframes is the traffic channel multiframe. This is made up of 26 frames and has
a time interval of 120 msec. Each frame of the 26-frame multiframe has an eight time slot TDMA frame
(4.62 msec). The first 12 frames are used to transmit traffic data. Then one frame is used by the Slow
Associated Control Channel (SACCH) which provides channel maintenance. Then another 12 frames of
traffic data followed by an IDLE frame where not data is sent. This IDLE frame allows the mobile station to
perform other tasks such as measuring the signal strength of other neighboring cells. Refer to Figure 14-2 on
page 403.
51 Frame Multiframe
The 51-frame multiframe is comprised of 51 TDMA frames and has a duration of 235.4 ms. This multiframe
is used for control channels. Control channels always occur on the master frequency in the downlink
direction from the BTS to the mobile station. Different formats exist for the makeup of the 51-frame
multiframe but for E-OTD, type IV and V are used. The common features of these channels are the
frequency correction burst (FCCH), the synchronization burst (SCH), and the broadcast control channel
(BCCH). These different channel types allow the mobile station to synchronize to the base station in the
frequency domain and the time domain and provide information about the current broadcast channel. Refer
to Figure 14-2 on page 403.
Superframe
A superframe is composed of 51 26-frame multiframe or 26 51-frame multiframes which is equal to 1326
frames which is the lowest common denominator and is the least number of frames that can absorb the
contents of all the 26 or 51 multiframes and finish with no spare timeslots. Refer to Figure 14-2 on page 403.
Hyperframe
The time interval of the hyperframe is over three hours long which is much longer than the typical telephone
connection. The encryption process used is not likely to repeat itself during a call of reasonable length and
the privacy is not compromised. The hyperframe is made up of 2048 superframes. Refer to Figure 14-2 on
page 403.
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Figure 14-2
Multiframe Hierarchy
Broadcast Channel (BCH)
In a broadcast channel a 51-frame multiframe is transmitted on time slot zero and provides the mobile
station with system information which the mobile station needs to gain access to the network. The broadcast
channel needs to remain at a constant power so other mobile stations can distinguish the broadcast channels
from normal channels. Therefore all eight time slots need to be used during each TDMA frame.
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Non-combined Broadcast Channel
The broadcast channel can be used in two different modes. The first is called non-combined mode where a
51 frame multiframe is used. The basic components of the non-combined broadcast channel are the
frequency control channel (FCCH) which provides a mobile station with a frequency reference for the base
station and allow the mobile station to lock on to the beacon frequency, the synchronization channel (SCH)
which allows the mobile station to synchronize in the time domain, the broadcast control channel (BCCH)
which contains more information needed for the mobile station to connect to the base station, and the
common control channel (CCCH) which contains the information to provide the channel setups and can
originate from the base station or the mobile. Refer to Figure 14-3 on page 404.
Figure 14-3
GSM Multiframe Structure
Combined Broadcast Channel
Two separate 51-frame multiframes are used to form a repeating 102 frame sequence. The main difference
between the combined broadcast channel and the non-combined broadcast channel is that some of the
CCCH channels are replaced with standalone dedicated control channels (SDCCH/4) and slow associated
control channels (SACCH/4). Standalone dedicated control channels are intended for the transfer of
signaling information between a mobile and a base station. The purpose of the slow associated control
channel is to provide channel maintenance. The combined broadcast channel on the ESG simulates the
situation when no data is required to be transmitted to the mobile station but the logical channels are made
available. When this situation occurs a real base station would send dummy bursts, the ESG will therefore
also use dummy bursts. Refer to Figure 14-3 on page 404.
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Broadcast Control Channel (BCCH)
The broadcast control channel (BCCH) informs the mobile station about specific system parameters it needs
to identify the network. These messages include among others, Location Area Code (LAC) and the Mobile
Network Code (MNC). The BCCH appears once every 51-frame multiframe and lasts for four frames
(occurring in frames 2,3,4, and 5). System information messages contain various information for a mobile
station and are transmitted on the BCCH at different times. The ESG implementation will include only the
system information 3 (SI3) message repeated once per 51-frame multiframe. The SI3 message for the ESG
implementation will have four user definable fields and the rest will be fixed. The user definable parameters
are cell identity, which identifies a cell within a location area and the location area identification. The
location identification is made up of the three parameters listed below:
MNC
The mobile network code consists of 12 bits of data. Normally eight bits are used but for
PCS1900 NA, federal regulation mandates that a 3-digit MNC will be used. If two digits
are used then the upper 4 bits of the field are fixed to 1111. For the ESG implementation
the upper four bits are set to 1111 and the field range is 0–255. This field identifies the
network operator.
LAC
The location area code provides 16 bits to allow network administrator to define a
location.
MCC
The mobile country code defines the country the base station is in.
The following SCPI commands can be used to modify or query the system information 3 (SI3) user
definable parameters:
[:SOURce]:RADio[1]|2|3|4:GSM:SLOT0:NORMal:ENCRyption:BCH:CELLid <val>
[:SOURce]:RADio[1]|2|3|4:GSM:SLOT0:NORMal:ENCRyption:BCH:CELLid?
[:SOURce]:RADio[1]|2|3|4:GSM:SLOT0:NORMal:ENCRyption:BCH:MNC <val>
[:SOURce]:RADio[1]|2|3|4:GSM:SLOT0:NORMal:ENCRyption:BCH:MNC?
[:SOURce]:RADio[1]|2|3|4:GSM:SLOT0:NORMal:ENCRyption:BCH:MCC <val>
[:SOURce]:RADio[1]|2|3|4:GSM:SLOT0:NORMal:ENCRyption:BCH:MCC?
[:SOURce]:RADio[1]|2|3|4:GSM:SLOT0:NORMal:ENCRyption:BCH:LAC <val>
[:SOURce]:RADio[1]|2|3|4:GSM:SLOT0:NORMal:ENCRyption:BCH:LAC?
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E-OTD Measurement System Synchronization
To allow an Enhanced Observed Time Difference (E-OTD) measurement to be made it is important that all
the instruments in the system are synchronized. To do this a PSA is used to measure the time from the trigger
pulse to TO - where TO is defined as the middle of the training sequence. The ESG will always produce RF
quicker than the PSA due to a built in delay for the ESG.
Below is an equipment diagram and SCPI command procedure to measure the trigger to TO (TO = middle of
the midamble of a burst) measurement. Some of the SCPI commands used in this procedure to set up the
instruments and make the measurements do not have a front panel equivalent key press. The features are
only available using the remote GPIB interface.
Figure 14-4
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GPIB commands to set up the ESG.
//Select Frequency band, channel, and power.
:FREQuency:CHANnels:BAND BPGSm
:FREQuency:CHANnels:NUMBer 40
:FREQuency:CHANnels:STATe ON
:POWer:LEVel:IMMediate:AMPLitude -10DBM
:OUTPut ON
//Select external data clock for GSM.
:RADio:GSM:BBCLock EXT
:RADio:GSM:SLOT0:NORMal:ENCRyption PN9
:RADio:GSM:BURSt ON
:RADio:GSM:SLOT0:STATe ON
//Select triggering
:RADio:GSM:TRIGger:TYPE:SING
:RADio:GSM:TRIGger:EXT
:RADio:GSM:TRIGger:EXTernal:SOURce EPT1
//Turn on GSM modulation.
:RADio:GSM ON
GPIB commands to set up the 8960.
:CALL:OPER:MODE GBTT
:CALL:BCH 120
:CALL:TCH 1
:CALL:POW -10
:CALL:TCH:TSL 2
:CALL:TRIG:FRAM:NIDL:STAT ON
The 8960 is now generation a broadcast channel (BCH) on absolute radio frequency channel number
(ARFCN) 120, a traffic channel (TCH) on ARFCN 1, and is sending out a trigger pulse for every frame not
idle. The ESG is being triggered to generate a single slot traffic channel on this trigger. In this mode, it is
important that the symbol clock from the 8960 is used as the source for the external data clock on the ESG.
This is important because the two instruments need to have their clocks aligned or the triggering can be
delayed up to 3.69 microseconds. Using the symbol clock from the 8960 as a data clock for the ESG ensures
synchronous operation.
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To make the trigger to TO measurement it is necessary to send the following command using the remote
interface:
:READ:PVT10?
The READ command performs an INIT followed by a FETCH so a new measurement is started each time.
With no averaging the standard deviation should be approximately 4ns for the ESG and 9ns for the 8960.
For this set up the ESG uses a continuous triggering mode, trigger and run. In this mode the ESG waits for a
trigger pulse, then runs and ignores any further trigger pulses.
//Send the following commands to set the trigger mode:
:RADio:GSM:TRIGger:TYPE:CONTinuous TRIG
:RADio:GSM:TRIGger EXT
:RADio:GSM:TRIGger:TYPE CONT
//The ESG is set up to have a non-combined BCH in slot 0 and a normal TCH on slot 2
:RADio:GSM:SLOT0:NORMal ENCRyption BCH1
:RADio:GSM:SLOT2:TYPE:NORMal
:RADio:GSM:SLOT2:NORMal:ENCRyption PN9
At this point the ESG is waiting for a trigger. Sending a CALL statement to the 8960 resets the frame
counters and sets a single trigger at the beginning of the multiframe. Now both the 8960 and the ESG are
running together but not perfectly aligned.
:CALL:TRIG:OUTP:FRAM:SYNC
Measure the trigger to TO for each. If the 8960 is the first burst then it is necessary to restart the system with
a symbol offset applied to the trigger.
Send the following commands to make the ESG ready and align the ESG with the 8960:
:RADio:GSM:TRIGger:TYPE:CONT
:CALL:TRIG:FRAM:SYNC:OFFS xx (where xx is the number of symbols to advance the trigger)
:RADio:GSM:TRIG:EXT:DEL:FINE yy (where yy is the fraction of a symbol necessary for perfect
alignment)
The last command is a call to the 8960 to start up again. Now both bursts should be in alignment and the
frame counters reset.
:CALL:TRIG:OUTP:FRAM:SYNC
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Sample SCPI Command Scripts
This section has two scenarios in which SCPI commands are used to setup the ESG to transmit a Broadcast
Channel (BCH).
Example 1, Setting Up a Non-Combined Broadcast Channel
This example will setup the ESG to generate a Non-Combined Broadcast Channel at 935.2 MHz with a
power level of –10 dBm. A public land mobile network (PLMN) value of 2 will be chosen and a base station
colour code (BCC) value of 3 will be set. The trigger will be setup in “trigger and run” mode which means
that the ESG will start generating a BCH on receipt of the first trigger and any further triggers will be
ignored. The trigger will be setup to use the external pattern trigger 1.
Reset the ESG to its power on state.
*RST
Select the frequency band, channel and power.
:FREQuency:CHANnels:BAND BPGSm
:FREQuency:CHANnels:NUMBer 1
:FREQuency:CHANnels:STATe ON
:POWer:LEVel:IMMediate:AMPLitude -10dBm
:RADio:GSM:BURSt:STATe ON
:RADio:GSM:SLOT0:NORMal:ENCRyption BCH1
:RADio:GSM:SLOT1:DUMMy:TSEQuence #H1C5C5C5
:RADio:GSM:SLOT2:NORMal:ENCRyption PN9
:RADio:GSM:SLOT3:NORMal:ENCRyption PN9
:RADio:GSM:SLOT4:NORMal:ENCRyption PN9
:RADio:GSM:SLOT5:NORMal:ENCRyption PN9
:RADio:GSM:SLOT6:NORMal:ENCRyption PN9
:RADio:GSM:SLOT7:NORMal:ENCRyption PN9
:RADio:GSM:SLOT0:TYPe NORMal
:RADio:GSM:SLOT1:TYPe DUMMy
:RADio:GSM:SLOT2:TYPe NORMal
:RADio:GSM:SLOT3:TYPe NORMal
:RADio:GSM:SLOT4:TYPe NORMal
:RADio:GSM:SLOT5:TYPe NORMal
:RADio:GSM:SLOT6:TYPe NORMal
:RADio:GSM:SLOT7:TYPe NORMal
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Setup the ESG to have a non-combined broadcast channel in slot 0, a dummy burst in slot 1, and the other
time slots will have a normal burst with a PN9 sequence in the payload fields.
Turn each time slot on and select TSC0 for the training bit sequence.
:RADio:GSM:SLOT0:NORMal:TSEQuence
:RADio:GSM:SLOT1:NORMal:TSEQuence
:RADio:GSM:SLOT2:NORMal:TSEQuence
:RADio:GSM:SLOT3:NORMal:TSEQuence
:RADio:GSM:SLOT4:NORMal:TSEQuence
:RADio:GSM:SLOT5:NORMal:TSEQuence
:RADio:GSM:SLOT6:NORMal:TSEQuence
:RADio:GSM:SLOT7:NORMal:TSEQuence
:RADio:GSM:SLOT0:STATe ON
:RADio:GSM:SLOT1:STATe ON
:RADio:GSM:SLOT2:STATe ON
:RADio:GSM:SLOT3:STATe ON
:RADio:GSM:SLOT4:STATe ON
:RADio:GSM:SLOT5:STATe ON
:RADio:GSM:SLOT6:STATe ON
:RADio:GSM:SLOT7:STATe ON
TSC3
TSC3
TSC3
TSC3
TSC3
TSC3
TSC3
TSC3
Setup the public land mobile network and base station color code values.
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:PLMN 2
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:BCC 3
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:CELLid 4
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:MNC 2
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:MCC 2
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:LAC 4
Set the trigger mode to continuous, the trigger type to “trigger and run”, and setup the ESG to accept an
external trigger on EPT1.
:RADio:GSM:TRIGger:TYPE CONT
:RADio:GSM:TRIGger:TYPE:CONTinuous:TYPE TRIGger
:RADio:GSM:TRIGger EXT
:RADio:GSM:TRIGger:EXTernal:SOURce EPT1
Turn the GSM modulation format and RF to ON.
:OUTPut:STATe 1
:SOURce:RADio:GSM:STATe ON
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Example 2, Setting Up a Combined Broadcast Channel
This example will setup the ESG to generate a Combined Broadcast Channel at 935.2 MHz with a power
level of −10 dBm. A public land mobile network (PLMN) value of 4 will be chosen and a base station colour
code (BCC) value of 1 will be set. The trigger will be setup in “trigger and run” mode which means that the
ESG will start generating a BCH on receipt of the first trigger and any further triggers will be ignored. The
trigger will be setup to use the external pattern trigger 1.
Reset the ESG to its power on state.
*RST
Select the frequency band, channel and power.
:FREQuency:CHANnels:BAND BPGSm
:FREQuency:CHANnels:NUMBer 1
:FREQuency:CHANnels:STATe ON
:POWer:LEVel:IMMediate:AMPLitude -10dBm
Setup the ESG to have a Combined Broadcast Channel in slot 0 and all other time slots will have a normal
burst with a PN9 sequence in the payload fields.
:RADio:GSM:BURSt:STATe ON
:RADio:GSM:SLOT0:NORMal:ENCRyption
:RADio:GSM:SLOT1:NORMal:ENCRyption
:RADio:GSM:SLOT2:NORMal:ENCRyption
:RADio:GSM:SLOT3:NORMal:ENCRyption
:RADio:GSM:SLOT4:NORMal:ENCRyption
:RADio:GSM:SLOT5:NORMal:ENCRyption
:RADio:GSM:SLOT6:NORMal:ENCRyption
:RADio:GSM:SLOT7:NORMal:ENCRyption
:RADio:GSM:SLOT0:TYPe NORMal
:RADio:GSM:SLOT1:TYPe NORMal
:RADio:GSM:SLOT2:TYPe NORMal
:RADio:GSM:SLOT3:TYPe NORMal
:RADio:GSM:SLOT4:TYPe NORMal
:RADio:GSM:SLOT5:TYPe NORMal
:RADio:GSM:SLOT6:TYPe NORMal
:RADio:GSM:SLOT7:TYPe NORMal
Chapter 14
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PN9
PN9
PN9
PN9
PN9
PN9
PN9
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Turn each time slot on and select TSC0 for the training bit sequence.
:RADio:GSM:SLOT0:NORMal:TSEQuence
:RADio:GSM:SLOT1:NORMal:TSEQuence
:RADio:GSM:SLOT2:NORMal:TSEQuence
:RADio:GSM:SLOT3:NORMal:TSEQuence
:RADio:GSM:SLOT4:NORMal:TSEQuence
:RADio:GSM:SLOT5:NORMal:TSEQuence
:RADio:GSM:SLOT6:NORMal:TSEQuence
:RADio:GSM:SLOT7:NORMal:TSEQuence
:RADio:GSM:SLOT0:STATe ON
:RADio:GSM:SLOT1:STATe ON
:RADio:GSM:SLOT2:STATe ON
:RADio:GSM:SLOT3:STATe ON
:RADio:GSM:SLOT4:STATe ON
:RADio:GSM:SLOT5:STATe ON
:RADio:GSM:SLOT6:STATe ON
:RADio:GSM:SLOT7:STATe ON
TSC1
TSC1
TSC1
TSC1
TSC1
TSC1
TSC1
TSC1
Setup the public land mobile network (PLMN) and base station color code (BCC) values.
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:PLMN 4
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:BCC 1
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:CELLid 4
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:MNC 4
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:MCC 4
:RADio:GSM:SLOT0:NORMal:ENCRyption:BCH:LAC 4
Set the trigger mode to continuous, the trigger type to “trigger and run”, and setup the ESG to accept an
external trigger on EPT1.
:RADio:GSM:TRIGger:TYPE CONT
:RADio:GSM:TRIGger:TYPE:CONTinuous:TYPE TRIGger
:RADio:GSM:TRIGger EXT
:RADio:GSM:TRIGger:EXTernal:SOURce EPT1
Turn the GSM modulation format and RF to ON.
:OUTPut:STATe 1
:SOURce:RADio:GSM:STATe ON
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DECT Framed Modulation
DECT Framed Modulation
This example teaches you how to build framed real-time I/Q baseband generated DECT modulation for
testing receiver designs. The procedures in this section build on each other and are designed to be used
sequentially.
Activating Framed Data Format
1. Press Preset.
2. Press Mode > Real Time TDMA > DECT > Data Format Pattern Framed.
Configuring the First Timeslot
1. Press Configure Timeslots > Timeslot Type > Custom.
2. Press Configure Custom > Other Patterns > 8 1’s & 8 0’s.
Configuring the Second Timeslot
1. Press Timeslot # > 1 > Enter.
2. Press Timeslot Type > Traffic Bearer.
3. Press Configure Traffic Bearer > B field > Other Patterns > 4 1’s & 4 0’s.
4. Press Return > Timeslot Off On to On > Return.
Generating the Baseband Signal
Press DECT Off On to On.
This generates a DECT signal with an active custom timeslot (#0) and an active traffic bearer timeslot (#1).
The signal generator may require several seconds to build the signal. During this time, Baseband
Reconfiguring appears on the display. After the reconfiguration is complete, the display reads DECT On
and the DECT, ENVLP, and I/Q annunciators appear. The signal is now modulating the RF carrier.
The signal’s configuration data resides in volatile memory and is not recoverable after an instrument preset,
power cycle, or reconfigured signal generation.
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Configuring the RF Output
1. Set the RF output frequency to 1.89 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off to On.
The user-defined DECT signal is now available at the signal generator’s RF OUTPUT connector.
To store this real-time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real-time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
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PHS Framed Modulation
PHS Framed Modulation
This example teaches you how to build framed real-time I/Q baseband generated PHS modulation for testing
receiver designs. The procedures in this section build on each other and are designed to be used sequentially.
Activating Framed Data Format
1. Press Preset.
2. Press Mode > Real Time TDMA > PHS > Data Format Pattern Framed.
Configuring the First Timeslot
1. Press Configure Timeslots > Timeslot Type > Custom.
2. Press Configure Custom > FIX4.
3. Press 1010 > Enter > Return.
Configuring the Second Timeslot
1. Press Control Channel Dnlink Uplink.
2. Press Timeslot Type > Custom.
3. Press Configure Custom > Other Patterns > 4 1’s & 4 0’s.
4. Press Return.
Generating the Baseband Signal
Press PHS Off On to On
This generates a PHS signal with an active downlink custom timeslot (#1) and an active uplink custom
timeslot (#1). The signal generator may require several seconds to build the signal. During this time,
Baseband Reconfiguring appears on the display. After the reconfiguration is complete, the display
reads PHS On and the PHS, ENVLP, and I/Q annunciators appear. The signal is now modulating the RF
carrier.
The signal’s configuration data resides in volatile memory and is not recoverable after an instrument preset,
power cycle, or reconfigured signal generation.
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PHS Framed Modulation
Configuring the RF Output
1. Set the RF output frequency to 1.89515 GHz.
2. Set the output amplitude to 0 dBm.
3. Press RF On/Off to On.
The user-defined PHS signal is now available at the signal generator’s RF OUTPUT connector.
To store this real-time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real-time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
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PDC Framed Modulation
PDC Framed Modulation
This example teaches you how to build framed real-time I/Q baseband generated PDC modulation for
testing receiver designs. The procedures in this section build on each other and are designed to be used
sequentially.
Activating Framed Data Format
1. Press Preset.
2. Press Mode > Real Time TDMA > PDC > Data Format Pattern Framed.
Configuring the First Timeslot
1. Press Configure Timeslots > Timeslot Type > Down TCH.
2. Press Configure Down TCH > TCH > FIX4.
3. Press 1010 > Enter > Return > Return.
Configuring the Second Timeslot
1. Press Rate Full Half.
2. Press Timeslot > 3 > Enter.
3. Press Timeslot Type > Down TCH.
4. Press Configure Down TCH > TCH > Other Patterns > 4 1’s & 4 0’s.
5. Press Return > Timeslot Off On to On > Return.
Generating the Baseband Signal
Press PDC Off On to On.
This generates a half rate PDC signal with an active downlink traffic channel timeslot (#0) and an active
downlink traffic channel timeslot (#3). The signal generator may require several seconds to build the signal.
During this time, Baseband Reconfiguring appears on the display. After the reconfiguration is
complete, the display reads PDC On and the PDC, ENVLP, and I/Q annunciators appear. The signal is now
modulating the RF carrier.
The signal’s configuration data resides in volatile memory and is not recoverable after an instrument preset,
power cycle, or reconfigured signal generation.
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PDC Framed Modulation
Configuring the RF Output
1. Set the RF output frequency to 832 MHz.
2. Set the output amplitude to 0 dBm.
3. Press RF On/Off to On.
The user-defined PDC signal is now available at the signal generator’s RF OUTPUT connector.
To store this real-time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real-time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
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NADC Framed Modulation
NADC Framed Modulation
This example teaches you how to build framed real-time I/Q baseband generated NADC modulation for
testing receiver designs. The procedures in this section build on each other and are designed to be used
sequentially.
Activating Framed Data Format
1. Press Preset.
2. Press Mode > Real Time TDMA > NADC > Data Format Pattern Framed.
Configuring the First Timeslot
1. Press Configure Timeslots > Timeslot Type > Down TCH.
2. Press Configure Down TCH > Data > FIX4.
3. Press 1010 > Enter > Return > Return.
Configuring the Second Timeslot
1. Press Rate Full Half.
2. Press Timeslot > 4 > Enter.
3. Press Timeslot Type > Down TCH.
4. Press Configure Down TCH > Data > Other Patterns > 4 1’s & 4 0’s.
5. Press Return > Timeslot Off On to On > Return.
Generating the Baseband Signal
Press NADC Off On to On.
This generates a half rate NADC signal with an active downlink traffic channel timeslot (#1) and an active
downlink traffic channel timeslot (#4). The signal generator may require several seconds to build the signal.
During this time, Baseband Reconfiguring appears on the display. After the reconfiguration is
complete, the display reads NADC On and the NADC, ENVLP, and I/Q annunciators appear. The signal is
now modulating the RF carrier.
The signal’s configuration data resides in volatile memory and is not recoverable after an instrument preset,
power cycle, or reconfigured signal generation.
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NADC Framed Modulation
Configuring the RF Output
1. Set the RF output frequency to 835 MHz.
2. Set the output amplitude to 0 dBm.
3. Press RF On/Off to On.
The user-defined NADC signal is now available at the signal generator’s RF OUTPUT connector.
To store this real-time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real-time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
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TETRA Framed Modulation
TETRA Framed Modulation
This example teaches you how to build framed real-time I/Q baseband generated TETRA modulation for
testing receiver designs. The procedures in this section build on each other and are designed to be used
sequentially.
Activating Framed Data Format
1. Press Preset.
2. Press Mode > Real Time TDMA > TETRA > Data Format Pattern Framed.
Configuring the First Timeslot
1. Press Configure Timeslots > Timeslot Type > Up Control 1.
2. Press Configure Up Control 1 > Data > FIX4.
3. Press 1010 > Enter > Return > Return.
Configuring the Second Timeslot
1. Press Timeslot > 2 > Enter.
2. Press Timeslot Type > Up Custom.
3. Press Configure Up Custom > Other Patterns > 4 1’s & 4 0’s.
4. Press Timeslot Off On to On > Return.
Generating the Baseband Signal
Press TETRA Off On to On.
This generates a TETRA signal with an active uplink control 1 timeslot (#1) and an active uplink custom
timeslot (#2). The signal generator may require several seconds to build the signal. During this time,
Baseband Reconfiguring appears on the display. After the reconfiguration is complete, the display
reads TETRA On and the TETRA, ENVLP, and I/Q annunciators appear. The signal is now modulating the
RF carrier.
The signal’s configuration data resides in volatile memory and is not recoverable after an instrument preset,
power cycle, or reconfigured signal generation.
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TETRA Framed Modulation
Configuring the RF Output
1. Set the RF output frequency to 1.894880 MHz.
2. Set the output amplitude to 0 dBm.
3. Press RF On/Off to On.
The user-defined TETRA signal is now available at the signal generator’s RF OUTPUT connector.
To store this real-time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real-time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
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15 W-CDMA Digital Modulation for Component Test
(Option 400)
This feature is available only in E4438C ESG Vector Signal Generators with Option 001/601or 002/602. The
following list shows the topics covered by this chapter:
•
“W-CDMA Downlink Modulation” on page 424
•
“W-CDMA Uplink Modulation” on page 436
•
“W-CDMA Concepts” on page 441
•
“W-CDMA Frame Structures” on page 450
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W-CDMA Digital Modulation for Component Test (Option 400)
W-CDMA Downlink Modulation
W-CDMA Downlink Modulation
This section teaches you how to build W-CDMA downlink waveforms for testing component designs. The
waveforms are generated by the signal generator’s internal dual arbitrary waveform generator.
Activating a Predefined W-CDMA Downlink State
This procedure teaches you how to perform the following tasks:
•
“Selecting a Predefined W-CDMA Setup” on page 424
•
“Generating the Waveform” on page 424
•
“Configuring the RF Output” on page 424
Selecting a Predefined W-CDMA Setup
1. Press Preset.
2. Press Mode > W-CDMA > Arb W-CDMA.
3. Press W-CDMA Select > 3 DPCH.
This selects three predefined dedicated physical channels (DPCH) for a downlink waveform. The display
changes to DL WCDMA Setup: 3 DPCH. Downlink is the signal generator’s default setting for link
direction and, therefore, does not need to be set.
Generating the Waveform
Press W-CDMA Off On until On is highlighted.
This generates the predefined 3 DPCH W-CDMA downlink waveform. During waveform generation, the
WCDMA and I/Q annunciators appear and the waveform is stored in volatile ARB memory. The waveform is
now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 2.17 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off until On is highlighted.
The predefined W-CDMA downlink signal is now available at the signal generator’s RF OUTPUT
connector.
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W-CDMA Downlink Modulation
Creating a User-Defined W-CDMA Downlink State
This procedure teaches you how to perform the following tasks:
•
“Selecting a W-CDMA Downlink Setup” on page 425
•
“Editing Downlink Channel Parameters” on page 426
•
“Inserting Additional Channels” on page 428
•
“Clipping the Waveform” on page 428
•
“Generating the Waveform” on page 429
•
“Applying Channel Modifications to an Active Waveform” on page 429
•
“Configuring the RF Output” on page 429
CAUTION
Unless previously saved to the signal generator’s non-volatile memory, modifications made
to predefined channel configurations are lost when changes are made to link direction.
To store a custom W-CDMA state, see “Storing a W-CDMA Downlink/Uplink State” on
page 429.
Selecting a W-CDMA Downlink Setup
1. Press Preset.
2. Press Mode > W-CDMA > Arb W-CDMA.
3. Press W-CDMA Define > Edit Channel Setup.
The channel table editor is now displayed, as shown in the following figure. Notice that a dedicated physical
channel (DPCH) with predefined parameters is the default setup. The horizontal scroll bar at the bottom of
the screen indicates that there are more columns to the right of the Scramble Code column. Use the front
panel knob or right arrow key to move the cursor to view the additional columns.
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W-CDMA Downlink Modulation
Figure 15-1
Editing Downlink Channel Parameters
1. Use the front panel knob or arrow keys to move the cursor to table row 1.
2. Highlight the TPC value (5555).
3. Press Edit Item > 00FF > Enter.
The TPC value has now been modified and the cursor has moved to the next row in the TPC column.
NOTE
TPC values are entered as hexadecimal digits. For information on what these values
represent, refer to “Understanding TPC Values” on page 443.
4. Highlight the value (0.00) in the TFCI Power dB field, which is currently hidden from view.
The horizontal scroll bar at the bottom of the screen indicates that there are columns to the right of the
Scramble Code column.
5. Press Edit Item > 2 > dB.
6. Highlight the value (0.00) in the TPC Power dB field.
7. Press Edit Item > 3 > dB.
8. Highlight the value (0.00) in the Pilot Power dB field.
9. Press Edit Item > 1 > dB.
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NOTE
For additional information on TFCI, TPC, and pilot power offsets, refer to “Understanding
TFCI, TPC, and Pilot Power Offsets” on page 444.
10. Highlight the value (4) in the Pilot Bits field.
11. Press Edit Item > 8.
12. Highlight the value (RANDOM) in the Data field.
13. Press Edit Item > PN9.
14. Highlight the value (STD) in the Scramble Type field.
15. Press Edit Item > Right Alternate.
16. Highlight the value (0) in the Scramble Offset field.
17. Press Edit Item > 1 > Enter.
NOTE
For additional information on Scramble Type and Scramble Offset, refer to “Calculating
Downlink Scramble Codes” on page 446.
The downlink DPCH channel parameters have now been modified, as shown. Other channel parameters can
be modified in the same manner.
Figure 15-2
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W-CDMA Downlink Modulation
Inserting Additional Channels
Press Insert Row > More (1 of 2) > Multiple Channels > Channels > 20 > Enter > Done.
The channel table editor now contains 20 additional channels, as shown in the following figure. The page
only displays six channels. To view the additional channels, press the following keys:
Return > Goto Row > Page Up
Figure 15-3
.
Clipping the Waveform
1. Press Mode Setup > More (1 of 2) > ARB Setup > Waveform Utilities > Clipping.
2. Press Clip |I+jQ| To > 80 > %.
The waveform is now set to be clipped at 80 percent of its peak value.
NOTE
428
If the waveform is active (W-CDMA Off On set to On), clipping settings are not applied until
you press the Apply To Waveform softkey.
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W-CDMA Downlink Modulation
Generating the Waveform
Press Mode Setup > W-CDMA Off On until On is highlighted.
This generates a waveform with the custom W-CDMA downlink state created in the previous sections. The
display changes to DL WCDMA Setup: 1 DPCH (Modified). Note that 1 DPCH refers to the predefined
configuration, not the number of channels in the user-modified waveform.
During waveform generation, the WCDMA and I/Q annunciators appear and the waveform is stored in
volatile ARB memory. The waveform is now modulating the RF carrier.
For instructions on storing this user-defined W-CDMA state to the signal generator’s non-volatile memory,
see “Storing a W-CDMA Downlink/Uplink State” on page 429.
Applying Channel Modifications to an Active Waveform
To apply channel modifications to an active waveform (W-CDMA Off On set to On), you must press the Apply
Channel Setup softkey to force the updated waveform to generate. For example, perform the following steps:
1. Press W-CDMA Define > Edit Channel Setup.
2. Move the cursor to row 2.
3. Press Delete Row > Return > Apply Channel Setup.
Notice that the waveform is regenerated to include the modification of the deleted row. Any changes made in
the Edit Channel Setup table editor while a waveform is active will not be applied until the Apply Channel
Setup softkey is pressed.
Configuring the RF Output
1. Set the RF output frequency to 2.17 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off until On is highlighted.
The custom W-CDMA downlink signal is now available at the signal generator’s RF OUTPUT connector.
Storing a W-CDMA Downlink/Uplink State
This procedure teaches you how to store a user-defined W-CDMA state. If you have not created a W-CDMA
state, complete the steps in the previous section, “Creating a User-Defined W-CDMA Downlink State” on
page 425.
1. Press Mode Setup to return to the top-level W-CDMA menu, where W-CDMA Off On is the first softkey.
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W-CDMA Downlink Modulation
2. Press W-CDMA Define > Store Custom W-CDMA State > Store To File.
If there is already a file name occupying the active entry area, press the following keys:
Editing Keys > Clear Text.
3. Enter a file name using the alpha softkeys and the numeric keypad with a maximum length of 23
characters.
4. Press Enter.
The user-defined W-CDMA downlink/uplink state is now stored in non-volatile memory and the file name is
listed in the catalog of files. Note that the actual waveform is not stored; the parameters for generating the
signal are stored. The RF output amplitude, frequency, and operating state settings are not stored as part of a
user-defined W-CDMA state file.
Recalling a W-CDMA Downlink/Uplink State
This procedure teaches you how to recall a W-CDMA state from the signal generator’s non-volatile memory.
If you have not created and stored a W-CDMA state, complete the steps in the previous sections, “Creating a
User-Defined W-CDMA Downlink State” on page 425 and “Storing a W-CDMA Downlink/Uplink State”
on page 429, then preset the signal generator to clear the stored CDMA waveform from volatile ARB
memory.
1. Press Mode > W-CDMA > Arb W-CDMA.
2. Press W-CDMA Select > Custom W-CDMA State.
3. Highlight the desired file.
4. Press Select File.
5. Press W-CDMA Off On until On is highlighted.
The firmware generates the user-defined W-CDMA waveform in volatile ARB memory. The waveform is
now modulating the RF carrier.
For instruction on configuring the RF output, see “Configuring the RF Output” on page 429.
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W-CDMA Downlink Modulation
Creating a User-Defined Multicarrier W-CDMA State
This procedure teaches you how to perform the following tasks:
•
“Selecting a Multicarrier W-CDMA Setup” on page 431
•
“Adding a Carrier” on page 431
•
“Modifying Carrier Parameters” on page 431
•
“Clipping the Multicarrier Waveform” on page 433
•
“Generating the Waveform” on page 433
•
“Applying Modifications to an Active Multicarrier Waveform” on page 434
•
“Configuring the RF Output” on page 434
Selecting a Multicarrier W-CDMA Setup
1. Press Preset.
2. Press Mode > W-CDMA > Arb W-CDMA.
3. Press Multicarrier Off On > Multicarrier Define.
The Multicarrier WCDMA 3GPP Setup table editor is now displayed, showing parameters for the
default two-carrier setup.
Adding a Carrier
1. Highlight the PCCPCH + SCH carrier in table row 2 and press, Insert Row > 3 DPCH.
This adds a predefined 3 DPCH carrier between the two original default carriers. You can also add a custom
W-CDMA carrier that has been previously created and stored.
Modifying Carrier Parameters
1. Press Return.
2. Highlight the Freq Offset value (7.500000 MHz) for the new 3 DPCH carrier in row 2 and press,
Edit Item > −2.5 > MHz. Refer to, “Multicarrier Setup Page 1” on page 432.
3. Highlight the Power value (0.00 dB) for the new 3 DPCH carrier in row 2 and press, Edit Item > −10 >
dB. Refer to, “Multicarrier Setup Page 1” on page 432.
4. Highlight Primary Scramble Code value N/A for the new 3 DPCH carrier in row 2 and press, Edit
Item > 5 > Enter. Refer to, “Multicarrier Setup Page 2” on page 433.
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5. Highlight the Timing Offset value 0 for the new 3 DPCH carrier in row 2 and press, Edit Item > 3 >
Enter. Refer to, “Multicarrier Setup Page 2” on page 433.
6. Highlight the Initial Phase value 0 for the new 3 DPCH carrier in row 2 and press,
Edit Item > 8 > Enter. Refer to, “Multicarrier Setup Page 2” on page 433.
7. Highlight the Pre-FIR Clipping |I+jQ| value for the new 3 DPCH carrier in row 2 and press,
Edit Item > 50 > %. Refer to, “Multicarrier Setup Page 2” on page 433.
NOTE
Figure 15-4
432
The E4438C allows you to clip each individual channel by setting the I+jQ pre-FIR and
post-FIR clipping percentage in the table editor and clip the composite waveform by setting
the I+jQ percentage using the Composite Waveform Clip softkey.
Multicarrier Setup Page 1
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W-CDMA Downlink Modulation
Figure 15-5
Multicarrier Setup Page 2
You now have a user-defined 3-carrier W-CDMA waveform with a 3 DPCH carrier at frequency offset of
−2.5 MHz, with a power of −10.00 dBm, a primary scramble code of 5, a timing offset of 3, an initial phase
of 8, and pre-FIR clipping at 50%.
Clipping the Multicarrier Waveform
1. Press Mode Setup > More (1 of 2) > ARB Setup > Waveform Utilities > Composite Waveform Clip.
2. Press Clip |I+jQ| To > 80 > %.
The composite multicarrier waveform is now set to be clipped at 80 percent of its original peak value. The
waveform is clipped after FIR filtering.
NOTE
If the waveform is active (W-CDMA Off On set to On), clipping settings are not applied until
you press the Apply Multicarrier softkey.
Generating the Waveform
Press Mode Setup > W-CDMA Off On until On is highlighted.
This generates a waveform with the user-defined multicarrier W-CDMA state created in the previous
sections. The display changes to Multicarrier Setup: 2 Carriers (Modified). Note that
2 Carriers refers to the number of carriers in the predefined configuration, not the number of carriers in the
user-modified waveform.
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During waveform generation, the WCDMA and I/Q annunciators appear and the waveform is stored in
volatile ARB memory. The waveform is now modulating the RF carrier.
For instructions on storing this user-defined multicarrier W-CDMA state to the signal generator’s
non-volatile memory, see “Storing a Multicarrier W-CDMA State” on page 434.
Applying Modifications to an Active Multicarrier Waveform
1. Press Multicarrier Define.
2. Move the cursor to row 2.
3. Press Delete Row > Apply Multicarrier.
Notice that the waveform is regenerated to include the modification of the deleted row. Any changes made to
an active multicarrier waveform will not be applied until the Apply Multicarrier softkey is pressed.
Configuring the RF Output
1. Set the RF output frequency to 2.17 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off until On is highlighted.
The user-defined multicarrier W-CDMA signal is now available at the signal generator’s
RF OUTPUT connector.
Storing a Multicarrier W-CDMA State
This procedure teaches you how to store a multicarrier W-CDMA state to the signal generator’s non-volatile
memory.
If you have not created a multicarrier W-CDMA state, complete the steps in the previous section, “Creating
a User-Defined Multicarrier W-CDMA State” on page 431.
1. Press Mode Setup to return to the top-level W-CDMA menu, where W-CDMA Off On is the first softkey.
2. Press Multicarrier Define > Store Custom Multicarrier > Store To File.
If there is already a file name from the Catalog of MDWCDMA Files occupying the active entry area,
press the following keys:
Editing Keys > Clear Text.
3. Enter a file name (for example, 3CARRIER) using the alpha keys and the numeric keypad with a
maximum length of 23 characters.
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4. Press Enter.
The user-defined multicarrier W-CDMA state is now stored in non-volatile memory and the file name is
listed in the Catalog of MDWCDMA Files. Note that the actual waveform is not stored; the parameters
for generating the signal are stored. The RF output amplitude, frequency, and operating state settings are not
stored as part of a user-defined W-CDMA state file.
Recalling a Multicarrier W-CDMA State
This procedure teaches you how to recall a multicarrier W-CDMA state from the signal generator’s
non-volatile memory.
If you have not created and stored a multicarrier W-CDMA state, complete the steps in the previous
sections, “Creating a User-Defined Multicarrier W-CDMA State” on page 431 and “Storing a Multicarrier
W-CDMA State” on page 434.
1. Press Preset to clear the stored W-CDMA waveform from volatile ARB memory.
2. Press Mode > W-CDMA > Arb W-CDMA.
3. Press Multicarrier Off On.
4. Press W-CDMA Select > Custom W-CDMA Multicarrier.
5. Highlight the desired file (for example, 3CARRIER).
6. Press Select File.
7. Press W-CDMA Off On until On is highlighted.
The firmware generates the selected multicarrier W-CDMA waveform in volatile ARB memory. The
waveform is now modulating the RF carrier.
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W-CDMA Uplink Modulation
W-CDMA Uplink Modulation
This section teaches you how to build uplink 3GPP 12-2004 W-CDMA waveforms for testing component
designs. The waveforms are generated by the signal generator’s internal dual arbitrary waveform generator.
Creating a Predefined W-CDMA Uplink State
This procedure teaches you how to perform the following tasks:
•
“Selecting a Predefined W-CDMA Setup” on page 436
•
“Generating the Waveform” on page 436
•
“Configuring the RF Output” on page 436
Selecting a Predefined W-CDMA Setup
1. Press Preset.
2. Press Mode > W-CDMA > Arb W-CDMA > Link Down Up.
3. Press W-CDMA Select > DPCCH + 3 DPDCH.
This selects a predefined setup, which consists of one dedicated physical control channel (DPCCH) and
three dedicated physical data channels (DPDCH) for an uplink waveform. The display changes to UL
WCDMA Setup: DPCCH + 3 DPDCH.
Generating the Waveform
Press W-CDMA Off On until On is highlighted.
This generates a predefined W-CDMA uplink waveform with a DPCCH and 3 DPDCH channels. During
waveform generation, the WCDMA and I/Q annunciators appear and the waveform is stored in volatile ARB
memory. The waveform is now modulating the RF carrier.
Configuring the RF Output
1. Set the RF output frequency to 2.17 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off until On is highlighted.
The predefined W-CDMA uplink signal is now available at the signal generator’s RF OUTPUT connector.
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W-CDMA Uplink Modulation
Creating a User-Defined W-CDMA Uplink State
This procedure teaches you how to perform the following tasks:
•
“Selecting a W-CDMA Uplink Setup” on page 437
•
“Editing Uplink Channel Parameters” on page 438
•
“Inserting Additional Channels and Modifying I/Q Settings” on page 438
•
“Clipping the Waveform” on page 439
•
“Generating the Waveform” on page 439
•
“Applying Channel Modifications to an Active Waveform” on page 440
•
“Configuring the RF Output” on page 440
CAUTION
Unless previously saved to the signal generator’s non-volatile memory, modifications made
to predefined channel configurations are lost when changes are made to link direction.
To store a custom W-CDMA state, see “Storing a W-CDMA Downlink/Uplink State” on
page 429.
Selecting a W-CDMA Uplink Setup
1. Press Preset.
2. Press Mode > W-CDMA > Arb W-CDMA > Link Down Up.
3. Press W-CDMA Define > Edit Channel Setup.
The channel table editor is now displayed, as shown in the following figure. Notice that a dedicated physical
control channel (DPCCH) with predefined parameters is the default selection. The horizontal scroll bar at
the bottom of the screen indicates that there are more columns to the right of the Data column. Use the front
panel knob or right arrow key to move the cursor to view the additional columns.
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W-CDMA Uplink Modulation
Figure 15-6
Editing Uplink Channel Parameters
1. Use the front panel knob or arrow keys to move the cursor to table row 1.
2. Highlight the TPC value (5555).
3. Press Edit Item > 00FF > Enter.
The TPC value has now been modified and the cursor has moved to the next row in the TPC column. Other
channel parameters can be modified in the same manner.
NOTE
TPC values are entered as hexadecimal digits (0-9, A-F). For information on what these
values represent, refer to “Understanding TPC Values” on page 443.
Inserting Additional Channels and Modifying I/Q Settings
1. Press Insert DPDCH > Channels > 6 > Enter > Done.
2. Press More (1 of 2) > Second DPDCH I Q until the letter I is highlighted.
The I/Q setting for the second DPDCH channel (row 3) has changed from Q to I. Additionally, all
subsequent channels have also switched I/Q settings, as shown in the following figure.
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W-CDMA Uplink Modulation
Figure 15-7
Clipping the Waveform
1. Press Mode Setup > More (1 of 2) > ARB Setup > Waveform Utilities > Clipping.
2. Press Clip |I+jQ| To > 80 > %.
The waveform is now set to be clipped at 80 percent of its peak value.
NOTE
If the waveform is active (W-CDMA Off On set to On), clipping settings are not applied until
you press the Apply To Waveform softkey.
Generating the Waveform
Press Mode Setup > W-CDMA Off On until On is highlighted.
This generates a waveform with the custom W-CDMA uplink state created in the previous sections. The
display changes to UL WCDMA Setup: DPCCH (Modified). During waveform generation, the WCDMA
and I/Q annunciators appear and the waveform is stored in volatile ARB memory. The waveform is now
modulating the RF carrier.
For instructions on storing this custom CDMA state to the signal generator’s non-volatile memory, see
“Storing a W-CDMA Downlink/Uplink State” on page 429.
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W-CDMA Uplink Modulation
Applying Channel Modifications to an Active Waveform
To apply channel modifications to an active waveform (W-CDMA Off On set to On), you must first press the
Apply Channel Setup softkey before the updated waveform is generated. For example, perform the following
steps:
1. Press W-CDMA Define > Edit Channel Setup.
2. Move the cursor to row 2.
3. Press Delete Row > Return > Apply Channel Setup.
Notice that the waveform is regenerated to include the modification of the deleted row. Any changes made in
the Edit Channel Setup table editor while a waveform is active will not be applied until the Apply Channel
Setup softkey is pressed.
Configuring the RF Output
1. Set the RF output frequency to 2.17 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off until On is highlighted.
The custom W-CDMA uplink signal is now available at the signal generator’s RF OUTPUT connector.
To store a W-CDMA uplink state, refer to “Storing a W-CDMA Downlink/Uplink State” on page 429.
To recall a W-CDMA uplink state, refer to “Recalling a W-CDMA Downlink/Uplink State” on page 430.
440
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W-CDMA Concepts
W-CDMA Concepts
Figure 15-8
Chapter 15
Downlink Channel Structure
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W-CDMA Digital Modulation for Component Test (Option 400)
W-CDMA Concepts
Figure 15-9
442
Uplink Channel Structure
Chapter 15
W-CDMA Digital Modulation for Component Test (Option 400)
W-CDMA Concepts
Understanding TPC Values
TPC values determine how the transmit power of the receiving base or mobile station will vary. In the
channel table editor, TPC values are represented in hexadecimal format to simplify entries and
modifications. Figure 15-10 shows the channel table editor with the TPC value, 7F80, highlighted.
Figure 15-10
Highlighted TPC Value
Hexadecimal TPC values are converted to their binary equivalent. In this example, the value 7F80 becomes
111 1111 1000 0000. Notice that there are 15 digits in the binary TPC value. Because one frame contains
15 timeslots, one binary digit is assigned to each timeslot (see Figure 15-11 on page 444). The assigned bit is
then repeated enough times to fill the TPC bit field (see the NTPC column of Table 15-7). Since the example
in Figure 15-11 uses two TPC bits per timeslot, the values are either 11 or 00.
The TPC bits that are ones direct the receiving base or mobile station to increase its transmit power by an
amount specified by the W-CDMA standard. Likewise, TPC bits that are zeros cause the power to decrease
by the same amount. In this example, the transmit power is increasing over timeslots 0 through 7 and
decreasing over timeslots 8 through 14.
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W-CDMA Concepts
Figure 15-11
TPC Bits per Timeslot
Understanding TFCI, TPC, and Pilot Power Offsets
TFCI, TPC, and Pilot power offsets (PO), which are applied to downlink control channels (DPCCH), are
relative to the transmit power for data channels (DPDCH). Usually, these offsets are set to a positive value
(refer to Figure 15-12 on page 444). The intent is to transmit control symbols at a higher level than data
symbols to maintain the link between mobile and base. Because only the DPCCH transmit power is offset,
the total transmit power is minimized and less noise is generated in the system.
Figure 15-12
444
TFCI, TPC, and Pilot Power
Chapter 15
W-CDMA Digital Modulation for Component Test (Option 400)
W-CDMA Concepts
The display in Figure 15-13 shows that the channel in row 6 of the table editor has the data transmit power
(Power dB) set to −6.02 dB with the following offsets: TFCI Power set to 2.00 dB, TPC Power set to
3.00 dB, and Pilot Power set to 1.00 dB. Because of these offsets, the control symbols corresponding to
TFCI, TPC, and Pilot will transmit at −4.02 dB, −3.02 dB, and −5.02 dB respectively.
Figure 15-13
Chapter 15
Table Editor Showing TFCI, TPC, and Pilot Power Offsets
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W-CDMA Digital Modulation for Component Test (Option 400)
W-CDMA Concepts
Calculating Downlink Scramble Codes
The Option 400 signal generator implements scrambling codes for downlink channels in compliance with
3GPP specifications. This is done through the use of Scramble Code, Scramble Type, and Scramble
Offset fields in the downlink Edit Channel Setup table editor. These fields are linked so that an entry to
any field affects the actual scramble code. To better understand the relationship, please refer to the following
formula.
n = ( 16 × i ) + k + m
Table 15-1
Where n = scramble code
Range: 0 to 24575
i = scramble code field input
Primary: Range 0 to 511
Secondary: Range 0 to 511
k = scramble offset field input
Range: 0 to 15
m = scramble type field input
Standard: adds 0
Right Alternate: adds 16384
Left Alternate: adds 8192
Figure 15-14
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W-CDMA Concepts
The Scramble Code field has two sets: primary and secondary, each with a field range of 0 through 511.
The primary and secondary sets are determined by the Scramble Offset field. If the Scramble
Offset field is zero, then the scramble code is in the primary set. Any non-zero entry enables the secondary
set. The Scramble Offset field has a range of 0 through 15.
The Scramble Type field has three modes: Standard, Right Alternate, and Left Alternate. The standard
scramble type has a value of zero and does not contribute to the scramble code. Selecting the right alternate
adds 16384 to the actual scramble code, whereas the left alternate adds 8192.
Scramble Codes with Standard Scramble Type
A primary scramble code is the product of the Scramble Code field entry and 16. Therefore, the primary
scramble code set contains all multiples of 16 from 0 through 8176.
A secondary scramble code is the sum of the non-zero Scramble Offset field entry and the primary
scramble code. The secondary scramble code set uses the numbers in between the multiples of 16.
Thus, all numbers from 0 through 8191 are available for scramble codes when using the standard scramble
type.
Refer to the following for examples of scramble codes generated with the primary and secondary sets:
n = ( 16 × i ) + k + m
Table 15-2
Where n = scramble code
i = scramble code field input
k = scramble offset field input
m = scramble type field input
Table 15-3
A: Primary set
Chapter 15
B: Secondary set
i=6
i=8
k=0
k=7
m=0
m=0
n = 96
n = 135
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W-CDMA Digital Modulation for Component Test (Option 400)
W-CDMA Concepts
Figure 15-15
Scramble Codes with Right and Left Alternate Scramble Types
Recalling that right alternate adds 16384 to the scramble code and left alternate adds 8192, refer to the
following examples of scramble codes generated with the right alternate and left alternate scramble types:
n = ( 16 × i ) + k + m
Table 15-4
Where n = scramble code
i = scramble code field input
k = scramble offset field input
m = scramble type field input
Table 15-5
A: Primary set + Left Alternate
i=6
448
B: Secondary set + Right Alternate
i=8
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W-CDMA Digital Modulation for Component Test (Option 400)
W-CDMA Concepts
Table 15-5
A: Primary set + Left Alternate
B: Secondary set + Right Alternate
k=0
k=7
m = 8192
m = 16384
n = 8288
n = 16519
Figure 15-16
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W-CDMA Frame Structures
W-CDMA Frame Structures
This section contains graphical representations of W-CDMA frame structures, with associated tables, for
both downlink and uplink channels.
Downlink PICH Frame Structure
Figure 15-17
450
PICH Frame Structure
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W-CDMA Frame Structures
Downlink PCCPCH + SCH Frame Structure
Figure 15-18
PCCPCH + SCH Frame Structure
Table 15-6
Lengths of PCCPCH + SCH Fields
Parameter
Symbols Per Slot
Ndata
9
NSCHa
1
a. SCH comprises PSCH and SSCH
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Downlink DPCCH/DPDCH Frame Structure
Figure 15-19
DPCCH/DPDCH Frame Structure
Table 15-7
DPDCH and DPCCH Fields
15
7.5
512
15
7.5
512
30
15
30
Bits/Slot
DPDCH Bits/Slot
TOTAL
DPCCH
DPDCH
Spread Factor
Channel Symbol
Rate (Ksps)
Channel Bit
Rate (Kbps)
Bits/Frame
Ndata1
DPCCH
Bits/Slot
Ndata2
NTFCI
NTPC
Npilot
90
150
10
0
4
0
2
4
30
120
150
10
0
2
2
2
4
256
240
60
300
20
2
14
0
2
2a
15
256
210
90
300
20
2
12
2
2
2a
30
15
256
210
90
300
20
2
12
0
2
4a
30
15
256
180
120
300
20
2
10
2
2
4a
30
15
256
150
150
300
20
2
8
0
2
8a
30
15
256
120
180
300
20
2
6
2
2
8a
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W-CDMA Frame Structures
Table 15-7
DPDCH and DPCCH Fields (Continued)
30
128
510
90
600
40
6
28
0
2
4a
60
30
128
480
120
600
40
6
26
2
2
4a
60
30
128
450
150
600
40
6
24
0
2
8a
60
30
128
420
180
600
40
6
22
2
2
8a
120
60
64
900
300
1200
80
12
48
8b
4
8
240
120
32
2100
300
2400
160
28
112
8b
4
8
480
240
16
4320
480
4800
320
56
232
8b
8
16
960
480
8
9120
480
9600
640
120
488
8b
8
16
192
0
960
4
1872
0
480
19200
1280
248
1000
8b
8
16
TOTAL
Bits/Slot
60
Channel Bit
Rate (Kbps)
DPCCH
DPCCH
Bits/Slot
DPDCH
DPDCH Bits/Slot
Spread Factor
Channel Symbol
Rate (Ksps)
Bits/Frame
Ndata1
Ndata2
NTFCI
NTPC
Npilot
a. The number of pilot bits can vary with channel symbol rates of 15 and 30 ksps.
b. If TFCI bits are not used, then DTX (discontinuous transmission) is used in the TFCI field.
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Uplink DPCCH/DPDCH Frame Structure
Figure 15-20
DPCCH/DPDCH Frame Structure
Table 15-8
DPDCH Fields
Channel Bit Rate
(kbps)
Channel Symbol Rate
(ksps)
Spread
Factor
15
15
256
150
10
10
30
30
128
300
20
20
60
60
64
600
40
40
120
120
32
1200
80
80
240
240
16
2400
160
160
480
480
8
4800
320
320
960
960
4
9600
640
640
454
Bits/Frame
Ndata
Bits/Slot
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W-CDMA Digital Modulation for Component Test (Option 400)
W-CDMA Frame Structures
Table 15-9
DPCCH Fields
Channel Bit
Rate (kbps)
Channel
Symbol
Rate
(ksps)
15
15
256
150
10
6
2
0
2
15
15
256
150
10
8
0
0
2
15
15
256
150
10
5
2
1
2
15
15
256
150
10
7
0
1
2
15
15
256
150
10
6
0
2
2
15
15
256
150
10
5
2
2
1
Chapter 15
Spread
Factor
Bits/Frame
NTFCI
Npilot
Bits/Slot
NFBI
NTPC
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W-CDMA Frame Structures
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Chapter 15
16 W-CDMA Uplink Digital Modulation for Receiver
Test (Option 400)
The following features are available only in E4438C ESG Vector Signal Generators with Option 001/601or
002/602.
This chapter teaches you how to build fully coded W-CDMA uplink modulated signals for testing base
station receiver designs and provides information on how the W-CDMA uplink format is implemented
within the ESG. The modulation is generated by the signal generator’s internal baseband generator. There are
two channel modes for transmitting an uplink signal, PRACH and DPCH. This chapter covers both channel
modes.
The following list shows the topics covered by this chapter:
•
“Equipment Setup” on page 459
•
“Understanding the PRACH” on page 461
•
“Generating a Single PRACH Signal” on page 474
•
“Multiple PRACH Overview” on page 486
•
“Setting Up a Multiple PRACH Signal” on page 491
•
“Overload Testing with Multiple PRACHs—Multiple ESGs” on page 509
•
“DPCH” on page 516
•
“Compressed Mode Single Transmission Gap Pattern Sequence (TGPS) Overview” on page 529
•
“Setting Up Compressed Mode for a Single TGPS Transmission” on page 531
•
“Compressed Mode Multiple Transmission Gap Pattern Sequence (TGPS) Overview” on page 540
•
“Setting Up Compressed Mode for a Multiple TGPS Transmission” on page 543
•
“Configuring the UE Setup” on page 554
•
“Locating Rear Panel Input Signal Connectors” on page 555
•
“Configuring Rear Panel Output Signals” on page 557
•
“Adjusting Code Domain Power” on page 560
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W-CDMA Uplink Digital Modulation for Receiver Test (Option 400)
•
“W-CDMA Uplink Concepts” on page 562
•
“DPCCH/DPDCH Frame Structure” on page 587
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Equipment Setup
Equipment Setup
The following diagrams show the equipment setups that are used to measure the output signal generated
using the ESG. These setups are used for most of the procedures contained within this chapter and they apply
to both the PRACH and DPCH channel modes.
ESG and Agilent E4440A PSA Spectrum Analyzer Setup
Unless stated otherwise in a procedure, both the PRACH and DPCH procedures use the setup shown in
Figure 16-1 for viewing the ESG output.
Figure 16-1
PSA Setup
ESG and Base Transceiver Station (BTS) Setup
Unless stated otherwise in a procedure, both the PRACH and DPCH procedures in this chapter use the base
station setup shown in Figure 16-2. For more information on connecting the ESG to a base station, see
“Connecting the ESG to a W-CDMA Base Station” on page 564.
Chapter 16
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Equipment Setup
Figure 16-2
460
Base Transceiver Station Setup
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W-CDMA Uplink Digital Modulation for Receiver Test (Option 400)
Understanding the PRACH
Understanding the PRACH
Overview
The PRACH is used by the UE (user equipment/mobile) to signal and establish communications with a base
station. It consists of two components, a preamble and message part. However the PRACH, in an actual UE
to base station application, initially transmits only the preamble. The preamble is used to signal the base
station that a UE is trying to establish a connection, and is repeated until it receives an acknowledgment in
the form of an AICH (acquisition indication channel). Once the preamble has been identified by the base
station, the base station transmits the AICH. When the UE receives the AICH, it then sends the message part
of the PRACH transmission. The message part contains the synchronization and request data used in
establishing the base station connection.
There are two modes of PRACH operation within the ESG, single and multiple PRACH. The single PRACH
mode offers greater flexibility in configuring the PRACH signal, whereas the multiple PRACH mode gives
you the ability to transmit multiple PRACHs within an 80 ms time period. In this mode, you can configure
up to eight different UEs each having its own signature. In addition, each UE can transmit multiple PRACHs
within an 80 ms time period.
The ESG gives you the option of transmitting only the preamble or the preamble and message part. This
gives you the ability to simulate an actual PRACH transmission where multiple preambles may be
transmitted before the UE receives an acknowledgment (AICH) from a base station. In the single PRACH
mode, you can even configure the message part to transmit when an AICH trigger is received.
In addition to controlling many other parameters of the PRACH, you can adjust the preamble power, the
message part power, the distance between the preamble and the message part, the number of preambles prior
to the message part transmission (single PRACH mode only), and select a slot format according to the 3GPP
standards.
Access Slots
The access slots provide a well defined time interval for indicating the beginning of a PRACH transmission.
An access slot is 5120 chips long (1.33 ms) and there are 15 access slots per two 10 ms radio frames (or 7.5
access slots per radio frame). A radio frame segments the transmission into blocks of time and assists in
synchronizing the mobile transmission with the base station. So a 20 ms message part is transmitted over
two consecutive radio frames.
Access slots apply to both the uplink and downlink transmissions. In an actual UE to base station
transmission, the UE transmits its access slots before it receives the base station’s transmission of access
slots, thus creating an offset between the two. This offset is used to time the reception of the AICH by the
UE. This timing/offset of the AICH is called Tp-a (the distance from the beginning of the preamble to the
beginning of the AICH transmission) and is defined in the 3GPP standards. The PRACH also uses the access
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Understanding the PRACH
slots to set the timing/distance between preamble transmissions (Tp-p) and the preamble and the message
part (Tp-m). Figure 16-3 shows these timing relationships. You will notice that all measurements are from
the beginning of one component to the next.
Figure 16-3
Access Slot Timing
AICH
One Access Slot
AICH Access
Slots RX at UE
Preamble
Tp-a
Message Part
PRACH Access
Slots TX at UE
Tp-p
Tp-m
The preamble is 4096 chips in length (1.067 ms), so it does not occupy the entire length of an access slot.
When a 10 ms message part (7.5 access slots) is used, it only partially occupies the last access slot.
In multiple PRACH mode, the ESG provides you access slot resolution. Because of this, you can select the
access slot for the beginning of your PRACH transmission. However when transmitting multiple PRACHs
for the same UE with the ESG, they cannot occupy any of the same access slots within an 80 ms time period.
If they do, the subsequent (second PRACH, etc.) PRACH transmission that uses any of the same access
slots, will not occur. See “Understanding the 80 ms Transmission/Time Period” on page 486 for more
information.
Preamble
The preamble is used to signal a base station that a UE is trying to establish communications. It is composed
of a complex signature and scrambling code that is used by the base station to uniquely identify the UE. This
is a 1.067 ms bursted signal, and is the first part of the PRACH transmission.
Signatures
A signature is a series of 16 bits that is repeated 256 times within a single preamble. These signatures are
shown in the 3GPP standards. The signature is the first of two parts used in the spreading of the preamble. It
points to a node within the channelization codes that corresponds to a spread factor (SF) of 16. This node,
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within the SF=16 group, has sub-trees (OVSF codes) that are used in the channelization/spreading of the
message part.
A base station can simultaneously receive 16 different UEs, and all base stations use the same 16 signatures.
Using the BCH (broadcast channel), a base station tells each UE which signature to use and then uses the
signature to determine which UE it is communicating with.
Scrambling Codes
The scrambling code, in most cases, is unique to the base station and it identifies the base station that the UE
is communicating with. In an actual UE to base station transmission, the base station tells the UE which
scrambling code to use. This scrambling code is then used in connection with the signature to uniquely
identify the UE to the base station. The addition of the scrambling code is the second part of the spreading.
There are 8192 (0 to 8191) different scrambling codes. The value selected as the scrambling code is actually
the seed to generate the code sequence. The same scrambling code is used for both the preamble and
message part. However the preamble uses only the first 4096 chips of the selected scrambling code.
Message Part
The message part is transmitted as part of the PRACH after the UE receives the AICH from the base station.
It contains the information necessary for the UE to establish a link with the base station. This information is
transmitted in two parts, a control part and a data part. These two parts form the message part. Each part has
its own power level that influences the overall message part power. See “Power Control” on page 465 for
more information.
There are three groups of parameters that the ESG lets you set for controlling the message part: control part,
data part, and the message part as a whole. The message part can be set to transmit within either a 10 or
20 ms time period called a TTI (transmission time interval).
Structure
Each 10 ms message part is divided into 15 slots (two slots per access slot). Each of the 15 slots carry the
two parts that compose the message part, the control part and the data part. These two parts are transmitted
in parallel. This is similar to the DPCH (dedicated physical channel) that consists of a control channel
(DPCCH, dedicated physical control channel) and a data channel (DPDCH, dedicated physical data
channel). Figure 16-4 shows how the message part is formatted with the control part and data part.
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Understanding the PRACH
Figure 16-4
Message Part Structure
The control part carries the pilot and TFCI (transport format combination indicator) bits. The pilot bits are
used by the base station to synchronize with the UE. The TFCI bits are used by the base station to determine
the data format being used by the transport channel. For example, this would let the base station know the
number of data blocks, the data block size, bit sequence, and number of CRC bits that are being used by the
transport channel. The TFCI pattern, relative to a transport channel configuration, is determined by the base
station network; it is not defined by the 3GPP standards. The 3GPP standards define only the number of
transmitted TFCI bit.
The data part contains only data bits and is the request information used for establishing a connection with
the base station.
Slot Formats
Slot formats are used to determine the transmitted frame structure such as the symbol rate, the number of
bits per frame, and the spread factor. Each slot format is defined in the 3GPP standards and implemented in
the ESG. The control part and data part each have their own slot formats and they are applied to the 15 slots
per 10 ms message part. The available slot formats are shown in Figure 16-5 and Figure 16-6.
If you are using the transport channel as the message part data type, you can inadvertently set values within
the transport channel that conflict with the current slot format. When this occurs, an error will be displayed
and you will need to either correct the transport channel values or select an appropriate data part slot format.
The control part only has one slot format, so its configuration is static, see Figure 16-5.
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Figure 16-5
Control Part Slot Format
Unlike the control part, the data part has multiple slot formats that enable it to transmit at different data rates.
This is shown in Figure 16-6.
Figure 16-6
Data Part Slot Format
Message Part Scrambling Codes
As stated in “Scrambling Codes” on page 463, the same code is used for both the message part and the
preamble. However the starting chip for the message part is shifted by 4096 chips from the preamble code.
The message part contains 38400 scrambling chips and they are repeated every 10 ms (every radio frame).
So a 20 ms message part would have two repetitions of the same code.
Power Control
The PRACH power is controlled by setting the preamble and the message part power. The PRACH power is
determined by the component (preamble or message part) of the PRACH that has the highest power level. If
both components have the same power level, then both components individually equal the PRACH power
level. The message part power is comprised of the absolute powers for the control part and data part. A
PRACH power value can be entered that exceeds the current displayed carrier power and vice versa. But in
reality, the PRACH power equals the carrier power; it cannot exceed it. When a PRACH over power
condition occurs, the ESG will automatically adjust the PRACH power or the carrier power to keep them
within limits. In the multiple PRACH mode, the ESG maintains an 18.06 dB offset between the carrier
power and the PRACH power level. This is so the ESG can accommodate the additional power required
when more UEs (user equipment/mobiles) are utilized (see “Understanding the Power Offset Between the
Carrier and the Multiple PRACH” on page 489 for more information).
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Understanding the PRACH
There are three areas that control the PRACH power level, the preamble power, the data part power, and the
control part power. Each of these areas are explained in the following sections. Figure 16-7 shows these
areas on the PRACH timing setup display while in the Pp-m power setup mode. Refer to “Power Control
Modes” on page 471 for more information on the power setup modes. The power control display is accessed
using the PRACH Power Setup softkey.
Figure 16-7
PRACH Power Control Areas
Pp-m Power Mode Selected
Controls the Control Part Power
Controls the Preamble Power
Controls the Data Part Power
Preamble Power
The preamble power is an absolute value (dBm) and is adjusted in the ESG by changing the value in the Max
Pwr field. Its value is used in determining the control part power level, which influences the total message
part power. See “Control Part Power” for more information.
The preamble power can be adjusted so that it exceeds the current carrier power. When this occurs, the ESG
will automatically adjust the carrier power. The reverse is also true when you enter a new carrier power.
Control Part Power
The control part power is an absolute value (dBm) that is set indirectly and with respect to the preamble. It is
derived from the sum of the highest preamble power and the Pp-m value.
The Pp-m is an offset value (dB) that determines the power difference between the control part and the
preamble powers (Pp-m = CntldBm - PredBm). (See Figure 16-8.) So by adjusting your Pp-m value, you
change the control part power with respect to the preamble.
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To calculate the control part power, use the following formula:
CntldBm = PredBm + Pp-m
CntldBm is the control part power that is the sum of the preamble power (PredBm) and the Pp-m value. The
preamble power is represented by the Max Pwr field on the ESG.
Since the control part power is directly related to the Pp-m value, this means that when the Pp-m value is
positive, the control part power is greater than the preamble power and the message part power will also be
greater than the preamble power by at least the Pp-m value. Conversely when the Pp-m value is negative, the
control part power is less than the preamble power and the message part can also be less than the preamble
power depending on the data part power level. Figure 16-8 shows an example of the influence of the control
part power when the Pp-m value is positive and the data part power is low enough that it has minimal impact
on the overall message part power.
Figure 16-8
Control Part Power Determining Message Part Power
Message Part
Data Part
Pp-m
Control Part
Preamble
Data Part Power
The data part power is not directly entered. It is adjusted and calculated using the difference between relative
power values. These relative powers are shown as Ctrl Pwr and Data Pwr on the ESG. The power values
can be entered using random values, or in compliance with the 3GPP standards, they can be controlled using
gain factors called betas. The 3GPP standard refers to them as Bc (control beta) and Bd (data beta). On the
ESG, they are shown as Ctrl Beta and Data Beta. Each beta (control and data) has 16 different values
numbered 0 to 15, and the values 1 through 15 are used to create an amplitude/voltage ratio for calculating
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the relative power levels. A beta of zero means the power has been turned off for that particular relative
power. Table 16-1 shows the beta values and their respective ratios.
Table 16-1
Control and Data Part Betas
Beta Values for Control
and Data Beta
Amplitude/Voltage Ratios
15
1
14
14/15
13
13/15
12
12/15
11
11/15
10
10/15
9
9/15
8
8/15
7
7/15
6
6/15
5
5/15
4
4/15
3
3/15
2
2/15
1
1/15
0
Offa
a. -40 dB for the ESG relative power levels
When betas are used, the control and data relative powers are calculated using the following formula:
Relative power = 20 Log (beta/15)
According to the 3GPP standards, at any instant in time, one of the betas for either the control or data power
will result in a ratio of one (0.00 dB). However the ESG gives you the flexibility to set your relative power
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values to meet your testing needs. Which ever method you use, the highest power value is used as your data
part power reference relative to the control part power.
NOTE
When a random power value is used, the beta value is replaced by a hyphen, since it cannot
be defined by the beta values.
Using the relative power formula, a control beta of five would result in a relative control power value of
−9.54 dB. If the relative data power is 0.00 dB (beta of 15), this would mean that the data part power is
9.54 dB higher than the control part power. If the relative data power is −9.54 dB and the relative control
power is 0.00 dB, this would mean that the data part power was 9.54 dB lower than the control part power.
When the betas are the same value, this means that the control part and data part powers are the same power
levels. This results in a 3 dB (two times the control part power) increase in the message part power.
To calculate the data part absolute power, perform the following steps where
Pwrdiff = difference between relative power values
Cntlpwr = relative control power
Datapwr = relative data power
CntldBm = control part power
DatadBm = data part power
PredBm = preamble power
1. Calculate the absolute power for the control part.
CntldBm = PredBm + Pp-m
The preamble power is represented by the Max Pwr field on the ESG.
2. Calculate the relative power difference between the two relative power values.
Pwrdiff = Datapwr - Cntlpwr
3. Calculate the absolute power for the data part.
DatadBm = CntldBm + Pwrdiff
Do not confuse the control power as a means of adjusting the control part power. Remember the control part
power is the sum of the preamble and the Pp-m values. The control power merely serves as a reference for
the data part power relative to the control part power. Figure 16-9 demonstrates the message part power
when the data part has a greater influence.
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Figure 16-9
Data Part Power Determining Message Part Power
Message Part Power = −25 dBm
(control part power (watts) + data part power (watts))
Pp-m
9.54 dB
Difference
−5 dBm
Data Part Power = −25.46 dBm
(DatadBm = CntldBm + Pwrdiff)
Control Part Power = −35 dBm
Preamble
−30 dBm
(CntldBm = PredBm + Pp-m)
The message part power calculation is explained in the following section, “Message Part Power”.
Message Part Power
As stated earlier, the message part power (dBm) is comprised of the control part and data part power levels.
The message part power is calculated using the sum of the linear power values for DatadBm (data part power)
and CntldBm (control part power). Use the following formula to calculate the message part power:
10 Log[10(Data dbm / 10 + (-3)) + 10(Cntl dBm / 10 + (-3))]
By adjusting the two power levels, you can make the message power less than, equal to, or greater than the
preamble power. In some situations, the message part power can exceed the carrier power. When this occurs,
the ESG will automatically adjust its carrier power, up to its limits, to accommodate the new message part
power. The following examples demonstrate some of the ways you can set the message part power:
Example 1:
Preamble Power: -40 dBm
Pp-m: 5 dB
Ctrl Beta: 15
Data Beta: 0
This will result in a control part power level that is always 5 dB higher than the preamble therefore making
the message part power 5 dB higher than the preamble.
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Example 2:
Preamble Power: −40 dBm
Pp-m: 0 dB
Ctrl Beta: 0
Data Beta: 15
In this example the data part power will be 40 dB higher than the control part power. Since the Pp-m is set to
0 dB, this means that the control part power level is equivalent to the preamble power. This condition will
create a substantially higher message part power compared to the preamble power, and in most cases, this
would cause the carrier power to readjust itself to compensate for the high message part power.
Example 3:
Preamble Power: −40 dBm
Pp-m: −10 dB
Ctrl Beta: 15
Data Beta: 1
In this example the control part power is 10 dB less than the preamble power and the data part power is
-23.52 dB (beta of 1) less than the control part power. These settings result in a message part power that is
less than the preamble power.
Power Control Modes
The ESG gives you the opportunity to control your PRACH power using one of two methods, a Pp-m mode
or a Total mode. The mode selection is accomplished using the PRACH Power Setup Mode Pp-m Total softkey.
Pp-m Power Mode
The Pp-m mode lets you control the message part power by making changes to your control part and data
part power levels. The control part power level is adjusted by entering values in the Pp-m field. There is no
direct message part power adjustment in this mode since the Msg Pwr field is grayed-out (inactive).
However the message part power is shown in the grayed-out field. You can also calculate your message part
power by using the formulas given in the section, “Power Control” on page 465. Figure 16-10 shows the
Pp-m mode selection along with the two fields that were mentioned earlier.
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Figure 16-10
Pp-m Mode
Msg Pwr is Inactive
Pp-m is Active
Pp-m Power Mode Selected
Total Power Mode
The total mode lets you set the message part power directly, which in turn sets the control part power by
automatically adjusting the Pp-m value. In this mode, the Msg Pwr field is active and the Pp-m field is
grayed-out (inactive). To calculate what control part power and Pp-m value will result from a message part
power value, perform the following steps where
Pwrdiff = difference between relative power values
Cntlpwr = relative control power
Datapwr = relative data power
CntldBm = control part power
PredBm = preamble power
MessdBm = message power
1. Determine the difference between the relative power values.
Pwrdiff = Datapwr − Cntlpwr
2. Calculate the control part power.
CntldBm = MessdBm − 10 Log[1 + 10(Pwr diff / 10)]
3. Calculate the expected Pp-m value.
Pp-m = CntldBm − PredBm
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Figure 16-11 shows the selection of the total mode along with the two fields mentioned earlier.
Figure 16-11
Total Mode Selection
Msg Pwr is Active
Pp-m is Inactive
Total Power Mode Selected
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Generating a Single PRACH Signal
Using the single PRACH mode may turn the ESG ALC feature off. For reliable results, you may need to
perform a power search. Refer to “Special Power Control Considerations When Using DPCCH/DPDCH in
Compressed Mode or PRACH” on page 582 before completing this procedure.
The ESG is capable of transmitting a PRACH using the factory default channel parameters. This aspect of
the ESG is demonstrated in the following procedures.
Configuring the RF Output
1. Preset the ESG.
2. Set the carrier frequency to 1.95 GHz.
3. Set the carrier power to −10 dBm.
4. Turn on the RF output.
Selecting the PRACH and Single PRACH Modes
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Up.
2. Press Link Control > PhyCH Type > PRACH.
3. Press the PRACH Mode Single Multi softkey until Single is highlighted.
The factory default setting is the Single PRACH mode.
Selecting a Rear Panel Output Trigger
1. Press PRACH Rear Panel Setup > PRACH Output Signal Setup.
This sets up an output trigger signal at the EVENT 1 rear panel connector. Refer to “Configuring Rear
Panel Output Signals” on page 557 for more information.
2. Highlight the item under the Signal column that corresponds to Event1 under the Rear Panel
Ports Column.
3. Press More (1 of 3) > More (2 of 3) > PRACH Pulse (RPS23).
This will enable an output trigger that corresponds to the beginning of each PRACH.
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4. Press Mode Setup to return to the top-level real-time W-CDMA menu.
A default PRACH signal output has a single preamble and a message part with a 20 ms transmission time
interval (TTI). Setting the trigger output to occur on the PRACH pulse lets the spectrum analyzer or other
measuring equipment that is externally triggered, start its sweep at the beginning of the PRACH signal.
Generating the Baseband Signal
Press W-CDMA Off On to On.
Setting Up the E4440A PSA for the PRACH Signal
This procedure guides you through setting up the PSA for making a time domain measurement. Refer to
Figure 16-1 on page 459 for connecting the ESG to the E4440A PSA. Figure 16-12 on page 476 shows the
ESG output signal on the PSA display.
1. Preset the spectrum analyzer.
2. Select the W-CDMA mode.
Press Mode > W-CDMA.
3. Set the center frequency.
Press Frequency Channel > Center Freq > 1.95 > GHz.
4. Select the time domain measurement mode.
Press Measure > More 1 of 2 > Waveform (Time Domain).
5. Set a sweep time that shows the components of the PRACH transmission.
Press Meas Setup > Sweep Time > 50 > ms.
This sets 5 ms as the vertical time divisor (10 divisions x 5 ms = 50 ms)
6. Set the resolution bandwidth for a quick response time that captures the bursting nature of the PRACH
components.
Press Res BW > 500 > kHz.
7. Trigger the spectrum analyzer from the rear trigger input using the ESG’s PRACH pulse trigger signal.
Press Trig Source > Ext Rear.
8. Zoom in on the RF Envelope display.
Press Zoom.
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Figure 16-12
Displayed ESG Signal
Preamble
PRACH Message
PRACH pulse triggers
the beginning of the
PSA sweep
Modifying the PRACH Physical and Transport Layers
The tasks in this procedure build upon the previous procedure, “Generating the Baseband Signal” on
page 475.
The ESG lets you set many of the parameters that govern the PRACH transmission. This procedure guides
you through modifying some of these parameters for the physical and transport layers.
Modifying the Physical Layers
This task includes an example of setting up the preamble power ramp.
1. Press Link Control > PhyCH Setup > PRACH Power Setup.
2. Set the preamble power.
a. Move the cursor to highlight the Max Pwr field.
b. Press −20 > dBm.
This value is linked to the carrier signal power setting. When the W-CDMA format is first turned on,
the Max Pwr Field value changes to match the carrier signal power. It is a good practice to have
the W-CDMA format on prior to making adjustments to the PRACH power.
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3. Set the power ramp for multiple preambles.
a. Move the cursor to highlight the Ramp Step field.
b. Press 7 > dB.
This setting enables a power ramping when multiple preambles are used. Each successive preamble
transmission from the second to the last will increase in power by 7 dB.
4. Select the number of transmitted preambles.
a. Move the cursor to highlight the Num of Pre field.
b. Press 4 > Enter.
The number of transmitted preambles is now four, which means that the PRACH initial/starting power
level (first preamble) will be −41 dBm. The fourth preamble will be transmitted at the PRACH power
level set in step 2b or −20 dBm. This means the first three preambles will have power levels that are in
increments of 7 dB less than the fourth preamble. The initial power (first transmitted preamble power
level) is calculated as follows:
3 x 7 dB = 21 dB
NOTE
Figure 16-13
−20 dBm - 21 dB = −41 dBm initial power
When setting the Max Pwr, Ramp Step, and Num of Pre fields, they need to be done
in the order shown. If you do not set them in the order shown, errors may occur and values
may automatically change to accommodate limits.
Display After the Power Parameter Changes
5. Press Return > PRACH Timing Setup.
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6. Configure the distance from the beginning of one preamble to the beginning of the next preamble. This
is expressed in access slots.
a. Move the cursor to highlight the Tp-p (time period between preambles) field.
b. Press 2 > Enter.
7. Set the transmission time interval for the message part.
a. Move the cursor to highlight the TTI (transmit time interval) field.
b. Press 10 > msec.
8. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. You will not see a
change in the signal until you press this softkey.
Figure 16-14
Display After Time Parameter Changes
Modifying the Transport Layer
The transport channel (RACH) is available when the PRACH physical channel data type is set to TrCh
(factory default data type). This task teaches you how to make changes to the transport layer parameters.
1. Press Return > Return > Transport Setup > TrCH Setup.
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2. Set the data block size.
The block size and the number of blocks affect the bit rate into the transport layer. The data is punctured
or has bits added (rate matching) so that it fits into a frame for a given slot format. The Puncture field
currently displays a negative value. This indicates that bits will be added to the data in order to facilitate
rate matching. A positive value in this field means that puncturing will occur according to the percentage
shown. Figure 16-15 shows the location of the Max Puncture and Puncture fields.
a. Move the cursor to highlight the Blk Size field.
b. Press 450 > Enter > Apply Channel Setup.
The puncture rate has changed, because an increase in the block size increases the RACH data rate.
Figure 16-15 shows what the ESG display looks like once the transport channel parameters have been
set.
Figure 16-15
Display after Transport Layer Setup
Max Puncture
Puncture
Changing the PRACH Output Trigger
Press Return > Return > PRACH Rear Panel Setup > PRACH Output Signal Setup >
More (1 of 3) > More (2 of 3) > Message Pulse (RPS22) > Mode Setup.
This changes the triggering for the PSA so that the sweep starts at the beginning of the PRACH message
part.
You have now modified the PRACH physical and transport channel parameters. The PRACH will now
transmit four preambles with power stepping and the spacing/timing between each preamble (beginning of
one preamble to the beginning of the next preamble) was adjusted for two access slots. The message part
transmission has also been set to 10 ms. The RACH data rate was increased when the block size was
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adjusted. This resulted in the rate matching algorithm puncturing the data in order to fit it into a frame for the
given slot format.
Viewing the Modified PRACH Signal
This section uses the PSA settings from the procedure “Setting Up the E4440A PSA for the PRACH Signal”
on page 475.
The PSA time domain measurement mode lets you view many of the PRACH parameters, since they are
time dependent. Figure 16-16 shows the PRACH signal after the modifications from the previous section
“Modifying the PRACH Physical and Transport Layers” on page 476 have been completed. Notice the PSA
sweep starts at the beginning of the message part and the message part has a time interval of 10 ms (there are
5 ms per vertical division). This is the result of setting the ESG PRACH trigger to message pulse and the
preamble TTI field to 10 ms. You can also see the preamble power ramping.
Figure 16-16
Displayed ESG Signal
4 Preambles with Power Ramping
10 ms PRACH Message (TTI field)
PRACH Message
Trigger Starts the
PSA Sweep
21 dB
Generating the AICH for the PRACH Message Transmission
The tasks in this procedure build upon the previous procedure, “Modifying the PRACH Physical and
Transport Layers” on page 476. This procedure uses a different PSA connection diagram
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(Figure 16-17 on page 482) and base station connection diagram shown in the section, “Using the AICH
Feature with a Base Transceiver Station” on page 484.
Using the AICH feature may turn the ESG ALC feature off. For reliable results, you may need to perform a
power search. Refer to “Special Power Control Considerations When Using DPCCH/DPDCH in
Compressed Mode or PRACH” on page 582 before completing this procedure.
This procedure will teach you how to set up the AICH (acquisition indication channel) feature so that it
triggers the message part transmission. This procedure uses the ESG’s LF (low frequency) output to
simulate the AICH signal (TTL trigger), or if you prefer, an external source can be used. Connecting the
AICH trigger signal to the ESG requires the use of the rear panel AUX I/O connector. (See “Rear Panel
Overview” on page 16 or “Rear Panel Overview” on page 37 for more information on the AUX I/O
connector.) An adapter will be needed to make the connection between the LF OUTPUT and pin 17 on the
AUX I/O connector.
Finding the Rear Panel Input for the AICH Signal
1. Press Link Control > PRACH Rear Panel Setup > PRACH Input Signal Setup.
2. Find which rear panel connector accepts the AICH trigger.
The listed connector (Pattern trigger in 2 on AUX pin 17) is a pin on the AUX I/O connector.
Changing the PRACH Output Trigger
Press Return > PRACH Output Signal Setup > More (1 of 3) > More (2 of 3) > PRACH Pulse(RPS23).
This is being done so you can view the message part transmission on the PSA as the AICH is received. The
trigger output is on the EVENT 1 rear panel connector.
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Connecting the ESG
Refer to Figure 16-17 and make the connections as shown.
Figure 16-17
AICH Connection Diagram
Configuring the PRACH Message for the AICH Trigger
1. Press Mode Setup > Link Control > PhyCH Setup > PRACH Timing Setup.
2. Select AICH as the entry for the Message Part field.
a. Highlight the Message Part field.
b. Press Edit Item > AICH.
This sets up the PRACH signal so that the message part is not transmitted until an AICH trigger is
received. Since the ESG is not a receiver, it cannot receive and demodulate a true AICH signal, so
the input has to be a trigger signal.
3. Set the number of preambles to 1.
a. Highlight the Number of Preamble field.
b. Press 1 > Enter.
You can set the number of preambles in either the PRACH Power or PRACH Timing Setup display.
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Setting Up the LF Output as the AICH Signal
This task sets up the LF output so the results of the AICH trigger signal can be viewed on the PSA display
(see “Viewing the PRACH Message Using an AICH Trigger”). By following the steps in this task, the
message part will appear intermittently after each displayed preamble as the AICH trigger is received.
1. Press LF Out > LF Out Source > Function Generator.
2. Press LF Out Waveform > More (1 of 2) > Pulse.
3. Press LF Out Period > 21 > msec.
4. Press LF Out Width > 1 > msec.
5. Press LF Out Amplitude > 5 > Vp.
6. Press LF Out Off On to On.
Viewing the PRACH Message Using an AICH Trigger
This procedure guides you through configuring the PSA for making a spectrum analysis measurement. This
is being done to familiarize you with the different measurement modes that exist for the PSA. You could use
the W-CDMA mode, time domain measurement, to achieve the same results.
1. Preset the spectrum analyzer.
2. Select the spectrum analysis mode.
Press Mode > Spectrum Analysis.
3. Set the center frequency to 1.95 GHz.
Press Center Freq > 1.95 > GHz.
4. Set the span to zero hertz for close-in viewing of the PRACH signal.
Press Span > 0 > Hz.
5. Set the sweep time to 50 ms.
Press Sweep > Sweep Time > 50 > ms.
6. Set the spectrum analyzer to trigger from the ESG’s PRACH pulse trigger signal.
Press Trig > Ext Rear.
You now see the message part moving across the display as the AICH trigger is received after each
preamble. Figure 16-18 shows the message part as it appears after the third preamble transmission.
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Figure 16-18
Displayed ESG Signal
Preambles
PRACH Message—AICH Received
Using the AICH Feature with a Base Transceiver Station
Figure 16-19 shows the AICH feature connection with the AICH being provided by the base station. While
the ESG cannot demodulate an actual AICH signal, the base transceiver station can be configured to output
a TTL trigger signal that is timed with the AICH transmission. This trigger signal can then be used as the
AICH trigger for the ESG to transmit its message part. Or if you prefer, you can follow the instructions
shown in “Setting Up the LF Output as the AICH Signal” on page 483, and use the ESG’s LF output as the
AICH trigger source.
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Figure 16-19
Base Transceiver Station AICH Connection Diagram
1. Connect the ESG to the base transceiver station as shown in Figure 16-19.
2. Configure the base transceiver station to output a simulated AICH (TTL trigger) signal.
3. If you need a trigger signal from the ESG to determine when it transmits the PRACH, follow the
instructions in the section, “Changing the PRACH Output Trigger” on page 481.
4. Set up the ESG to expect the AICH trigger by following the instructions in the section, “Configuring the
PRACH Message for the AICH Trigger” on page 482.
5. Turn on the W-CDMA format.
6. Setup the ESG carrier signal.
7. Turn on the ESG RF output.
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Multiple PRACH Overview
The multiple PRACH feature of the ESG lets you simulate multiple UEs (user equipment/mobile)
attempting to contact a base transceiver station (BTS). This feature is especially beneficial for BTS overload
testing when multiple ESGs are used (see “Overload Testing with Multiple PRACHs—Multiple ESGs” on
page 509). The following is a list of some of the characteristics you will find in the multiple PRACH feature:
•
80 ms transmission/time period with access slot resolution
•
60 access slots (80 ms / 1.33 ms = 60) numbered 0 to 59
•
transmission simulation of eight UEs using independent signatures that automatically assigns the
channel codes in accordance with the 3GPP TS 25.213
•
transmission of an individual UE’s PRACH multiple times (up to 8 times) within the 80 ms time period
The number of times a UE’s PRACH can be transmitted is dependent on the number of access slots each
PRACH occupies.
•
incorporate AWGN (additive white Gaussian noise) with the multiple PRACH transmission
•
transmit the preamble or the preamble plus the message part
•
synchronize multiple ESGs to increase the number of UEs/PRACHs
Understanding the 80 ms Transmission/Time Period
The multiple PRACH feature incorporates an 80 ms time period in which to transmit the multiple
PRACHs/UEs. This 80 ms period has access slot resolution, so it contains 60 selectable access slots (0–59).
The entire 80 ms period is transmitted each time, even if only one access slot is utilized. Within this 80 ms
period you have eight available UEs. All eight can be active at the same time, and each UE has the capability
of transmitting its PRACH up to eight times. Figure 16-20 shows the 80 ms period display.
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Figure 16-20
Timing Setup Display
Clears all Access
Slots from the Row
where an Item is
Highlighted
Eight
UEs
Preamble Signatures
Eight Assignable Access Slots
Per UE within the 80 ms Period
The First Position is Assigned
Access Slot Zero as the Factory Default
However a single UE retransmission of its PRACH cannot overlap its previous PRACH transmission within
the same 80 ms period. For example, if UE1’s PRACH is 11.5 access slots long and its first PRACH
transmission starts in access slot zero, then the second PRACH transmission for UE 1 must start, at a
minimum, in access slot 12. If it was configured to begin in access slot 11, the second transmission would
not occur because slot 11 is partially occupied by the first PRACH transmission. But different UEs can
transmit in access slots occupied by other UEs. Figure 16-21 illustrates an example of when a PRACH
retransmission for the same UE is ignored. It also demonstrates how PRACHs can occupy the same access
slots when they are transmitted by different UEs.
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Figure 16-21
Transmitting PRACHs
If a third PRACH transmission was configured that overlapped the second PRACH transmission for UE1,
the third transmission would occur because the second transmission is ignored/not transmitted.
The multiple PRACH feature is configured from the factory to have UE 1 on and set to start in access slot
zero. This is so you can have a PRACH signal just by turning on the W-CDMA format and the RF output,
assuming that the MOD Off On hardkey is set to on (MOD ON annunciator is showing in the display).
In accordance with the 3GPP standards, there are 16 different signatures to choose from for each UE, and the
different signatures point to the appropriate channel codes for the control part and data part. These codes are
automatically selected when a signature is chosen and are listed in the ChCode Ctl Dat column. The
control part is always spread with the channelization code of spread factor 256. The spread factor for the
data part is determined by the slot format, but the node that the channelization code resides on is determined
by the signature.
As seen in Figure 16-20, there are eight positions per UE for assigning access slot numbers. When a position
has not been assigned an access slot, a dash is showing. If all eight positions have dashes, this has the same
affect as turning the UE off. This is because there are no PRACHs to transmit for the UE. You can transmit
eight PRACHs per UE by transmitting only the preamble. Since a preamble only occupies one access slot,
there would be no overlapping of the PRACH transmissions for an individual UE.
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There are multiple ways the ESG can trigger external measurement equipment for measuring the multiple
PRACH signal. Some examples of these are shown in the following list:
80 ms frame pulse This coincides with the frame boundaries for SFN mod 8=0.
10 ms frame pulse This denotes the SFN frame boundaries.
Preamble pulse
This indicates the beginning of the access slot for each preamble transmission.
Message pulse
This signifies the start of an access slot where the message part is being transmitted.
PRACH pulse
This denotes the access slot boundaries between PRACH repetitions.
Refer to “PRACH Mode” on page 572 for more information on trigger signals.
Understanding the Power Offset Between the Carrier and the Multiple PRACH
The ESG has an 18.06 dB offset between the ESG carrier power and the multiple PRACH power level. This
offset is shown by the PRACH power level in the PRACH Power Setup display. This is demonstrated in
Figure 16-22 where the carrier power is 0.0 dBm and the PRACH power is −18.06 dBm
(0.0 dBm − (−18.06 dBm) = 18.06 dB offset). Since the data part power has been turned off, the PRACH
power is shown in both the Max Pwr field (preamble power) and the Msg Pwr field (message part power)
as indicated in the figure.
Figure 16-22
Offset Power
ESG Carrier Power
PRACH Power—18.06 dB Offset from Carrier Power
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The offset is provided so the ESG can accommodate the additional power needed as more UEs (user
equipment/mobiles) are utilized. This offset remains constant on the ESG display regardless of the number
of UEs activated or parameter changes. However with the AWGN feature on, the addition of noise to the
PRACH signal will increase the offset. When this condition occurs, the ESG carrier power will remain
constant and the PRACH power level will decrease. This is demonstrated in Figure 16-23 where the AWGN
feature is on with a C/N value of 0.0 dB.
Figure 16-23
Offset Power with Noise Added
ESG Carrier Power
PRACH Power—22.77 dB Offset from Carrier Power
This offset will not create any problems with the multiple PRACH transmission. The typical test that utilizes
a multiple PRACH feature is used to discern a single PRACH transmission from among a group of PRACH
signals. The PRACH power values shown on the ESG display are valid and will be reflected in your
measurements, even when all UEs are on. They are also used to calculate the various other parameters like
the control part and data part power levels.
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Setting Up a Multiple PRACH Signal
The ESG automatically turns off the ALC (automatic leveling control) when the multiple PRACH mode is
selected. This is due to the bursting characteristics of the PRACH signal that causes rapidly varying power
levels. This situation is compounded in the multiple PRACH mode where you have multiple PRACH bursts
occurring, so the ESG ALC cannot maintain a constant power level. A manual power search can be
performed by pressing the Apply Channel Setup softkey. Refer to “Special Power Control Considerations
When Using DPCCH/DPDCH in Compressed Mode or PRACH” on page 582 for more information.
The procedure, “Selecting the PRACH and Multiple PRACH Modes” on page 492, shows you how to
access the W-CDMA modulation format. However most of the other procedures start from the first-level
W-CDMA softkey menu, which is shown in Figure 16-24. In this way, each procedure can stand alone
without regard to steps performed in other sections.
Figure 16-24
First-Level W-CDMA Softkey Menu
By following the procedures in this section, you will learn how to setup a basic multiple PRACH signal. The
section, “Viewing a Multiple PRACH Signal” on page 507, shows the output of the ESG using the
parameters set in each of the following procedures.
Configuring the RF Output
1. Preset the ESG.
2. Set the carrier frequency to 1.95 GHz.
3. Set the carrier power to −10 dBm.
4. Turn on the RF output.
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Selecting the PRACH and Multiple PRACH Modes
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Up.
This selects the W-CDMA uplink mode which resides in the first-level W-CDMA softkey menu.
2. Press Link Control > PhyCH Type > PRACH.
3. Press the PRACH Mode Single Multi softkey until Multi is highlighted.
This softkey menu level provides you access to other menus that control the PRACH signal. You can
access a menu that enables you to choose the reference block size for the transport channel, access the
rear panel input/output signal selections, determine input trigger signal parameters, and access the
physical and transport channel set up tables/menus. Figure 16-25 shows this softkey menu level with the
multiple PRACH mode selected.
Figure 16-25
Multiple PRACH Mode Selection
Multiple PRACH
Mode Selected
Access Rear Panel
I/O Signal Setup
Summary Display Continuously Shows the Current
PRACH Power Levels for the Various PRACH Components
Selecting the Rear Panel Output Trigger
1. Press PRACH Rear Panel Setup > PRACH Output Signal Setup.
This sets up an output trigger signal at the EVENT1 rear panel connector. Refer to “Configuring Rear
Panel Output Signals” on page 557 for more information.
2. Highlight the item under the Signal column that corresponds to Event1 under the Rear Panel
Ports column.
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3. Press More (1 of 3) > More (2 of 3) > PRACH Pulse (RPS23).
This will enable an output trigger that corresponds to the beginning of each PRACH.
4. Press Mode Setup to return to the top-level W-CDMA menu.
Generating the Baseband Signal
Return to the first-level W-CDMA menu and turn the W-CDMA format on.
This step can be performed at anytime during the setup. The advantage of turning the format on before
setting up the signal, if you have a spectrum analyzer or some other measuring equipment connected, is you
can see the changes as they are made.
Configuring the PRACH Code Setup
In this procedure you will learn how to set the parameters for controlling the transmission for the various
components that make up the PRACH. In addition, you will set the parameters that control the PRACH
transmission as a whole. It is divided up into four tasks:
•
“Accessing the Code Setup Table” on page 493
•
“Controlling the PRACH Transmission” on page 494
•
“Setting the Control Part Parameters” on page 497
•
“Setting the Data Part Parameters” on page 498
Accessing the Code Setup Table
Press Link Control > PhyCH Setup > PRACH Code Setup.
This takes you into the table editor where you can set the parameters for the message part and preamble. You
can also set the number of transmissions for the PRACH configuration. The parameters set within this table
apply to all eight UEs.
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Figure 16-26
PRACH Code Setup Display
Configures
the PRACH
Configures the
Control Part
Controls the Spacing
Between the Preamble and
the Message Part
Configures the
Message Part
Configures the Data Part
Controlling the PRACH Transmission
1. Set the PRACH scramble code.
a. Highlight the Scrambling Code field.
b. Press 506 > Enter.
The range for this field is 0 to 8191.
The scrambling code, in conjunction with the preamble signature, is used to uniquely identify the
mobile. The same scrambling code number is used for both the preamble and message part. The base
station informs the UE which code to use.
2. Set the number of transmitted 80 ms periods.
This feature is used in connection with a trigger for starting the PRACH transmission. Use this feature
when you want to measure the PRACH transmission for a set number of cycles or you just want to start
the transmission using a trigger.
a. Highlight the Number of 80ms field.
b. Press Edit Item.
Two softkeys are now showing, Enter and Infinity. The Enter key is used when you want to enter a
finite number of 80 ms period repetitions. You can actually enter the desired number without
pressing the Edit Item softkey. The Enter softkey will appear once you start entering a value. The
Infinity selection lets the transmissions occur indefinitely once a trigger is received until it is
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terminated by some other means (RF is turned off, modulation of the carrier is turned off, or the
modulation format is turned off). To access the Infinity selection, you must press the Edit Item softkey.
c. Press 100 > Enter.
The range for a finite transmission is 1 to 2147447836 repetitions. However the transmission will not
be limited unless Trigger has been selected as the PRACH trigger source.
d. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new
parameters will not be applied to the signal until this softkey is pressed.
e. Press the PRACH Trigger Source Immedi Trigger softkey until Trigger is highlighted.
In order to transmit a limited number of 80 ms periods, you must set the PRACH signal for a manual
trigger operation. If the W-CDMA format is on when you select Trigger, the signal will transmit until
the value in the Number of 80ms field has been reached. Then the PRACH signal will terminate
and the RACH Trg annunciator will gray-out. This means that the PRACH signal is waiting for a
trigger to occur before another transmission can begin. This is shown in Figure 16-27. Notice that the
PRACH Trigger softkey has become active (no longer grayed out) when Trigger was highlighted.
Figure 16-27
PRACH (RACH) Trigger Annunciator
Waiting for
Trigger
Trigger Received
Softkey is now Active
f. Press the PRACH Trigger softkey.
The ESG is now transmitting 100 repetitions, entered in step 2c, of the current
80 ms period setup. The RACH Trg annunciator will gray-out after 100 repetitions have been
completed. To repeat the transmission, just press the PRACH Trigger softkey again.
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You will notice the PRACH Trigger Source Immedi Trigger and the PRACH Trigger are located on several
softkey menus. This was done so you could provide the trigger or make a different trigger choice without
having to return to any one particular menu. Pressing the PRACH Trigger softkey is a manual trigger
action. You can also provide an external trigger signal for the PRACH transmission.
3. Press the PRACH Trigger Source Immedi Trigger softkey until Immedi is highlighted.
The Immedi choice lets the W-CDMA signal transmission start as soon as the modulation format is
turned on. Since the format is already on, selecting Immedi will enable the immediate transmission of
the currently configured signal.
Configuring the Message Part Transmission
1. Choose whether or not to transmit the message part
a. Highlight the Message Part field.
b. Press the Edit Item softkey.
Two softkeys are displayed, ON and OFF. When you select OFF, the message part is not transmitted
leaving only the preamble as the PRACH transmission.
c. Press the ON softkey since we will be transmitting the PRACH with both the preamble and message
part.
2. Select the transmission time for the message part.
a. Highlight the TTI (transmit time interval) field.
b. Press 10 > msec.
There are two valid entries for this field, 10 or 20 ms. The values can be entered using decimal
notation (0.01 or 0.02 seconds) or millisecond units (10 or 20 ms).
The 10 ms setting equates to 7.5 access slots (one radio frame) and the 20 ms spans 15 access slots (two
radio frames).
If you need to have an individual PRACH (UE) repeat multiple times within the 80 ms time period, you
may want to use the 10 ms setting. Since you are limited to 60 access slots (80 ms), the 20 ms setting will
decrease the number of times a UE’s PRACH can be retransmitted within the 80 ms time period.
3. Enter the number of access slots from the preamble to the message part (Tp-m).
The number of access slots starts from the beginning of the preamble and ends at the beginning of the
message part. Figure 16-28 shows a PRACH with a Tp-m of 3 access slots.
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Figure 16-28
Tp-m Setting
Message Part
10 ms TTI
a. Highlight the Tp-m (time from the preamble to the message part) field.
b. Press 4 > Enter.
The range for this field is 1 to 15.
You have now increased the distance from the for the Tp-m from three access slots (3.99 ms) to four
(5.32 ms). An access slot is 1.33 ms in length.
If you need to have a UE repeat its PRACH multiple times within the 80 ms time period, you may want
to keep the Tp-m to a minimum value. Since you are limited to 60 access slots (80 ms), an increase in the
Tp-m value further limits the number of times a UE’s PRACH can be repeated.
4. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. You will not see a
change in the signal until you press this softkey.
Setting the Control Part Parameters
1. Select the message part control data.
a. Highlight the Msg-Ctrl Data field.
b. Press Edit Item.
Notice that you have a selection of different control information types with the factory default being
3GPP STD (pilot bit pattern as stated in the 3G TS 25.211 V3.3.0 (2002-03). You can select a PN
sequence, FIX 4 pattern, or create your own control pilot information with the User File selection.
c. Ensure that 3GPP STD is highlighted and press Return.
2. Set the TFCI (transport format combination indicator) bits.
a. Highlight the TFCI Pattern field.
b. Press Edit Item.
Notice that you have a selection of different TFCI patterns that you can choose from, including the
ability to create your own pattern (User File softkey). The base station uses the TFCI to determine
what transport channel configuration is being used. The TFCI pattern, relative to a transport channel
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configuration, is determined by the base station network; it is not defined by the 3GPP standards. If
the message part TTI is 20 ms, the TFCI is repeated in the second radio frame (each radio frame is
10 ms in length).
c. Press PN Sequence > PN9.
3. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new
parameters will not be applied to the signal until this softkey is pressed.
Setting the Data Part Parameters
1. Set the data type for the data part.
a. Highlight the Msg-Data Data field.
b. Press Edit Item.
Again you can see that you are provided different choices for the data type. The transport channel
selection (factory default) utilizes the RACH (random access channel) which gives you greater
flexibility in controlling the data parameters such as the data rate (setting block size), CRC size, and
puncture rate.
c. Press the Transport CH softkey as the data selection type.
The softkey menu level, where PRACH was selected as the channel type, gives you access to the
transport channel table editor where you can set its parameters.
2. Select the message part slot format.
a. Highlight the Slot Format field.
Note the 60 ksps symbol rate (factory default) shown in the Symbol Rate field.
b. Press 1 > Enter.
You have a choice of slot formats: 0, 1, 2, and 3. Notice that the symbol rate changed to 30 ksps.
Remember that the symbol rate is controlled by the slot format.
As seen in step b above, you can adjust your symbol rate by changing the value in the Slot Format
field. Conversely, you can adjust your slot format by using the Symbol Rate field.
Each 10 ms message part period is subdivided into 15 slots and the slot format determines the attributes
for them. Each format is defined in the 3GPP standards.
3. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new
parameters will not be applied to the signal until this softkey is pressed.
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Figure 16-29 shows the PRACH code setup display after all tasks within this procedure have been
completed.
Figure 16-29
PRACH Code Settings
Configuring the PRACH Power Setup
In this procedure you will learn how to set the various power levels used in a PRACH transmission. Within
the power setup menu there are two modes to choose from, Pp-m and Total. This procedure uses the Pp-m
mode. The PRACH power has two parts, the preamble and the message part. Further, the message part is
comprised of two other powers, control part and data part powers. For more information on PRACH power
control and modes, see “Power Control” on page 465 and “Power Control Modes” on page 471.
Notice as you make changes to the different power settings, the message part power
(grayed -out Msg Pwr field) also changes.
Accessing the PRACH Power Setup Display
Press Link Control >PhyCH Setup > PRACH Power Setup.
This takes you into the table editor where you can set the power parameters for the message part and
preamble. The parameters set within this table apply to all eight UEs.
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Figure 16-30
PRACH Power Setup Display
Pp-m Power Mode Selected
Controls the Control Part Power
Controls the Preamble Power
Controls the Data Part Power
Setting the Preamble Power
1. Highlight the Max Pwr field.
2. Press −30 > dBm.
Notice that the carrier power has changed. The carrier power will always be 18.06 dB above the PRACH
power. See “Understanding the Power Offset Between the Carrier and the Multiple PRACH” on page 489
for more information on the power offset.
Adjusting the Control Part Power
1. Highlight the Pp-m field.
2. Press 5 > dB.
The control part power is set with respect to the preamble power level. The Pp-m value is used to adjust the
control part power level. Do not confuse this as setting the message part power
5 dB above the preamble. It is the combination of the control part and the data part power that determine the
message part power. However, since the control part is now 5 dB higher than the preamble, the message part
power cannot drop below the level of −25 dBm (preamble power of −30 dBm + 5 dB Pp-m)
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Configuring the Data Part Power
1. Set the control power level to zero dB.
a. Highlight the Ctrl Beta field.
b. Press 15 > Enter.
You are now using the control part power as the 0 dB reference for the data part power. This means that
the −25 dBm control part power set in the “Adjusting the Control Part Power” task, is now the zero dB
reference for the data part power that will be set in step 2. Changes to the Ctrl Pwr or the Ctrl Beta
fields does not affect the control part power level; it only sets a reference level for the data part power.
2. Set the data part power relative to the control part power.
a. Highlight the Data Beta field.
b. Press 5 > Enter.
You have now set the data part power to be 9.54 dB lower than the control part power. A beta of 5
equates to −9.54 dB. Since the data part power is less than the control part power, you will notice that the
message part power is approximately 5 dB higher than the preamble power level. This indicates that the
message part power is dominated by the control part. If you set both data the part and control part
relative powers to 0.0 dB (equal data part and control part power levels or double the control part
power), you will see a
3 dB increase in the message part.
Figure 16-31 shows the PRACH power setup display after all tasks within this procedure have been
completed.
Figure 16-31
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Configuring the PRACH Timing Setup
In this procedure you will learn how to enable multiple UEs/PRACHs and align them within the access slots.
You have eight available UEs that can span an 80 ms time period (60 access slots numbered 0 to 59). The
UEs can be configured so their PRACHs occupy the same or different access slot(s) relative to other UEs.
Each UE can also be configured to transmit its PRACH up to eight times using different access slots.
NOTE
The number of times a single UE can transmit its PRACH within the 80 ms time period is
constrained by the number of access slots a single PRACH occupies. If the UE retransmits
in a timeslot that is occupied by one of its previous PRACH transmissions, the
retransmission does not occur.
However you will have to turn the message part off to achieve the maximum number of individual UE
PRACH transmissions.
All eight UEs can be active at the same time and each can have a different or the same signature assignment.
For more information on understanding the PRACH Timing Setup display, see “Understanding the 80 ms
Transmission/Time Period” on page 486.
Accessing the PRACH Timing Setup Display
Press Link Control > PhyCH Setup > PRACH Timing Setup.
This takes you into the table editor where you can set the number of UEs for transmitting multiple PRACHs.
For the factory default setting, UE1 is on and the starting access slot in position one for all UEs is zero.
The parameters set in this table apply to the UE selected, unlike the other setup displays where the
parameters apply to all eight UEs.
For the following tasks, we will work with three UEs. This will demonstrate how different UEs can occupy
the same access slots, and how to repeat/retransmit a UE’s PRACH.
Figure 16-32 on page 506 shows a graphical representation of the multiple PRACH transmission as
configured by this procedure, while Figure 16-33 on page 508 displays the same signal configuration on the
E4440A PSA.
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Activating the UES
This task assumes the factory preset conditions for the timing setup table. The desired UEs can be turned off
or on at any time during your signal setup.
1. Turn on UE2 and UE4.
a. Highlight Off for UE2 in the On/Off column.
b. Press the Edit Item softkey.
Each press of the Edit Item softkey turns the UE on or off.
c. Repeat steps a and b for UE4.
Setting the Preamble Signature
The signature is used by the base station to identify which UE it is communicating with. This task assumes
the factory preset conditions for the timing setup table.
1. Set the UE1 preamble signature to five.
a. Highlight the Signature field that corresponds to UE1.
b. Press 5 > Enter.
The range for this field is 0 to 16.
2. Set the UE2 preamble signature to seven.
a. Highlight the Signature field that corresponds to UE2.
b. Press 7 > Enter.
3. Set the UE4 preamble signature to zero.
a. Highlight the Signature field that corresponds to UE4.
b. Press 0 > Enter.
Configuring Access Slots
When transmitting multiple PRACHs for the same UE, they cannot occupy any of the same access slots
within the 80 ms period. If they do, the subsequent (second PRACH, etc.) PRACH transmission that uses
any of the same access slots will not be occur.
There are two ways to enter the access slot number within the timing setup table:
•
Enter the access slot number using the numeric keypad and press the Enter softkey.
•
Press the Edit Item softkey, enter the number using the numeric keypad, and press Enter.
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Access slot numbers can be entered into positions that either contain dashes or that already contain an access
slot number.
Conversely there are also two ways to eliminate access slot numbers:
•
Highlight the position for a UE that contains the unwanted access slot within the 80 ms time period.
Press the Edit Item softkey and then the Off softkey that appears.
You will see a dash inserted in place of the access slot number. The dash means that the current position
within the 80 ms period has been turned off.
•
Highlight any position/item on a UE’s row, and press the Clear All Pos of Selected UE softkey.
You will see a dash inserted in place of all access slot numbers for the selected UE.
When all positions for a UE are occupied by dashes, the UE can no longer transmit any PRACHS. This has
the same affect as turning off the UE.
In this task you will learn how to use access slots for determining the placement of the PRACHs within the
80 ms time period.
This task assumes factory preset conditions for the timing setup display.
1. Setup UE1 for two PRACH transmissions.
For this task, we will use the factory default access slot of zero for the first UE1 PRACH transmission.
Using the parameters that can be set in the PRACH code setup display, you can calculate the number of
access slots required for each UE1 PRACH transmission. This calculated value can then be used to
determine the placement for each repeated PRACH within the 80 ms period. This avoids overlapping the
retransmitted PRACHs. Remember a PRACH that is repeated and overlaps a previous transmission for
the same UE, is ignored.
In the section, “Configuring the PRACH Code Setup” on page 493, we set the Tp-m to 4 access slots and
the message part TTI to 10 ms (7.5 access slots). These values are used in the following steps to
determine the access slot for the second UE1 PRACH transmission.
a. Highlight the second access slot position for UE1.
b. Calculate the number of access slots occupied by a single PRACH.
Message part TTI = 10 ms
One access slot = 1.33 ms
10 ms / 1.33 ms = 7.5 access slots
Tp-m = 4 access slots
One PRACH transmission = 7.5 + 4
= 11.5 access slots
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The second PRACH transmission will need to begin, at a minimum, in the 12th access slot (access
slot number 11 (0 + 11 = 11)). If you started the second transmission in access slot 10, it would be
ignored since the first transmission occupies part of that access slot.
In order to clearly show the second UE1 PRACH transmission on the PSA, we will select an access
slot that will not be occupied by other UEs that are configured later in this task.
c. Press 15 > Enter.
2. Configure UE2 for a single PRACH transmission starting in access slot 2.
a. Highlight the first access slot position for UE2.
b. Press 2 > Enter.
This PRACH will start its transmission between the first preamble for UE1 and its message part. The
message part for UE2 will begin during the first message part for UE1. For the length of time that the
message part for UE1 and UE2 occupy the same access slots, they will be additive creating a stronger
signal during that time period.
3. Leave UE4 to transmit a single PRACH starting in access slot 0.
This PRACH will occupy the same access slots as the first PRACH transmission for UE1. UE1 and UE4
will be additive during this transmission time period creating a higher signal level for the same period of
time.
4. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. You will not see a
change in the signal until you press this softkey.
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Figure 16-32 shows both the completed timing setup display and a graphical representation of the setup by
access slot when this procedure was used to configure the multiple PRACH signal. Figure 16-33 on
page 508 shows the output of the ESG, with the same configuration, on the Agilent E4440A PSA Spectrum
Analyzer.
Figure 16-32
Multiple PRACH Timing Setup
Timing Settings
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Viewing a Multiple PRACH Signal
This procedure uses the Agilent E4440A PSA Spectrum Analyzer for measuring the ESG output. Figure
16-1 on page 459 shows the connections between the ESG and the PSA. The signal shown in Figure 16-33
on page 508 was built using the procedures from the section “Setting Up a Multiple PRACH Signal” on
page 491. If you have used other parameters, your signal output may show different characteristics.
1. Preset the spectrum analyzer.
2. Select the Spectrum Analysis mode.
Press Mode > Spectrum Analysis.
3. Set the center frequency.
Press Frequency Channel > Center Freq > 1.95 > GHz.
4. Select the zero Hertz span.
Press Span > Zero Span.
This sets the PSA to function like an oscilloscope measuring in time rather than frequency.
5. Set the sweep time to 80 ms.
Press Sweep > 40 > ms.
6. Set the resolution bandwidth for a quick response time that captures the bursting nature of the PRACH
components.
Press BW/Avg > 8 > MHz.
Whenever you make a measurement in the zero Hertz span, you need to set the resolution bandwidth to
its maximum value to ensure capturing all of the signal characteristics.
7. Trigger the spectrum analyzer from the rear trigger input using the ESG trigger signal selected in the
section, “Selecting the Rear Panel Output Trigger” on page 492.
Press Trig > Ext Rear.
8. Set the PSA to average the signal measurement.
Press Det/Demod > Detector Auto Norm > Average.
9. Lower the reference level to −10 dBm.
Press Amplitude Y Scale > Ref Level > 10 > -dBm.
10. Resolve the display for a closer view of the signal.
Press Scale/Div > 5 > dB.
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11. Remove the Scale/Div 5.00 dB text from the display.
Press the ESC hardkey.
Figure 16-33
Transmitted Multiple PRACH Signal
Message Part for UE1, UE2,
and UE4 Added Together
Message Part for UE1
and UE4 Added Together
Remaining UE2 Message Part
Preamble for UE1
and UE4 Added Together
UE1 Second PRACH Transmission
Preamble for UE2
Connecting the ESG to a Base Station
1. Connect the ESG to the base station as shown in Figure 16-2 on page 460
2. Configure the base station to receive the multiple PRACH signal.
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Overload Testing with Multiple PRACHs—Multiple ESGs
With the advanced feature of transmitting multiple PRACHs, you can perform base transceiver station
overloading using two ESGs. This gives you the capability of transmitting up to 16 UEs. When the Frame
Sync Trigger signal is used for both ESGs, they will synchronize to within one chip of the base station frame
synchronization signal. When ESG 2 is synchronized using the ESG Sync Pulse signal, you may experience
an additional half chip delay from ESG 2. Figure 16-34 shows the multiple ESG setup and Table 16-2 list the
signals shown in the drawing and their respective ESG rear panel connections.
Figure 16-34
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Multiple ESG Setup
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Table 16-2
Multiple ESG I/O Signals and Connections
Signal
Signal Type
Rear Panel
Connector
Input
10 MHz Reference
10 MHz IN
This ensures that both ESG’s timebase are phase
aligned with the BTS reference.
Frame Sync Trigger
PATT TRIG IN
This aligns the ESG’s frame timing with the BTS. This
ensures that the BTS can detect the beginning of a
PRACH signal radio frame.
PRACH Start Trigger
BURST GATE IN
This is the trigger signal for ESG 1 to begin its
PRACH transmission.
ESG Sync Pulse (only for ESG 2)
PATT TRIG IN
This signal lets ESG 2 synchronize with the BTS
through ESG 1. This is used if the Frame Sync Trigger
cannot be split between the two ESGs. This may cause
an additional one half chip delay in ESG 2.
PRACH Start Trigger Echo Back (only for
ESG 2)
BURST GATE IN
This signal triggers ESG 2 to start its PRACH
transmission. The PRACH Start Trigger signal can be
used in place of this signal, if it has the power
available to split between the two ESGs. If the
PRACH Start Trigger signal is used, ESG 2’s
synchronization source must be set to the same source
as ESG 1.
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Table 16-2
Multiple ESG I/O Signals and Connections
Signal
Signal Type
Rear Panel
Connector
Output
ESG Sync Pulse (only for ESG 1)
EVENT 1
This is a replacement for the BTS Frame Sync signal
for ESG 2, if the BTS signal does not have the power
capability to split between two ESGs.
PRACH Start Trigger Echo Back (only for
ESG 1)
EVENT 2
This signal is used to synchronize the beginning of the
PRACH transmission between the two ESGs. It
triggers ESG 2 to start its PRACH transmission.
All of the I/O signal connectors can be identified using the softkeys accessed by the PRACH Rear Panel Setup
softkey. While the input signals are fixed to specific connectors, the output signals can be configured for
various rear panel connectors. In this procedure, the connectors listed in Table 16-2 are used.
If your BTS does not have the available power for splitting the frame synchronization signal between both
ESGs, ESG 1 can produce a synchronization signal for ESG 2. In this way, ESG 2 is synchronized with the
BTS through ESG 1. This is done by using the sync pulse signal from ESG 1. If your BTS does have the
power capability for splitting the frame synchronization signal between two ESGs, then the ESG sync pulse
signal is not required.
If more than 16 UEs are required, you can connect additional E4438Cs using the ESG’s PRACH start and
sync signal features to coordinate the synchronization and start triggers. For example, if a third ESG was
needed, you would follow the connections shown in Figure 16-34 on page 509 and the configuration
instructions in the following sections for ESG 2, and apply them to ESG 3.
The versatility of the ESG lets you configure the PRACH start trigger using a LF (low frequency) output
signal. The LF output can be configured for a pulse or square-wave, or you can use an external source. The
following multiple ESG procedure uses the ESG’s LF output as the trigger source.
Connecting the ESG to the Base Transceiver Station
Connect the equipment as shown in Figure 16-34 on page 509 and listed in Table 16-2 on page 510.
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Configuring the ESGs
1. Set up the multiple PRACH signal for both ESG 1 and ESG 2 using the procedures from “Setting Up a
Multiple PRACH Signal” on page 491. However, set each UE to a different signature, and turn on all
UEs.
You can vary the parameters between ESG 1 and ESG 2 for the multiple PRACH signals to obtain your
desired output.
2. Configure ESG 1 rear panel output trigger signals according to Table 16-2 on page 510.
3. Select the ESG input synchronization signal type.
a. On ESG 1, press Link Control > PRACH Trigger Setup > Frame Trigger Setup >
Sync Source SFN FClk ESG to FClk.
b. On ESG 2 press Link Control > PRACH Trigger Setup > Frame Trigger Setup >
Sync Source SFN FClk ESG to FClk or to ESG if you are using the ESG sync pulse signal.
This lets the ESG synchronize using the BTS frame clock signal. The ESG selection for ESG 2 enables
ESG 2 to synchronize with ESG 1. Since ESG 1 is synchronized with the BTS, this means that ESG 2
will also be synchronized with the BTS through ESG 1. The Frame Trigger Setup softkey can also be
accessed from the top level W-CDMA softkey menu.
4. Set the frame synchronization trigger mode.
a. On ESG 1, press Frame Sync Trigger Mode Single Cont to Cont.
b. On ESG 2, press Frame Sync Trigger Mode Single Cont to Cont.
The single mode (Single) lets the ESG trigger off the first BTS frame pulse and ignores all subsequent
frame timing pulses. The continuous mode (Cont) enables the ESG to align its frame timing with each
BTS frame timing pulse.
5. Set the frame timing pulse interval.
a. On ESG 1, press Frame Clock Interval > 10 msec, 20 msec, 40 msec, 80 msec, or 2560 msec.
b. On ESG 2, press Frame Clock Interval > 10 msec, 20 msec, 40 msec, 80 msec, or 2560 msec.
The actual frame timing interval value is dependent on the BTS frame clock pulse interval and whether
or not the ESG frame synchronization trigger mode is set to single or continuous. If the ESG trigger
mode is continuous, then it is critical that the selection is a value that is less than or equal to the base
station frame pulse interval, or else the ESG will incur an out of synchronization condition with the BTS.
When this occurs, an Out Sync annunciator appears on the ESG. For example, if the BTS frame timing
was 20 ms and the ESG selection was 40 msec, an out of synchronization condition will occur. The
results of the example are shown in Figure 16-35. An ESG frame clock interval of 10 or
20 ms will resolve the out of sync condition. This applies to ESG 1 and ESG 2 if they are both directly
connected to the BTS frame timing interval signal. However, if ESG 2 is synchronized using the ESG
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Sync Pulse signal from ESG 1, then its frame interval selection, if incorrect, may cause only a temporary
out of synchronization condition that is self-corrected. This is because ESG 2 is synchronized with ESG
1 and not directly with the BTS. See “PRACH Synchronization” on page 578 and “Frame Sync Trigger
Status Indicator” on page 579 for more information.
Figure 16-35
Out of Synchronization Annunciator
Out of Sync
Annunciator
6. Press Return > Return > PhyCH Setup > PRACH Trigger Source Immedi Trigger to Trigger.
Using the task, “Controlling the PRACH Transmission” on page 494, you can set the number of 80 ms
period repetitions for a finite number of PRACH transmissions, or using the infinity selection, you can
enable a continuous PRACH transmission once the PRACH start trigger is received by the ESG.
NOTE
In order to have a finite number of transmitted 80 ms periods, you will need to ensure that
the PRACH trigger source is disabled once the PRACH transmission starts. If the trigger
source is not disabled, the PRACH signal will retrigger after the entered number of 80 ms
periods are transmitted.
Figure 16-36 shows the frame trigger menus after all selections have been completed. Your selection for the
Frame Clock Interval may be different than what is shown. If you have kept your PRACH trigger source
active, you will see the RACH Trg annunciator gray-out intermittently as the transmission from the trigger
expires and a new trigger is acquired.
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Figure 16-36
ESG 1 and ESG 2 Frame Timing Setup
ESG 1
Set to FClk
ESG 1 is Synchronized
with the BTS Timing
Signal
ESG 1 has Received the
PRACH Start Trigger
(will gray-out when a
trigger is required)
Set to Cont
ESG 2
Set to ESG
ESG 2 is Synchronized
with the ESG 1 Timing
Signal
ESG 2 has Received the
PRACH Start Trigger
(will gray-out when a
trigger is required)
Set to Cont
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Setting Up the LF Output as the PRACH Start Trigger Signal
While the equipment setup shows ESG 1 as providing the PRACH start trigger signal, the signal can be
provided by either ESG 1, ESG 2, or an external source. Perform the following steps for ESG 1:
1. Press LF Out > LF Out Source > Function Generator.
2. Press LF Out Waveform > More (1 of 2) > Pulse.
3. Press LF Out Period > 80 > msec.
This sets the trigger to occur every 80 msec.
4. Press LF Out Width > 8 > usec.
5. Press LF Out Amplitude > 3 > Vp.
Three volts was selected because the BURST GATE IN is a CMOS connection.
6. Press LF Out Off On to On.
Figure 16-37 shows how the LF output display looks after all the steps from this procedure have been
completed.
Figure 16-37
LF Output Setup
You now have two ESG output signals that are transmitting a combined total of 16 UEs. The BTS can be
configured to try and identify each individual PRACH or configured to identify an individual UE from
among the 16 transmitted PRACHs.
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DPCH
Generating a DPCCH/DPDCH with a Reference Measurement Channel
The tasks in this procedure teach you how to set up a pre-defined DPDCH reference measurement channel.
Configuring the RF Output
1. Preset the ESG.
2. Set the carrier frequency to 1.95 GHz.
3. Set the carrier power to −10 dBm.
4. Turn on the RF output.
Selecting a Reference Measurement Channel
The ESG provides a single-softkey solution for configuring the transport layer coding according to the
reference measurement channel’s (RMC) 3GPP specifications.
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Up.
2. Press Link Control > Ref Measure Setup > RMC 384 kbps (25.141).
3. Press PhyCH Setup > DPCH Power Setup.
4. Press Adjust Code Domain Power > Scale to 0dB.
This adjustment changes only the displayed power values, the I/Q channels are automatically adjusted to
achieve zero dB power. For more information on channel power, see “Adjusting Code Domain Power”
on page 560.
5. Press Mode Setup to return to the top level W-CDMA menu.
In this task you have selected a predefined 384 kbps reference measurement channel setup that conforms to
the 3GPP standards. For more information on reference measurement channels, see “Reference
Measurement Channels (RMC)” on page 562.
Generating the Baseband Signal
Press W-CDMA Off On to On.
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Configuring the E4440A PSA for Viewing the DPCCH/DPDCH Output
One of the features of the PSA is its ability to measure the occupied bandwidth of the input signal. Since this
feature requires minimal setup, it provides a quick way of viewing the input and making a measurement.
This procedure guides you through setting up an occupied bandwidth measurement.
1. Preset the spectrum analyzer.
2. Select the W-CDMA mode.
Press Mode > W-CDMA.
3. Select the mobile setup.
Press Mode Setup > Radio > Device BTS MS to MS.
4. Set the center frequency.
Press Frequency Channel > Center Freq > 1.95 > GHz.
5. Display the signal’s bandwidth.
Press Measure > Occupied BW.
Figure 16-38
Chapter 16
Displayed ESG Signal
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Modifying the DPCCH/DPDCH Physical and Transport Layers
Modifying the Physical Layer
The tasks in this procedure build upon the procedure, “Using the Transmit Power Control” on page 525.
1. Press Link Control > PhyCH Setup > DPCH Power Setup.
2. Modify the power level for the reference measurement channel.
a. Highlight the DPDCH Power field.
b. Press −5 > dB.
3. Press Adjust Code Domain Power > Scale to 0dB > Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new settings
are not be applied to the signal until this softkey is pressed.
You have now modified the DPDCH to have a −5 dB power level. Figure 16-39 shows the power setup
display with the new power value.
Figure 16-39
DPCH Power Setup Display
4. Change the symbol rate.
a. Press Return > DPCH Code Setup > DPCH DPCCH DPDCH to DPDCH.
b. Highlight Symbol Rate.
c. Press 480 > ksps > Enter.
The Symbol Rate and Slot Format fields are coupled. If you select a symbol rate that is too high for
the current slot format, this could cause over puncturing of the transport channel data. But since the
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symbol rate and slot formats are linked together, a change to one value will automatically adjust the
other when required.
5. Set the bit error rate ratio.
a. Highlight the TrCH BER Cycle field.
b. Press 125 > Enter.
The value entered composes a group of data bits that can contain a specified number of error bits,
which are entered in the following steps. If you enter zero for the TrCH BER Cycle field, this
effectively terminates the error bit insertion feature.
c. Highlight the TrCH BER ErrLen field.
d. Press 10 > Enter.
This sets the number of error bits contained in the group of data bits shown in the
TrCH BER Cycle field. The value ten means that ten of the 125-bits are error bits. The error bit
positions are randomly changed to prevent them from appearing in fixed positions and to ensure,
when multiple transport channels are used, that errors can appear across all data blocks. You can also
enter zero for no error bit insertion.
The value for the TrCH BER ErrLen cannot be greater than the value for the
TrCH BER Cycle. If you enter a greater value, the ESG will disregard the entered parameter and set the
field equal to the TrCH BER Cycle field setting.
The error ratio is calculated using the following formula:
BER = TrCH BER ErrLen / TrCH BER Cycle
Using the values entered above:
BER = 10 / 125
BER = .08 or 8%
The BER is shown in the grayed-out TrCH BER field. See Figure 16-40 for the location of the
BER fields.
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6. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new settings
are not be applied to the signal until this softkey is pressed.
You have now changed the DPDCH symbol rate and modified the transport channel bit error rate to
8 percent. Figure 16-40 shows the code setup display after making the changes.
Figure 16-40
DPCH Code Setup Display
Symbol Rate Field
BER Setup Fields
BER
Modifying the Transport Layer
Up to six transport data channels are available to the DPDCH when the DPDCH data type is set to TrCh
(factory default data type). This task teaches you how to make changes to the transport layer parameters
while maintaining an acceptable data puncture rate.
1. Press Return > Return > Transport Setup.
2. Press 3 > Enter to highlight/select channel 3.
3. Press TrCH State Off On to On.
4. Press TrCH Setup.
Refer to Figure 16-41. Notice the greyed out fields Max Puncture and Puncture. The Max
Puncture field shows the maximum amount of puncturing allowed for this transport channel and the
Puncture field shows the current puncture rate. A positive puncture value indicates the data is being
punctured while a negative value means that bits are added. The current puncture value exceeds the
allowable puncture rate of 60%. The excessive puncturing will be reduced when the rate matching
attribute is adjusted in one of the following steps.
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Figure 16-41
Excessive Puncturing
Max Puncture
Puncture
5. Select the encoder type.
a. Move the cursor to highlight the Coding field.
b. Press Edit Item > 1/3 Conv.
This will actually increase the puncturing slightly. This is because the encoding is changed from
1/2 convolutional encoding (one bit in, two bits out) to 1/3 convolutional encoding (one bit in, three
bits out).
6. Set the rate matching.
a. Move the cursor to highlight the Rate Match Attr field.
b. Press 256 > Enter.
Notice that the puncture rate is now reduced to an acceptable level.
7. Press Return > 2 > Enter > TrCH Setup.
Notice that the puncture rate for DCH 2 matches the maximum puncture rate. The puncture rate
increased when the parameters for channel three were modified. This can be adjusted by reducing the
block size.
8. Set the block size.
a. Move the cursor to highlight the Blk Size field.
b. Press 95 > Enter > Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new
settings are not be applied to the signal until this softkey is pressed.
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9. Press Return.
A third transport channel has been turned on and configured to use 1/3 convolutional encoding with a rate
match attribute of 256. Changing channel parameters can affect your puncture rate, and they may also affect
the parameters for other active channels. Whenever parameters are changed in one channel, check the other
channels to ensure their parameters are still within acceptable limits. Notice that decreasing the block size
for transport channel two lowered the data rate which in turn decreased the amount of data that would be
punctured. Puncturing can also be reduced by increasing the DPDCH symbol rate.
Configuring the E4440A PSA for Viewing Additive Noise
1. Select the spectrum analysis mode.
Press Mode > Spectrum Analysis.
2. Set the center frequency to 1.95 GHz.
Press Frequency > 1.95 > GHz.
3. Set the span to 10 MHz.
Press Span > 10 > MHz.
4. Average the signal for better viewing.
Press BW/Avg > Average On Off to On.
5. Remove text showing average value from the display.
Press ESC.
Adding Noise
The tasks in this procedure build upon the procedure “Viewing and Adjusting the Compressed Mode Signal”
on page 537. There are two ways that you can set your carrier to noise ratio (C/N). One is by directly
entering your C/N value and the other is by setting the energy per bit to noise ratio (Eb/No) value. Setting
your Eb/No will change your C/N and the opposite is also true.
The following ESG tasks teach you how to set the overall C/N ratio for the uplink W-CDMA signal and the
Eb/No value referenced to individual physical or transport channels.
Setting the Carrier to Noise Ratio
1. Press Mode Setup to return to the top-level real-time W-CDMA menu.
2. Press Link Control > PhyCH Setup > DPCH AWGN Setup > Channel State Off On to On.
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3. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new settings
are not be applied to the signal until this softkey is pressed. This softkey needs to be pressed whenever
you make parameter changes with the AWGN editor table.
4. Set the channel to noise ratio (C/N).
a. Move the cursor to highlight the C/N value field.
b. Press 25 > dB.
NOTE
C/N values less than 10 dB may not be visible on a spectrum analyzer.
You have now set the overall carrier to noise ratio to 25 dB and turned on noise. This is done to apply a
discernible level of noise across the entire channel spectrum. Figure 16-42 shows the signal on the PSA
display.
Figure 16-42
C/N Setting
W-CDMA Signal
Added Noise Level
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Setting EbNo
1. Configure the noise for a particular channel.
a. Move the cursor to highlight the Eb Ref field.
b. Press Edit Item > DPDCH > Apply Channel Setup.
2. Set the channel Eb/No value
a. Move the cursor to highlight the Eb/No value field.
b. Press 10 > dB.
NOTE
C/N values less than 10 dB may not be visible on a spectrum analyzer.
You have now set the Eb/No value for the DPDCH channel to 10 dB. Notice that modifying the Eb/No value
for a channel will change the overall carrier to noise ratio and the Eb/No value for all other active channels.
The 10 dB setting for Eb/No has decreased the C/N value to where the W-CDMA signal is almost hidden by
the noise. For reliable results when making hand calculations to determine or verify Eb/No values, it is
recommended that you first scale the code domain power to 0 dB to display the normalized relative channel
power levels (see “Scaling to 0 dB” on page 560).
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Figure 16-43
Eb/No Setting
W-CDMA Signal
Added Noise Level
Using the Transmit Power Control
The tasks in this procedure teach you how to set up dynamic DPCH power control using an external signal.
In this closed loop example, the ESG is used to communicate a UE response to TPC commands.
Connecting the ESG to a Base Transceiver Station
1. Connect the ESG to the base station as shown in Figure 16-44.
2. Configure the base station to send a TPC signal, and receive the RF signal.
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Figure 16-44
ESG to Base Station Connection Diagram
Configuring the RF Output
1. Preset the ESG.
2. Set the carrier frequency to 1.95 GHz.
3. Set the carrier power to −10 dBm.
4. Turn on the RF output.
Selecting a DPCH Channel
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Up.
2. Press Link Control > PhyCH Type > DPCH > Return.
Generating the Baseband Signal
Press W-CDMA Off On to On.
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Configuring an External Signal for DPCH Power Control
1. Press Link Control > Power Mode Norm TPC to TPC.
2. Press PhCH Setup > Transmit Power Control Setup.
This accesses a softkey menu and a table editor that enables you to set the power parameters.
Figure 16-45 on page 527 displays the transmit power control menu and data fields.
Figure 16-45
Transmit Power Control Setup Menu
Relative power
Absolute power in
relation to carrier power
3. Highlight the Min Power field and press Edit Item > −35 > dB.
NOTE
The Min Power and Init Power fields are linked to the Power Step field. The values
will automatically round to a lower value if the selected Power Step value requires such an
adjustment.
4. Highlight the Init Power field and press Edit Item > −20 > dB.
Notice that the absolute power values changed.
5. Highlight the Power Step field and press Edit Item > 2.0 dB.
Notice that the Min Power field value is rounded to a lower value (−35 dB to −34 dB).
6. Press Apply Channel Setup.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new
parameters will not be applied to the signal until this softkey is pressed.
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7. Start the power control.
Press Power Hold Off On to Off.
NOTE
The default for Power Hold automatically sets the power hold mode to On. In this mode the
transmission power remains constant. In addition, the ALC function is turned off and the
ALC OFF annunciator appears on the status bar.
Figure 16-46 on page 528 shows how the power control feature is implemented.
Figure 16-46
DPCH External Power Control
8. Stop the power control.
Press Power Hold Off On to On.
9. Return to initial power level.
Press Reset to Initial Power.
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Compressed Mode Single Transmission Gap Pattern Sequence (TGPS) Overview
Compressed Mode Single Transmission Gap Pattern Sequence (TGPS)
Overview
The compressed mode is very flexible with many adjustable parameters. You can have one or two
transmission gaps. When two gaps are used, each gap can have a different length and operate using the
single or double frame method. Table 16-3 describes some of the parameters that are available for the
compressed mode. The compressed mode frames are fully coded which enables you to perform BER and
BLER testing of the receiver.
The ESG also supports multiple transmission gap pattern sequences (one to six). This enables you to set up
multiple pattern sequences. For more information, see “Compressed Mode Multiple Transmission Gap
Pattern Sequence (TGPS) Overview” on page 540.
Table 16-3
Uplink Compressed Mode Parameters
Name
Definition
Transmission gap pattern repetition count (TGPRC)
Number of transmission gap patterns within the
transmission gap pattern sequence.
Transmission gap connection frame number (TGCFN) CFN of the first compressed frame of the first
pattern within the transmission gap pattern
sequence.
Transmission gap slot number
(TGSN)
Slot number of the first transmission gap within
the first radio frame of the transmission gap
pattern.
Transmission gap length 1
(TGL1)
Duration of the first transmission gap within the
transmission gap pattern.
Transmission gap length 2
(TGL2)
Duration of the second transmission gap.
Transmission gap duration
(TGD)
This is the distance, measured in slots, from the
beginning of the first transmission gap to the
beginning of the second transmission gap.
Transmission gap pattern length 1
(TGPL1)
Duration of first transmission gap pattern that
includes TGL1/2.
Transmission gap pattern length 2
(TGPL2)
Duration of the second transmission gap pattern
that includes TGL1/2.
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Table 16-3
Uplink Compressed Mode Parameters (Continued)
Name
Definition
Stop connection frame number
(Stop CFN)
CFN of the last radio frame.
Transmission gap pattern sequence identifier (TGPSI) This identifies the currently selected transmission
gap pattern sequence.
Transmission gap pattern sequence
(TGPS)
530
This lets you select whether or not to transmit the
current TGPSI. Active it will be transmitted,
inactive it will not be transmitted.
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Setting Up Compressed Mode for a Single TGPS Transmission
Setting Up Compressed Mode for a Single TGPS Transmission
Using the compressed mode can turn off the ALC feature. For reliable results, you may need to perform a
power search. Before completing this procedure, refer to “Special Power Control Considerations When
Using DPCCH/DPDCH in Compressed Mode or PRACH” on page 582.
Equipment Setup
Connect the ESG to the Agilent E4440A PSA Spectrum Analyzer or an equivalent instrument as shown in
Figure 16-47.
Figure 16-47
PSA Setup
Configuring the RF Output
1. Press the Preset hardkey.
2. Set the frequency and amplitude values.
3. Press the RF On/Off hardkey to On.
Steps two and three can be performed either before or after setting the W-CDMA signal parameters.
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Setting Up Compressed Mode for a Single TGPS Transmission
Accessing the W-CDMA Modulation Format and Selecting Uplink
Unless stated otherwise, all procedures or tasks begin from the first-level W-CDMA softkey menu accessed
in this procedure.
1. Press Mode > W-CDMA > Real Time W-CDMA.
This accesses the first-level W-CDMA softkey menu. From this display you can elect to set up the base
station parameters (downlink) or the user equipment (UE—uplink).
2. Using the Link Down Up softkey, ensure that Up is highlighted as shown in Figure 16-48.
Figure 16-48
First-Level W-CDMA Softkey Menu
Ensure that Up
is Highlighted
Setting UP the W-CDMA Signal Parameters
This procedure uses a reference measurement channel as the DPCH setup. All other DPCH parameters use
the factory preset values.
1. Press the Link Control softkey.
2. Ensure that DPCH is showing as the selected channel type for the PhyCH Type softkey. If not, press
PhyCH Type > DPCH.
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Figure 16-49
DPCH is Selected
Ensure that DPCH
is Showing
3. Press Ref Measure Setup > 64 kbps.
This configures the DPCH with a 64 kbps reference measurement channel according to the 3GPP
specifications. This reference measurement channel sets up two transport channels (DCH) and the
required DPCH parameters.
4. Press the Mode Setup hardkey to return to the first-level W-CDMA softkey menu.
Generating the Baseband Signal
Press the W-CDMA Off On softkey to On.
This step can be performed at anytime during the setup. The advantage of turning the format on before
setting up the signal, if you have a spectrum analyzer or some other measuring equipment connected, is you
can see the changes as they are made. However you may experience a slight delay in signal processing while
the ESG updates the W-CDMA signal with any changes that are made.
Configuring Compressed Mode
This task teaches you how to set up compressed frames.
1. Press Link Control > DPCH Rear Panel Setup > DPCH Output Signal Setup > More (1 of 2) > Compressed Frame
(RPS8).
This enables an output trigger signal at the rear panel EVENT 1 connector when the compressed frame is
transmitted.
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2. Press Return > Return > PhyCH Setup > Compressed Mode Setup.
This accesses the compressed mode TGPSI display and is shown in Figure 16-50. From this display, you
can select a TGPS using the TGPSI softkey, view its parameters, enter the table editor to make parameter
changes, and enable or disable the compressed mode feature. In this procedure, TGPSI 1 is used, which
is the factory preset cursor location. The factory preset selection for the Compressed Mode Off On softkey is
On.
Figure 16-50
TGPSI Display
Access selected TGPS
Table Editor
Enable/Disable
Compressed Mode
Ensure On is Highlighted
3. Press the Comp Parameter Setup softkey shown in Figure 16-50.
This accesses the table editor for the selected TGPS. The table editor, shown in Figure 16-51, is for
setting the parameters for the selected TGPSI number, which is TGPSI 1 for this procedure. To access
the previous display, press the Return hardkey.
Notice that the Comp Parameter Setup softkey is replaced with the Ref Param Setup softkey.
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Figure 16-51
Compressed Frame Parameters
Softkey Name Changes
4. Set slot eight of the frame as the starting slot for the first transmission gap.
a. Move the cursor to highlight the TGSN field.
b. Press 8 > Enter.
This sets the first compressed frame so it has eight slots (0–7) of data prior to the transmission gap that
starts with slot eight.
5. Set the first transmission gap length, which is expressed as a number of slots.
a. Move the cursor to highlight the TGL1 field.
b. Press 14 > Enter.
Out of the 15 slots per frame, the standard specifies that seven of them can be used as discontinuous
transmission (DTX) slots. However the total gap length can be spread over two frames. The value 14
denotes 14 DTX slots, which spans 2 frames. This is called the double-frame method. If the value was
seven or less, this would mean that the DTX slots are contained in one frame.
6. Set the second transmission gap length, which is expressed as a number of slots.
a. Move the cursor to highlight the TGL2 field.
b. Press 3 > Enter.
For the second transmission gap, the single frame method is used.
7. Set the spacing between the first and second transmission gaps, which is expressed as a number of slots.
a. Move the cursor to highlight the TGD field.
b. Press 37 > Enter.
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8. Set the duration of the first transmission gap pattern, which is expressed as a number of frames.
a. Move the cursor to highlight the TGPL1 field.
b. Press 6 > Enter.
9. Set the duration of the second transmission gap pattern, which is expressed as a number of frames.
a. Move the cursor to highlight the TGPL2 field.
b. Press 4 > Enter.
10. Set the compressed frame power relative to the non-compressed (normal) frames.
a. Move the cursor to highlight the PwrOffs field.
b. Press 6 > dB.
This enables you to compensate for reduced spreading gain. The higher power level makes the
compressed frames easier to view.
11. Enable the compressed frames.
Press the TGPS Inactive Active softkey until Active is highlighted.
12. Press the Apply Channel Setup softkey.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new settings
are not applied to the signal until this softkey is pressed.
Pressing this key disables the compressed mode trigger. Therefore whenever this key is pressed while
transmitting in compressed mode, the following step will have to be repeated.
13. Press the Compressed Mode Start Trigger softkey.
The Comp trg annunciator appears and the ESG is now transmitting compressed frames.
The ESG does not transmit compressed frames until an external start trigger is received or the Compressed
Mode Start Trigger softkey is pressed. Compressed frame transmission is terminated when an external stop
trigger is received, the Compressed Mode Stop Trigger softkey is pressed, or a parameter is changed and the
Apply Channel Setup softkey is pressed. You can also stop the transmitted compressed mode frames after a set
number of transmissions by changing the TGPRC field from Infinity to the desired number of repetitions.
Figure 16-52 shows what the ESG display looks like when this procedure is completed.
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Figure 16-52
Compressed Mode Setup
Viewing and Adjusting the Compressed Mode Signal
This procedure will show the ESG compressed signal output on the PSA display (Figure 16-53 on page 539)
using the parameters set in the previous procedures. In addition, you will learn how to set the compressed
mode transmission for a finite number of repetitions.
Configuring the E4440A PSA
1. Select the W-CDMA mode.
Press Mode > W-CDMA.
2. Select the mobile setup.
Press Mode Setup > Radio > Device BTS MS to MS.
3. Set the center frequency to the ESG carrier frequency. This procedure uses 1.95 GHz.
Press Frequency > 1.95 > GHz.
4. Select the time domain measurement.
Press Measure > More 1 of 2 > Waveform (Time Domain).
5. Set a Sweep time that lets you view the signal parameters.
Press Meas Setup > Sweep Time > 100 > ms.
6. Set the resolution bandwidth for a faster response time that captures the signal components.
Press Res BW > 1 > MHz.
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7. Trigger the spectrum analyzer from the rear panel input using the supplied ESG trigger signal.
Press Trig Source > Ext Rear.
8. Zoom in on the RF Envelope display
Press Zoom.
You can now see the compressed signal moving across the PSA display.
To remove any text showing on the display, press the ESC hardkey.
Adjusting the Number of Gap Patterns
This task builds upon the procedure “Configuring Compressed Mode” on page 533.
This task will set up the ESG so that the transmitted gap patterns have a finite repetition. This will enable
you to have a clearer view of how the compressed signal parameters affect the transmission.
1. Enter the number of transmitted gap patterns.
a. Highlight the TGPRC field.
b. Press 5 > Enter.
2. Press Apply Channel Setup > Compressed Mode Start Trigger.
The Comp Trg annunciator comes on and then goes off after 5 gap pattern transmissions. This indicates
that the compressed mode trigger is no longer active and the ESG has quit transmitting compressed
frames.
Notice that the frame pattern is now easily viewed on the PSA display and is shown in Figure 16-53. This
figure also points out some of the compressed mode parameters as they appear on the signal.
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Figure 16-53
Displayed Compressed Signal and Signal Parameters
TGSN
Slot 8
TGPL1—6 Frames
TGD—37 Slots
TGL1
14 DTX Slots
Spread Over
2 Frames
Chapter 16
TGPL2—4 Frames
PwrOffs—6 dB
TGL2
3 DTX Slots
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Compressed Mode Multiple Transmission Gap Pattern Sequence (TGPS) Overview
Compressed Mode Multiple Transmission Gap Pattern Sequence (TGPS)
Overview
Multiple TGPSs (pattern sequences) are used to sample frequencies from the various transmission formats
such as frequency division duplex (FDD), time division duplex (TDD), and GSM in preparation for a
handoff. The number of pattern sequences is dependent on the type(s) of transmission format you need to
sample. The following list shows the number of TGPSs that are required to receive each type of transmission
format:
FDD
one TGPS per FDD frequency
TDD
one TGPS per TDD signal
GSM
three TGPSs per GSM signal
For example, if you wanted to sample the frequencies for a FDD and GSM signal, you would need four
TGPSs, one for the FDD signal and three for the GSM signal. If you wanted to sample three FDD
frequencies, you would need three TGPSs.
The ESG supports up to six different pattern sequences. Setting up the compressed frame signal with
multiple TGPSs is very similar to setting up a compressed frame signal using a single TGPS that is
demonstrated in the section “Configuring Compressed Mode” on page 533.
Each TGPS has the same parameters that are described in Table 16-3 on page 529, and the parameters are
local to each pattern sequence, with the exception of the PowOffs field. This field is common (global) for
all TGSPs and sets the amount of power offset for the compressed frames relative to the normal frames.
When it is set in one TGPS, it is applied to all the active pattern sequences and is shown in the PowOffs
field.
Understanding Multiple TGPS Compressed Frame Alignment
When multiple TGPSs are used, it is very important to ensure that there are no overlapping compressed
frames configured for the same frame position. If compressed frame overlapping occurs, the ESG
discontinues the compressed frame transmission (compressed frame start trigger is terminated) and normal
frames are transmitted. When the compressed frames from a multiple TGPS signal are properly aligned, the
output is a composite signal that contains the compressed frames from all the pattern sequences. Both
conditions are demonstrated in Figure 16-54.
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Figure 16-54
Multiple TGPS Compressed Frame Alignment
Incorrect Compressed Frame Alignment
Correct Compressed Frame Alignment
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Compressed Mode Multiple Transmission Gap Pattern Sequence (TGPS) Overview
You can see in Figure 16-54 that an offset is required between the pattern sequences so the compressed
frames do not overlap. This is done using connection frame numbers (CFN), which are a subset of the
system frame numbers (SFN). Each value of the CFN indicates a frame number with the first frame
numbered zero. In Figure 16-54, TGPS 1 has a two frame offset since the first compressed frame starts at
frame two. This would require that TGPSI 1 has a CFN of two. TGPS 2 has no offset, so its CFN is zero. For
the compressed mode feature, the CFN is set using the TGCFN (transmission gap connection frame number)
field within the compressed mode display.
If you plan on a continuous signal output with multiple pattern sequences, you have to ensure that the
compressed frame alignment remains consistent. It is easy to set up a compressed frame sequence that
initially transmits the intended pattern, but as the signal progresses, the positioning for the compressed
frames among the multiple sequence patterns start overlapping. This problem is especially predominant
when multiple transmission gap lengths (TGL1/2) and transmission gap pattern lengths (TGPL1/2) are used.
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Setting Up Compressed Mode for a Multiple TGPS Transmission
Using the compressed mode can turn the ESG ALC feature off. For reliable results, you may need to
perform a power search. Before completing this procedure, refer to “Special Power Control Considerations
When Using DPCCH/DPDCH in Compressed Mode or PRACH” on page 582.
Prior to setting your multiple TGPS parameters, it is a good practice to diagram the compressed frame
output and transfer the diagram settings to the ESG. This can eliminate the trial and error method for
properly aligning the compressed frames among the pattern sequences.
Equipment Setup
Connect the ESG to the Agilent E4440A PSA Spectrum Analyzer or equivalent instrument as shown in
Figure 16-55.
Figure 16-55
PSA Setup
Configuring the RF Output
1. Press the Preset hardkey.
2. Set the frequency and amplitude values.
3. Press the RF On/Off hardkey to On.
Steps two and three can be performed either before or after setting the W-CDMA signal parameters.
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Accessing the W-CDMA Modulation Format and Selecting Uplink
Unless stated otherwise, all procedures and tasks begin from the first-level W-CDMA softkey menu
accessed in this procedure.
1. Press Mode > W-CDMA > Real Time W-CDMA.
This accesses the first-level W-CDMA softkey menu. From this display you can elect to set up the base
station parameters (downlink) or the user equipment (UE—uplink).
2. Using the Link Down Up softkey, ensure that Up is highlighted as shown in Figure 16-56.
Figure 16-56
First-Level W-CDMA Softkey Menu
Ensure that Up
is Highlighted
Setting UP the W-CDMA Signal Parameters
This procedure uses a reference measurement channel as the DPCH setup. All other DPCH parameters are
left at factory preset values.
1. Press the Link Control softkey.
2. Ensure that DPCH is showing as the selected channel type for the PhyCH Type softkey. If not, press
PhyCH Type > DPCH.
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Figure 16-57
DPCH is Selected
Ensure that DPCH
is Showing
3. Press Ref Measure Setup > 64 kbps.
This configures the DPCH with a 64 kbps reference measurement channel according to the 3GPP
specifications. This reference measurement channel sets up two transport channels (DCH) and the
required DPCH parameters.
Selecting the Rear Panel Output Trigger
This procedure builds upon the previous procedure “Setting UP the W-CDMA Signal Parameters” on
page 544.
1. Press DPCH Rear Panel Setup > DPCH Output Signal Setup > More (1 of 2) >
Compressed Frame (RPS8).
This enables an output trigger signal at the rear panel EVENT 1 connector when a compressed frame is
transmitted.
2. Press the Mode Setup softkey to return to the first-level W-CDMA softkey menu.
Generating the Baseband Signal
Press the W-CDMA Off On softkey to On.
This step can be performed at anytime during the setup. The advantage of turning the format on before
setting up the compressed frame signal, if you have a spectrum analyzer or some other measuring equipment
connected, is you can see the changes as they are applied to the signal. However you may experience a slight
delay in signal processing while the ESG updates the W-CDMA signal with any changes that are made. If
you want to configure a spectrum analyzer to view the ESG signal during the setup, see “Viewing the
Multiple TGPSI Signal” on page 552.
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Configuring TGPSI 1
1. Press Link Control > PhyCH Setup > Compressed Mode Setup.
This accesses the compressed mode TGPSI display and is shown in Figure 16-58. From this display, you
can select a TGPS using the TGPSI softkey, view its parameters, enter the table editor to make parameter
changes, and enable or disable the compressed mode feature. TGPSI 1 is the factory preset cursor
location and On is the factory preset selection for the Compressed Mode Off On softkey.
Figure 16-58
TGPSI Display
Access selected TGPS
Table Editor
Enable/Disable
Compressed Mode
Ensure On is Highlighted
2. Press the Comp Parameter Setup softkey shown in Figure 16-58.
This accesses the table editor for the selected TGPS. The table editor, shown in Figure 16-59, is for
setting the parameters for the selected TGPSI number, which is TGPSI 1 for this procedure. To access
the previous display, press the Return hardkey.
Notice that the Comp Parameter Setup softkey is replaced with the Ref Param Setup softkey.
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Figure 16-59
Compressed Frame Parameters
Softkey Name Changes
3. Set slot five of the frame as the starting slot for the first transmission gap.
a. Move the cursor to highlight the TGSN field.
b. Press 5 > Enter.
This sets the first compressed frame so it has five slots (0–4) of data prior to the transmission gap that
starts with slot five.
4. Set the first transmission gap length which is expressed as a number of slots.
a. Move the cursor to highlight the TGL1 field.
b. Press 5 > Enter.
Out of the 15 slots per frame, the standard specifies that seven of them can be used as discontinuous
transmission (DTX) slots. However the total gap length can be spread over two frames. The value 5
denotes 5 DTX slots. Since the TGSN value previously entered is also five, this would mean that the
single frame method is being used.
5. Set the second transmission gap length which is expressed as a number of slots.
a. Move the cursor to highlight the TGL2 field.
b. Press 7 > Enter.
For the second transmission gap, the single frame method is also used.
6. Set the spacing between the first and second transmission gaps expressed as a number of slots.
a. Move the cursor to highlight the TGD field.
b. Press 30 > Enter.
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7. Set the duration of the first transmission gap pattern which is expressed as a number of frames.
a. Move the cursor to highlight the TGPL1 field.
b. Press 5 > Enter.
If desired, you can also establish a second gap pattern using the TGPL2 field, however this does create a
more complex signal that can make it harder to keep compressed frames in proper alignment among the
multiple pattern sequences.
8. Set the compressed frame power relative to the non-compressed frames.
a. Move the cursor to highlight the PwrOffs field.
b. Press 6 > dB.
This is a global setting for all TGPSIs. It enables you to compensate for reduced spreading gain. The
higher power level makes the compressed frames easier to view.
9. Press the TGPS Inactive Active softkey until Active is highlighted.
This enables TGPSI 1 and can be pressed either in the current display or in the previous TGPSI display.
You have now completed configuring TGPSI 1. Figure 16-60 shows what the ESG display looks like
after completing this step.
Figure 16-60
Compressed Mode Setup for TGPSI 1
10. Press the Return hardkey to return to the TGPSI display.
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Configuring TGPSI 2
This procedure builds upon the previous procedure, “Configuring TGPSI 1” on page 546 and configures the
second TGPS so that the compressed frames from TGPSI 1 and 2 are properly positioned.
1. Press 2 > Enter > Comp Parameter Setup.
2. Set slot three of the frame as the starting slot for the first transmission gap.
a. Move the cursor to highlight the TGSN field.
b. Press 3 > Enter.
This sets the compressed frame so it has three slots (0–2) of data prior to the transmission gap that starts
with slot three.
3. Set the first transmission gap length which is expressed as a number of slots.
a. Move the cursor to highlight the TGL1 field.
b. Press 7 > Enter.
Out of the 15 slots per frame, the standard specifies that seven of them can be used as discontinuous
transmission (DTX) slots. However the total gap length can be spread over two frames. The value 7
denotes 7 DTX slots, which are contained in one frame since the TGSN value is three. So the single
frame method is being used.
4. Set the second transmission gap length which is expressed as a number of slots.
a. Move the cursor to highlight the TGL2 field.
b. Press 3 > Enter.
The single frame method is also used for the second transmission gap.
5. Set the spacing between the first and second transmission gaps expressed as a number of slots.
a. Move the cursor to highlight the TGD field.
b. Press 29 > Enter.
This positions the second transmission gap (TGL2 field) for TGPSI 2 so it occurs in the second
normal frame transmitted by TGPSI 1. If compressed frames from the different TGPSs occupy the
same frame position (overlap), the ESG will transmit only normal frames. This is shown in Figure
16-54 on page 541.
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6. Set the frame offset for the first compressed frame so it does not overlap a compressed frame from
TGPSI 1.
a. Move the cursor to highlight the TGCFN field.
b. Press 1 > Enter.
The connection frame numbers (CFN) are a subset of the system frame numbers (SFN). Each value
denotes the start of a new frame with zero being the first frame position. To avoid compressed frame
overlapping, you must position the compressed frames for TGPSI 2 so they occur during normal
frame transmissions for TGPSI 1. Since TGPSI 1 starts at TGCFN 0 (frame position one) and has a
normal frame in the second frame position, TGPSI 2 will start its first compressed frame in the
second frame position (CFN one).
7. Set the duration for the transmission gap pattern, which is expressed as a number of frames.
a. Move the cursor to highlight the TGPL1 field.
b. Press 5 > Enter.
This value is the same as for TGPSI 1. This ensures that my frame alignment is consistent over time
and keeps frame overlapping from occurring between the two pattern sequences for the current setup.
This setting alone does not keep the proper alignment consistent, it is the combination of this setting
and the other spacing values that ensure proper compressed frame alignment.
8. Press the TGPS Inactive Active softkey until Active is highlighted.
9. Press the Apply Channel Setup softkey.
When the Apply Needed annunciator appears, press the Apply Channel Setup softkey. The new settings
are not applied to the signal until this softkey is pressed.
Pressing this key disables the compressed mode trigger. Therefore, whenever this key is pressed while
transmitting in compressed mode, the compressed mode start trigger will have to be reapplied.
Figure 16-62 shows what the ESG display looks like when this step is completed.
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Figure 16-61
TGPSI 2 Setup
10. Press the Return hardkey to return to the TGPSI display.
11. Press the Compressed Mode Start Trigger softkey.
The Comp trg annunciator appears and the ESG is now transmitting compressed frames.
The ESG does not transmit compressed frames until an external start trigger is received or the Compressed
Mode Start Trigger softkey is pressed. Compressed frame transmission is terminated when an external stop
trigger is received, the Compressed Mode Stop Trigger softkey is pressed, or a parameter is changed and the
Apply Channel Setup softkey is pressed. You can also stop the transmitted compressed frames after a set
number of transmissions by changing the TGPRC field from Infinity to the desired number of repetitions.
Figure 16-62 shows what the ESG display looks like when this procedure is completed.
Figure 16-62
Chapter 16
Completed TGPSI Display
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Viewing the Multiple TGPSI Signal
1. Select the Spectrum Analysis mode.
Press Mode > Spectrum Analysis.
The W-CDMA mode can also be used, and is demonstrated in the task “Configuring the E4440A PSA”
on page 537.
2. Set the center frequency to match the ESG carrier signal. This procedure uses 1.95 GHz.
Press Frequency > 1.95 > GHz.
3. Set the spectrum analyzer for a zero span (time domain measurement).
Press Span > Zero Span.
4. Set the resolution bandwidth for a faster response time that captures the signal components.
Press BW/Avg > Res BW > 8 > MHz.
5. Set a Sweep time that lets you view the signal parameters.
Press Sweep > Sweep Time > 100 > ms.
This setting makes it easier to view the frames since each vertical graticle is 10 ms, which is the same
time period for one frame.
6. Trigger the spectrum analyzer from the rear panel input using the supplied ESG trigger signal.
Press Trig > Ext Rear.
Figure 16-63 shows the ESG output signal configured in the previous section, “Setting Up Compressed
Mode for a Multiple TGPS Transmission” on page 543. In the figure, you can see two transmissions for
TGPSI 1 and one full and a partial transmission for TGPSI 2. Notice the one frame offset for the start of
TGPSI 2 that was created by setting its TGCFN field to one.
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Figure 16-63
Multiple TGPSIs on the Spectrum Analyzer Display
TGPSI 1—5 Frames
TGPSI 2—5 Frames
TGPSI 1
TGCFN 0
PwrOffs—6 dB
TGPSI 2
TGCFN 1
TGPSI 1
TGL1—5 Slots
TGPSI 2
TGL1—7 Slots
Chapter 16
TGPSI 1
TGL2—7 Slots
TGPSI 2
TGL2—3 Slots
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Configuring the UE Setup
Configuring the UE Setup
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Up.
2. Press UE Setup.
This opens a menu where you can select the filtering type and adjust the chip rate for the simulated user
equipment (see Figure 16-64). Use the arrow keys or the knob to highlight the data fields for editing.
Press Edit Item to change the value for the desired user equipment parameter.
Figure 16-64
User Equipment Setup
Press to Access the
UE Parameters
Press to Edit the Selected
UE Parameter
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Locating Rear Panel Input Signal Connectors
Locating Rear Panel Input Signal Connectors
One feature of the W-CDMA uplink format is the ease in which you can locate a rear panel input connector
for a particular signal application. This feature applies to both the DPCH and the PRACH. This procedure
guides you through the softkey menus to where you can view the information.
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Up.
2. Press Link Control > PhyCH Type.
The PhyCH Type softkey opens another menu where you can select either the PRACH or DPCH mode.
The factory default is DPCH. You need to select the mode for which the input signal is intended. If the
input signal is the AICH for the PRACH, you would need to be in the PRACH mode to see which
connector accepts the AICH signal.
3. Select the channel mode, DPCH or PRACH.
Once a mode is selected, you will be returned to the previous softkey menu.
4. Press DPCH Rear Panel Setup or PRACH Rear Panel Setup depending on the selected mode.
5. Press DPCH Input Signal Setup or PRACH Input Signal Setup depending on the selected mode.
The information shown in the text area, displays the connector and the type of input signal it accepts. For
example, the BBG Reference in listing (BASEBAND GEN REF IN connector) in the Rear Panel
Ports column accepts a baseband generator (BBG) chip clock signal. Figure 16-65 shows the position
of this information on the DPCH signal input display.
Figure 16-65
Rear Panel Connector Information
BBG Reference in
Signal Type
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6. To exit this display, press either Mode Setup to return to the top-level W-CDMA softkey menu or press
Return until you come to the desired softkey menu/display.
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Configuring Rear Panel Output Signals
The W-CDMA uplink format provides you the ability to configure output signals for the various rear panel
output connectors. This lets you select trigger signals based on your needs and applies to both the DPCH and
the PRACH. This procedure guides you through the softkey menus to where you can configure your signals.
Accessing the Output Trigger Signal Menu
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Up.
2. Press Link Control > PhyCH Type.
The PhyCH Type softkey opens another menu where you can select either the PRACH or DPCH mode.
The factory default is DPCH. You need to select the mode for which the input signal is intended. If the
desired output signal is the PRACH pulse, you would need to be in the PRACH mode to select the signal
and an output connector.
3. Select the channel mode, DPCH or PRACH.
Once a mode is selected, you will be returned to the previous softkey menu.
4. Press DPCH Rear Panel Setup or PRACH Rear Panel Setup depending on the selected mode.
5. Press DPCH Output Signal Setup or PRACH Output Signal Setup depending on the selected mode.
Selecting an Output Signal
This procedure will use a PRACH output signal selection as an example. While the signal selection may
change between the PRACH and DPCH modes, the process remains the same.
1. Using the arrow keys, highlight the item in the Signal column that corresponds to the Event2
connector listed under the Rear Panel Ports column.
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Figure 16-66
Output Connector Selection
Event2 Connector
Selection
Highlighted
Item
2. Press More (1 of 3) > More (2 of 3) > Preamble Pulse (RPS21).
Notice that under the Signal column in row two of the text display, NONE(RPSO) changed to
Preamble pulse(RPS21). This corresponds to the Event2 connector listed under the Rear Panel
ports column. Figure 16-67 shows what the ESG display looks like after the preamble pulse selection
is made.
Figure 16-67
Output Trigger Signal Selection
Preamble Pulse
Softkey
Preamble Pulse
Trigger Selected
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Configuring Rear Panel Output Signals
Deselecting an Output Signal
This procedure builds upon the previous procedure “Selecting an Output Signal”.
1. Press More (3 of 3).
This returns you to the top-level output signal selection display shown in Figure 16-66.
2. Highlight the Event2 connector listing.
3. Press NONE(RPSO).
Notice that the output signal selection listed in the Signal column has changed to None(RPSO). The
none indicates that there is no signal output selected for the corresponding connector.
Figure 16-68
Deselected Signal
NONE(RPSO)
Softkey
Now, No Trigger
is Selected
Chapter 16
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Adjusting Code Domain Power
Adjusting Code Domain Power
This procedure teaches you about scaling the uplink channels (DPDCH and DPCCH) to 0 dB on the ESG for
meeting the code domain power requirements.
Scaling to 0 dB
After changing the relative power level for a channel, the ESG automatically scales the total power to 0 dB,
while preserving the relative channel power levels. Although the displayed total power changes in value as
channel powers are adjusted, the actual total power is maintained at 0 dB. The displayed channel power
levels remain unchanged, reflecting only user-assigned values, so the user can complete the relative power
adjustments. This task teaches you how to update the display to show the normalized relative channel power
for each channel after completing your setup.
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Up.
2. Press Link Control > PhyCH Type > DPCH > PhyCH Setup > DPCH Power Setup >
Adjust Code Domain Power > Scale to 0 dB.
DPCH is the factory default channel mode.
The displayed power level for each channel is now changed to show the normalized relative channel power
and the displayed total power shows 0 dBm. Figure 16-69 is an example showing power levels before and
after the scale to 0 dB function.
Figure 16-69
Scaling to Zero dB (Uplink DPCCH/DPDCH)
Before Scaling to 0 dB
Displayed Power Levels
Displayed Total Power
After Scaling to 0 dB
Displayed Power Levels
Displayed Total Power
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Adjusting Code Domain Power
Setting Equal Channel Powers
This task teaches you how to set equal relative power levels for all active channels while maintaining the
code domain power of 0 dB. The normalized relative power level of each channel depends on the number of
active channels. This task is an alternative to scaling to
0 dB.
Press Adjust Code Domain Power > Equal Powers.
Both channels have now been set to equal powers. Figure 16-70 shows the displayed normalized relative
power levels after the Equal Powers softkey is pressed with two active channels. Depending on the entered
channel powers, the displayed total power may show a low residual value (such as 0.02 dB) due to decimal
rounding.
Figure 16-70
Equal Powers (Uplink DPCCH/DPDCH)
After Equal Powers
Displayed Power Levels
Chapter 16
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W-CDMA Uplink Concepts
Data Channel Air Interface Block Diagram
Reference Measurement Channels (RMC)
The W-CDMA real-time signal generation modulation format provides reference measurement channels
(RMC) at 12.2, 64, 144, and 384 kbps. This option also provides transport layer coding for AMR 12.2
(adaptive multi-rate) and UDI 64 (unrestricted digital information) protocols. Along with user defined
parameters for the DPCH, the ESG also supports the predefined 12.2 kbps RMC, 64 kbps RMC, 144 kbps
RMC, AMR 12.2 kbps, and UDI 64 kbps with compressed mode.
The signal generator provides one-button setup capabilities for transport channel configuration. The
dedicated physical channel DPDCH is predefined by pressing the Ref Measure Setup softkey (or sending the
appropriate SCPI commands) and selecting the desired RMC. RMC 12.2 kbps is the factory default
selection.
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Table 16-4 describes the uplink reference measurement channel (RMC) configurations.
Table 16-4
The Uplink RMC Predefined DPDCH Configuration
Parameter
DPCH Values at Specified Reference Measurement Channel
Channel Rate
12.2 kbps
64 kbps
144 kbps
384 kbps
UDI 64 kbps
AMR 12.2 kbps
Power
0.00 dB
0.00 dB
0.00 dB
0.00 dB
0.00 dB
0.00 dB
Beta
15
15
15
15
15
15
Data
TrCH
TrCH
TrCH
TrCH
TrCH
TrCH
Symbol Ratea
60 ksps
240 ksps
480 ksps
960 ksps
240 ksps
60 ksps
Slot Formata
2
4
5
6
4
2
Channel Code
16
4
2
1
4
16
a. The user-selectable symbol rate and slot format parameters are coupled together.
Transition between Normal Frame and Compressed Frame
In a dedicated physical channel (DPCH), an RF notch exists at the transition between a normal frame and a
compressed frame (see Figure 16-71). In a CW signal, the notch measures approximately five microseconds
in length and approximately seven decibels in depth (peak compressed mode to peak normal mode).
Figure 16-71
Chapter 16
RF Notch with Compressed Mode Transitions
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Settling Time during User Event for DPCH Compressed Mode
Some user events, such as changing the amplitude or frequency, will cause the signal to jump to an
unexpected amplitude for a short period of time before it settles to expected parameters. This transition
period is approximately 200 milliseconds (see Figure 16-72). It is, therefore, important to allow for this time
when you make changes to signal characteristics. If you make changes using remote SCPI commands, insert
wait instructions into the program. The following events can cause this unstable transition time:
•
•
•
•
•
amplitude and frequency changes
RF switched on and off
modulation switched on and off
ALC switched on and off
saving or recalling states
Figure 16-72
DPCH Compressed Mode Signal after a Change in Amplitude
Connecting the ESG to a W-CDMA Base Station
Figure 16-73 shows the connections and signals necessary for the ESG to simulate user equipment when it is
connected to a base station.
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Figure 16-73
Cable Connections
System Triggering and Synchronization
Either the system frame number reset signal or the frame clock which is applied to the PATT TRIG IN
connector can be set as a system trigger signal. After a delay time defined by the sum of 1024 chips (T0 =
the standard timing offset between downlink and uplink), timing offset, and timeslot offset (plus 10 ms when
the SFN reset signal is used), a sync signal is generated to time align all other signals. The RF output signal
is generated after the fixed delay of the processing time by the hardware. This delay applies to DPCH mode
only. Refer to “Synchronization Diagrams” on page 574 for more information.
For increased measurement accuracy, the signal generator’s rear panel 10 MHz OUT frequency reference
can be utilized by other instruments in the test system.
Connector Assignments for W-CDMA Uplink
This section describes connector assignments for the W-CDMA uplink personality. The block diagram in
Figure 16-74 shows these connector assignments. Notice the front panel connectors are not used in the
uplink real-time signal generation personality.
Chapter 16
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Figure 16-74
ESG I/O Connectors for W-CDMA Uplink
Refer to Table 16-5 for descriptions on connector assignments when using W-CDMA uplink in DPCH
mode. For PRACH mode, refer to Table 16-6 on page 568.
Table 16-5
Connector Descriptions for DPCH Mode
Connector Label
Connector Type
Input/Ou
tput
Assigned Signal
PATTERN
TRIGGER IN
BNC
Input
Frame sync trigger. This signal determines the
SFN frame timing of the ESG so it is
synchronous with the base station.
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Table 16-5
Connector Descriptions for DPCH Mode (Continued)
Connector Label
Connector Type
Input/Ou
tput
Assigned Signal
PATTERN
TRIGGER IN 2
AUX I/O Pin 17
Input
Compressed mode stop trigger. Compressed
mode must be active. The trigger instructs the
signal generator to stop the compressed mode
pattern at the frame number specified in the
Stop CFN# data field.
ALT POWER IN
AUX I/O Pin 16
Input
Trigger for user-defined TPC bits.
BURST GATE IN
BNC
Input
Compressed mode start trigger or the TPC
control signal.
The compressed mode or TPC mode must be
active. The compressed mode start trigger
instructs the signal generator to begin the
compressed mode pattern. The TPC control
signal instructs the ESG to increase or decrease
the DPCH signal power relative to the carrier
power.
BASEBAND
GEN REF IN
BNC
Input
External system clock in. This connector is used
for chip clock input when using external data
clock sources. To use an external signal source as
the data clock input, press BBG Chip Clock Ext Int
to Ext or send the appropriate SCPI command.
This clock rate can be multiplied by setting the
Ext Clock Rate X1 X2 X4 softkey to either x2 or x4.
10 MHz IN
BNC
Input
10 MHz reference in.
10 MHz OUT
BNC
Output
10 MHz reference out.
EVENT 1
BNC
Output
Signal assigned by user. Default is DPDCH raw
data.
EVENT 2
BNC
Output
Signal assigned by user. Default is DPDCH raw
data clock.
EVENT 3
AUX I/O Pin 19
Output
Signal assigned by user. Default is none.
EVENT 4
AUX I/O Pin 18
Output
Signal assigned by user. Default is none.
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Table 16-5
Connector Descriptions for DPCH Mode (Continued)
Connector Label
Connector Type
Input/Ou
tput
Assigned Signal
DATA OUT
AUX I/O Pin 7
Output
Signal assigned by user. Default is DPCCH raw
data.
DATA CLOCK
OUT
AUX I/O Pin 6
Output
Signal assigned by user. Default is chip clock.
SYMBOL SYNC
OUT
AUX I/O Pin 5
Output
Signal assigned by user. Default is sync trigger
reply.
Table 16-6
Connector Descriptions for PRACH Mode
Connector Label
Connector Type
Input/Ou
tput
Assigned Signal
PATTERN
TRIGGER IN
BNC
Input
Frame sync trigger. This signal determines the
SFN frame timing of the ESG so it is
synchronous with the base station.
PATTERN
TRIGGER IN 2
AUX I/O Pin 17
Input
AICH trigger input. This connector pin is used
for the AICH trigger when operating in PRACH
mode. The AICH trigger instructs the signal
generator to generate the message part. The
Message Part data field must be set to AICH.
ALT POWER IN
AUX I/O Pin 16
Input
Unused.
BURST GATE IN
BNC
Input
PRACH start trigger. The connector is used for
the PRACH start trigger when PRACH is
selected in the physical channel setup. The
PRACH start trigger instructs the signal
generator to begin the PRACH pattern.
BASEBAND
GEN REF IN
BNC
Input
External system clock in. This connector is used
for chip clock input when using external data
clock sources. To use an external signal source as
the data clock input, press BBG Chip Clock Ext Int
to Ext or send the appropriate SCPI command.
This clock rate can be multiplied by setting the
Ext Clock Rate X1 X2 X4 softkey to either x2 or x4.
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Table 16-6
Connector Descriptions for PRACH Mode (Continued)
Connector Label
Connector Type
Input/Ou
tput
Assigned Signal
10 MHz IN
BNC
Input
10 MHz reference in.
10 MHz OUT
BNC
Output
10 MHz reference out.
EVENT 1
BNC
Output
Signal assigned by user. Default is none.
EVENT 2
BNC
Output
Signal assigned by user. Default is none.
EVENT 3
AUX I/O Pin 19
Output
Signal assigned by user. Default is none.
EVENT 4
AUX I/O Pin 18
Output
Signal assigned by user. Default is none.
DATA OUT
AUX I/O Pin 7
Output
Signal assigned by user. Default is none.
DATA CLOCK
OUT
AUX I/O Pin 6
Output
Signal assigned by user. Default is none.
SYMBOL SYNC
OUT
AUX I/O Pin 5
Output
Signal assigned by user. Default is none.
Signal Descriptions for W-CDMA Uplink
Figure 16-75 shows how W-CDMA uplink input and output signals align with respect to time. Notice that all
signals are aligned with the leading edge of the chip clock pulse.
Chapter 16
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Figure 16-75
Input/Output Signal Alignment
DPCH Mode
Table 16-7 provides descriptions for fixed and user-selectable signals available in DPCH mode. Figure
16-76 on page 571 shows an example of DPCH output timing alignment.
Table 16-7
Signal Descriptions for DPCH Mode
Signal Label
Input/
Output
Signal Description
SCPI
Syntax
Frame Sync Trigger
Input
The input signal can be set to either the frame clock
or the system frame number SFN) reset signal by
toggling the Sync Source FClk SFN softkey. The frame
clock can be set to 10, 20, 40, 80, or 2560 ms.
FSYN
TPC User File Trigger
Input
Trigger for user-defined TPC bits.
USER
Compressed Mode Start
Trigger
Input
Trigger to start compressed mode.
CSTT
Compressed Mode Stop
Trigger
Input
Trigger to stop compressed mode.
CSPT
None
Output
No signal.
RPS0
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Table 16-7
Signal Descriptions for DPCH Mode (Continued)
Signal Label
Input/
Output
Signal Description
SCPI
Syntax
Chip Clock
Output
Chip clock. 3.84 MHz is the default setting.
RPS1
Trigger Sync Reply
(system sync output)
Output
Response pulse of the frame sync trigger. The frame
sync trigger reply reports that the frame sync trigger
was received, and is used to adjust frame timing.
When the system trigger is not received, the system
sync output pulse is not generated.
RPS7
DPDCH Raw Data
Output
DPDCH data after 2nd interleaver (before spreading
and scrambling).
RPS2
DPCCH Raw Data
Output
DPCCH data after 2nd interleaver (before spreading
and scrambling).
RPS4
DPDCH Raw Data
Clock
Output
The clock for DPDCH raw data. The rate depends on
the slot format (data rate) of DPDCH.
RPS3
DPCCH Raw Data
Clock
Output
The clock for DPCCH raw data. The rate of this
clock is fixed at 15 kHz.
RPS5
10 ms Frame Pulse
Output
Indicates the frame boundaries for data generation.
RPS6
TTI Frame Pulse
Output
Indicates the frame boundaries for TTI.
RPS9
CFN #0 Frame Pulse
Output
Indicates the frame boundaries for CFN frame #0.
RPS10
Compressed Frame
Output
This signal indicates the status of the compressed
frame. A 0 indicates a normal frame. A 1 indicates a
compressed frame.
RPS8
Figure 16-76
Chapter 16
DPCH Signal Alignment
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PRACH Mode
Table 16-8 provides descriptions for fixed and user-selectable signals available in PRACH mode. Figure
16-77 on page 573 shows an example of PRACH output timing alignment.
Table 16-8
Signal Descriptions for PRACH Mode
Signal Label
Input/
Output
Signal Description
SCPI
Syntax
Frame Sync Trigger
Input
The input signal can be set to either the frame clock
or the system frame number SFN) reset signal by
toggling the Sync Source FClk SFN softkey. The frame
clock can be set to 10, 20, 40, 80, or 2560 ms.
FSYN
PRACH Start Trigger
Input
Trigger to start PRACH.
PSTR
AICH Trigger
Input
Trigger to start AICH.
AITR
None
Output
No signal.
RPS0
Chip Clock
Output
Chip clock. 3.84 MHz is the default setting.
RPS1
Trigger Sync Reply
(system sync output)
Output
Response pulse of the frame sync trigger. The frame
sync trigger reply indicates how much frame
alignment was necessary.
RPS7
Preamble Raw Data
Output
Preamble data after 2nd interleaver (before
spreading and scrambling).
RPS15
Preamble Raw Data
Clock
Output
The clock for preamble raw data.
RPS16
Message Data Raw
Data
Output
The data for the message data part after 2nd
interleaver (before spreading and scrambling).
RPS11
Message Ctrl Raw Data
Output
The data for the message control part after 2nd
interleaver (before spreading and scrambling).
RPS13
Message Data Raw
Data Clock
Output
The clock for the message data part raw data.
RPS12
Message Ctrl Raw Data
Clock
Output
The clock for the message control part raw data.
RPS14
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Table 16-8
Signal Descriptions for PRACH Mode (Continued)
Signal Label
Input/
Output
Signal Description
SCPI
Syntax
PRACH Processing
Output
This signal indicates the status of PRACH signaling.
The signal is high until the configured number of
PRACH repetitions is complete. A 0 indicates the
PRACH signal is off. A 1 indicates the PRACH
signal is generating. The signal’s state changes in
accordance with access slot resolution.
RPS19
Sub-Channel Timing
Output
Indicates sub-channel timing, which is specified
through the user interface. A PRACH data stream
must begin on the leading edge of one of these
pulses.
RPS17
10 ms Frame Pulse
Output
Indicates the frame boundaries for SFN.
RPS6
80 ms Frame Pulse
Output
Indicates the frame boundaries for SFN
mod 8 = 0.
RPS20
Preamble Pulse
Output
Indicates the start for each preamble access slot.
RPS21
Message Pulse
Output
Indicates the start of an access slot when the message
part is going to be transmitted.
RPS22
PRACH Pulse
Output
Indicates the beginning access slot boundary of a
PRACH repetition (preamble only or
preamble+message).
RPS23
Figure 16-77
Chapter 16
PRACH Signal Alignment
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Synchronization Diagrams
Signal Alignment for Default DPCH Mode
Figure 16-78 illustrates the timing relationships between the signals from the rear panel BNC input and
output connectors relative to the RF Output connector for default signal assignments in DPCH mode. Signal
states are referenced to the chip clock provided at the DATA CLK OUT connector.
Figure 16-78
Signal Alignment for Default DPCH Mode
DPCH Synchronization
Figure 16-79 illustrates the timing alignment for the DPCH channel. Delay time is defined by the sum of T0
(1024 chips = the standard timing offset between downlink and uplink), timing offset, and timeslot offset.
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Figure 16-79
DPCH Synchronization - Frame Timing Alignment
Figure 16-80 illustrates the frame number alignment for the DPCH channel. The frame number is aligned by
the frame sync trigger signal from the BTS. When using the frame clock, set the frame clock period to be
equal or greater than the longest transport channel TTI period (select 10, 20, 40, or 80 ms). In Figure 16-80,
Reference Measurement Channel 12.2k requires a frame clock of 20 ms or longer to achieve the correct
frame number alignment. Using a frame clock of 10 ms would cause an unpredictable frame timing
alignment with the transport channel TTI period. Best results are achieved when the frame clock is set to 80
or 2560 ms, or a system frame number reset signal is used. (The signal generator’s TTI period can be
measured on the TTI frame pulse from the rear panel.)
Figure 16-80
Chapter 16
DPCH Synchronization - Frame Number Alignment
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Figure 16-81 illustrates the frame number alignment for compressed mode when the TGPRC data field is set
to Infinity. In this case, the frame clock period must be equal to or be a multiple of the compressed mode
(TG pattern length) definition.
Figure 16-81
576
DPCH Synchronization - Frame Number Alignment for Continuous (Infinity)
Compressed Mode
Chapter 16
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W-CDMA Uplink Concepts
Figure 16-82 illustrates the frame number alignment for compressed mode when it is required to align with
CFN number counting. This mode of operation requires a frame clock of 2560 ms or a system frame number
reset signal as the frame sync trigger.
Figure 16-82
Chapter 16
DPCH Synchronization - Frame Number Alignment for Compressed Mode with CFN
Number Count
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W-CDMA Uplink Concepts
PRACH Synchronization
Figure 16-83 illustrates the frame timing alignment for the PRACH channel. Delay time is defined by the
sum of the timing offset and timeslot offset minus the Tp-a value.
Figure 16-83
PRACH Synchronization - Frame Timing Alignment
Figure 16-84 illustrates the frame number alignment for the PRACH channel. The frame number is aligned
by the frame sync trigger signal from the BTS. Best results are achieved when the frame clock is set to 80 or
2560 ms, or a system frame number reset signal is used. When the sync trigger is a frame clock of 10, 20, or
40 ms, the signal generator can align frame timing. However, an 80 ms period must equal the cycle of
sub-channel 0 and frame boundary to achieve frame number alignment. (The signal generator’s frame
number alignment can be observed on the 80 ms frame pulse from the rear panel.)
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Figure 16-84
PRACH Synchronization - Frame Number Alignment
Frame Sync Trigger Status Indicator
The signal generator uses a synchronization annunciator to indicate the state of the signal generator’s frame
synchronization and whether or not a synchronization trigger was received. Figure 16-85 shows the uplink
user interface (UI) and the synchronization annunciator. When Sync Trg replaces Out Sync as the current
annunciator, the frame sync trigger has either been received (dark text) or has not been received (gray text).
The conditions are described as follows:
Sync Trg (grayed out):
The frame sync trigger was not received after a trigger status reset.
Sync Trg (active):
The frame sync trigger was received after the trigger status is reset.
Out Sync:
Chapter 16
When the synchronization annunciator indicates Out Sync, the signal generator is not
synchronizing with the external frame sync trigger. It is only displayed when an
out-of-sync condition occurs. This indicator remains active until the next frame sync
trigger is received.
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Figure 16-85
Front Panel Display
Synchronization Annunciator
NOTE
The trigger status reset is automatically performed whenever the frame sync trigger mode is
changed or the Apply Channel Setup softkey activated.
Out Sync Annunciator
When the timing of the external frame synchronization signal does not match the signal generator’s frame
generation, the Out Sync annunciator is displayed. Out Sync replaces Sync Trg under these
conditions.
The signal generator’s frame synchronization method depends on the trigger mode selected:
Single Trigger
Continuous
Trigger
The frame timing is adjusted at the first trigger. All triggers, except the first one are
ignored and not used for signal generator frame timing.
All external triggers are used to adjust the signal generator’s frame timing.
Figure 16-86 describes trigger mode and synchronization patterns.
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Figure 16-86
Trigger Mode and Synchronization
The signal generator checks the timing difference between the external trigger and the internal frame timing
whenever an external trigger is received. If the single trigger mode is selected, the signal generator checks
the timing difference between the external trigger and the internal frame timing when the first trigger is
received. If continuous trigger mode is selected, timing is checked at each trigger signal. If there is a timing
difference in either mode, then the Out Sync annunciator is displayed.
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The signal generator’s behavior, when Out Sync is displayed, depends on the trigger mode used. Table
16-9 describes the signal generator’s behavior for different trigger modes.
Table 16-9
Trigger Mode
ESG output signal status on Out Sync.
Single
The ESG outputs frames even if Out Sync is displayed.
Continuous
The ESG output is discontinued. The synchronization is corrupt and no output is
available when Out Sync is displayed. The ESG timing is retriggered by the
external trigger when this occurs.
Special Power Control Considerations When Using DPCCH/DPDCH in Compressed Mode
or PRACH
When using either DPCCH/DPDCH in compressed mode or PRACH, more than a single power level is
required. In addition to the rapidly varying power levels for these two channels, there are also periods of
discontinuous transmission (gaps where no RF is transmitted). Under these conditions, the automatic level
control (ALC) will try to counteract the rapid power variations. To prevent this, the signal generator employs
ALC hold mode. However, even with ALC hold active, if the RF gap is longer than five seconds, the output
level may drift significantly. Under certain conditions, such as waiting for an input trigger, the length of the
RF gap is unpredictable. Under these conditions, the signal generator turns the ALC off. Table 16-10 on
page 582 shows the specific settings of the DPCCH/DPDCH in compressed mode or PRACH that will turn
the ALC off. Notice that the settings may differ for the mechanical attenuator.
Table 16-10
Conditions that Turn the ALC Off
Channel Type
Electronic Attenuator
Mechanical Attenuator
(Option UNB)
PRACH Settings
PRACH Trigger Source Immedi
Trigger softkey set to Trigger
PRACH Trigger Source Immedi
Trigger softkey set to Trigger
Message Part data field set
to AICH
or
or
Message Part data field set
to AICH
PRACH Mode Single Multi
or
softkey is set to Multi
PRACH Mode Single Multi
softkey is set to Multi
DPCCH/DPDCH Settings
582
not applicable
all compressed frames
(no normal frames)
Chapter 16
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W-CDMA Uplink Concepts
When one of the conditions listed in Table 16-10 turns the ALC off, a manual power search must be
performed in order to ensure the correct output power level. Pressing the Apply Channel Setup softkey
executes the manual power search function. Temperature changes or changes to certain signal generator
settings may cause the output power level to change over time. Even though the Apply Needed
annunciator may be off, it is recommended that you press Apply Channel Setup to perform a manual power
search at least every hour to maintain the correct output power level.
W-CDMA AWGN Measurements and Bandwidths
The AWGN (additive white Gaussian noise) feature produces a noise signal across a
7.68 MHz bandwidth (2x the W-CDMA 3.84 MHz bandwidth) and lets you enter values that adjust the noise
level across this spectrum. To resolve the noise signal’s effect on the W-CDMA signal, the ESG also
displays noise values across the W-CDMA 3.84 MHz bandwidth. In addition, the DPCH AWGN feature
shows the bandwidth of the noise signal during the period when it has a flat frequency response. This is
called the flat-noise bandwidth. Figure 16-87 shows the different noise settings/values as they appear on the
W-CDMA AWGN display along with a graphical representation of the noise signal showing the different
bandwidth features.
Chapter 16
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Figure 16-87
Noise Measurement Bandwidths
AWGN 7.68 MHz Entries
DPCH 3.84 MHz Values
Flat Noise Bandwidth
AWGN 7.68 MHz Entries
PRACH 3.84 MHz Values
As shown in Figure 16-87, the noise signal is added to the W-CDMA signal across the entire W-CDMA
signal spectrum. The ESG gives you two ways to control the noise level. You can adjust the noise using
either Eb/No (energy per bit to noise power density ratio) or C/N (carrier power to noise power ratio). Any
adjustment to either noise parameter, Eb/No or C/N, will affect the other; they are not mutually exclusive.
Eb/No lets you set the noise ratio relative to the power of the data stream for the selected reference channel,
versus setting the noise relative to the carrier power (C/N). For example, if you have the RACH transport
channel selected as the data source (Eb Ref field, see Figure 16-88) with a 12.2 kbps data rate, the
bandwidth for the data is 12.2 kHz. The data within this bandwidth has a certain power level. This power
level is what is used in the ratio for Eb/No.
When you use Eb/No, you can select the reference to use as the data power source. For example, you can use
any of the transport channels for the DPDCH, the PRACH transport channel, the PRACH preamble, or the
DPCCH. Your choice does depend on whether you are using the PRACH or the DPCH mode. Figure 16-88
shows the PRACH data sources that can be used for Eb/No.
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W-CDMA Uplink Concepts
Figure 16-88
PRACH Eb/No Reference Selection
Eb/No Data Sources
Data Source Field
You can calculate the noise values using the following formulas:
Tp = 10 Log[(Cw + Nw) / .001]
Tp = total noise power (dBm)
Cw = linear carrier power (watts) across the 3.84 MHz bandwidth
Nw = linear noise power (watts) across the 3.84 MHz bandwidth
C/N = Eb/No + 10Log(Ref Data Rate/3.84 MHz)
These formulas clearly show the relationship between Eb/No and C/N and their effect on the total noise
power across the 3.84 MHz bandwidth.
DPCH Transmit Power Control by an External Signal
Figure 16-89 illustrates the DPCH power control using an external signal. When the Power Hold is turned
off, the ESG output responds to the power control trigger signal. The transmit power control signal is sent
from the base station and indicates whether to increase or decrease the power level. Increases and decreases
are done in increments of the specified Power Step. Once the power level has reached the specified Max
Power, signals requesting an increase in the power level will be ignored (the power is clipped to Max
Power). There is a 50 chip delay between the base station signal and the RF power response.
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W-CDMA Uplink Concepts
Figure 16-89
586
DPCH External Power Control
Chapter 16
W-CDMA Uplink Digital Modulation for Receiver Test (Option 400)
DPCCH/DPDCH Frame Structure
DPCCH/DPDCH Frame Structure
This section contains graphical representations of W-CDMA frame structures, with associated tables, for
uplink channels.
Figure 16-90
DPCCH/DPDCH Frame Structure
Table 16-11
DPDCH Fields
Channel Bit Rate
(kbps)
Channel Symbol Rate
(ksps)
Spread
Factor
15
15
256
150
10
10
30
30
128
300
20
20
60
60
64
600
40
40
120
120
32
1200
80
80
240
240
16
2400
160
160
Chapter 16
Bits/Frame
Ndata
Bits/Slot
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DPCCH/DPDCH Frame Structure
Table 16-11
DPDCH Fields (Continued)
Channel Bit Rate
(kbps)
Channel Symbol Rate
(ksps)
Spread
Factor
480
480
8
4800
320
320
960
960
4
9600
640
640
Bits/Frame
Bits/Slot
Table 16-12
Bits/Frame
Ndata
Bits/Slot
DPCCH Fields
Channel Bit
Rate (kbps)
Channel
Symbol
Rate
(ksps)
15
15
256
150
10
6
2
0
2
15
15
256
150
10
8
0
0
2
15
15
256
150
10
5
2
1
2
15
15
256
150
10
7
0
1
2
15
15
256
150
10
6
0
2
2
15
15
256
150
10
5
2
2
1
588
Spread
Factor
NTFCI
Npilot
NFBI
NTPC
Chapter 16
17 W-CDMA Downlink Digital Modulation for
Receiver Test (Option 400)
In the following sections, this chapter provides the following information. These features are available only
in E4438C ESG Vector Signal Generators with Option 001/601or 002/602.
This chapter teaches you how to build fully coded W-CDMA downlink modulated signals for testing
mobile/user equipment (UE) designs and provides information on how the W-CDMA downlink format is
implemented within the ESG. The modulation is generated by the signal generator’s internal baseband
generator.
The following list shows the topics covered by this chapter:
•
“Using W-CDMA Downlink” on page 590
•
“Transmit Diversity Overview” on page 598
•
“Configuring for Transmit Diversity and BERT” on page 601
•
“Out-of-Synchronization Testing Overview” on page 612
•
“Configuring for Out-of-Synchronization Testing” on page 613
•
“Compressed Mode Overview” on page 619
•
“Setting Up for a Compressed Mode Signal” on page 622
•
“Making Compressed Mode Signal Measurements” on page 631
•
“Locating Rear Panel Input Signal Connectors” on page 637
•
“Configuring Rear Panel Output Signals” on page 639
•
“W-CDMA Downlink Concepts” on page 644
•
“W-CDMA Frame Structures” on page 651
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Using W-CDMA Downlink
Using W-CDMA Downlink
This section teaches you how to build real time W-CDMA downlink modulation for testing mobile receiver
designs. The modulation is generated by the signal generator’s internal baseband generator. The procedures
in this section build on each other and are designed to be used sequentially.
Configuring the Base Station Setup
1. Press Preset.
2. Press Mode > W-CDMA > Real Time W-CDMA > BS Setup.
This opens a menu where you can adjust the filtering type, chip rate, scrambling code, and
synchronization delay for the simulated base station (see Figure 17-1).
Figure 17-1
Base Station Setup
Use the arrow keys or the knob to highlight the data fields to be edited. Once a field has been
highlighted, pressing the Edit Item softkey enables you to change the value.
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Configuring the Physical Layer
The steps in this procedure build upon the previous procedure.
1. Press Return > Link Control > 5 > Enter.
2. Press PhyCH Setup.
3. Move the cursor to highlight the Off value for DPCH data channel 2.
4. Press Edit Item to toggle the channel on.
The data channel state changes each time you press Edit Item. You can now move the cursor to edit other
data channel fields as well.
5. Press Return.
6. Press Channel State Off On to Off.
Notice that toggling the channel state not only turns off or on the selected physical channel (in this case
DPCH), but also turns off or on all of its data channels, which are shown in the table editor. To turn
individual data channels off or on, repeat steps 2 through 4.
7. Press Channel State Off On to On.
8. Press 6 > Enter. (Or, press the right arrow key.)
9. Press Channel State On Off to On > PhyCH Setup.
This activates the OCNS physical channel, turning on all 16 of its data channels, and accesses the table
editor. Refer to Figure 17-2.
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Using W-CDMA Downlink
Figure 17-2
Physical Layer Table Editor
Each data channel can be edited to have different settings, such as time offsets, as required by 3GPP
TS25.101 for performing some of the functional tests.
Use the arrow keys or the knob to highlight the data fields to be edited. Once a field has been highlighted,
pressing the Edit Item softkey enables you to change the value.
Configuring the Transport Layer
The steps in this procedure build upon the previous procedure.
1. Press Return > 5 > Enter. (Or, press the left arrow key.)
2. Press Transport Setup > TrCH Setup.
This accesses the Downlink Transport type table editor. Refer to Figure 17-3.
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Figure 17-3
Transport Layer Table Editor
Use the arrow keys or the knob to highlight the data fields to be edited. Once a field has been highlighted,
pressing the Edit Item softkey enables you to change the value.
Adjusting Code Domain Power
The tasks in this procedure build upon the previous procedure. This procedure teaches you how to perform
the following tasks:
•
“Scaling to 0 dB” on page 593
•
“Setting Equal Channel Powers” on page 594
Scaling to 0 dB
After changing the relative power level for a channel, the ESG automatically scales the total power to 0 dB,
while preserving the relative channel power levels. Although the displayed total power changes in value as
channel powers are adjusted, the actual total power is maintained at 0 dB. The displayed channel power
levels remain unchanged, reflecting only user-assigned values, so the user can complete the relative power
adjustments. This task teaches you how to update the display to show the normalized relative channel power
for each channel after completing the setup.
1. Press Mode Setup to return to the first-level real time W-CDMA menu.
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Using W-CDMA Downlink
2. Press Link Control > Adjust Code Domain Power > Scale to 0 dB.
The power level displayed for each channel is now changed to show the normalized relative channel power.
The values shown in Figure 17-4 result from activating the OCNS channel, as described earlier in this
section. Notice the displayed power levels before and after the Scale to 0 dB softkey is pressed.
Figure 17-4
Scaling to Zero dB
Displayed Power Levels
Before Scaling to 0 dB
Displayed Power Levels
After Scaling to 0 dB
Setting Equal Channel Powers
This task teaches you how to set the relative power level for all active channels to be equal, for a total power
level of 0 dB. The normalized relative power level of each channel depends on the number of active
channels. This task is an alternative to scaling to 0 dB.
Press Adjust Code Domain Power > Equal Powers.
All active channels have now been set to equal powers. Figure 17-5 shows the displayed normalized relative
power levels after the Equal Powers softkey is pressed with seven active channels. Notice also that the
displayed total power shows a residual value of 0.02 dB due to decimal rounding.
Figure 17-5
Equal Powers
Displayed Power Levels
After Equal Powers
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Using W-CDMA Downlink
Managing Noise
The tasks in this procedure build upon the previous procedure.
The following tasks teach you how to set the overall carrier-to-noise (C/N) ratio for the downlink W-CDMA
setup and to set the Ec/No value for individual physical channels.
•
“Setting the Carrier to Noise Ratio” on page 595
•
“Setting Ec/No” on page 595
Setting the Carrier to Noise Ratio
1. Press Mode Setup to return to the first-level real time W-CDMA menu.
2. Press Link Control > 8 > Enter > Channel State Off On to On.
3. Press PhyCH Setup.
4. Move the cursor to highlight the C/N value field.
5. Press 10 > dB.
NOTE
Noise values less than 10 dB may not be visible on a spectrum analyzer.
You have now set the overall carrier to noise ratio to 10 dB and turned on noise. This is done to apply a
discernible level of noise across the entire channel space.
Setting Ec/No
1. Move the cursor to highlight the Ec Ref field.
2. Press Edit Item > DPCH 2.
3. Move the cursor to highlight the Ec/No value field.
4. Press 15 > dB.
You have now set the Ec/No value for the DPCH 2 channel to 15 dB. Note that modifying the Ec/No value for
a channel will change the overall carrier to noise ratio and the Ec/No value for all other active channels. For
reliable results when making hand calculations to determine or verify Ec/No values, it is recommended that
you first scale the code domain power to 0 dB to display the normalized relative channel power levels (see
“Scaling to 0 dB” on page 593).
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Using W-CDMA Downlink
Generating the Baseband Signal
This procedure builds upon the previous procedure.
Press Mode Setup > W-CDMA Off On to On.
This generates the real time downlink W-CDMA signal. The signal generator experiences a slight delay
while the signal is being built. During this time, Baseband Busy appears on the display. After the signal
generation is completed, the display reads WCDMA On and the WCDMA and I/Q annunciators appear. The
signal is now modulating the RF carrier.
The signal’s configuration data resides in volatile memory and is not recoverable after an instrument preset,
power cycle, or another signal generation.
Applying New Settings
The steps in this procedure build upon the previous procedure.
Signal parameters changes are not always automatically applied to the current signal being transmitted.
When this condition occurs, an annunciator appears informing you that the new changes must be applied to
the signal. This procedure demonstrates how these types of changes are applied to the current signal output.
1. Press Link Control > 5 > Enter.
2. Press PhyCH Setup.
3. Move the cursor to highlight the On value for DPCH data channel 1.
4. Press Edit Item to toggle the channel off.
Notice that with the personality already turned on, as soon as a data channel parameter is changed, the
Apply Needed annunciator appears (see Figure 17-6). This indicates that the new setting has not yet
taken effect in the active baseband signal.
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Figure 17-6
Display Indicates that Apply is Needed
5. Press Apply Channel Setup.
The new setting to the DPCH data channel is now applied to the baseband signal. Notice also that the
Apply Needed annunciator is replaced with Apply Completed.
The Apply Channel Setup softkey is grayed-out until a change occurs that is not automatically applied to the
signal. When such a change occurs, the Apply Needed annunciator appears and the Apply Channel Setup
softkey shows as being active (no longer grayed-out). The new settings are not be applied to the signal until
this softkey is pressed.
Configuring the RF Output
The steps in this procedure build upon the previous procedure.
1. Set the RF output frequency to 2.11 GHz.
2. Set the output amplitude to −10 dBm.
3. Press RF On/Off to On.
The user-defined, real time downlink W-CDMA signal is now available at the RF OUTPUT connector of the
signal generator.
To store this real time I/Q baseband digital modulation state to the instrument state register, see “Saving an
Instrument State” on page 71.
To recall a real time I/Q baseband digital modulation state, see “Recalling an Instrument State” on page 72.
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Transmit Diversity Overview
Transmit Diversity Overview
Transmit diversity is used to diminish the effects of fading by transmitting the same information from two
different antennas. However the data from the second antenna (antenna two) is encoded differently to
distinguish it from the primary antenna (antenna one). The user equipment (UE) must be able to recognize
that the information is coming from two different locations and properly decode the data.
The ESG gives you the ability to perform open-loop transmit diversity testing on UEs. This involves using
two ESGs, one setup as antenna one (non-diversity antenna) and the other configured as antenna two
(diversity antenna).
The implementation of transmit diversity in the ESG follows the 3GPP specifications and employs space
time transmit diversity (STTD) encoding on the primary common control physical channel (P-CCPCH),
page indicator channel (PICH), and the dedicated physical channel (DPCH). The synchronization channel
(SCH) uses time switched transmit diversity (TSTD). The ESG gives you the option of disabling the TSTD
mode for the SCH. The transmit diversity display for the ESG is shown in Figure 17-7.
Figure 17-7
ESG Transmit Diversity Selection Display
Selection when Tx Diversity
is not used
Antenna Selection–TSTD
is Active for the SCH
Antenna Selection–TSTD
is not Active for the SCH on
the Selected Antenna
Transmit Diversity Mode Selection
While the common pilot channel (CPICH) is not STTD encoded, it is affected when transmit diversity is
utilized. The CPICH is transmitted from both antennas (ESGs), but the pre-defined bit sequence for the
CPICH will differ between antenna one and antenna two per the 3GPP specifications.
While STTD encoding transmits the same information through both antennas, the data on antenna two is
transmitted in a different order and some bits are inverted. This is shown in Figure 17-8.
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Figure 17-8
Generic STTD Encoder
Antenna 1
Symbols
STTD Encoded Symbols
In order to simulate two antennas for a transmit diversity application, both ESGs are configured the same
with the exception of one being designated as antenna one and the other as antenna two. The ESG selected
as antenna two will also modify the pilot bits for the dedicated primary common control channel (DPCCH).
TSTD is used only for the SCH and alternately transmits the SCH between the two antennas. Normally the
SCH is transmitted ten percent of the time for each slot of a radio frame. A radio frame is 10 ms long and is
comprised of 15 slots (0–14). During the TSTD transmission, the SCH is broadcasted on antenna one during
even numbered slots and on antenna two during odd numbered slots. This is demonstrated in Figure 17-9.
Figure 17-9
SCH TSTD Operation
The phase for the SCH is also inverted when the P-CCPCH is STTD encoded. When TSTD is turned off, the
SCH is broadcasted in every slot for the selected antenna. This is beneficial for synchronization purposes
when only a single ESG is used.
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Transmit Diversity Overview
Since two antennas are transmitting the same information for a single UE, the W-CDMA signal timing
(frame timing, system frame numbering, etc.) and transmission from both antennas must occur at the same
time. There are two methods you can use to synchronize the transmission between the two ESGs. One
manner of synchronization involves using either an external trigger source or the LF Output on the ESG.
However using either of these two sources does involve several steps in configuring the trigger signal.
The second method of synchronizing is designed into the ESG providing an easier method for setup. This
method utilizes a multiple ESG synchronization trigger whereby the first ESG outputs a synchronization
trigger signal to itself and ESG two. All that is involved in configuring this trigger signal is just selecting it
from the rear output signal menu. This is the method demonstrated in the task “Selecting the Rear Panel
Output Synchronization Signal” on page 605 and “Generating the Baseband Signals and Synchronizing the
ESG Transmissions” on page 609.
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Configuring for Transmit Diversity and BERT
Configuring for Transmit Diversity and BERT
Both ESGs are configured with the same settings. The only difference will be setting one as antenna one and
the other as antenna two. Refer to Figure 17-10 on page 602 for the equipment setup diagram.
In this section, factory preset parameters are used for all channels except for the DPCH. If your needs
require specific settings for the different channels, changing the parameters should not modify the
measurement setup demonstrated here, provided the channels for both ESGs are configured the same.
NOTE
Ensure that both the Out-of-sync Test Off On softkey and the Compressed Mode Off On softkeys
are set to Off. If either of the two features are active, a conflict of settings error message
(error -221) is generated when the antenna selection is made. This will prevent you from
performing the test. Refer to “Generating the Baseband Signal and Activating the
Out-Of-Synchronization Test Feature” on page 617 for instructions on accessing the
Out-of-sync Test Off On softkey and “Setting the Compressed Mode Parameters” on page 627
for the locating the Compressed Mode Off On softkey.
Equipment Set Up
Required Equipment
The following equipment is required to make transmit diversity BER measurements.
•
one E4438C ESG Vector Signal Generator with Options 001/601or 002/602, 400, and UN7
Both ESGs can have Option UN7 (BERT) installed, however it is only required on one of the ESGs.
•
one E4438C ESG Vector Signal Generator with Options 001/601or 002/602 and 400
•
one Agilent 87302C Isolator or an equivalent isolator or combiner
•
an external controller to control the UE being tested
•
an interface level matching circuit for interfacing between the UE being tested and the signal generator
when the UE signal specifications are different from those of the signal generator
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Configuring for Transmit Diversity and BERT
Connection Diagram
Refer to Figure 17-10 and connect the cables for the ESGs and the UE.
Figure 17-10
Transmit Diversity Setup with BERT
Configuring the RF Output for both ESGs
1. Press the Preset hardkey.
2. Set the frequency and amplitude values.
3. Press the RF On/Off hardkey to On.
Steps two and three can be performed either before or after setting the W-CDMA signal parameters.
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Accessing the W-CDMA Modulation Format and Selecting Downlink
Unless stated otherwise, all procedures or tasks begin from the first-level W-CDMA softkey menu accessed
in this procedure.
1. Press Mode > W-CDMA > Real Time W-CDMA.
This accesses the first-level W-CDMA softkey menu. From this display you can elect to set up the base
station parameters (downlink) or the user equipment (UE—uplink).
2. Using the Link Down Up softkey, ensure that Down is highlighted as shown in Figure 17-11.
Figure 17-11
First-Level W-CDMA Softkey Menu
Ensure that Down
is Highlighted (Default)
Current Transmit Diversity Mode
Setting UP Antenna One (ESG One)
Selecting Antenna One Mode
1. Press the BS Setup softkey.
2. Highlight the Tx Diversity field.
3. Press the Edit Item softkey.
This displays the different transmit diversity selections shown in Figure 17-12.
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Figure 17-12
Transmit Diversity Mode Selection Display
Selection when Tx Diversity
is not used
Antenna Selection–TSTD
is Active for the SCH
Antenna Selection–TSTD
is not Active for the SCH on
the Selected Antenna
4. Press the OpenLoop Ant1 softkey.
ESG one is now selected as antenna one. Notice that the display summary for the
Tx Diversity field now shows OpenLoop Ant1. This is shown in Figure 17-13.
Figure 17-13
Antenna One Selection
Transmit Diversity Selection Showing
5. Press the Return hardkey to return to the first-level W-CDMA softkey menu.
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Selecting the Rear Panel Output Synchronization Signal
This task will guide you in selecting the synchronization signal that is used to synchronize the transmission
between the two ESGs. Either ESG can be configured as the trigger source, but to follow the setup diagram,
ESG one is being used as the trigger source.
The signal selected in this task goes from the EVENT 1 connector on ESG one to the PATT TRIG IN
connector on both ESGs.
1. Press More (1 of 2) > Rear Panel Output Setup.
2. Highlight the signal type in the Signal column that corresponds to the Event1 rear panel connector
listed in the Rear Panel ports column. This is demonstrated in Figure 17-14.
Figure 17-14
Highlighted Signal Type for the EVENT 1 Connector
Output Connector
Highlighted
Signal Type
3. Press More (1 of 5) > More (2 of 5) > More (3 of 5) > More (4 of 5) >
Mlt-ESG-Sync-Trigger-Out (DRPS42).
This changes the current highlighted signal type to the multiple ESG synchronization trigger signal. This
is shown in Figure 17-15.
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Figure 17-15
Multiple ESG Synchronization Trigger Signal Selected
Output Connector
Multiple ESG Sync
Trigger Selected
4. Press Return > More (2 of 2) or just press Mode Setup to return to the first-level W-CDMA softkey menu.
Configuring the Signal Parameters
1. Press Link Control > 5 > Enter.
This positions the cursor on the DPCH.
2. Press PhyCH Setup > Ref Measure Setup > 64 kbps.
This selects the 64 kbps reference measurement channel (RMC) as described in the stated 3GPP TS
standard and configures two dedicated channels (DCH, transport channels). If desired, you can adjust the
TFCI bits for the DPCH and the secondary scramble code. Notice that Ref 64 is showing as the data
type for DPCH one. This is demonstrated in Figure 17-16.
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Figure 17-16
64 kbps RMC Selected
64 kbps RMC Selection Showing
3. Press the Mode Setup hardkey to return to the first-level W-CDMA softkey menu.
Setting UP Antenna Two (ESG Two)
All tasks within this section begin at the first-level W-CDMA softkey menu. See “Accessing the W-CDMA
Modulation Format and Selecting Downlink” on page 603 for locating the first-level W-CDMA softkey
menu.
Selecting Antenna Two Mode
1. Press the BS Setup softkey.
2. Highlight the Tx Diversity field.
3. Press the Edit Item softkey.
This displays the different transmit diversity selections, which are shown in Figure 17-17.
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Figure 17-17
Transmit Diversity Mode Selection Display
Selection when Tx Diversity
is not used
Antenna Selection–TSTD
is Active for the SCH
Antenna Selection–TSTD
is not Active for the SCH on
the Selected Antenna
4. Press the OpenLoop Ant2 softkey.
ESG two is now selected as antenna two. Notice that the display summary for the
Tx Diversity field now shows OpenLoop Ant2. This is shown in Figure 17-18.
Figure 17-18
Antenna Two Selection
Transmit Diversity Selection Showing
5. Press the Return hardkey to return to the first-level W-CDMA softkey menu.
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Configuring Signal Parameters
1. Press Link Control > 5 > Enter.
This positions the cursor on the DPCH.
2. Press PhyCH Setup > Ref Measure Setup > 64 kbps.
This selects the 64 kbps reference measurement channel (RMC) as shown in the stated 3GPP TS
standard and configures two dedicated channels (DCH, transport channels). If desired, you can adjust the
TFCI bits for the DPCH and set a secondary scramble code. Notice that Ref 64 is showing as the data
type for DPCH one.
3. Press the Mode Setup hardkey to return to the first-level W-CDMA softkey menu.
Generating the Baseband Signals and Synchronizing the ESG Transmissions
1. Press the W-CDMA Off On softkey to On for both ESG one and two.
This step can be performed at anytime during the setup. The advantage of turning the format on before
setting up the signal, if you have a spectrum analyzer or some other measuring equipment connected, is
you can see the changes as they are made. However you may experience a slight delay in signal
processing while the ESG updates the W-CDMA signal with any changes that are made.
2. On ESG one, press More (1 of 2) > Mlt ESG Sync Trigger.
The output signal for both ESGs are now synchronized and ready to be received by the user equipment
(UE).
NOTE
If any signal parameters are changed after the W-CDMA format is turned on and the Mlt ESG
Sync Trigger softkey is pressed, it may cause a loss of synchronization. You will need to press
the Mlt ESG Sync Trigger softkey after any parameter change is applied to the signal to ensure
proper synchronization between ESG one and two.
Configuring the UE
Using the UE controller, configure the mobile for the call setup procedure to receive the combined ESG
signals, ensuring that the receiver frequency is set to the same as the ESGs.
The UE must be able to demodulate and decode the data from the ESG, and then send this data back to the
ESG for the BERT measurement. The return signal to the ESG must be a TTL or CMOS level signal.
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Making the BERT Measurement
This procedure demonstrates how to make W-CDMA transmit diversity BER measurements. Either ESG
can be configured to perform the BERT measurement as long as it has Option UN7 installed. For this
procedure, we are using ESG one as shown in the setup diagram. For more information on BERT
measurements see Chapter 9, “BERT (Options UN7 and 300),” on page 267.
Selecting the BERT Data Pattern and Total Bits
1. Access the BERT function.
For an ESG with Option UN7 Installed
Press Aux Fctn > BERT > Configure BERT.
For an ESG with Options UN7 and 300 Installed
Press Aux Fctn > BERT > Baseband BERT > Configure BERT.
If the Data softkey does not show that PN9 is the selected data pattern, press
Data > PN9.
The selected PN sequence must match the data PN sequence used on the channel being measured. For
example if the DCH (DTCH) is using PN9 data, then the data selection in the BERT function must also
be PN9.
2. Press Total Bits > 5110 > Bits.
5110 bits (ten times the PN9 data length) at 64 kbps (current data rate for the DCH) takes 0.080 seconds
to test. The value used in this step is merely an example of the number of bits being tested, you can set
the total bits to meet your test needs.
Selecting the BERT Trigger
1. Press Return > Configure Trigger.
If the BERT Trigger softkey does not show Trigger Key as the selected trigger, press
BERT Trigger > Trigger Key.
2. Press Return > BERT Off On to On.
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Configuring for Transmit Diversity and BERT
Starting BERT Measurement
Press the front panel Trigger hardkey to start the BERT measurement. You will see the measurement result
values for Total Bits, Error Bits, and BER on the signal generator display.
NOTE
Chapter 17
If you encounter problems making a BER measurement, check the following:
•
Make sure that the cable connections are properly configured.
•
Make sure that the data pattern for the BER measurement, specified by the Data softkey,
matches the transmitted data pattern.
•
Make sure that the RF is turned on.
•
Make sure that the amplitude is set to the correct level.
•
Make sure that the UE under test is controlled to receive the signal of the specified
carrier frequency.
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Out-of-Synchronization Testing Overview
Out-of-Synchronization Testing Overview
The signal level transmitted by the UE is based on transmit power control (TPC) control information
received from the base station. This control information is contained in the DPCCH. When the DPCCH
power level is significantly reduced, the UE may not be able to decode the TPC bits. When the UE can no
longer decode the TPC bits, it has no way of controlling its power output and should terminate transmission.
When the DPCCH power level is restored, the UE should be able to decode the TPC information and begin
transmitting.
Out-of-synchronization testing is used to determine whether or not a UE can detect that the base station’s
dedicated physical control channel (DPCCH) power has decreased to an undesired level and to also detect
when the DPCCH power returns to a sufficient amplitude. When the UE determines that the DPCCH power
is too low, it is required to discontinue its transmission. When the proper DPCCH power level is received,
the UE is required to begin transmitting. This test is described in the 3GPP specifications.
The ESG provides a method of out-of-synchronization testing by implementing an adjustable discontinuous
transmission (DTX) period for the dedicated physical channel (DPCH). Since the DPCCH is multiplexed
with the dedicated physical data channel (DPDCH) onto the DPCH, injecting a DPCH DTX period
simulates a DPCCH low power condition. The length of the DTX period is determined by an input DTX
gating signal. You are given the option of either having the DTX period occurring on the positive
transition/duty period of the trigger signal or occurring on the negative transition/period. The DTX gating
can be provided by an external source or you can simply use the ESG’s LF Output function as demonstrated
in the procedure “Configuring the DPCH DTX Gating Trigger Signal” on page 618.
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Configuring for Out-of-Synchronization Testing
This section will teach you how to configure the ESG and perform an out-of-synchronization test. While the
test described in this section does not follow the 3GPP conformance test, it will demonstrate the capability
of the UE to determine whether or not it can detect the received DPCCH TPC bits. One of the differences
between this and the conformance test, is that the ESG discontinues the DPCH transmission where the 3GPP
conformance test adjusts the DPCCH power level. The out-of-synchronization test will work only with
DPCH one.
NOTE
Ensure that transmit diversity has been set to None and compressed mode is off. If either of
the two features are active, a conflict of settings error message (error -221) is generated
when the out-of-synchronization mode is turned on. This will prevent you from performing
the test. Refer to “Selecting Antenna One Mode” on page 603 for instructions on accessing
the transmit diversity mode softkey selection menu and “Setting the Compressed Mode
Parameters” on page 627 for the locating the Compressed Mode Off On softkey.
Equipment Set up
Required Equipment
•
one E4438C ESG Vector Signal Generator with Options 001/601or 002/602 and 400
•
an external controller to control the UE under test
•
an Agilent E4440A PSA Spectrum Analyzer or an equivalent instrument
An oscilloscope can be used in place of the spectrum analyzer.
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Configuring for Out-of-Synchronization Testing
Connection Diagram
Refer to Figure 17-19 and connect the cables.
Figure 17-19
Out-of-Synchronization Setup
Setting the RF Output
1. Press the Preset hardkey.
2. Set the frequency and amplitude values.
3. Press the RF On/Off hardkey to On.
Steps two and three can be performed either before or after setting the W-CDMA signal parameters.
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Configuring for Out-of-Synchronization Testing
Accessing the W-CDMA Modulation Format and Selecting Downlink
Unless stated otherwise, all procedures and tasks begin from the first-level W-CDMA softkey menu
accessed in this procedure.
1. Press Mode > W-CDMA > Real Time W-CDMA.
This accesses the first-level W-CDMA softkey menu. From this display you can elect to set up the base
station parameters (downlink) or the user equipment (UE—uplink).
2. Using the Link Down Up softkey, ensure that Down is highlighted as shown in Figure 17-20.
Figure 17-20
First-Level W-CDMA Softkey Menu
Ensure that Down
is Highlighted (Default)
Current Transmit Diversity Mode is Set to None (off)
Setting UP the W-CDMA Signal Parameters
This procedure uses the factory preset parameters for all channels except for the DPCH.
1. Press Link Control > 5 > Enter > PhyCH Setup.
2. Ensure that an item on line one (DPCH one) is highlighted.
3. Press Ref Measure Setup > 12.2 kbps.
This configures DPCH one as a 12.2 kbps reference measurement channel according to the 3GPP
specifications. This reference measurement channel sets up two transport channels (DCH) and the
required DPCH parameters. Ref 12 shows as the data type for DPCH one and is demonstrated in Figure
17-21.
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Configuring for Out-of-Synchronization Testing
Figure 17-21
12.2 kbps RMC Selected
12.2 kbps RMC Selection Showing
If desired, you can adjust the TFCI bits, control the TPC pattern, and set the secondary scrambling code.
4. Press the Mode Setup hardkey to return to the first-level W-CDMA softkey menu.
Selecting the Input DTX Gating Signal Trigger Polarity
1. Press More (1 of 2) > Rear Panel Input Setup > Trigger Polarity Setup.
Notice that there are three different trigger polarity softkeys, two for the compressed mode feature and
one for the DPCH DTX gate signal (out-of-synchronization feature). This is shown in Figure 17-22.
Figure 17-22
Trigger Gating Signal Trigger Polarity Selection
Compressed Mode Trigger
Polarity Selection
Out-of-Sync Mode Trigger
Polarity Selection
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When the trigger polarity selection is positive, the DPCH DTX occurs while the gating signal is high.
The reverse is true when the trigger polarity selection is negative. When the trigger polarity selection is
negative, the DPCH DTX starts when the out-of-synchronization mode is turned on since the absence of
a trigger is interpreted as if the gating signal was low.
2. Press the Mode Setup hardkey to return to the first-level W-CDMA softkey menu.
Generating the Baseband Signal and Activating the Out-Of-Synchronization Test Feature
1. Press the W-CDMA Off On softkey to On.
This step can be performed at anytime during the setup. The advantage of turning the format on before
setting up the signal, if you have a spectrum analyzer or some other measuring equipment connected, is
you can see the changes as they are made. However you may experience a slight delay in signal
processing while the ESG updates the W-CDMA signal with any changes that are made.
2. Press More (1 of 2) > Out-of-sync Test Off On to On.
This prepares the ESG to receive the DPCH DTX trigger gating signal.
Configuring the UE
Using the UE controller, configure the mobile for the call setup procedure to receive the ESG signal
ensuring that the receiver frequency is set to the same as the ESG.
Setting Up the Spectrum Analyzer for Detecting the UE DTX
For this procedure we are using the Agilent E4440A PSA Spectrum Analyzer.
1. Preset the spectrum analyzer.
2. Configure the spectrum analyzer to accept an external 10 MHz frequency reference.
a. Press System > Reference > Freq Ref nn.nnnnn MHz Int Ext until Ext is underscored.
b. Press 10 > MHz.
3. Select the spectrum analysis mode.
Press Mode > Spectrum Analysis.
4. Set the frequency to match the transmission frequency of the UE.
a. Press the Frequency hardkey.
b. Using the numeric keypad, enter the frequency of the UE signal.
5. Set a zero frequency span.
Press Span > Zero Span.
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Configuring for Out-of-Synchronization Testing
6. Set the sweep time for 500 ms.
Press Sweep > 500 > ms.
7. Select external triggering so the measurement begins when the DPCH DTX period starts.
Press Trig > Ext Rear.
Configuring the DPCH DTX Gating Trigger Signal
One of the fundamental features within the ESG is the ability to generate trigger signals using the LF Output
function. In this procedure, we will use the LF Output function to create the DPCH DTX gating signal.
1. Press LF Out > LF Out Source > Function Generator.
2. Press LF Out Waveform > More (1 of 2) > Pulse.
3. Press LF Out Period > 500 > msec.
In accordance with the 3GPP specifications, the UE will cease transmission within a certain amount of
time when the base station’s DPCCH power level decreases by a certain amount. Conversely, the UE
will again begin transmission within a certain amount of time once the DPCCH power level attains the
correct power level. With the ESG, this is simulated by creating a DTX period for the DPCH. The pulse
period time entered allows for a complete cycle where the UE should discontinue and then begin
transmission.
4. Press LF Out Width > 200 > msec.
This is the approximate period of time in which the UE should detect that the ESG’s DPCH has
discontinued transmission, and then turn off its own transmission.
5. Press LF Out Amplitude > 2.5 > Vp.
6. Press LF Out Off On to On.
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Compressed Mode Overview
Compressed Mode Overview
Compressed mode is used when you need to create a discontinuous transmission period (DTX), also called a
transmission gap, so the user equipment (UE) can sample other frequencies. During the DTX period, the UE
can receive control information from either another W-CDMA base station or a GSM base station for a
handoff.
The UE must be able to receive the compressed frames and properly demodulate and decode the data along
with the normal frames. BER and BLER measurements are made on the data to ensure proper UE operation.
The ESG facilitates this type of testing by transmitting fully coded transport channels (DCH) for
compressed, normal, or a combination of compressed and normal frames. These fully coded channels can
automatically be configured using the provided reference measurement channels (RMC) or you can set your
own custom configurations. The ESG supports the following 3GPP defined DPCH channel configurations
for compressed mode:
•
12.2 kbps
•
64 kbps
•
144 kbps
•
384 kbps
•
AMR 12.2 kbps
•
UDI IDSN 64 kbps
With both the fully coded transport channels and the wide choice of RMCs, you are able to fully test the UE
for proper demodulation and decoding using BER testing. For more information on the supported RMCs,
see “Reference Measurement Channels” on page 644.
The compressed mode in the ESG complies with the 3GPP specifications and is very flexible with many
adjustable parameters. You can have one or two transmission gaps. When two gaps are used, each gap can
have a different length and operate using the single or double frame method. The double frame method uses
slots from two compressed frames to create one transmission gap. Table 17-1 describes some of the
parameters that are available for the compressed mode.
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Compressed Mode Overview
Table 17-1
Downlink Compressed Mode Parameters
Name
Definition
Transmission gap pattern repetition count (TGPRC)
Number of transmission gap patterns within the
transmission gap pattern sequence.
Transmission gap connection frame number (TGCFN) CFN of the first compressed frame of the first
pattern within the transmission gap pattern
sequence.
Transmission gap slot number
(TGSN)
Slot number of the first transmission gap within
the first radio frame of the transmission gap
pattern.
Transmission gap length 1
(TGL1)
Duration of the first transmission gap within the
transmission gap pattern.
Transmission gap length 2
(TGL2)
Duration of the second transmission gap.
Transmission gap duration
(TGD)
This is the distance, measured in slots, from the
beginning of the first transmission gap to the
beginning of the second transmission gap.
Transmission gap pattern length 1
(TGPL1)
Duration of first transmission gap pattern that
includes TGL1/2.
Transmission gap pattern length 2
(TGPL2)
Duration of the second transmission gap pattern
that includes TGL1/2.
Stop connection frame number
(Stop CFN)
CFN of the last radio frame.
Transmission gap pattern sequence identifier (TGPSI) This identifies the currently selected transmission
gap pattern sequence. Only one TGPSI is
supported at this time.
Transmission gap pattern sequence
(TGPS)
This lets you select whether or not to transmit the
current TGPSI. Active it will be transmitted,
inactive it will not be transmitted.
CM Method: SF/2 (spread factor divided by two) or
Puncturing
This determines the data processing mode used to
create the gaps.
Frame Struct: A or B
A: Optimizes the gap length.
B: Optimizes the power control.
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Compressed Mode Overview
The ESG offers two different compressed mode methods for transmitting compressed frames. This is shown
as CM Method: SF/2 (spread factor divided by two) or Puncturing in Table 17-1. SF/2 reduces the spread
factor of the compressed frame by half; puncturing reduces the amount of transmitted data by eliminating
bits.
The ESG also supports the DPCH slot sub-formats, denoted in the specifications by the slot format number
with an ‘A’ or ‘B’, that are used during compressed frame transmission. The sub-format used is dependent
on the selected compressed mode method. The ESG automatically selects the correct sub-format for the
current slot format when you select the compressed mode method. For example if you were using slot
format 3, which includes the sub-formats 3A and 3B, and selected the SF/2 compressed mode method, the
ESG would use sub-format 3B. If you were to select puncturing as the compressed mode method, then the
ESG would automatically select sub-format 3A.
Another feature of the ESG compressed mode gives you the ability to select the different frame structures
utilized during compressed frame transmission. Frame structure ‘A’ optimizes the DTX periods by not
transmitting any power control information (TPC field) during this time. Frame structure ‘B’ optimizes for
power control by inserting power control information during the first DTX slot for each transmission gap.
Both frame structures transmit the pilot bits during the last slot for each transmission gap.
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Setting Up for a Compressed Mode Signal
Setting Up for a Compressed Mode Signal
Using the compressed mode turns the ESG ALC feature off. To maintain amplitude accuracy, it is
recommended that you perform a power search. This is demonstrated in the task, “Performing a Manual
Power Search” on page 629.
The signal parameters set in this section are used for both setups shown in the Equipment Setup section.
NOTE
Ensure that transmit diversity has been set to None and the Out-of-sync Test Off On softkey is
set to Off. If either of the two features are active, a conflict of settings error message
(error -221) is generated when compressed mode is turned on. This will prevent you from
using the feature. Refer to “Selecting Antenna One Mode” on page 603 for instructions on
accessing the transmit diversity mode softkey selection menu and “Generating the
Baseband Signal and Activating the Out-Of-Synchronization Test Feature” on page 617 for
instructions on accessing the Out-of-sync Test Off On softkey.
Equipment Setup
Required Equipment for Measuring the DPCH Symbol Power
•
one E4438C ESG Vector Signal Generator with Options 001/601or 002/602 and 400
•
one Agilent E4440A PSA Spectrum Analyzer with Options B7J and BAF or an equivalent instrument
Required Equipment for BERT Measurements
•
one E4438C ESG Vector Signal Generator with Options 001/601or 002/602, 400, and UN7
•
an external controller to control the UE being tested
•
an interface level matching circuit for interfacing between the UE being tested and the signal generator
when the UE signal specifications are different from those of the signal generator
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Setting Up for a Compressed Mode Signal
Connection Diagram for Measuring the DPCH Symbol Power
Refer to Figure 17-23 and connect the cables for the ESG and PSA (spectrum analyzer).
Figure 17-23
Compressed Mode Setup for a Symbol Power Measurement
Connection Diagram for BERT Measurements
Refer to Figure 17-24 and connect the cables for the ESG and the UE.
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Setting Up for a Compressed Mode Signal
Figure 17-24
Compressed Mode Setup for BERT
Setting the RF Output
1. Press the Preset hardkey.
2. Set the frequency and amplitude values.
3. Press the RF On/Off hardkey to On.
Steps two and three can be performed either before or after setting the W-CDMA signal parameters.
However they must be done before the power search is performed in the task, “Performing a Manual Power
Search” on page 629.
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Setting Up for a Compressed Mode Signal
Accessing the W-CDMA Modulation Format and Selecting Downlink
Unless stated otherwise, all procedures and tasks begin from the first-level W-CDMA softkey menu
accessed in this procedure.
1. Press Mode > W-CDMA > Real Time W-CDMA.
This accesses the first-level W-CDMA softkey menu. From this display you can elect to set up the base
station parameters (downlink) or the user equipment (UE—uplink). See Figure 17-25 for the first-level
W-CDMA softkey menu display.
2. Using the Link Down Up softkey, ensure that Down is highlighted as shown in Figure 17-25.
Figure 17-25
First-Level W-CDMA Softkey Menu
Ensure that Down
is Highlighted (Default)
Current Transmit Diversity Mode is Set to None (off)
Setting Up the W-CDMA Signal Parameters
This procedure uses the factory preset parameters for all channels except for the DPCH.
1. Press Link Control > 5 > Enter > PhyCH Setup.
2. Ensure that an item on line one (DPCH one) is highlighted.
The compressed mode feature operates with only DPCH one. If you were to try use DPCH two by itself
or in unison with DPCH one, an error message is generated.
3. Press Ref Measure Setup > 12.2 kbps.
This configures DPCH one as a 12.2 kbps reference measurement channel according to the 3GPP
specifications. This reference measurement channel sets up two transport channels (DCH) and the
required DPCH parameters. Ref 12 now shows as the data type for DPCH one and is demonstrated in
Figure 17-26.
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Figure 17-26
12.2 kbps RMC Selected
12.2 kbps RMC Selection Showing
If desired, you can change the TFCI bits, control the TPC pattern, and select the secondary scrambling
code.
4. Press the Mode Setup hardkey to return to the first-level W-CDMA softkey menu.
Generating the Baseband Signal
Press the W-CDMA Off On softkey to On.
This step can be performed at anytime during the setup. The advantage of turning the format on before
setting up the signal, if you have a spectrum analyzer or some other measuring equipment connected, is you
can see the changes as they are made. However you may experience a slight delay in signal processing while
the ESG updates the W-CDMA signal with any changes that are made.
Configuring Compressed Mode
Selecting the Rear Panel Output Trigger Signal
Performing this task is not required if you are performing BERT measurements. A rear panel output signal is
used to trigger an instrument, so it begins measuring the RF output signal at a certain point.
1. Press More (1 of 2) > Rear Panel Output Setup > More (1 of 5) > More (2 of 5) >
DPCH Compressed Frame Indicator (DRPS32).
This enables an output trigger signal at the rear panel EVENT 1 connector when the compressed frame is
transmitted.
2. Press the Mode Setup hardkey to return to the first-level W-CDMA softkey menu.
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Setting the Compressed Mode Parameters
1. Press Link Control > 5 > Enter > Compressed Mode Setup.
Notice that the cursor is already showing in the compressed mode table editor. This means you can
immediately start editing parameters upon entering the compressed mode display. This is unlike the
uplink where another softkey needs to be pressed before the cursor is displayed in the table editor.
The compressed mode feature is accessible only when the DPCH (5) is highlighted. The Compressed
Mode Setup softkey is grayed-out when any other channel is selected.
2. Set slot eight of the frame as the starting slot for the first transmission gap.
a. Move the cursor to highlight the TGSN field.
b. Press 8 > Enter.
This sets the first compressed frame to have eight slots (0–7) of data with slot eight marking the
beginning of the first transmission gap.
3. Set the first transmission gap length which is expressed as a number of slots.
a. Move the cursor to highlight the TGL1 field.
b. Press 14 > Enter.
Out of the 15 slots per frame, the standard specifies that seven of them can be used as discontinuous
transmission (DTX) slots. However the total gap length can be spread over two frames. The value 14
denotes 14 DTX slots, which spans 2 frames. This is called the double-frame method. When TGSN is ≤
8 and TGL is ≤ 7, then the DTX slots are contained in one frame forming the single-frame method.
4. Set the second transmission gap length which is expressed as a number of slots.
a. Move the cursor to highlight the TGL2 field.
b. Press 3 > Enter.
For the second transmission gap, the single frame method is used.
5. Set the spacing between the first and second transmission gaps expressed as a number of slots.
a. Move the cursor to highlight the TGD field.
b. Press 37 > Enter.
6. Set the duration of the first transmission gap pattern which is expressed as a number of frames.
a. Move the cursor to highlight the TGPL1 field.
b. Press 6 > Enter.
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7. Set the duration of the second transmission gap pattern which is expressed as a number of frames.
a. Move the cursor to highlight the TGPL2 field.
b. Press 4 > Enter.
8. Enable the compressed frames.
a. Move the cursor to highlight the TGPS field.
b. Press Edit Item > Active.
9. Press the Compressed Mode Off On softkey to On.
This softkey turns the compressed mode feature on, but it does not cause the compressed frame
transmission to begin. Compressed frames are not transmitted until the ESG receives a trigger signal.
This is demonstrated in the task, “Setting the Frame Power Offset and Triggering the Compressed Frame
Function” on page 630.
Notice that when compressed mode is turned on, the ALC feature of the ESG is turned off. This is
indicated by the ALC OFF annunciator showing in the display and shown in Figure 17-27.
The Compressed Mode Off On softkey can be set to On at any time, however doing it at the end applies the
changes to the baseband signal, so you do not have to press the
Apply Channel Setup softkey. This just decreases the number of required key presses during the signal
setup. But if changes are made to the compressed mode after the feature is turned on, the Apply
Needed annunciator may appear. When the annunciator appears, this means that you must press the
Apply Channel Setup softkey to apply the changes to the signal.
Figure 17-27 shows the compressed mode display once all parameters from this procedure are
completed.
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Figure 17-27
Completed Compressed Mode Display
Page 1
Page 2
Performing a Manual Power Search
This task builds upon the previous task, “Setting the Compressed Mode Parameters” on page 627.
The ALC feature is disabled when compressed mode is used (Compressed Mode Off On softkey set to On), and
it is recommended that a manual power search is performed to ensure the correct output power level. See the
section “Special Power Control Considerations When Using Compressed Mode” on page 650 for more
information.
This task will guide you in configuring and performing a manual power search. If desired, you can adjust the
power search settings to meet your individual test needs.
1. Press Amplitude > Power Search > Power Search Reference Fixed Mod to Mod.
Mod references the power search on the rms value of the I/Q modulation, whereas fixed uses a 0.5 volt
reference during the power search operation.
From this current softkey menu, you can make adjustments to the other power search parameters to meet
your test needs.
2. Press Return > Do Power Search.
The ESG has now performed a power adjustment for the current carrier frequency. If you change
frequencies or the RF output power level, the power adjustment will have to be done again.
3. Press the Return hardkey to access the previous compressed mode menu.
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Setting Up for a Compressed Mode Signal
Setting the Frame Power Offset and Triggering the Compressed Frame Function
NOTE
If you are using the spectrum analyzer setup shown in the section “Connection Diagram for
Measuring the DPCH Symbol Power” on page 623, it is best to perform Step 3 once you
have completed the spectrum analyzer setup in the section, “Measuring the DPCH Symbol
Power” on page 631. Because this is a demodulation measurement, the spectrum analyzer
needs to capture the DPCH before DTX periods are incorporated. If the spectrum analyzer
encounters a DTX period while making a demodulation measurement, it will not recognize
the DPCH transmission.
1. Set the compressed frame power relative to the non-compressed (normal) frames.
a. Move the cursor to highlight the PwrOffs field.
b. Press 6 > dB.
This enables you to compensate for reduced spreading gain. The higher power level makes the
compressed frames easier to view.
2. Press the Apply Channel Setup softkey.
3. Press the Compressed Mode Start Trigger softkey.
The compressed mode function terminates when the Compressed Mode Stop Trigger softkey is pressed, an
external stop trigger signal is received, or when the Apply Channel Setup softkey is pressed. You can also stop
the transmitted compressed mode signal after a set number of transmissions by changing the TGPRC field
from Infinity to the desired number of repetitions. To restart the compressed mode function, just press
the Compressed Mode Start Trigger softkey or send an external start trigger signal.
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Making Compressed Mode Signal Measurements
Making Compressed Mode Signal Measurements
Measuring the DPCH Symbol Power
This procedure will guide you through setting up a spectrum analyzer for demodulating the compressed
DPCH that was configured in the previous procedures. While the main steps are generically written, the
substeps are written specifically for the E4440A PSA. The setup diagram for this procedure is shown in
Figure 17-23 on page 623.
Configuring the Spectrum Analyzer
1. Preset the spectrum analyzer.
2. Select the W-CDMA measurement mode.
Press Mode > W-CDMA.
3. Set the spectrum analyzer to receive a base station signal.
Press Mode Setup > Radio > Device BTS MS until BTS is underscored.
4. Set the spectrum analyzer frequency to match the transmission frequency of the ESG.
a. Press the Frequency hardkey.
b. Using the numeric keypad, enter the carrier frequency of the ESG signal.
5. Select the code domain measurement.
Press Measure > More 1 of 3 > Code Domain.
6. Set a span that lets you view the channels.
Press Span > Scale/Div > 64 > Enter.
Figure 17-28 shows the current spectrum analyzer display. If the display does not show the channels,
press the Restart hardkey to perform another measurement.
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Making Compressed Mode Signal Measurements
Figure 17-28
DPCH Selected on PSA
DPCH
7. Set the spectrum analyzer so it measures the DPCH symbol power.
a. Press Meas Setup > Symbol Rate > 30 > ksps.
This sets the DPCH symbol rate for the 12.2 kbps RMC data rate and matches the ESG DPCH
symbol rate shown in Figure 17-29
b. Press Code Number > 10 > Enter.
This sets the channel code branch that the DPCH is using and is associated with the with the SF for
the symbol rate of 30 ksps (3.84 Mcps / 30 ksps = SF 128).
The code number is found on the ESG DPCH setup display and is shown in Figure 17-29.
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Making Compressed Mode Signal Measurements
Figure 17-29
DPCH Signal Parameters
DPCH Channel Code
DPCH Symbol Rate
8. Select a frame capture interval that will display the DPCH compressed pattern.
Press More 1 of 3 > Capture Intvl > 8 Frame (Long Mode).
Notice that the display changes from code domain to symbol power.
9. Zoom in on the symbol power display
Press the Zoom hardkey.
10. Trigger the spectrum analyzer from the rear panel input using the supplied ESG DPCH compressed
frame trigger signal.
Press More 2 of 3 > Trig Source > Ext Rear.
NOTE
If you have not started the triggering for the ESG compressed mode signal, press the
Compressed Mode Start Trigger softkey on the ESG.
11. Start the measurement for the symbol power.
Press the Restart hardkey.
The spectrum analyzer may take a few moments to display the DPCH symbol power. Depending on
which compressed frame triggers the spectrum analyzer measurement, your display may differ from the
one showing in Figure 17-30. However the characteristics of the signal as depicted in Figure 17-30 still
apply.
Chapter 17
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Making Compressed Mode Signal Measurements
Figure 17-30
Compressed DPCH Signal
DPCH Spread Factor 128 (27) and Code Branch 10
Compressed Slots
14 DTX Slots
3 DTX Slots
Normal Frames
12. Use a marker to measure the different displayed symbol power levels.
a. Press Marker > Trace > Symbol Power.
b. Use the RPG knob to position the cursor at the desired location.
You can make further signal measurements on the PSA such as measuring the number of slots for a section
on the display. This is accomplished with Meas Interval x Slots and the
Meas Offset x Slots softkeys located in the Meas Setup hardkey menu. This can help you verify the signal
parameters that were set on the ESG.
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W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
Making Compressed Mode Signal Measurements
Making the BERT Measurement
This procedure demonstrates how to make W-CDMA compressed signal BER measurements. Option UN7
must be installed on the ESG. The setup diagram for this procedure is shown in Figure 17-24 on page 624.
For more information on BERT measurements see Chapter 9, “BERT (Options UN7 and 300),” on page 267.
Configuring the UE
Using the UE controller, configure the mobile for the call setup procedure to receive the ESG signal,
ensuring that the receiver frequency is set to the same as the ESG.
The UE must be able to demodulate and decode the data from the ESG, and then send this data back to the
ESG for the BERT measurement. The return signal to the ESG must be a TTL or CMOS level signal.
Selecting the ESG BERT Data Pattern and Total Bits
1. Access the BERT function.
For an ESG with Option UN7 Installed
Press Aux Fctn > BERT > Configure BERT.
For an ESG with Options UN7 and 300 Installed
Press Aux Fctn > BERT > Baseband BERT > Configure BERT.
If the Data softkey does not show that PN9 is the selected data pattern, press
Data > PN9.
The selected PN sequence must match the data PN sequence used on the channel being measured. For
example if the DCH (DTCH) is using PN9 data, then the data selection in the BERT function must also
be PN9.
2. Press Total Bits > 5110 > Bits.
5110 bits (ten times the PN9 data length) at 12.2 kbps (current data rate for the DCH) takes
0.419 seconds to test. The value used in this step is merely an example of the number of bits being tested,
you can set the total bits to meet your test needs.
Selecting the ESG BERT Trigger
1. Press Return > Configure Trigger.
If the BERT Trigger softkey does not show Trigger Key as the selected trigger, press
BERT Trigger > Trigger Key.
2. Press Return > BERT Off On to On.
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Making Compressed Mode Signal Measurements
Starting the ESG BERT Measurement
Press the front panel Trigger hardkey to start the BERT measurement. You will see the measurement values
for the Total Bits, Error Bits, and BER on the signal generator display.
NOTE
636
If you encounter problems making a BER measurement, check the following:
•
Make sure that the cable connections are properly configured.
•
Make sure that the data pattern for the BER measurement, specified by the Data softkey,
matches the transmitted data pattern.
•
Make sure that the RF is turned on.
•
Make sure that the amplitude is set to the correct level.
•
Make sure that the UE under test is controlled to receive the signal of the specified
carrier frequency.
Chapter 17
W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
Locating Rear Panel Input Signal Connectors
Locating Rear Panel Input Signal Connectors
One feature of the W-CDMA downlink format is the ease in which you can determine the correct rear panel
input connector for a particular signal application. The input signal type changes depending on whether you
are in the compressed mode, performing the out-of-synchronization test, or doing transmit diversity, which
is the same as the standard (default) downlink mode. This section guides you through the softkey menus to
where you can view the information.
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Down (default).
2. Press More (1 of 2) > Rear Panel Input Setup.
The information shown in the text area, displays the connector and the type of input signal it accepts. For
example, the BBG Reference in listing (BASEBAND GEN REF IN connector) in the Rear Panel
Ports column accepts a baseband generator (BBG) chip clock signal. Figure 17-31 shows the different
input signal to connector displays.
Chapter 17
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W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
Locating Rear Panel Input Signal Connectors
Figure 17-31
Rear Panel Input Signal Connector Information
Default Input Signal
(Tx Diversity) Display
BBG Reference in
Signal Type
Out of Synchronization Test
Input Signal Display
NOTE: The Out of Synchronization Test
must be on to see this display
Compressed Mode Input
Signal Display
NOTE: Compressed Mode must
be on to see this display
3. To exit this display, press either Mode Setup to return to the first-level W-CDMA softkey menu or press
Return until you come to the desired softkey menu/display.
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Chapter 17
W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
Configuring Rear Panel Output Signals
Configuring Rear Panel Output Signals
The W-CDMA downlink format provides you the ability to configure output signals for the various rear
panel output connectors. This lets you control trigger signals based on your needs. Unlike the rear panel
input signals, the ESG does not have to be in a particular mode to select any of the rear panel output signals.
However the correct feature (transmit diversity, compressed mode, out-of-synchronization testing, etc.) must
be active before some signals are available at the rear panel. For example, if you select the DPCH Compressed
Frame Indicator(DRPS32) as an output trigger signal, the ESG must be transmitting a compressed mode signal
before this rear panel trigger is realized. This section guides you through the softkey menus to where you
can configure your signals.
Accessing the Rear Panel Output Signal Menu
1. Press Mode > W-CDMA > Real Time W-CDMA > Link Down Up to Down (default).
This is the first-level W-CDMA softkey menu.
2. Press More (1 of 2) > Rear Panel Output Setup.
Selecting an Output Signal
1. Using the arrow keys, highlight the item in the Signal column that corresponds to the Event2
connector listed in the Rear Panel Ports column. This is shown in Figure 17-32.
Figure 17-32
Event2 Connector
Selection
Chapter 17
Output Connector Selection
Highlighted
Item
639
W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
Configuring Rear Panel Output Signals
2. Press More (1 of 5) > More (2 of 5) > DPCH data-clk(DRPS28).
Notice that in row two of the table editor under the column Signal, the text
SFN reset-signal(DRPS5) changed to DPCH data-clk(DRPS28). This corresponds to the
Event2 connector listed in the Rear Panel ports column. Figure 17-33 shows what the ESG
display looks like after the DPCH data-clock selection is made.
Figure 17-33
Output Trigger Signal Selection
DPCH data-clk(DRPS28)
Softkey
DPCH data-clock
Selected
To exit this display, press either Mode Setup to return to the first-level W-CDMA softkey menu or press
Return until you come to the desired softkey menu/display.
Deselecting an Output Signal
This procedure builds upon the previous procedure Selecting an Output Signal.
1. Press More (3 of 5) > More (4 of 5).
2. Highlight the Event2 connector listing.
3. Press NONE(DRPS0).
Notice that the output signal selection listed in the Signal column has changed to None(RPSO) and is
shown in Figure 17-34. The none indicates that there is no signal output selected for the corresponding
connector.
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Configuring Rear Panel Output Signals
Figure 17-34
Deselected Signal
NONE(DRPS0)
Softkey
Now, No Output
Signal is Selected
Rear Panel Output Signal Descriptions
Table 17-2 describes the different downlink rear panel output signals available on the ESG. The DRPSxx
designator, shown in parenthesis, refers to the remote SCPI command parameter that corresponds to the
particular softkey selection. For example, the designator DRPS4 refers to the SCPI command parameter for
a 3.84 MHz chip-clock signal.
Table 17-2
Downlink Rear Panel Output Signals
Signal Name
Description
3.84 MHz chip-clk (DRPS4)
Assigns a 3.84 MHz chip clock signal to the selected
rear panel output port.
SFN reset-signal (DRPS5)
Assigns a system frame number (SFN) reset-signal to
the selected rear panel output port.
SFN sync pulse (DRPS6)
Assigns a system frame number (SFN) synchronization
pulse to the selected rear panel output port.
SCH slot pulse (DRPS10)
Assigns the synchronization channel pulse to the
selected rear panel output port.
10ms Frame pulse (DRPS11)
Assigns the 10 millisecond frame pulse to the selected
rear panel output port.
80ms Frame pulse (DRPS13)
Assigns the 80 millisecond frame pulse to the selected
rear panel output port.
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Configuring Rear Panel Output Signals
Table 17-2
Downlink Rear Panel Output Signals
Signal Name
Description
DPDCH data-clk withDTX (DRPS20)
Assigns the dedicated physical data channel (DPDCH)
data clock to the selected rear panel output port. This is
a continuous pulsed signal that is not affected by the
transmission gaps incurred during compressed frame
operation.
DPCCH TPC data-clk (DRPS21)
Assigns the dedicated physical control channel
(DPCCH) transmit power control (TPC) data clock to
the selected rear panel output port.
DPCCH TFCI data-clk (DRPS22)
Assigns the dedicated physical control channel
(DPCCH) transmit format combination indicator
(TFCI) data clock to the selected rear panel output port.
DPCCH Pilot data-clk (DRPS23)
Assigns the dedicated physical control channel pilot
data clock to the selected rear panel output port.
DPCH data-stream (DRPS24)
Assigns the DPCH data stream to the selected rear
panel output port (prior to spreading and scrambling).
DPCH TimeSlot pulse (DRPS25)
Assigns the DPCH timeslot pulse to the selected rear
panel output port.
DPCH 10ms Frame Pulse (DRPS26)
Assigns the DPCH 10 millisecond frame pulse to the
selected rear panel output port.
DPCH data-clk (DRPS28)
Assigns the DPCH data clock to the selected rear panel
output port.
DPDCH data-clk withOutDTX (DRPS30)
Assigns the dedicated physical data channel (DPDCH)
data clock to the selected rear panel output port. This
signal provides DTX periods that reflects the absence
of DPDCH data during the transmission gaps that are
incurred during compressed frame operation. When
compressed mode is disabled, this signal performs the
same function as the DRPS20 signal.
DPCH Compressed Frame Indicator (DRPS32)
Assigns the DPCH compressed frame indicator signal
to the selected rear panel output port.
DPCH Gap Indicator (DRPS33)
Assigns the DPCH gap indicator signal to the rear
panel output port for compressed mode.
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Configuring Rear Panel Output Signals
Table 17-2
Downlink Rear Panel Output Signals
Signal Name
Description
PICH data (DRPS35)
Assigns paging indicator channel (PICH) data to the
selected rear panel output port.
PICH TimeSlot pulse (DRPS36)
Assigns the paging indicator channel (PICH) timeslot
pulse to the selected rear panel output port.
PICH 10ms FramePulse (DRPS37)
Assigns the paging indicator (PICH) 10 millisecond
frame pulse to the selected rear panel output port.
P-CCPCH data-clk (DRPS38)
Assigns the primary common control physical channel
(P-CCPCH) data clock to the selected rear panel output
port.
P-CCPCH data (DRPS39)
Assigns the primary common control physical channel
(P-CCPCH) data to the selected rear panel output port.
DPCH ChipARB frame pulse (DRPS40)
Assigns the DPCH chip ARB frame pulse data to the
selected rear panel output port.
DPCH TPC bits out (DRPS41)
Assigns the DPCH transmit power control (TPC) bits
to the selected rear panel output port.
Mlt-ESG-Sync Trigger-Out (DRPS42)
Used to instantly synchronize the output signals of
multiple ESGs while performing open-loop transmit
diversity testing.
Chapter 17
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W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
W-CDMA Downlink Concepts
W-CDMA Downlink Concepts
DPCH Coding Block Diagram
Reference Measurement Channels
Real time W-CDMA provides fully coded reference measurement channels (RMC) at 12.2, 64, 144, and
384 kbps, the AMR at 12.2 kbps, and the UDI ISDN at 64 kbps. Along with user defined parameters, all four
RMCs, the AMR 12.2, and the UDI ISDN are supported for use with the compressed mode feature.
The signal generator provides one-button setup capabilities for transport channel configuration. The
dedicated physical channel DCH (downlink) is automatically setup by pressing the Ref Measure Setup softkey
(or sending the appropriate SCPI commands) and then selecting the desired data type. To activate the Config
Transport softkey, one of the reference measurement rates must be selected or the DPCH Data field value
must be set to Transport CH.
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W-CDMA Downlink Concepts
Table 17-3 describes the downlink RMC configurations generated by pressing the Ref Measure Setup softkey
after the signal generator has been preset. Transport channel parameters can be modified in a table editor by
pressing the Config Transport softkey, then moving the cursor to the desired data field and pressing Edit Item.
DPCH parameters can be individually modified in a table editor by pressing PhyCH Setup, then moving the
cursor to the desired data field and pressing Edit Item.
Table 17-3
The Downlink RMC Predefined DPCH Configuration
Parameter
DPCH Values at Specified Reference Measurement Channel
Channel Rate
12.2 kbps
64 kbps
144 kbps
384 kbps
AMR 12.2 kbps
UDI ISDN 64 kbps
Power
0.00 dB
0.00 dB
0.00 dB
0.00 dB
0.00 dB
0.00 dB
Channel Codea
6
6
6
6
6
6
SecSrc Code OS
0
0
0
0
0
0
TPC Pat Steps
1
1
1
1
1
1
Datab
Ref 12
Ref 64
Ref 144
Ref 384
AMR 12
ISDN
Symbol Ratec
30.00 ksps
120.0 ksps
240.0 ksps
480.0 ksps
30.0 ksps
120.0 ksps
TFCI Pattern
00000000
00000000
00000000
00000000
00000000
00000000
TPC Pattern
Up/Down
Up/Down
Up/Down
Up/Down
Up/Down
Up/Down
Slot Format
11
13
14
15
8
13
Time Offset
0
0
0
0
0
0
a. ESG Channel # 1 default shown. Default channel code for Channels 2 through 4 are based on the equation: Default
Channel Code = (Channel #) + 5.
b. If a transport configuration parameter is changed using the Config Transport
softkey and the table editor, the Data field reverts to Transport CH, showing that it no longer contains a specified
reference measurement channel.
c. Symbol rate is not user-selectable. It is coupled to slot format. To change the symbol rate, use the appropriate slot format.
Chapter 17
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W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
W-CDMA Downlink Concepts
Scramble Codes
The real time I/Q baseband 3GPP W-CDMA personality implements scrambling codes for downlink OCNS
and DPCH channels in compliance with the 3GPP specifications. This is done through the use of the
Scrambling Code (primary scramble code) field, located in the BS setup menu, and the SecScr Code
OS (secondary scramble code offset) fields located in the OCNS and DPCH Physical Channel Setup menus.
These fields are linked so that an entry to any field affects the actual scramble code. To better understand the
relationship, refer to the following formula:
n = ( 16 × i ) + k
Table 17-4
Where n = scramble code
Range: 0 to 8191
i = Primary Scrambling Code field input
Range 0 to 511
k = SecScr Code OS field input
Range: 0 to 15
The primary and secondary sets are determined by the SecScr Code OS field values. If the SecScr Code
OS field value is zero, then the scramble code is in the primary set. Any non-zero entry enables the
secondary set. The SecScr Code OS field value has a range of
0 through 15.
A primary scramble code is the product of the Scrambling Code field value and 16. Therefore, the
primary scramble code set contains all the multiples of 16, from 0 through 8176.
A secondary scramble code is the sum of the non-zero SecScr Code OS field value and the primary
scramble code. The secondary scramble code set uses the numbers in between the multiples of 16.
Thus, all numbers from 0 through 8191 are available for scramble codes.
Refer to the following for examples of scramble codes generated with the primary and secondary sets:
n = ( 16 × i ) + k
Table 17-5
Where n = scramble code
i = Scrambling Code field input
k = SecScr Code OS field input
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W-CDMA Downlink Concepts
Table 17-6
A: Primary set
B: Secondary set
i=6
i=8
k=0
k=7
n = 96
n = 135
W-CDMA AWGN Measurements and Bandwidths
The AWGN (additive white Gaussian noise) feature produces a noise signal across a 7.68 MHz bandwidth
(2x the W-CDMA 3.84 MHz bandwidth) and lets you enter values that adjust the noise level across this
spectrum. To resolve the noise signal’s effect on the W-CDMA signal, the ESG also displays noise values
across the W-CDMA 3.84 MHz bandwidth. In addition, the AWGN feature shows the bandwidth of the
noise signal during the period when it has a flat frequency response. This is called the flat-noise bandwidth.
Figure 17-35 shows the different noise settings/values as they appear on the W-CDMA AWGN display
along with a graphical representation of the noise signal showing the different bandwidth features.
Chapter 17
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W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
W-CDMA Downlink Concepts
Figure 17-35
Noise Measurement Bandwidths
AWGN 7.68 MHz Entries
AWGN 3.84 MHz Values
Flat Noise Bandwidth
As shown in Figure 17-35, the noise signal is added to the W-CDMA signal across the entire W-CDMA
signal spectrum. The ESG gives you two ways to control the noise level. You can set the noise using either
Ec/No (energy per chip to noise power density ratio) or C/N (carrier power to noise power ratio). Any
adjustment to either noise parameter, Ec/No or C/N, will affect the other; they are not mutually exclusive.
Ec/No lets you set the noise power relative to the power of a channel, versus setting the noise relative to the
carrier power (C/N). For example, if you select the P-CCPCH (called a reference channel), the power level
of this channel is used in the ratio for Ec/No. Figure 17-36 shows the downlink channel selections for Ec/No
and the channel reference fields.
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Chapter 17
W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
W-CDMA Downlink Concepts
Figure 17-36
Ec/No Reference Selection
Ec/No Channel Selection
Channel Reference and Channel Noise Power Reference Fields
When Ec/No is 0.0 dB, C/N is equal to the reference channel power. This is demonstrated in the following
C/N formula:
C/N = (Ec Ref Pow - Ec/No)
The total noise power in a 3.84 MHz bandwidth is calculated using the following formula:
Tp = 10 Log[(Cw + Nw) / .001]
Tp = total noise power (dBm)
Cw = linear carrier power (watts) across the 3.84 MHz bandwidth
Nw = linear noise power (watts) across the 3.84 MHz bandwidth
These formulas clearly show the relationship between Ec/No and C/N and their effect on the total noise
power across the 3.84 MHz bandwidth.
Chapter 17
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W-CDMA Downlink Concepts
Special Power Control Considerations When Using Compressed Mode
When using the compressed mode, more than a single power level is required. In addition to the rapidly
varying power levels for the DPCH, there are also periods of discontinuous transmission (gaps where no RF
is transmitted). This is why the signal generator turns off the ALC when the compressed mode is turned on.
Because the ALC is turned off, the output power level may not be consistent with the power level entered on
the ESG, so a manual power search must be performed in order to ensure the correct output power level.
Pressing the Do Power Search softkey executes the manual power search function. This is demonstrated in the
task “Performing a Manual Power Search” on page 629.
Temperature changes or changes to certain signal generator settings may cause the output power level to
change over time. It is recommended that you perform a manual power search at least every hour to maintain
the correct output power level.
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Chapter 17
W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
W-CDMA Frame Structures
W-CDMA Frame Structures
This section contains graphical representations of W-CDMA frame structures, with associated tables, for
downlink channels.
Downlink PICH Frame Structure
Figure 17-37
Chapter 17
PICH Frame Structure
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W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
W-CDMA Frame Structures
Downlink PCCPCH + SCH Frame Structure
Figure 17-38
PCCPCH + SCH Frame Structure
Table 17-7
Lengths of PCCPCH + SCH Fields
Parameter
Symbols Per Slot
Ndata
9
NSCHa
1
a. SCH comprises PSCH and SSCH
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Chapter 17
W-CDMA Downlink Digital Modulation for Receiver Test (Option 400)
W-CDMA Frame Structures
Downlink DPCCH/DPDCH Frame Structure
Figure 17-39
DPCCH/DPDCH Frame Structure
Table 17-8
DPDCH and DPCCH Fields
15
7.5
512
15
7.5
512
30
15
30
Bits/Slot
DPDCH Bits/Slot
TOTAL
DPCCH
DPDCH
Spread Factor
Channel Symbol
Rate (Ksps)
Channel Bit
Rate (Kbps)
Bits/Frame
Ndata1
DPCCH
Bits/Slot
Ndata2
NTFCI
NTPC
Npilot
90
150
10
0
4
0
2
4
30
120
150
10
0
2
2
2
4
256
240
60
300
20
2
14
0
2
2a
15
256
210
90
300
20
2
12
2
2
2a
30
15
256
210
90
300
20
2
12
0
2
4a
30
15
256
180
120
300
20
2
10
2
2
4a
30
15
256
150
150
300
20
2
8
0
2
8a
30
15
256
120
180
300
20
2
6
2
2
8a
Chapter 17
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W-CDMA Frame Structures
Table 17-8
DPDCH and DPCCH Fields (Continued)
30
128
510
90
600
40
6
28
0
2
4a
60
30
128
480
120
600
40
6
26
2
2
4a
60
30
128
450
150
600
40
6
24
0
2
8a
60
30
128
420
180
600
40
6
22
2
2
8a
120
60
64
900
300
1200
80
12
48
8b
4
8
240
120
32
2100
300
2400
160
28
112
8b
4
8
480
240
16
4320
480
4800
320
56
232
8b
8
16
960
480
8
9120
480
9600
640
120
488
8b
8
16
192
0
960
4
1872
0
480
19200
1280
248
1000
8b
8
16
TOTAL
Bits/Slot
60
Channel Bit
Rate (Kbps)
DPCCH
DPCCH
Bits/Slot
DPDCH
DPDCH Bits/Slot
Spread Factor
Channel Symbol
Rate (Ksps)
Bits/Frame
Ndata1
Ndata2
NTFCI
NTPC
Npilot
a. The number of pilot bits can vary with channel symbol rates of 15 and 30 ksps.
b. If TFCI bits are not used, then DTX (discontinuous transmission) is used in the TFCI field.
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Chapter 17
18 Troubleshooting
If the signal generator is not operating properly, refer to the proper section in this chapter for a possible
solution. If you do not find a solution, refer to the E4428C/38C ESG Signal Generators Service Guide.
NOTE
If the signal generator displays errors, always read the error message text by pressing
Utility > Error Info.
The following list shows the topics covered by this chapter:
•
“Basic Signal Generator Operations” on page 656
•
“Signal Generator Lock-Up” on page 664
•
“Error Messages” on page 666
•
“Upgrading Firmware” on page 669
•
“Returning a Signal Generator to Agilent Technologies” on page 670
•
“Contacting Agilent Sales and Service Offices” on page 671
655
Troubleshooting
Basic Signal Generator Operations
Basic Signal Generator Operations
Cannot Turn Off Help Mode
1. Press Utility > Instrument Info/Help Mode
2. Press the Help Mode Single Cont softkey until Single is highlighted.
The signal generator has two help modes; single and continuous.
When you press Help in single mode (the factory preset condition), help text is provided for the next key you
press. Pressing another key will exit the help mode and activate the key’s function.
When you press Help in continuous mode, help text is provided for the next key you press and that key’s
function is also activated (except for Preset). You will stay in help mode until you press Help again or change
to single mode.
No RF Output
Check the RF ON/OFF annunciator on the display. If it reads RF OFF, press RF On/Off to toggle the RF
output on.
The Power Supply has Shut Down
If the power supply is not working, it requires repair or replacement. There is no user-replaceable power
supply fuse. Refer to the E4428C/38C ESG Signal Generators Service Guide for instructions.
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Chapter 18
Troubleshooting
Basic Signal Generator Operations
Signal Loss While Working with Mixers
If you experience signal loss at the signal generator’s RF output during low-amplitude coupled operation
with a mixer, you can solve the problem by adding attenuation and increasing the RF output amplitude of the
signal generator.
Figure 18-1 on page 657 shows a hypothetical configuration in which the signal generator provides a low
amplitude signal to a mixer.
Figure 18-1
Effects of Reverse Power on ALC
SIGNAL GENERATOR
OUTPUT CONTROL
ALC LEVEL
= - 8 dBm
RF OUTPUT
= - 8 dBm
MIXER
RF LEVEL
CONTROL
DETECTOR
MEASURES
- 8 dBm
ALC LEVEL
LO
DETECTOR
MEASURES
- 5 dBm
REVERSE
POWER
LO FEEDTHRU
= - 5 dBm
LO LEVEL
= +10 dBm
IF
The internally leveled signal generator RF output (and ALC level) is −8 dBm. The mixer is driven with an
LO of +10 dBm and has an LO-to-RF isolation of 15 dB. The resulting LO feedthrough of −5 dBm enters
the signal generator’s RF output connector and arrives at the internal detector.
Depending on frequency, it is possible for most of this LO feedthrough energy to enter the detector. Since
the detector responds to its total input power regardless of frequency, this excess energy causes the ALC to
reduce the RF output of the signal generator. In this example, the reverse power across the detector is
actually greater than the ALC level, which may result in loss of signal at the RF output.
Figure 18-2 on page 658 shows a similar configuration with the addition of a 10 dB attenuator connected
between the RF output of the signal generator and the input of the mixer. The signal generator’s ALC level is
increased to +2 dBm and transmitted through a 10 dB attenuator to achieve the required −8 dBm amplitude
at the mixer input.
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Figure 18-2
Reverse Power Solution
SIGNAL GENERATOR
OUTPUT CONTROL
ALC LEVEL/
RF OUTPUT
= +2 dBm
RF INPUT
= - 8 dBm
10 dB
ATTEN
RF LEVEL
CONTROL
DETECTOR
MEASURES
+2 dBm
ALC LEVEL
MIXER
DETECTOR
MEASURES
- 15 dBm
REVERSE
POWER
LO
LO LEVEL
= +10 dBm
LO FEEDTHRU
= - 5 dBm
IF
Compared to the original configuration, the ALC level is 10 dB higher while the attenuator reduces the LO
feedthrough (and the RF output of the signal generator) by 10 dB. Using the attenuated configuration, the
detector is exposed to a +2 dBm desired signal versus the −15 dBm undesired LO feedthrough. This 17 dB
difference between desired and undesired energy results in a maximum 0.1 dB shift in the signal generator’s
RF output level.
Signal Loss While Working with Spectrum Analyzers
The effects of reverse power can cause problems with the signal generator’s RF output when the signal
generator is used with a spectrum analyzer that does not have preselection capability.
Some spectrum analyzers have as much as +5 dBm LO feedthrough at their RF input port at some
frequencies. If the frequency difference between the LO feedthrough and the RF carrier is less than the ALC
bandwidth, the LO’s reverse power can cause amplitude modulation of the signal generator’s RF output. The
rate of the undesired AM equals the difference in frequency between the spectrum analyzer’s LO
feedthrough and the RF carrier of the signal generator.
Reverse power problems can be solved by using one of two unleveled operating modes: ALC off or power
search.
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Basic Signal Generator Operations
ALC Off Mode
ALC off mode deactivates the automatic leveling circuitry prior to the signal generator’s RF output. In this
mode, a power meter is required to measure the output of the signal generator and assist in achieving the
required output power at the point of detection.
To set the signal generator to the ALC off mode, follow these steps:
1. Press Preset.
2. Press Frequency, enter the required frequency, and terminate the entry with the appropriate terminator
softkey.
3. Press Amplitude, enter the required amplitude, and terminate the entry with the appropriate terminator
softkey.
4. Set RF On/Off to Off.
5. Press Amplitude > ALC Off On to Off.
This deactivates the signal generator’s automatic leveling control.
6. Monitor the RF output amplitude as measured by the power meter.
7. Press Amplitude and adjust the signal generator’s RF output amplitude until the desired power is
measured by the power meter.
Power Search Mode
Power search mode executes a power search routine that temporarily activates the ALC, calibrates the power
of the current RF output, and then disconnects the ALC circuitry.
To set the signal generator to manual fixed power search mode, follow these steps:
1. Press Preset.
2. Press Frequency, enter the required frequency, and terminate the entry with the appropriate terminator
softkey.
3. Press Amplitude, enter the required amplitude, and terminate the entry with the appropriate terminator
softkey.
4. Set ALC Off On to Off
This deactivates the ALC circuitry.
5. Set RF On/Off to On.
6. Press Do Power Search.
This executes the manual fixed power search routine, which is the default mode.
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There are three power search modes: manual, automatic, and span.
When Power Search is set to Manual, pressing Do Power Search executes the power search calibration routine
for the current RF frequency and amplitude. In this mode, if there is a change in RF frequency or amplitude,
you will need to press Do Power Search again.
When Power Search is set to Auto, the calibration routine is executed whenever the frequency or amplitude of
the RF output is changed.
When Power Search is set to Span, pressing Do Power Search executes the power search calibration routine
over a selected range of frequencies at one time. The power search corrections are then stored and used
whenever the signal generator is tuned within the selected range of frequencies.
RF Output Power too Low
1. Look for an OFFS or REF indicator in the AMPLITUDE area of the display.
OFFS tells you that an amplitude offset has been set. An amplitude offset changes the value shown in the
AMPLITUDE area of the display but does not affect the output power. The amplitude displayed is equal to
the current power output by the signal generator hardware plus the value for the offset.
To eliminate the offset, press the following keys:
Amplitude > More (1 of 2) > Ampl Offset > 0 > dB.
REF tells you that the amplitude reference mode is activated. When this mode is on, the displayed
amplitude value is not the output power level. It is the current power output by the signal generator
hardware minus the reference value set by the Ampl Ref Set softkey.
To exit the reference mode, follow these steps:
a. Press Amplitude > More (1 of 2).
b. Press Ampl Ref Off On until Off is highlighted.
You can then reset the output power to the desired level.
2. If you are using the signal generator with an external mixer, see “Signal Loss While Working with
Mixers” on page 657.
3. If you are using the signal generator with a spectrum analyzer, see “Signal Loss While Working with
Spectrum Analyzers” on page 658.
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Basic Signal Generator Operations
No Modulation at the RF Output
Check the MOD ON/OFF annunciator on the display. If it reads MOD OFF, press Mod On/Off to toggle the
modulation on.
Although you can set up and enable various modulations, the RF carrier is modulated only when you have
also set Mod On/Off to On.
On the E4438C for digital modulation, make sure that I/Q Off On is set to On.
Sweep Appears to be Stalled
The current status of the sweep is indicated as a shaded rectangle in the progress bar. You can observe the
progress bar to determine if the sweep is progressing. If the sweep appears to have stalled, check the
following:
❏ Have you turned on the sweep by pressing any of the following key sequences?
Sweep/List > Sweep > Freq
Sweep/List > Sweep > Ampl
Sweep/List > Sweep > Freq & Ampl
❏ Is the sweep in continuous mode? If the sweep is in single mode, be sure that you have pressed the
Single Sweep softkey at least once since completion of the prior sweep. Try setting the mode to
continuous to determine if the missing single sweep is blocking the sweep.
❏ Is the signal generator receiving the appropriate sweep trigger? Try setting the Sweep Trigger softkey to
Free Run to determine if a missing sweep trigger is blocking the sweep.
❏ Is the signal generator receiving the appropriate point trigger? Try setting the Point Trigger softey to Free
Run to determine if a missing point trigger is blocking the sweep.
❏ Is the dwell time appropriate? Try setting the dwell time to one second to determine if the dwell time was
set to a value which was too slow or too fast for you to see.
❏ Do you have at least two points in your step sweep or list sweep?
Cannot Turn Off Sweep Mode
Press Sweep/List > Sweep > Off.
In the sweep mode menu you can choose to set the sweep to various sweep types or to turn sweep off.
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Troubleshooting
Basic Signal Generator Operations
Incorrect List Sweep Dwell Time
If the signal generator does not dwell for the correct period of time at each sweep list point, follow these
steps:
1. Press Sweep/List > Configure List Sweep.
This displays the sweep list values.
2. Check the sweep list dwell values for accuracy.
3. Edit the dwell values if they are incorrect.
NOTE
The effective dwell time at the RF OUTPUT connector is the sum of the value set for the
dwell plus processing time, switching time, and settling time. This additional time added to
the dwell is generally a few milliseconds. The TTL/CMOS output available at the
TRIG OUT connector, however, is asserted high only during the actual dwell time.
If the list dwell values are correct, continue to the next step.
4. Observe if the Dwell Type List Step softkey is set to Step.
When Step is selected, the signal generator will sweep the list points using the dwell time set for step
sweep rather than the sweep list dwell values.
To view the step sweep dwell time, follow these steps:
a. Press Configure Step Sweep.
b. Observe the value set for the Step Dwell softkey.
List Sweep Information is Missing from a Recalled Register
List sweep information is not stored as part of the instrument state in an instrument state register. Only the
current list sweep is available to the signal generator. List sweep data can be stored in the instrument catalog.
For instructions, see “Storing Files” on page 69.
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Basic Signal Generator Operations
Data Storage
Registers With Previously Stored Instrument States are Empty
The save/recall registers are backed-up by a battery when line power to the signal generator is not
connected. The battery may need to be replaced.
To verify that the battery has failed, follow these steps:
1. Turn off line power to the signal generator.
2. Unplug the signal generator from line power.
3. Plug in the signal generator.
4. Turn on the signal generator.
5. Observe the display for error messages.
If either error message −311 or −700 is stored in the error message queue, the signal generator’s battery
has failed.
6. Refer to the E4428C/38C ESG Signal Generators Service Guide for battery replacement instructions.
Saved an Instrument State in a Register but the Register is Empty or Contains the Wrong State
If you have selected a register number that is greater than 99, the signal generator will automatically select
register 99 to save your instrument state.
If the register number you intended to use is empty or contains the wrong instrument state, press the
following keys:
Recall > 99 > Enter.
This recalls register 99. The lost instrument state may be saved there.
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Troubleshooting
Signal Generator Lock-Up
Signal Generator Lock-Up
If the signal generator is locked up, check the following:
•
Make sure that the signal generator is not in remote mode. (In remote mode, the R annunciator will
appear on the display.) Press Local to exit remote mode and unlock the front panel keypad.
•
Make sure that the signal generator is not in local lockout condition. Local lockout will prevent front
panel operation of the signal generator. For more information on local lockout, refer to the E4428C/38C
ESG Signal Generators Programming Guide.
•
Check for a progress bar on the signal generator display which indicates that an operation is in progress.
•
Press Preset.
•
Cycle power on the signal generator.
Fail-Safe Recovery Sequence
The fail-safe recovery sequence should only be used if the previous suggestions do not resolve the problem.
NOTE
This process will reset the signal generator, but it will destroy data.
The fail-safe recovery sequence will destroy the following types of data:
•
all user files (instrument state and data files)
•
DCFM/DCΦM calibration data
•
persistent states
Do not attempt to perform any other front panel or remote operations during the fail-safe sequence.
To run the fail-safe sequence, follow these steps:
1. Hold down the Preset key while cycling power.
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Signal Generator Lock-Up
2. Continue to hold down the Preset key until the following message is displayed:
WARNING
You are entering the diagnostics menu which can cause unpredictable instrument
behavior. Are you sure you want to continue?
CAUTION
Carefully read the entire message! It may list additional risks with this procedure.
3. Release the Preset key.
4. Press Continue to continue with the sequence (or Abort to abort with no lost files).
At the conclusion of the sequence, follow these steps:
1. Cycle power.
Cycling power restores all previously installed options. You should expect to see several error messages
resulting from calibration files being restored from EEPROM.
2. Perform the DCFM/DCΦM calibration.
Refer to the DCFM/DCΦM Cal softkey description in the E4428C/38C ESG Signal Generators Key and
Data Field Reference Volume 1.
3. Agilent Technologies is interested in the circumstances that made it necessary for you to initiate this
procedure, please contact us using the website on page 670. We would like to help you eliminate any
repeat occurrences.
Chapter 18
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Troubleshooting
Error Messages
Error Messages
If an error condition occurs in the signal generator, it is reported to both the front panel display error queue
and the SCPI (remote interface) error queue. These two queues are viewed and managed separately; for
information on the SCPI error queue, refer to the E4428C/38C ESG Signal Generators Programming Guide.
NOTE
When there is an unviewed message in the front panel error queue, the ERR annunciator
appears on the signal generator’s display.
Characteristic
Front Panel Display Error Queue
Capacity (#errors)
30
Overflow Handling
Circular (rotating).
Drops oldest error as new error comes in.
Viewing Entries
Press: Utility > Error Info > View Next (or Previous) Error Page
Clearing the Queue
Press: Utility > Error Info > Clear Error Queue(s)
Unresolved Errorsa
Re-reported after queue is cleared.
No Errors
When the queue is empty (every error in the queue has been read, or the queue is cleared), the
following message appears in the queue:
0
No Error Message(s) in Queue
a. Errors that must be resolved. For example, unlock.
Error Message File
A complete list of error messages is provided in the file errormessages.pdf, on the CDROM supplied with
your instrument.
In the error message list, an explanation is generally included with each error to further clarify its meaning.
The error messages are listed numerically. In cases where there are multiple listings for the same error
number, the messages are in alphabetical order.
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Error Messages
Error Message Format
When accessing error messages through the front panel display error queue, the error numbers, messages
and descriptions are displayed on an enumerated (“1 of N”) basis.
Error messages appear in the lower-left corner of the display as they occur.
Explanation provided in the Error Message List
(This is not displayed on the instrument)
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Troubleshooting
Error Messages
Error Message Types
Events do not generate more than one type of error. For example, an event that generates a query error will
not generate a device-specific, execution, or command error.
Query Errors (–499 to –400) indicate that the instrument’s output queue control has detected a problem
with the message exchange protocol described in IEEE 488.2, Chapter 6. Errors in this class set the query
error bit (bit 2) in the event status register (IEEE 488.2, section 11.5.1). These errors correspond to message
exchange protocol errors described in IEEE 488.2, 6.5. In this case:
•
Either an attempt is being made to read data from the output queue when no output is either present or
pending, or
•
data in the output queue has been lost.
Device Specific Errors (–399 to –300, 201 to 703, and 800 to 810) indicate that a device operation did not
properly complete, possibly due to an abnormal hardware or firmware condition. These codes are also used
for self-test response errors. Errors in this class set the device-specific error bit (bit 3) in the event status
register (IEEE 488.2, section 11.5.1).
The <error_message> string for a positive error is not defined by SCPI. A positive error indicates that the
instrument detected an error within the GPIB system, within the instrument’s firmware or hardware, during
the transfer of block data, or during calibration.
Execution Errors (–299 to –200) indicate that an error has been detected by the instrument’s execution
control block. Errors in this class set the execution error bit (bit 4) in the event status register (IEEE 488.2,
section 11.5.1). In this case:
•
Either a <PROGRAM DATA> element following a header was evaluated by the device as outside of its
legal input range or is otherwise inconsistent with the device’s capabilities, or
•
a valid program message could not be properly executed due to some device condition.
Execution errors are reported after rounding and expression evaluation operations are completed. Rounding
a numeric data element, for example, is not reported as an execution error.
Command Errors (–199 to –100) indicate that the instrument’s parser detected an IEEE 488.2 syntax error.
Errors in this class set the command error bit (bit 5) in the event status register (IEEE 488.2, section 11.5.1).
In this case:
•
Either an IEEE 488.2 syntax error has been detected by the parser (a control-to-device message was
received that is in violation of the IEEE 488.2 standard. Possible violations include a data element that
violates device listening formats or whose type is unacceptable to the device.), or
•
an unrecognized header was received. These include incorrect device-specific headers and incorrect or
unimplemented IEEE 488.2 common commands.
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Upgrading Firmware
Upgrading Firmware
The firmware in your signal generator may be upgraded when new firmware is released. New firmware
releases may contain signal generator features and functionality not available in previous firmware releases.
To inquire about the availability of new signal generator firmware, contact Agilent at
http://www.agilent.com/find/upgradeassistant, or call 1 800 452 4844.
Chapter 18
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Troubleshooting
Returning a Signal Generator to Agilent Technologies
Returning a Signal Generator to Agilent Technologies
To return your signal generator to Agilent Technologies for servicing, follow these steps:
1. Gather as much information as possible regarding the signal generator’s problem.
2. Call the phone number listed on the Internet (http://www.agilent.com/find/assist) that is specific to your
geographic location. If you do not have access to the Internet, contact your Agilent field engineer.
After sharing information regarding the signal generator and its condition, you will receive information
regarding where to ship your signal generator for repair.
3. Ship the signal generator in the original factory packaging materials, if available, or use similar
packaging to properly protect the signal generator.
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Contacting Agilent Sales and Service Offices
Contacting Agilent Sales and Service Offices
Assistance with test and measurements needs and information on finding a local Agilent office are available
on the Internet at:
http://www.agilent.com/find/assist
You can also purchase E4428C/38C ESG accessories or documentation items on the Internet at:
http://www.agilent.com/find/esg
If you do not have access to the Internet, please contact your field engineer.
NOTE
Chapter 18
In any correspondence or telephone conversation, refer to the signal generator by its model
number and full serial number. With this information, the Agilent representative can
determine whether your unit is still within its warranty period.
671
Troubleshooting
Contacting Agilent Sales and Service Offices
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Chapter 18
Index
Symbols
ΦM
annunciator, 13, 34
configuring, 214
deviation, 214
rate, 214
Numerics
007, option, 5, 24
10 MHz IN connector, 18, 45
10 MHz OUT connector, 18, 46
2.1 MHz I/Q mod filter, 115
2’s complement description, 241, 254
321.4 IN connector, 38
40 MHz I/Q mod filter, 115
50-pack
licensing, 197
5-pack
history, waveform files, 200
licensing, 195, 197
601/602, option
description, 24
A
AC power receptacle, 17, 43
ACP, 91
activating a signal, 58
active entry area, 15, 36
adding & editing (instrument state), 71
alc
hold, 120–123
description, 126
saving settings, 125
power search, 659
ALC OFF annunciator, 13, 34
ALT PWR IN connector pin, 41
option 401, 339
AM
annunciator, 13, 34
depth, 211
modulation, 211
rate, 211, 212
wideband input connector, 32
wideband procedure, 212
Index
amplitude
display area, 15, 36
hardkey, 7, 27
LF output, 217, 218
modulation. See AM
power search, 659
amplitude offset, 52
amplitude reference, 52
amplitude sensitivity search, 284
analog modulation, 5, 24, 209
configuring, 210
annunciators, display area, 13–14, 34–36
ARB, 91
triggers, 140
waveform clipping, 149–156
waveform scaling, 157–160
ARMED annunciator, 13, 34
arrow keys, 10, 30
ATTEN HOLD annunciator, 13, 34
Auto, I/Q mod filter, 115
AUTOGEN_WAVEFORM file, 91, 93, 107
AUX I/O connector, 41
AWGN
dual ARB player, 112
B
baseband
clipping, 149–156
scaling, 157–160
BASEBAND GEN REF IN connector, 46
baseband generator, 91
custom arb mode, 24
custom real-time I/Q mode, 25
dual arb mode, 25
multitone mode, 25
options, 21
basic operation, 47–88
BBG DAC annunciator, 35
BCH synchronization, 279
BER connectors
BER CLK IN, 38
BER DATA IN, 38
BER GATE IN, 38
BER ERR OUT connector pin, 42
BER MEAS END connector pin, 42
673
Index
BER MEAS TRIG/BER NO DATA connector pin,
42
BER SYNC LOSS connector pin, 42
BER TEST OUT connector pin, 42
BER, DPCH transport channel, 519
BERT annunciator, 34
BERT, option UN7, 268
GPS, 368
GPS testing, 373
loopback test equipment setup, 273
bit file editor, using, 190
bits per symbol, equation, 175
block diagrams
frame structure
DPCCH/DPDCH downlink, 452, 653
DPCCH/DPDCH uplink, 454, 587
PCCPCH+SCH, 451, 652
PICH, 450, 651
GPS signal generation, 364
GPS subframe structures, 365
MSGPS signal generation, 357
Bluetooth marker behavior, 123
Bluetooth signal, setting up, 258
BURST GATE IN connector, 45
C
calibration, 4, 23
carrier bandwidth, 112
carrier signal modulation, 60
carrier to noise ratio, 112
catalog, FIR files, 347
CCDF curve, 154–156
CDMA template, customizing, 350
cdma2000
component test, storing, 320, 321
forward link modulation, 312, 326
I/O timing relationships
forward link, 341
reverse link, 343
reverse link modulation, 316, 332
cdma2000, receiver test
forward link
adjusting code domain power, 328
base station setup, 326
changing channel states, 326, 327
674
configuring the RF output, 331
generating the baseband signal, 330
modifying channel parameters, 327
scaling to 0 dB, 328
setting EbNo, 330
setting equal channel powers, 329
setting noise parameters, 329
setting the carrier to noise ratio, 330
timing relationships, 341, 342
reverse link
adjusting code domain power, 334
changing channel states, 333
changing the operating mode, 332
configuring the RF output, 337
editing channel setups, 332
generating the baseband signal, 336
mobile setup, 332
modifying channel parameters, 333
scaling to 0 dB, 334
setting EbNo, 336
setting equal channel powers, 335
setting noise parameters, 335
setting the carrier to noise ratio, 336
timing relationships, 341, 342
ceiling function, bits per symbol, 175
certificate, license key, 84
channels
forward link, editing, 313, 317
PCCPCH+SCH, 451, 652
circular clipping, 155
clipping
CCDF curve, 154–156
circular, 152, 155
concepts, 149–154
procedure, 155, 156
rectangular, 152, 156
clock adjustment
phase and skew, 232
clock gate, 292
clock rate limits, logic type output, 220
clock source
setting, 244, 251
clock timing
parallel data, 227
parallel interleaved data, 230
Index
Index
phase and skew, 232
serial data, 232
clocking, frequency reference, 224
clocking, frequency reference diagrams, 226
clocks per sample
parallel data, 227
parallel interleaved data, 230
coefficient values, entering, 169
COH CARRIER connector, 39
comments, adding & editing (instrument state), 71
common frequency reference diagrams, 226
component test, 91
components, testing, 311, 424, 436
compressed mode, W-CDMA
downlink, 619
frame structure, 621
manual power search, 629, 650
uplink
manual power search, 582
multiple TGPS, 540
single TGPS, 529
concepts
waveform clipping, 149–154
waveform markers, 125
waveform scaling, 157–159
confidential data, 75
connection diagram
user flatness correction, 63
connections
common frequency reference, 226
connectors, 338
10 MHz IN, 18, 45
10 MHz OUT, 18, 46
321.4 IN, 38
ALT PWR IN, 41
ALT PWR IN, option 401, 339
AUX I/O, 41
BASEBAND GEN REF IN, 46
BER CLK IN, 38
BER DATA IN, 38
BER ERR OUT, 42
BER GATE IN, 38
BER MEAS END, 42
BER MEAS TRIG/BER NO DATA, 42
BER SYNC LOSS, 42
Index
BER TEST OUT, 42
BURST GATE IN, 45
COH CARRIER, 39
DATA, 32
option 401, 338
DATA CLK OUT, 41
DATA CLK OUT, option 401, 340
DATA CLOCK, 31
option 401, 338
DATA OUT, 41, 339
DATA OUT, option 401, 339
digital bus, 43
EVENT 1, 40
option 401, 340
EVENT 2, 40, 340
option 401, 340
EVENT 3, 42
EVENT 4, 42
EXT 1 INPUT, 8, 28
EXT 2 INPUT, 8, 28
external triggering, 143
external triggering source, 145
front panel inputs, cdma2000, 338
GPIB, 17, 44
I, 32, 212
I OUT, 39
I-bar OUT, 38
LAN, 18, 44
LF OUTPUT, 8, 29
PATT TRIG IN, 41
PATT TRIG IN 2, 42
PATTERN TRIG IN, option 401, 339
Q, 32
Q OUT, 39
Q-bar OUT, 40
rear panel inputs, cdma2000, 339
rear panel outputs, cdma2000, 339
RF OUTPUT, 9, 29
RS 232, 17, 44
SWEEP OUT, 18, 45
SYM SYNC OUT, 42
option 401, 340
SYMBOL SYNC, 31
TRIG IN, 18, 45
TRIG OUT, 18, 45
675
Index
continuous
triggering, 142
continuous step sweep example, 55
continuous wave
description, 5, 24
output, 50
contrast hardkeys, 10, 30
control part power, message part, 466
control timeslot ramping
GSM, 399
GSM & EDGE, 396
correction array (user flatness)
configuration, 63
load from step array, 64
viewing, 64
See also user flatness correction
creating waveform segments, 108
creating waveform sequences, 109
custom
CDMA template, editing, 350
cdma2000 waveforms
creating, 322
storing, 320, 321
using, 324
multicarrier CDMA waveforms
creating, 352
editing, 354
multicarrier TDMA waveforms
creating, 387
RF output, configuring, 392
TDMA digital modulation, 384
custom arb, 92
custom arb waveform generator, 24
custom mode, 91
custom real-time I/Q baseband, 25
CW mode
description, 5, 24
D
DAC over-range errors, 157–159
data
framed, 141
input methods, 75
patterns
triggering, 140
676
removal, 78
sensitive, 75, 78
storage, 75
unframed, 141
DATA CLK OUT connector pin, 41
option 401, 340
DATA CLOCK connector, 31, 338
DATA connector, 32, 338
data fields
editing, 49
data files
creating, 190
modifying, 193
data filtering, pre or post fir, 241, 254
DATA OUT connector pin, 41
option 401, 339
data part power, message part, 467
data processing, 299
data storage
file types, 68
troubleshooting, 663
data types, 236
declassification, 75
DECT framed modulation, 413
default navigation data, GPS, 365
default waveform file, 93
delay, external trigger signal, 142
Delete Item softkey, 49
Delete Row softkey, 49
description, adding & editing (instrument state), 71
device clock source selection, 244, 251
DHCP, 85
diagram
data types, 236
diagrams
clock timing
parallel data, 227
parallel interleaved data, 230
phase and skew, 232
serial data, 232
common frequency reference, 226
differential encoding, bits per symbol, 175
differential state map, bits per symbol, 175
digital bus, 43
digital modulation
Index
Index
annunciators, 36
component testing, 311, 424, 436
formats, 24
IQ map, QAM, 176
receiver testing, 393
TDMA, 384
W-CDMA, 423–454, 589–653
digital signal interface module
N5102A, 219
discrete steps, skew range, 232
display
active entry area, 15, 36
amplitude area, 15, 36
annunciators, 13, 14, 34, 36
blanking, 82
contrast hardkeys, 10, 30
description, 12, 33
error message area, 15, 36
secure, 82
softkey area, 15, 36
text area, 15, 36
documentation map, xxiii
downlink
DPCCH frame structure, 452, 653
DPCH slot formats A and B, 621
DPDCH frame structure, 452, 653
PCCPCH+SCH frame structure, 451, 652
PICH frame structure, 450, 651
scramble codes, 446
downlink errors, 304
downloading firmware, 3, 22
DPCCH
downlink frame structure, 452, 653
uplink frame structure, 454, 587
DPCH slot formats A and B, 621
DPCH, transport channel BER, 519
DPCH, uplink, TPC equipment setup, 525
DPDCH
downlink frame structure, 452, 653
uplink frame structure, 454, 587
dual ARB, 91, 101
dual ARB player, 25, 107–114
dual ARB real time noise, 112
dual arbitrary waveform generator, 25, 107–114
Index
E
EDGE
frame structure, 305
framed modulation, 394
framed modulation with GMSK, 394
timeslot ramping control, 396
Edit Item softkey, 49
editing file headers, 95, 101
editor, bit file, 190
equipment setup
DPCH and PRACH, 459, 564
DPCH, uplink, TPC, 525
multiple PRACH overload test, 509
PRACH AICH, 482, 484
user flatness correction, 63
equipment, user flatness correction, 61
Erase All, 79, 80, 81, 82
erase and overwrite, 79
erase and sanitize, 80
erased frame detection, 304
erasing memory, 75, 79, 80, 81, 82
ERR annunciator, 13, 34, 666
error messages
DAC over-range, 157–159
display area, 15, 36
message format, 667
overview, 666
queue, 666
types, 668
ESG
configuring GSM, 276
modes of operation, 5, 24
EVENT 1 connector, 40
option 401, 340
EVENT 2 connector, 40
option 401, 340
EVENT 3 connector pin, 42
EVENT 4 connector pin, 42
examples
ΦM, configuring, 214
AM, configuring, 211
continuous wave output, 50
custom cdma2000 state, storing, 320, 321
files
storing, 69
677
Index
viewing, 68
FIR filters
creating, 168
modifying, 173
using, 347
FM, configuring, 213
LF output, configuring, 216
options, enabling, 84
pulse modulation, configuring, 215
RF output, configuring, 50–57
swept output, 53
table editor, list mode values, 48
table editors, editing, 49
traffic channels, inserting, 315, 318
user flatness correction, 61–67
EXT 1 INPUT connector, 8, 28
EXT 2 INPUT connector, 8, 28
EXT REF annunciator, 13, 34
EXT1 annunciators, 13, 34
EXT2 annunciators, 13, 34
external clock source selection, 244, 251
external modulation, 212
external trigger
connection, 143
gated, setting, 143
source connector, 145
F
fail-safe recovery sequence, 664
features, signal generator, 2, 20
file header description, 96
file headers
dual ARB, 101, 102
editing, 95, 101
generating, 101
overview, 93
playing waveforms, 105
sequences, 101
settings, 93
viewing, 101
viewing a different file, 103
files, 70
FIR filter, using, 347
FSK, storing, 188
using, 68
678
waveform segments, 108, 113
waveform sequences, 109–112
See also instrument state register
See also memory catalog
filtered & unfiltered samples, 241, 254
filters
gaussian, loading default, 173
I/Q mod, 115, 117
interpolation, 157–159
nyquist, selecting, 385
FIR filters
creating, 168
custom filter, using, 347
modifying, 173
storing, 172
FIR table editor
accessing, 168
coefficients, duplicating, 169
coefficients, entering values, 169
coefficients, modifying, 174
files, loading, 173
filters
creating, 168
modifying, 173
storing, 172, 174
oversample ratio, setting, 170
firmware
upgrades
obtaining, 3, 22
using GPIB, 3, 22
using LAN, 3, 22
using RS-232, 3, 22
firmware, upgrading, 669
flatness correction. See user flatness correction
FM
annunciator, 13, 34
configuration example, 213
deviation, 213
rate, 213
format, generating, 58
formula, skew discrete steps, 232
forward link modulation
cdma2000, 312
forward link modulation, cdma2000, 326
forward link traffic channels, inserting, 315, 318
Index
Index
frame structure, 304, 450
downlink
compressed mode, 621
DPCCH, 452, 653
DPDCH, 452, 653
PCCPCH+SCH, 451, 652
PICH, 450, 651
uplink
DPCCH, 454, 587
DPDCH, 454, 587
framed data, 141
framed modulation
DECT, 413
EDGE, 394
GSM, 398
NADC, 419
PDC, 417
PHS, 415
TETRA, 421
free run trigger response, 142
frequency
display area, 12, 33
hardkey, 7, 26
LF output, 217
start and stop, swept-sine, 218
modulation. See FM
offset, 51
reference, 51
RF output, setting, 50
frequency output limits, clock rates & logic levels,
220
frequency reference
common, 224
hookup diagrams, 226
front panel
disabling keys, 82
display description, 12, 33
features, 6, 16, 26, 37
knob, 7, 27
front panel connectors, 338
front panel inputs
description, cdma2000, 338
FSK files, storing, 188
fundamental operation See basic operation
Index
G
gated triggering, 141, 143
gaussian filter, loading default, 173
GMSK modulation, 394
Goto Row softkey, 49
GPIB
connector, 17, 44
listener mode, 66
GPS
BER testing, 368, 373
chip clock reference, 366
configuring external reference clock, 370
data modes, 365
default navigation data, 365
handover word, 365
overview, 363
satellite ID range, 363
sensitivity testing, 372
signal generation diagram, 364
subframe indicator, 366
subframe structures, 365
TLM word, 365
user files, 368
green LED, 10, 31
GSM
configuring the ESG, 276
configuring the VSA, 275
frame structure, 304
framed modulation, 398
timeslot ramping control, 396, 399
H
handover word, GPS, 365
hardkeys
Amplitude, 7, 27
arrow, 10, 30
contrast, 10, 30
Frequency, 7, 26
Help, 8, 28
Hold, 10, 30
Incr Set, 9, 30
Local, 10, 30
MENUS group, 7, 27
Mod On/Off, 9, 29
679
Index
numeric, 9, 29
Preset, 10, 30
Recall, 7, 27
Return, 10, 30
RF On/Off, 9, 29
Save, 7, 27
Trigger, 8, 28
header files, 93
Help hardkey, 8, 28
Hold hardkey, 10, 30
I
I connector, 32, 212
I OUT connector, 39
I/O
functionality, 338
signal descriptions, 338
option 401, 338, 339
timing relationships, 338
I/O signal descriptions
option 401, 339
I/O timing relationships
cdma2000, forward link, 341
cdma2000, reverse link, 343
I/Q mod filters, 115, 117
I/Q waveform
clipping, 149–156
scaling, 157–160
I-bar OUT connector, 38
Incr Set hardkey, 9, 30
input connectors, 38
10 MHz IN, 18, 45
321.4 IN, 38
AUX I/O, 41
BASEBAND GEN REF IN, 46
BER CLK IN, 38
BER GATE IN, 38
BURST GATE IN, 45
DATA, 32
DATA CLOCK, 31
EXT 2 INPUT, 8, 28
GPIB, 17, 44
I, 32, 212
LAN, 18, 44
line power, 17, 43
680
PATT TRIG IN, 41
Q, 32
RS 232, 17, 44
SYMBOL SYNC, 31
TRIG IN, 18, 45
Insert Item softkey, 49
Insert Row softkey, 49
installation guide, xxiii
installing firmware, 3, 22
instrument state register
comments, adding and editing, 71
troubleshooting, 663
using, 70
See also memory catalog
interface, remote
GPIB, returning to listener mode, 66
intermodulation distortion
how to minimize, 151
internal clock source selection, 244, 251
interpolation filter, 157–159
interslot ramping control, GSM, 399
interslot ramping control, GSM & EDGE, 396
IQ
clock rates, 222
IQ map, QAM modulation, 176
IS-95A modulation, 349
K
key, license, 84
keypad, numeric, 9, 29
keys
disabling, 82
knob, front panel, 7, 27
L
L (listener mode) annunciator, 13, 34
lan configuration, 85
LAN connector, 18, 44
LEDs, 10, 31
left alternate scramble code, 448
LF output
amplitude, 217, 218
configuration example, 217, 218
description, 216
Index
Index
frequency, 217
source
function generator, 218
internal modulation monitor, 217
swept-sine
start frequency, 218
stop frequency, 218
waveform, 210, 216, 218
LF OUTPUT connector, 8, 29
LFO. See LF output
license key, 84
licensing
waveforms, 195, 197
limits, clock & sample rates, logic outputs, 220
line power (green) LED, 10, 31
list mode values table editor example, 48
list sweep examples, 55–57
listener mode
annunciator, 13, 34
returning to, 66
Load/Store softkey, 49
loading seqments, 113
Local hardkey, 10, 30
logic type
output levels, 220
selecting, 239
loopback BER
measuring, 282
low frequency output. See LF output
M
manual power search
W-CDMA DL, 629
W-CDMA UL, 582
marker, Bluetooth behavior, 123
markers
waveform, 120–123, 124–139
measuring RF loopback BER, 273
media storage, 75
memory, 107
base instrument, 75
baseband generator, 75
erasing, 75, 79
hard disk, 75
overwriting, 79
Index
persistence, 75
physical location, 75
sanitizing, 80
secure mode, 81
size, 75
types, 75
waveform, 75
writing to, 75
memory catalog
troubleshooting, 663
using, 68
See also instrument state register
menu, hardkeys, 7, 27
menus
marker, 129
marker polarity, 139
trigger, 142
message part
control part power, 466
data part power, 467
scrambling code, 465
slot formats, 464
structure, 463
message part power examples, 470
message part power, PRACH, 470
mirror table, duplicating coefficients, 169
MOD ON/OFF annunciator, 14, 35
Mod On/Off hardkey, 9, 29, 60
mode, power search, 659
modes of operation, 5, 24
modes, triggering, 141
modify file header, 95
modulation
amplitude. See AM
analog, 5, 24, 209
configuring, 210
annunciators, 14, 35, 36
carrier signal, 60
component testing, 311, 424, 436
digital, 24
format generation, 58
forward link, cdma2000, 312
framed
DECT, 413
EDGE, 394
681
Index
GMSK, 394
GSM, 398
NADC, 419
PDC, 417
PHS, 415
TETRA, 421
frequency. See FM
IS-95A, 349
phase. See ΦM
pulse, 5, 24, 215
receiver testing, 393
reverse link, cdma2000, 316
modulator, I/Q mod filters, 115, 117
module user interface location, 238, 247
MSGPS
chip rate, 362
external reference clock, 362
generating a signal, 361
RF power level, 359
scenario files, 356, 358, 361
signal generation diagram, 357
multicarrier CDMA waveforms
creating, 352
editing, 354
multicarrier cdma2000 waveforms
creating, 322
using, 324
multicarrier TDMA waveforms
creating, 387
multitone, 91
multitone mode, 25
multitone waveform, setup, 378
N
N5102A
baseband data, 238
clock rates, 220
clock settings, 242, 249
clock source
description, 223
clock timing, 220, 227
common frequency reference, 224
connections to clock and device, 234
data parameters, setting, 240, 253
data types, 236
682
digital data, 255
digital signal interface module, 219
frequency reference connector, 225
generating data, 246
input direction, 248
input mode, 236, 247
interleaving clock timing, 230
logic type, port configuration, 248
logic types, 239
output direction, 240
output mode, 236, 238
phase and skew clock timing, 232
serial clock timing, 232
user interface, 238
user interface module, 247
NADC framed modulation, 419
negation description, 242, 255
noise, 112
noise bandwidth factor, 112
non-volatile memory, 107
numeric format selection, 241, 254
numeric keypad, 9, 29
NVWFM, 93, 107
nyquist filter, selecting, 385
O
off/on key usage, modulation format, 58
offset
amplitude, 52
frequency, 51
offset binary use, 241, 254
on/off switch, 11, 31
operation
basic, 47–88
modes of, 5, 24
options, 3, 21
007, 5, 24
221-229, 195, 197
250-259, 195, 197
409, GPS, 363
424, GPS, 363
424, MSGPS, 356
601/602
description, 24
baseband generator, 21
Index
Index
enabling, 84
UN7, BERT, 268, 373
UNT, 5, 24
UNU, 5, 24
UNW, 5, 24
out of synchronization testing, W-CDMA DL, 612
output connectors
10 MHz OUT, 18, 46
AUX I/O, 41
COH CARRIER, 39
EVENT 1, 40
EVENT 2, 40
GPIB, 17, 44
I OUT, 39
I-bar OUT, 38
LF OUTPUT, 8, 29
Q OUT, 39
Q-bar OUT, 40
RF OUTPUT, 9, 29
RS 232, 17, 44
SWEEP OUT, 18, 45
TRIG OUT, 18, 45
output levels, logic types, 220
output. See LF output and RF output
OVEN COLD annunciator, 14, 35
over-range errors, 157–159
overview, file headers, 93
overview, GPS, 363
overview, signal generator, 1–18, 19–46
overwriting memory, 79
P
Page Down softkey, 49
Page Up softkey, 49
parallel
clock rates, 222
data clock timing, 227
interleaved data clock timing, 230
sample rates, 222
PATT TRIG IN 2 connector pin, 42
PATT TRIG IN connector, 41
PATTERN TRIG IN connector, option 401, 339
PCCPCH+SCH
frame structure, 451, 652
PDC framed modulation, 417
Index
peak to average power
CCDF curve, 154
high ratios, 151
reducing, 152
phase clock timing, 232
phase modulation. See ΦM
PHS framed modulation, 415
PICH frame structure, 450, 651
pilot power offset, 444
player, dual ARB, 107–114
polarity
markers, 139
trigger, external, 143
port configuration, selecting, 239
power
offsets, 444
peaks, 149–154
search, 659
sensor, models, 61
switch, 11, 31
power adjustment, timeslots, 396, 399
power control modes, 471
Pp-m, 471
total, 472
power meter
configuration, 62
user flatness correction, 61
power receptacle, 17, 43
power supply, troubleshooting, 656
Pp-m power control mode, 471
PRACH
AICH equipment setup, 482, 484
equipment setup, 459
overload test equipment setup, 509
PRACH power control
message part, 470
control part power, 466
data part power, 467
data part power formulas, 468, 469
power formula, 470
preamble power, 466
PRAM, 91
preamble
power control, 466
scrambling codes, 463
683
Index
signature, 462
pre-fir samples selection, 241, 254
Preset hardkey, 10, 30
primary scramble code, 447
private data, 75
problems with security function, 82
programming guide, xxiii
proprietary data, 75
protecting data, 75
PSG
firmware, 3, 22
PULSE annunciator, 14, 35
pulse modulation, 5, 24
period, 215
width, 215
pulse, marker, viewing, 136
pulse/rf blank, 120–123
Q
Q connector, 32
Q OUT connector, 39
QAM modulation IQ map, 176
Q-bar OUT connector, 40
queue, error, 666
R
R (remote) annunciator, 14, 35
ramping timeslots
GSM, 399
GSM & EDGE, 396
real time, 91, 92
noise, 112
triggers, 140
real-time mode, 25
rear panel connectors, 339
rear panel input signals
description, cdma2000, 339
description, W-CDMA UL, 566
locating, W-CDMA DL, 637
locating, W-CDMA UL, 555
rear panel output signals
configuring, W-CDMA DL, 639
configuring, W-CDMA UL, 557
description, cdma2000, 339
684
description, W-CDMA DL, 641
description, W-CDMA UL, 566
recall, 70
Recall hardkey, 7, 27
recall states, 70
receiver test, 91
receiver testing, real time TDMA, 393
recovery sequence, fail-safe, 664
rectangular clipping, 156
reference
amplitude, 52
frequency, 51
GPS chip clock, 366
MSGPS chip clock, 362
references, xxiii
registers, 70, 74
remote control
GPIB, returning to listener mode, 66
remote operation annunciator, 14, 35
removing sensitive data, 78
repeat measurements, 300
required equipment
GPS BER test, 373
W-CDMA transmit diversity, 601, 613, 622
reset & run trigger response, 142
response, triggering mode, 141
restricted data, 75
Return hardkey, 10, 30
returning a signal generator, 670
reverse link modulation
cdma2000, 316, 332
RF blanking, 120–123
marker function, 137
settings, saving, 125
RF loopback BER measurement, 273
RF ON/OFF annunciator, 14, 35
RF On/Off hardkey, 9, 29
RF output
configuring, 50–57
connector, 9, 29
troubleshooting, 656
user flatness correction, 61–67
right alternate scramble code, 448
routing, marker, 126
RF blanking, 137
Index
Index
saving settings, 125
RS-232, 17, 44
runtime scaling, 159
dual ARB, 159
multitone, 160
S
S (service request) annunciator, 14, 35
sample
rates, 220
parallel/parallel intrlvd port configuration, 222
serial port configuration, 221
type selection, 241, 254
samples
baseband, 157–159
interpolated, 157–159
sanitizing memory, 80
satellite ID range, GPS, 363
save, 70
save and recall states, 70
Save hardkey, 7, 27
scaling
concepts, 157–159
procedure, 159, 160
dual ARB, 159
multitone, 160
runtime, 159
dual ARB, 159
multitone, 160
waveform data, 160
scenario files
MSGPS, 356, 358
downloading, 358
playing, 361
SCH, TSTD, 599
SCPI, 85
SCPI reference, xxiii
scramble codes
calculating, 646
downlink, calculating, 446
primary and secondary, 447
scrambling code, message part, 465
search, power, 659
secondary scramble code, 447
secure display, 82
Index
secure mode, 81
security functions, 75, 81
problems with, 82
security level, 81
segment advance triggering, 142, 145
segments, waveforms, 108, 113
sensitive data, 75
sensitivity testing, GPS, 372
sequence file headers, 101
sequences, 113
creating and storing, 109–112
deleting, 74
editing, 111
instrument state register, 70
marker control, 134
playing, 110
triggering, 140
serial
clock and sample rates, 221
clock timing, 232
service guide, xxiii
service request annunciator, 14, 35
service, Agilent sales and service offices, 671
settings, file headers, 93
signal generation, 58
signal generator
firmware, 3, 22
firmware, upgrading, 669
GPIB listener mode, returning to, 66
modes, 5, 24
operation, basic, 47–88
overview, 1–18, 19–46
standard features, 2, 20
signal generator lock up, 664
single step sweep example, 54
single trigger mode, 141
skew
clock timing, 232
range, 232
slot formats A and B, DPCH, 621
slot formats, message part, 464
softkeys
location
key, 6, 26
labels, 15, 36
685
Index
table editor, 49
source, external trigger, 143
special pattern ignore function, 300
spectral regrowth, 151
standard features, signal generator, 2, 20
standby (yellow) LED, 10, 31
step array (user flatness)
number of points configuration, 64
start and stop frequency configuration, 64
See also user flatness correction
step sweep, 53–55
storing segments, 113, 114
structure, PRACH message part, 463
STTD encoding, W-CDMA transmit diversity, 598
subframe indicator, GPS, 366
sweep
annunciator, 14, 35
mode, 5, 24
trigger, 57
troubleshooting, 661
SWEEP OUT connector, 18, 45
swept output examples, 53–57
switch, power, 11, 31
SYM SYNC OUT connector pin, 42
SYM SYNC OUT connector pin, option 401, 340
SYMBOL SYNC connector, 31
synchronization, 299, 300, 303
synchronizing
BCH, 279
TCH, 281
T
T (talker mode) annunciator, 14, 35
table editors
modifying, 49
softkeys, 49
using, 48
talker mode annunciator, 14, 35
TCH synchronization, 281
TCP/IP, 85
TDMA digital modulation, 384
TETRA framed modulation, 421
text area (on display), 15, 36
TFCI
power offset, 444
686
Through, I/Q mod filter, 115
timeslot power level adjustment, 396, 399
timeslot ramping control
GSM, 399
GSM & EDGE, 396
timing relationships
cdma2000 forward link, 341, 342
TLM word, GPS, 365
total power control mode, 472
TPC
DPCH uplink, 525, 585
equipment setup, DPCH uplink, 525
power offset, 444
values, 443
traffic channels, inserting, 315, 318
transmit diversity, W-CDMA
overview, 598
STTD encoding, 598
TSTD, 599
transmit power control, 443
transport channel DPCH BER setting, 519
TRIG IN connector, 18, 45
TRIG OUT connector, 18, 45
trigger
connectors, 18, 45
hardkey, 8, 28
setting, 57
trigger & run, 142
triggers, 140–146
troubleshooting
data storage, 663
fail-safe recovery sequence, 664
help mode, 656
RF output, 656–661
signal generator lock up, 664
sweep, 661–662
TSTD for SCH, 599
two tone, 91
U
unfiltered & filtered samples, 241, 254
unframed data, 141
UNLEVEL annunciator, 14, 35
UNLOCK annunciator, 14, 35
UNT, option, 5, 24
Index
Index
UNU, option, 5, 24
UNW, option, 5, 24
upgrading firmware, 3, 22
uplink
DPCCH frame structure, 454, 587
DPDCH frame structure, 454, 587
user
documentation, xxiii
user files
FIR files catalog, 347
GPS usage, 368
modifying, 193
user files, data, 190, 193
user flatness correction, 61–67
user interface location, module, 238, 247
V
volatile memory, 107
VSA
configuring GSM, 275
required options, 273
W
Walsh Code, editing CDMA template, 350
warranted logic output clock rates, 220
waveform
50-pack, 195
5-Pack, 195, 197
5-pack history, 200
licenses, 203
licensing, 195
memory, 75
waveforms
CCDF curve, 154–156
clipping, 149–156
DAC over-range errors, 157–159
interpolation, 157–159
markers, 120–123, 124
player, dual ARB, 107–114
samples, 157–159
scaling, 157–160
segments, 108, 113
sequences, 109–112, 134
statistics, 155–156
Index
triggering, 140
utilities, 155–156
waveform 5-pack, 200
W-CDMA digital modulation, 423–454, 589–653
W-CDMA, receiver test
downlink
adjusting code domain power, 593
applying settings to an active signal, 596
base station setup, 590
compressed mode, 619
configuring the physical layer, 591
configuring the RF output, 597
configuring the transport layer, 592
DPCH slot formats A and B, 621
frame structure, 450, 651
frame structure, compressed mode, 621
generating the baseband signal, 596
manual power search, 629
out-of-synchronization testing, 612
rear panel output signal descriptions, 641
rear panel output signals, configuring, 639
scaling to 0 dB, 593
setting EcNo, 595
setting equal channel powers, 594
setting noise parameters, 595
setting the carrier to noise ratio, 595
STTD encoding, 598
transmit diversity, 598
TSTD for SCH, 599
uplink
adjusting code domain power, 560
compressed mode, 529
configuring DPCCH/DPDCH, 516
configuring PRACH, 476
configuring user equipment, 554
manual power search, 582
modifying the physical layer, 476, 518
modifying the transport layer, 520
rear panel output signals, configuring, 557
rear panel signal descriptions, 566
scaling to 0 dB, 560
selecting a reference measurement channel, 516
setting DPCH transport channel BER, 519
setting EbNo, 524
setting equal channel powers, 561
687
Index
setting noise parameters, 522
setting the carrier to noise ratio, 522
setting up the compressed mode, 543, 622
web server, 85
WFM1, 93, 107
wideband AM, 212
input connector, 32
Y
yellow LED, 10, 31
688
Index
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