Comtech EF Data SDM-650B Specifications

Comtech EF Data SDM-650B Specifications
SDM-650B
Satellite Modem
Installation and Operation Manual
Part Number MN/SDM650B.IOM
Revision 5
EFData Corporation is an ISO 9001 Registered Company
SDM-650B
Satellite Modem
Installation and Operation Manual
Part Number MN/SDM650B.IOM
Revision 5
May 28, 1996
Special Instructions:
This is the sixth edition of the manual.
Change bars were not utilized.
This revision supersedes part number MN/SDM650 Rev. 4 dated May 5, 1995.
Copyright © EFData Corporation, 1995, 1996.
All rights reserved.
Printed in the USA.
EFData Corporation, 2105 West 5th Place, Tempe, Arizona 85281 USA, (602) 968-0447, FAX: (602) 921-9012.
Warranty Policy
This EFData Corporation product is warranted against defects in material and
workmanship for a period of one year from the date of shipment. During the warranty
period, EFData will, at its option, repair or replace products that prove to be defective.
For equipment under warranty, the customer is responsible for freight to EFData and
all related custom, taxes, tariffs, insurance, etc. EFData is responsible for the freight
charges only for return of the equipment from the factory to the customer. EFData will
return the equipment by the same method (i.e., Air, Express, Surface) as the
equipment was sent to EFData.
Limitations of Warranty
The foregoing warranty shall not apply to defects resulting from improper installation or
maintenance, abuse, unauthorized modification, or operation outside of environmental
specifications for the product, or, for damages that occur due to improper repackaging
of equipment for return to EFData.
No other warranty is expressed or implied. EFData Corporation specifically
disclaims the implied warranties of merchantability and fitness for particular
purpose.
Exclusive Remedies
The remedies provided herein are the buyer's sole and exclusive remedies. EFData
Corporation shall not be liable for any direct, indirect, special, incidental, or
consequential damages, whether based on contact, tort, or any other legal theory.
Disclaimer
EFData has reviewed this manual thoroughly in order that it will be an easy-to-use
guide to your equipment. All statements, technical information, and recommendations
in this manual and in any guides or related documents are believed reliable, but the
accuracy and completeness thereof are not guaranteed or warranted, and they are not
intended to be, nor should they be understood to be, representations or warranties
concerning the products described. Further, EFData reserves the right to make
changes in the specifications of the products described in this manual at any time
without notice and without obligation to notify any person of such changes.
If you have any questions regarding your equipment or the information in this manual,
please contact the EFData Customer Support Department. (For more information,
refer to the preface.)
Preface
About this Manual
This manual provides installation and operation information for the EFData SDM-650B
satellite modem.
This is a technical document intended for earth station engineers, technicians, and
operators responsible for the operation and maintenance of the SDM-650B satellite
modem.
Organization
This manual includes the following chapters and appendixes:
Rev. 5
•
Chapter 1 — describes the unit’s purpose, function, description, options, and
system specification.
•
Chapter 2 — describes the unit’s installation process, external connectors, and
system requirements.
•
Chapter 3 — describes the unit’s configuration.
•
Chapter 4 — provides front panel operation information.
•
Chapter 5 — describes the unit’s theory of operation.
•
Chapter 6 — describes the maintenance of the unit, and provides troubleshooting
assistance.
•
Appendix A — provides data rate change instructions and the differences for
fixed and variable rate filters.
i
Preface
SDM-650B Satellite Modem
•
Appendix B — describes the unit’s remote control operation protocol and
command structure.
•
Appendix C — provides field compatibility specifications.
•
Appendix D — provides software change instructions.
•
Appendix E — describes the unit’s Automatic Gain Control (AGC) interface
option.
•
Appendix F — describes the asynchronous overhead channel unit option.
•
Appendix G — describes the Trojan interface option.
•
Glossary.
Conventions Used in this Manual
Cautions and Warnings
CAUTION
CAUTION indicates a hazardous situation that, if not avoided, may result in
minor or moderate injury. CAUTION may also be used to indicate other
unsafe practices or risks of property damage.
WARNING indicates a potentially hazardous situation that, if not avoided,
could result in death or serious injury.
WARNING
ii
Rev. 5
SDM-8000 Satellite Modem
Preface
References Used in this Manual
Military Standards
References to “MIL-STD-188” apply to the 114A series (i.e., MIL-STD-188-114A),
which provides electrical and functional characteristics of the unbalanced and balanced
voltage digital interface circuits applicable to both long haul and tactical
communications. Specifically, these references apply to the MIL-STD-188-114A
electrical characteristics for a balanced voltage digital interface circuit, Type 1 generator,
for the full range of data rates.
For more information, refer to the following document:
•
Department of Defense (DOD) MIL-STD-188-114A, “Electrical Characteristics
of Digital Interface Circuits.”
Trademarks
Product names mentioned in this manual may be trademarks or registered trademarks of
their respective companies and are hereby acknowledged.
Related Documents
The following documents are referenced in this manual:
•
•
•
•
•
•
•
•
Rev. 5
EFData Specification SP/1100
CCITT Recommendation V.35
CCITT Volume III Red Book
INTELSAT Document 308
INTELSAT Document 309
Bell System Publication 62411
AT&T Publication 62411
EFData ASYNC Breakout Panel Installation and Operation Manual
iii
Preface
SDM-650B Satellite Modem
European EMC Directive
In order to meet the European Electro-Magnetic Compatibility (EMC) Directive
(EN55022, EN50082-1), properly shielded cables for DATA I/O are required. More
specifically, these cables must be double-shielded from end-to-end, ensuring a continuous
ground shield.
The following information is applicable for the European Low Voltage Directive
(EN60950):
<HAR>
!
Type of power cord required for use in the European Community.
CAUTION: Double-pole/Neutral Fusing
ACHTUNG: Zweipolige bzw. Neutralleiter-Sicherung
International Symbols:
Alternating Current.
Fuse.
Safety Ground.
Chassis Ground.
Note: For additional symbols, refer to “Cautions and Warnings” listed earlier in this
preface.
Reporting Comments or Suggestions Concerning this Manual
Comments and suggestions regarding the content and design of this manual will be
appreciated. To submit comments, please contact the EFData Customer Support
Department according to the following information.
iv
Rev. 5
SDM-8000 Satellite Modem
Preface
Customer Support
Contact the EFData Customer Support Department for:
•
•
•
•
•
Product support
Information on returning a product
Information on upgrading a product
Product training
Reporting comments or suggestions concerning manuals
An EFData Customer Support representative may be reached at:
EFData Corporation
Attention: Customer Support Department
2105 West 5th Place
Tempe, Arizona 85281 USA
(602) 968-0447 (Main EFData Number)
(602) 517-2444 (Customer Support Desk)
(602) 921-9012 FAX
or, E-Mail can be sent to the Customer Support Department at:
[email protected]
To return an EFData product (in-warranty and out-of-warranty) for repair or replacement:
1. Request a Return Material Authorization (RMA) number from the EFData
Customer Support Department.
Be prepared to supply the Customer Support representative with the model
number, serial number, and a description of the problem.
2. To ensure that the product is not damaged during shipping, pack the product in
its original shipping carton/packaging.
3. Ship the product back to EFData. (Shipping charges should be prepaid.)
For more information regarding the warranty policies, refer to the disclaimer page
located behind the title page.
Rev. 5
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Preface
SDM-650B Satellite Modem
This page is intentionally left blank.
vi
Rev. 5
Table of Contents
CHAPTER 1. INTRODUCTION.................................................................................. 1–1
1.1 Purpose and Function ..................................................................................................................................1–2
1.2 Description ....................................................................................................................................................1–3
1.3 System Specification.....................................................................................................................................1–5
CHAPTER 2. INSTALLATION................................................................................... 2–1
2.1 Unpacking .....................................................................................................................................................2–1
2.2 External Connections...................................................................................................................................2–2
2.2.1 DATA I/O...............................................................................................................................................2–3
2.2.2 Remote (J6).............................................................................................................................................2–3
2.2.3 Fault (J7).................................................................................................................................................2–3
2.2.4 IF Output (CP1) ......................................................................................................................................2–4
2.2.5 IF Input (CP2).........................................................................................................................................2–4
2.2.6 AC Power ...............................................................................................................................................2–4
2.2.7 GROUND ...............................................................................................................................................2–5
2.3 System Requirements...................................................................................................................................2–5
2.4 System Installation .......................................................................................................................................2–6
CHAPTER 3. CONFIGURATION............................................................................... 3–1
3.1 Monitor and Control....................................................................................................................................3–1
3.1.1 Description of Options............................................................................................................................3–2
3.1.1.1 Remote Interface .............................................................................................................................3–2
3.1.1.2 Remote Baud Rate...........................................................................................................................3–3
3.1.1.3 Remote Address ..............................................................................................................................3–4
3.1.1.4 Battery .............................................................................................................................................3–4
3.1.1.5 Modulator/Coder Defaults...............................................................................................................3–5
3.1.1.6 Demodulator/Decoder Defaults.......................................................................................................3–5
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3.1.1.7 Utility Defaults ................................................................................................................................3–5
3.1.2 Remote Interface Specification...............................................................................................................3–6
3.1.3 M&C Theory of Operation .....................................................................................................................3–6
3.2 Digital Interfaces ..........................................................................................................................................3–7
3.2.1 RS-422 and MIL-STD-188-114 Interface ..............................................................................................3–7
3.2.1.1 Functional Description ....................................................................................................................3–7
3.2.1.2 Connector Pinouts .........................................................................................................................3–12
3.2.1.3 Specification..................................................................................................................................3–13
3.2.2 V.35 Interface .......................................................................................................................................3–14
3.2.2.1 Functional Description ..................................................................................................................3–14
3.2.2.2 Connector Pinouts .........................................................................................................................3–18
3.2.2.3 Specification..................................................................................................................................3–19
3.2.3 DS-1 Interface.......................................................................................................................................3–20
3.2.3.1 Functional Description ..................................................................................................................3–20
3.2.3.2 Connector Pinouts .........................................................................................................................3–23
3.2.3.3 Specification..................................................................................................................................3–23
3.2.4 G.703, 2048 kbit/s Interface .................................................................................................................3–24
3.2.4.1 Functional Description ..................................................................................................................3–24
3.2.4.2 Optional EXT CLK .......................................................................................................................3–26
3.2.4.3 Switch Configuration for G.703 2048 kbit/s Interface ..................................................................3–27
3.2.4.4 Connector Pinouts .........................................................................................................................3–27
3.2.4.5 G.703 2048 kbit/s Connector Board Option..................................................................................3–28
3.2.4.6 External Reference (J3) .................................................................................................................3–30
3.2.4.7 Send Data (J4) ...............................................................................................................................3–30
3.2.4.8 Receive Data (J5) ..........................................................................................................................3–30
3.2.4.9 Specification..................................................................................................................................3–31
3.2.5 Asynchronous Overhead Interface........................................................................................................3–31
3.2.5.1 Functional Description ..................................................................................................................3–31
3.2.5.2 Terrestrial Interface .......................................................................................................................3–32
3.2.5.3 Multiplexer ....................................................................................................................................3–35
3.2.5.4 Demultiplexer ................................................................................................................................3–35
3.2.5.5 Plesiochronous Buffer ...................................................................................................................3–36
3.2.5.6 Remote Interface Specification .....................................................................................................3–36
3.2.5.7 Interface Connector Pinouts ..........................................................................................................3–37
3.2.5.8 Asynchronous Interface Specifications .........................................................................................3–38
3.2.6 Asynchronous Breakout Panel..............................................................................................................3–39
3.3 Doppler Buffer............................................................................................................................................3–40
3.3.1 Buffer Setup..........................................................................................................................................3–44
3.3.1.1 Buffer Size.....................................................................................................................................3–46
3.3.1.2 Doppler..........................................................................................................................................3–46
3.3.1.3 Plesiochronous ..............................................................................................................................3–47
3.3.1.4 Frame/Multiframe Length .............................................................................................................3–47
3.3.1.5 Total Buffer Length.......................................................................................................................3–48
3.3.1.6 Converting .....................................................................................................................................3–48
3.4 Doppler Buffer Specification.....................................................................................................................3–49
3.5 I/O Connectors ...........................................................................................................................................3–49
3.6 Interface Clocking Options .......................................................................................................................3–50
3.6.1 Master/Slave .........................................................................................................................................3–50
3.6.1.1 Master/Slave RS-422 or V.35 .......................................................................................................3–51
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3.6.1.1.1 Modem Settings (Master).......................................................................................................3–52
3.6.1.1.2 Modem Settings (Slave).........................................................................................................3–52
3.6.1.2 Master/Slave G.703 .......................................................................................................................3–53
3.6.1.3 Master/Slave X.21 .........................................................................................................................3–54
3.6.1.3.1 Modem Settings (Master).......................................................................................................3–54
3.6.1.3.2 Modem Settings (Slave).........................................................................................................3–54
3.6.1.4 Master/Slave External Station Clock.............................................................................................3–55
3.6.1.4.1 Modem Settings (Master).......................................................................................................3–55
3.6.1.4.2 Modem Settings (Slave).........................................................................................................3–55
3.6.2 Master/Master .......................................................................................................................................3–56
3.6.2.1 Master/Master (Customer Clock) ..................................................................................................3–56
3.6.2.1.1 Modem Settings (Master).......................................................................................................3–57
3.6.2.2 Master/Master (Station Clock) ......................................................................................................3–58
3.6.2.2.1 Modem Settings (Master).......................................................................................................3–59
CHAPTER 4. OPERATION........................................................................................ 4–1
4.1 Front Panel ...................................................................................................................................................4–2
4.1.1 LED Indicators........................................................................................................................................4–3
4.1.2 Controls ..................................................................................................................................................4–3
4.1.3 Menus and Options Overview ................................................................................................................4–4
4.1.4 Menu Explanations .................................................................................................................................4–9
4.1.4.1 Select Configuration........................................................................................................................4–9
4.1.4.2 Select Monitor ...............................................................................................................................4–15
4.1.4.3 Select Faults ..................................................................................................................................4–16
4.1.4.3.1 Modulator Faults (Mod_Flts).................................................................................................4–17
4.1.4.3.2 Demodulator/Decoder Faults (Dmd_Flts)..............................................................................4–17
4.1.4.3.3 Common Equipment Faults (CEq_Flts) .................................................................................4–17
4.1.4.4 Select Stored Faults (StFaults) ......................................................................................................4–18
4.1.4.5 Select Utility..................................................................................................................................4–19
CHAPTER 5. THEORY OF OPERATION.................................................................. 5–1
5.1 Modulator .....................................................................................................................................................5–1
5.1.1 Specifications..........................................................................................................................................5–3
5.1.2 Theory of Operation ...............................................................................................................................5–5
5.2 Sequential Decoder/Demodulator Processor .............................................................................................5–7
5.2.1 Specification ...........................................................................................................................................5–8
5.2.2 Theory of Operation ...............................................................................................................................5–9
5.2.2.1 Demodulator Processor ...................................................................................................................5–9
5.2.2.2 Sequential Decoder........................................................................................................................5–10
5.2.2.2.1 Sequential Decoder BER Performance Specifications...........................................................5–12
5.3 Demodulator ...............................................................................................................................................5–16
5.3.1 Specifications........................................................................................................................................5–17
5.3.2 Theory of Operation .............................................................................................................................5–17
5.4 Reacquisition, Fast Acquisition, and Directed Sweep.............................................................................5–18
5.4.1 Reacquisition ........................................................................................................................................5–18
5.4.2 Fast Acquisition ....................................................................................................................................5–19
5.4.3 Directed Sweep.....................................................................................................................................5–20
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CHAPTER 6. MAINTENANCE................................................................................... 6–1
6.1 System Checkout ..........................................................................................................................................6–1
6.1.1 Modulator ...............................................................................................................................................6–1
6.1.2 Demodulator ...........................................................................................................................................6–2
6.1.3 Test Points ..............................................................................................................................................6–8
6.1.3.1 Modulator ........................................................................................................................................6–8
6.1.3.2 Demodulator....................................................................................................................................6–9
6.1.3.3 Sequential Decoder/Demod Card ..................................................................................................6–10
6.2 Fault Isolation.............................................................................................................................................6–11
6.2.1 Modulator Faults (Mod_Flts Menu) .....................................................................................................6–11
6.2.2 Demodulator/Decoder Faults (Dmd_Flts Menu) ..................................................................................6–12
6.2.3 Common Equipment Faults (CEq_Flts Menu) .....................................................................................6–14
6.3 Interface Fault Isolation ............................................................................................................................6–15
6.3.1 Transmit Faults (TX_INTF) .................................................................................................................6–15
6.3.2 Receive Faults (RX_INTF)...................................................................................................................6–16
6.4 Module Replacement .................................................................................................................................6–21
6.5 Module Identification.................................................................................................................................6–21
APPENDIX A. DATA RATES AND FILTERS............................................................A–1
A.1 Fixed Rate Filters ....................................................................................................................................... A–1
A.1.1 Data Rate Change Instructions.............................................................................................................. A–1
A.1.2 Hardware Configuration ....................................................................................................................... A–5
A.2 Variable Rate Filters.................................................................................................................................. A–6
A.2.1 Data Rate Change Instructions.............................................................................................................. A–6
A.2.2 Hardware Configuration ....................................................................................................................... A–7
A.2.3 Utility .................................................................................................................................................... A–9
APPENDIX B. REMOTE CONTROL OPERATION ...................................................B–1
B.1 Standard Version........................................................................................................................................ B–1
B.1.1 General .................................................................................................................................................. B–2
B.1.2 Message Structure ................................................................................................................................. B–2
B.1.2.1 Start Character ............................................................................................................................... B–2
B.1.2.2 Device Address.............................................................................................................................. B–3
B.1.2.3 Command/Response ...................................................................................................................... B–4
B.1.2.4 End Character ................................................................................................................................ B–4
B.1.3 Configuration Commands/Responses ................................................................................................... B–5
B.1.3.1 Set Modulator Frequency............................................................................................................... B–5
B.1.3.2 Set RF Output ................................................................................................................................ B–5
B.1.3.3 Set Demodulator Frequency .......................................................................................................... B–5
B.1.3.4 Set Modulator Power Offset .......................................................................................................... B–6
B.1.3.5 Set Modulator Output Power Level ............................................................................................... B–6
B.1.3.6 Modulator Rate .............................................................................................................................. B–7
B.1.3.6.1 Modulator Filter Rate Assignment ......................................................................................... B–7
B.1.3.6.2 Select Modulator Rate ............................................................................................................ B–8
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B.1.3.6.3 Select Modulator Rate Variable ............................................................................................. B–8
B.1.3.7 Demodulator Rate .......................................................................................................................... B–9
B.1.3.7.1 Demodulator Filter Rate Assignment ..................................................................................... B–9
B.1.3.7.2 Select Demodulator Rate ...................................................................................................... B–10
B.1.3.7.3 Select Demodulator Rate Variable ....................................................................................... B–10
B.1.3.8 Scrambler Enable......................................................................................................................... B–10
B.1.3.9 Descrambler Enable..................................................................................................................... B–10
B.1.3.10 Differential Encoder Enable ...................................................................................................... B–11
B.1.3.11 Transmit Clock .......................................................................................................................... B–11
B.1.3.12 Receive Clock ............................................................................................................................ B–11
B.1.3.13 Baseband Loopback................................................................................................................... B–11
B.1.3.14 RF Loopback ............................................................................................................................. B–12
B.1.3.15 IF Loopback............................................................................................................................... B–12
B.1.3.16 Time of Day............................................................................................................................... B–12
B.1.3.17 Date............................................................................................................................................ B–13
B.1.3.18 Remote....................................................................................................................................... B–13
B.1.3.19 Clear Stored Faults .................................................................................................................... B–13
B.1.3.20 BER Threshold .......................................................................................................................... B–13
B.1.3.21 Sweep Reacquisition.................................................................................................................. B–14
B.1.3.22 Fast Acquisition Mode............................................................................................................... B–14
B.1.3.22.1 Sweep Center Frequency.................................................................................................... B–15
B.1.3.22.2 Sweep Width Range ........................................................................................................... B–15
B.1.3.22.3 Sweep Direction ................................................................................................................. B–16
B.1.3.23 Modem Operation Mode............................................................................................................ B–16
B.1.3.24 Buffer Control Mode ................................................................................................................. B–16
B.1.3.24.1 Buffer Clock ....................................................................................................................... B–17
B.1.3.24.2 Interface Buffer Center....................................................................................................... B–17
B.1.3.24.3 Interface Buffer Size .......................................................................................................... B–17
B.1.4. Status Commands/Responses............................................................................................................. B–18
B.1.4.1 Configuration............................................................................................................................... B–18
B.1.4.1.1 Modulator/Coder Status ....................................................................................................... B–18
B.1.4.1.2 Modulator/Coder Program.................................................................................................... B–18
B.1.4.1.3 Demodulator/Decoder Configuration Status ........................................................................ B–19
B.1.4.1.4 Demodulator/Decoder Configuration Program .................................................................... B–20
B.1.4.2 Modem Faults Status (Summary) ................................................................................................ B–20
B.1.4.3 Modulator Status.......................................................................................................................... B–21
B.1.4.4 Demodulator Status...................................................................................................................... B–21
B.1.4.5 Common Equipment Status ......................................................................................................... B–22
B.1.4.6 Interface Receive Side Status ...................................................................................................... B–22
B.1.4.7 BER Status................................................................................................................................... B–23
B.1.4.7.1 Raw BER.............................................................................................................................. B–23
B.1.4.7.2 Corrected BER ..................................................................................................................... B–23
B.1.4.8 Eb/N0 Status.................................................................................................................................. B–24
B.1.4.9 Modulator Rate Status ................................................................................................................. B–24
B.1.4.10 Demodulator Rate Status ........................................................................................................... B–24
B.1.4.11 Receive Signal Level Status ...................................................................................................... B–25
B.1.4.12 Current Sweep Value ................................................................................................................. B–25
B.1.4.13 Stored Faults .............................................................................................................................. B–26
B.1.4.13.1 Modulator Stored Faults ..................................................................................................... B–26
B.1.4.13.2 Demodulator Stored Faults................................................................................................. B–26
B.1.4.13.3 Common Equipment Stored Faults..................................................................................... B–27
B.1.4.13.4 Interface Receive Side Status Stored Faults ....................................................................... B–27
B.1.4.14 Bulk Consolidated Status........................................................................................................... B–28
B.1.4.15 Bulk Consolidated Analog Status .............................................................................................. B–30
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B.1.4.16 Bulk Consolidated Status Faults ................................................................................................ B–30
B.1.4.17 Change Status ............................................................................................................................ B–31
B.1.4.18 Equipment Type......................................................................................................................... B–32
B.2 Asynchronous Overhead Interface Support Option ............................................................................. B–33
B.2.1 General ................................................................................................................................................ B–33
B.2.2 Message Structure ............................................................................................................................... B–33
B.2.2.1 Start Character ............................................................................................................................. B–34
B.2.2.2 Device Address............................................................................................................................ B–34
B.2.2.3 Command/Response .................................................................................................................... B–35
B.2.2.4 End Character .............................................................................................................................. B–35
B.2.3 Modulator Configuration Commands ................................................................................................. B–36
B.2.3.1 Set Modulator Frequency............................................................................................................. B–36
B.2.3.2 Set RF Output .............................................................................................................................. B–36
B.2.3.3 Set Modulator Power Offset ........................................................................................................ B–36
B.2.3.4 Set Modulator Output Power Level ............................................................................................. B–37
B.2.3.5 Modulator Rate ............................................................................................................................ B–38
B.2.3.5.1 Modulator Filter Rate Assignment ....................................................................................... B–38
B.2.3.5.2 Select Modulator Rate .......................................................................................................... B–39
B.2.3.5.3 Select Modulator Rate Variable ........................................................................................... B–39
B.2.3.6 Scrambler Enable......................................................................................................................... B–39
B.2.3.7 Differential Encoder Enable ........................................................................................................ B–40
B.2.4 Demodulator Configuration Commands ............................................................................................. B–40
B.2.4.1 Set Demodulator Frequency ........................................................................................................ B–40
B.2.4.2 Demodulator Rate ........................................................................................................................ B–40
B.2.4.2.1 Demodulator Filter Rate Assignment ................................................................................... B–41
B.2.4.2.2 Select Demodulator Rate ...................................................................................................... B–41
B.2.4.2.3 Select Demodulator Rate Variable ....................................................................................... B–41
B.2.4.3 Descramble Enable ...................................................................................................................... B–42
B.2.4.4 RF Loopback ............................................................................................................................... B–42
B.2.4.5 IF Loopback................................................................................................................................. B–42
B.2.4.6 BER Threshold ............................................................................................................................ B–42
B.2.4.7 Sweep Reacquisition.................................................................................................................... B–43
B.2.4.8 Fast Acquisition Mode................................................................................................................. B–43
B.2.4.8.1 Sweep Center Frequency...................................................................................................... B–44
B.2.4.8.2 Sweep Width Range ............................................................................................................. B–44
B.2.4.8.3 Sweep Direction ................................................................................................................... B–45
B.2.5 Interface Configuration Commands .................................................................................................... B–45
B.2.5.1 Transmit Clock ............................................................................................................................ B–45
B.2.5.2 Buffer Clock ................................................................................................................................ B–45
B.2.5.3 Receive Clock .............................................................................................................................. B–46
B.2.5.4 External Reference Frequency..................................................................................................... B–46
B.2.5.5 Interface Loopback ...................................................................................................................... B–46
B.2.5.6 Baseband Loopback..................................................................................................................... B–46
B.2.5.7 Interface Coding Format Transmit............................................................................................... B–47
B.2.5.8 Interface Coding Format Receive ................................................................................................ B–47
B.2.5.9 Interface Buffer Center ................................................................................................................ B–47
B.2.5.10 Interface Buffer Size.................................................................................................................. B–47
B.2.5.11 Transmit Overhead Baud Rate................................................................................................... B–48
B.2.5.12 Receive Overhead Baud Rate .................................................................................................... B–48
B.2.5.13 Overhead Channels Character Length ....................................................................................... B–48
B.2.5.14 Overhead Channels Stop Bits .................................................................................................... B–48
B.2.5.15 Overhead Channels Parity ......................................................................................................... B–49
B.2.5.16 Interface Substitution Pattern (Transmit 2047 Pattern) ............................................................. B–49
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Table of Contents
B.2.6 System Commands/Responses ............................................................................................................ B–49
B.2.6.1 Time of Day................................................................................................................................. B–49
B.2.6.2 Date.............................................................................................................................................. B–50
B.2.6.3 Remote......................................................................................................................................... B–50
B.2.6.4 Clear Stored Faults ...................................................................................................................... B–50
B.2.6.5 Modem Operation Mode.............................................................................................................. B–51
B.2.7 Automatic Uplink Power Control (AUPC) Configuration Commands............................................... B–51
B.2.7.1 Local Modem AUPC Commands ................................................................................................ B–51
B.2.7.1.1 Local AUPC Enable ............................................................................................................. B–51
B.2.7.1.2 Nominal AUPC Power Level ............................................................................................... B–51
B.2.7.1.3 Maximum AUPC Power Limit............................................................................................. B–52
B.2.7.1.4 Minimum AUPC Power Limit ............................................................................................. B–52
B.2.7.1.5 Eb/N0 Target AUPC Set Point............................................................................................... B–52
B.2.7.1.6 Maximum AUPC Tracking Rate .......................................................................................... B–52
B.2.7.1.7 AUPC Local Carrier Loss Action......................................................................................... B–53
B.2.7.1.8 AUPC Remote Carrier Loss Action ..................................................................................... B–53
B.2.7.2 Remote Modem AUPC Commands............................................................................................. B–53
B.2.7.2.1 Remote AUPC Enable.......................................................................................................... B–53
B.2.7.2.2 Remote Interface Substitution Pattern (Transmit 2047 Pattern)........................................... B–54
B.2.7.2.3 Remote Interface Baseband Loopback ................................................................................. B–54
B.2.7.2.4 Remote Interface Read Error Status (Received 2047 Pattern) ............................................. B–54
B.2.8 Status Commands/Responses.............................................................................................................. B–55
B.2.8.1 Configuration Status .................................................................................................................... B–55
B.2.8.1.1 Modulator/Coder Configuration Status ................................................................................ B–55
B.2.8.1.2 Modulator/Coder Configuration Program ............................................................................ B–56
B.2.8.1.3 Demodulator/Decoder Configuration Status ........................................................................ B–57
B.2.8.1.4 Demodulator/Decoder Configuration Program .................................................................... B–58
B.2.8.1.5 Interface Configuration Status.............................................................................................. B–59
B.2.8.1.6 AUPC Configuration Status ................................................................................................. B–59
B.2.8.2 Modem Faults Status (Summary) ................................................................................................ B–60
B.2.8.3 Modulator Status.......................................................................................................................... B–60
B.2.8.4 Demodulator Status...................................................................................................................... B–60
B.2.8.5 Common Equipment Status ......................................................................................................... B–61
B.2.8.6 Interface Transmit Side Status ..................................................................................................... B–61
B.2.8.7 Interface Receive Side Status ...................................................................................................... B–61
B.2.8.8 Bit Error Rate Status .................................................................................................................... B–62
B.2.8.8.1 Raw BER.............................................................................................................................. B–62
B.2.8.8.2 Corrected BER ..................................................................................................................... B–62
B.2.8.9 Eb/N0 ............................................................................................................................................ B–63
B.2.8.10 Modulator Rate .......................................................................................................................... B–63
B.2.8.11 Demodulator Rate ...................................................................................................................... B–63
B.2.8.12 Receive Signal Level ................................................................................................................. B–64
B.2.8.13 Current Sweep Value ................................................................................................................. B–64
B.2.8.14 Interface Buffer Fill Status ........................................................................................................ B–64
B.2.8.15 Interface Read Error Status........................................................................................................ B–64
B.2.8.16 Stored Faults .............................................................................................................................. B–65
B.2.8.16.1 Modulator Stored Faults ..................................................................................................... B–65
B.2.8.16.2 Demodulator Stored Faults................................................................................................. B–65
B.2.8.16.3 Common Equipment Stored Faults..................................................................................... B–66
B.2.8.16.4 Interface Transmit Side Stored Faults ................................................................................ B–66
B.2.8.16.5 Interface Receive Side Stored Faults.................................................................................. B–66
B.2.8.17 Bulk Consolidated Status........................................................................................................... B–67
B.2.8.18 Bulk Consolidated Analog Status .............................................................................................. B–69
B.2.8.19 Bulk Consolidated Status Faults ................................................................................................ B–70
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B.2.8.20 Change Status ............................................................................................................................ B–72
B.2.8.21 Equipment Type......................................................................................................................... B–72
B.2.8.22 Bulk Consolidated Status AUPC ............................................................................................... B–72
APPENDIX C. FIELD COMPATIBILITY ....................................................................C–1
C.1 SDM-650B Standard Modem.................................................................................................................... C–1
C.2 SDM-650B Fairchild-Compatible Modem ............................................................................................... C–2
C.3 SDM-650B Aydin Data Rate Modem ....................................................................................................... C–2
C.4 SDM-650B Comstream Modem ................................................................................................................ C–2
APPENDIX D. SOFTWARE CHANGE INSTRUCTIONS...........................................D–1
APPENDIX E. AGC INTERFACE ..............................................................................E–1
E.1 Connector Pinouts ...................................................................................................................................... E–2
E.2 Installation Instructions............................................................................................................................. E–2
E.2.1 Parts Required ....................................................................................................................................... E–2
E.2.2 Installation Procedure............................................................................................................................ E–3
APPENDIX F. ASYNCHRONOUS OVERHEAD CHANNEL UNIT ............................ F–1
F.1 Functional Description of ASYNC Overhead Channel Unit .................................................................. F–2
F.1.1 Terrestrial Interface ................................................................................................................................F–4
F.1.2 Multiplexer .............................................................................................................................................F–6
F.1.3 Demultiplexer .........................................................................................................................................F–6
F.1.4 Plesiochronous Buffer ............................................................................................................................F–7
F.2 ASYNC Interface Connector Pinouts ....................................................................................................... F–8
F.3 ASYNC Interface Specifications................................................................................................................ F–9
F.4 Functional Description of ASYNC Overhead Channel Unit with AUPC............................................ F–10
F.4.1 AUPC ...................................................................................................................................................F–10
F.4.2 Modem-to-Modem Channel for Remote M&C ....................................................................................F–11
F.5 Front Panel Operation ............................................................................................................................. F–12
F.5.1 Menus and Options Overview ..............................................................................................................F–13
F.5.2 Menu Explanations ...............................................................................................................................F–20
F.5.2.1 Select Configuration......................................................................................................................F–20
F.5.2.1.1 Configuration Modulator .......................................................................................................F–21
F.5.2.1.2 Configuration Demodulator ...................................................................................................F–23
F.5.2.1.3 Configuration Interface..........................................................................................................F–25
F.5.2.1.4 Configuration AUPC .............................................................................................................F–28
F.5.2.2 Select Monitor...............................................................................................................................F–29
F.5.2.3 Select Faults ..................................................................................................................................F–30
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SDM-650B Satellite Modem
Table of Contents
F.5.2.3.1 Modulator Faults (Mod_FLTS) .............................................................................................F–31
F.5.2.3.2 Demodulator/Decoder Faults (Dmd_Flts) .............................................................................F–31
F.5.2.3.3 Common Equipment Faults (CEq_Flts).................................................................................F–31
F.5.2.3.4 Transmit Faults (TX_INTF) ..................................................................................................F–32
F.5.2.3.5 Receive Faults (RX_INTF)....................................................................................................F–32
F.5.2.4 Select Stored Faults (StFaults) ......................................................................................................F–33
F.5.2.5 Select Remote................................................................................................................................F–34
F.5.2.5.1 Remote Configuration............................................................................................................F–34
F.5.2.5.2 Remote Monitor .....................................................................................................................F–34
F.5.2.6 Select Utility..................................................................................................................................F–35
APPENDIX G. TROJAN INTERFACE ...................................................................... G–1
G.1 Functional Description ..............................................................................................................................G–1
G.2 Connector Pinouts......................................................................................................................................G–5
G.3 Specification................................................................................................................................................G–6
G.3.1 MIL-STD-188-114 Parameters............................................................................................................. G–6
G.3.2 Clock Synthesizer/Dejitter Circuit ........................................................................................................ G–6
G.3.3 Doppler Buffer Parameters ................................................................................................................... G–6
G.4 Configuration Guide ..................................................................................................................................G–7
G.4.1 Modulator/Coder Defaults .................................................................................................................... G–7
G.4.2 Demodulator/Decoder Defaults (Dmd_Flts)......................................................................................... G–8
G.4.3 Interface Defaults.................................................................................................................................. G–8
G.5 Front Panel Operation...............................................................................................................................G–9
G.5.1 Menus and Options Overview .............................................................................................................. G–9
G.5.2 Menu Explanations ............................................................................................................................. G–14
G.5.2.1 Select Configuration .................................................................................................................... G–14
G.5.2.2 Select Monitor ............................................................................................................................. G–14
G.5.2.3 Select Faults................................................................................................................................. G–14
G.5.2.3.1 Modulator Faults (Mod_Flts) ............................................................................................... G–14
G.5.2.3.2 Demodulator/Decoder Faults (Dmd_Flts)............................................................................ G–14
G.5.2.3.3 Common Equipment Faults (CEq_Flts) ............................................................................... G–14
G.5.2.4 Select Stored Faults (StFaults) .................................................................................................... G–15
G.5.2.5 Select Utility ................................................................................................................................ G–15
G.6 Remote Control Operation......................................................................................................................G–16
G.6.1 General................................................................................................................................................ G–16
G.6.1.1 Message Structure........................................................................................................................ G–16
G.6.1.1.1 Start Character ...................................................................................................................... G–17
G.6.1.1.2 Device Address .................................................................................................................... G–17
G.6.2 Command/Response............................................................................................................................ G–18
G.6.3 End Character ..................................................................................................................................... G–18
G.6.4 Configuration Commands/Responses ................................................................................................. G–19
G.6.4.1 Modulator .................................................................................................................................... G–19
G.6.4.1.1 Set Modulator Frequency ..................................................................................................... G–19
G.6.4.1.2 Set RF Output....................................................................................................................... G–19
G.6.4.1.3 Modulator Rate..................................................................................................................... G–20
G.6.4.1.3.1 Modulator Filter Rate Assignment................................................................................ G–20
G.6.4.1.3.2 Select Modulator Rate................................................................................................... G–21
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G.6.4.1.3.3 Select Modulator Rate Variable.................................................................................... G–21
G.6.4.1.3.4 Set Modulator Power Offset ......................................................................................... G–21
G.6.4.1.3.5 Set Modulator Output Power Level .............................................................................. G–22
G.6.4.1.3.6 Scrambler Enable .......................................................................................................... G–22
G.6.4.1.3.7 Differential Encoder Enable ......................................................................................... G–22
G.6.4.2 Demodulator ................................................................................................................................ G–23
G.6.4.2.1 Set Demodulator Frequency................................................................................................. G–23
G.6.4.2.2 Demodulator Rate ................................................................................................................ G–23
G.6.4.2.2.1 Demodulator Filter Rate Assignment ........................................................................... G–24
G.6.4.2.2.2 Select Demodulator Rate .............................................................................................. G–24
G.6.4.2.2.3 Select Demodulator Rate Variable................................................................................ G–24
G.6.4.2.3 Descramble Enable............................................................................................................... G–25
G.6.4.2.4 IF Loopback ......................................................................................................................... G–25
G.6.4.2.5 RF Loopback........................................................................................................................ G–25
G.6.4.2.6 Sweep Reacquisition ............................................................................................................ G–25
G.6.4.2.7 Fast Acquisition Mode ......................................................................................................... G–26
G.6.4.2.8 Sweep Center Frequency...................................................................................................... G–26
G.6.4.2.9 Sweep Width Range............................................................................................................. G–27
G.6.4.2.10 Sweep Direction ................................................................................................................. G–27
G.6.4.2.11 Bit Error Rate Threshold .................................................................................................... G–27
G.6.4.3 Interface/Doppler Buffer ............................................................................................................. G–28
G.6.4.3.1 Baseband Loopback ............................................................................................................. G–28
G.6.4.3.2 Transmit Clock..................................................................................................................... G–28
G.6.4.3.3 Receive Clock ...................................................................................................................... G–28
G.6.4.3.4 External Reference Frequency ............................................................................................. G–28
G.6.4.3.5 Interface Reference Clock.................................................................................................... G–29
G.6.4.3.6 Interface Buffer Center ........................................................................................................ G–29
G.6.4.3.7 Interface Buffer Depth ......................................................................................................... G–29
G.6.4.4 System Commands/Responses .................................................................................................... G–30
G.6.4.4.1 Time of Day ......................................................................................................................... G–30
G.6.4.4.2 Date ...................................................................................................................................... G–30
G.6.4.4.3 Remote ................................................................................................................................. G–31
G.6.4.4.4 Clear Stored Faults............................................................................................................... G–31
G.6.4.4.5 Modem Operation Mode ...................................................................................................... G–31
G.6.4.5 Status Commands/Responses ...................................................................................................... G–32
G.6.4.5.1 Configuration ....................................................................................................................... G–32
G.6.4.5.1.1 Modulator/Coder Configuration Status......................................................................... G–32
G.6.4.5.1.2 Modulator/Coder Configuration Program..................................................................... G–33
G.6.4.5.1.3 Demodulator/Decoder Configuration Status................................................................. G–33
G.6.4.5.1.4 Demodulator/Decoder Configuration Program............................................................. G–34
G.6.4.5.1.5 Interface Configuration Status ...................................................................................... G–34
G.6.4.5.2 Modem Faults Status (Summary)......................................................................................... G–35
G.6.4.5.3 Modulator Status .................................................................................................................. G–35
G.6.4.5.4 Demodulator Status .............................................................................................................. G–35
G.6.4.5.5 Common Equipment Status.................................................................................................. G–36
G.6.4.5.6 Bit Error Rate Status ............................................................................................................ G–36
G.6.4.5.6.1 Raw BER ...................................................................................................................... G–36
G.6.4.5.6.2 Corrected BER.............................................................................................................. G–37
G.6.4.5.7 Eb/N0 ..................................................................................................................................... G–37
G.6.4.5.8 Modulator Rate..................................................................................................................... G–37
G.6.4.5.9 Demodulator Rate ................................................................................................................ G–38
G.6.4.5.10 Receive Signal Level.......................................................................................................... G–38
G.6.4.5.11 Current Sweep Value ......................................................................................................... G–38
G.6.4.5.12 Stored Faults ...................................................................................................................... G–38
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SDM-650B Satellite Modem
Table of Contents
G.6.4.5.12.1 Modulator Stored Faults ............................................................................................. G–39
G.6.4.5.12.2 Demodulator Stored Faults ......................................................................................... G–39
G.6.4.5.12.3 Common Equipment Stored Faults ............................................................................. G–39
G.6.4.5.13 Bulk Consolidated Status ................................................................................................... G–40
G.6.4.5.14 Bulk Consolidated Analog Status ...................................................................................... G–42
G.6.4.5.15 Bulk Consolidated Status Faults ........................................................................................ G–42
G.6.4.5.16 Change Status..................................................................................................................... G–43
G.6.4.5.17 Equipment Type ................................................................................................................. G–44
GLOSSARY ............................................................................................................... g–1
Rev. 5
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SDM-650B Satellite Modem
Figures
Figure 1-1. SDM-650B....................................................................................................................................1–1
Figure 1-2. Satellite Communications System with an SDM-650B ................................................................1–2
Figure 1-3. Modular Construction ...................................................................................................................1–4
Figure 1-4. Sequential Decoder BER Performance Curves (1/2 Rate)............................................................1–8
Figure 1-5. Sequential Decoder BER Performance Curves (3/4 Rate)............................................................1–9
Figure 1-6. Sequential Decoder BER Performance Curves (7/8 Rate)..........................................................1–10
Figure 1-7. Viterbi Decoder BER Performance Curves (1/2 Rate) ...............................................................1–11
Figure 1-8. SDM-650B Typical Output Spectrum ........................................................................................1–12
Figure 2-1. SDM-650B Rear Panel View ........................................................................................................2–2
Figure 3-1. M&C Card ....................................................................................................................................3–2
Figure 3-2. RS-422 and MIL-STD-188-114 Interface Board..........................................................................3–7
Figure 3-3. RS-422 and MIL-STD-188-114 Block Diagram ..........................................................................3–8
Figure 3-4. V.35 Interface Card.....................................................................................................................3–14
Figure 3-5. V.35 Interface Block Diagram ....................................................................................................3–15
Figure 3-6. DS-1 Interface Card ....................................................................................................................3–20
Figure 3-7. DS-1 Interface Block Diagram....................................................................................................3–21
Figure 3-8. G.703 2048 kbit/s Interface Card................................................................................................3–24
Figure 3-9. G.703 2048 Interface Block Diagram .........................................................................................3–25
Figure 3-10. G.703 2048 kbit/s Interface Connector Board (Optional).........................................................3–28
Figure 3-11. G.703 2048 kbit/s Connector Board Schematic Diagram .........................................................3–29
Figure 3-12. Asynchronous Overhead Interface Block Diagram ..................................................................3–32
Figure 3-13. Asynchronous Overhead Jumpers.............................................................................................3–33
Figure 3-14. AS/3812 Doppler Buffer Daughter Card ..................................................................................3–43
Figure 3-15. Clock Slip Diagram...................................................................................................................3–45
Figure 3-16. RS-422 or V.35 Master Slave Configuration............................................................................3–51
Figure 3-17. G.703 Master Slave Configuration ...........................................................................................3–53
Figure 3-18. X.21 Master/Slave Configuration .............................................................................................3–54
Figure 3-19. G.703 Master Slave Configuration ...........................................................................................3–55
Figure 3-20. Master/Master Customer Clock Configuration .........................................................................3–56
Figure 3-21. Master/Master Station Clock Configuration Diagram ..............................................................3–58
Figure 4-1. SDM-650B Front Panel View.......................................................................................................4–2
Figure 5-1. Modulator Block Diagram ............................................................................................................5–2
Figure 5-2. Modulator Output Spectral Occupancy.........................................................................................5–4
Figure 5-3. Decoder Block Diagram................................................................................................................5–7
Figure 5-4. Sequential Decoder BER Performance Curves (1/2 Rate)..........................................................5–13
Figure 5-5. Sequential Decoder BER Performance Curves (3/4 Rate)..........................................................5–14
Figure 5-6. Sequential Decoder BER Performance Curves (7/8 Rate)..........................................................5–15
Figure 5-7. Demodulator Block Diagram ......................................................................................................5–16
Figure 6-1. Typical Output Spectrum ..............................................................................................................6–4
Figure 6-2. Typical Output Spectrum ..............................................................................................................6–4
Figure 6-3. Typical Eye Pattern with Noise (Approximately 7.5 dB Eb/N0) ...................................................6–6
Figure 6-4. Typical Eye Pattern without Noise ...............................................................................................6–6
Figure 6-5. Typical Eye Constellation with Noise (Approximately 7.5 dB Eb/N0) .........................................6–7
Figure 6-6. Typical Eye Constellation without Noise......................................................................................6–7
Figure 6-7. Modulator Test Points...................................................................................................................6–8
Figure 6-8. Demodulator Test Points...............................................................................................................6–9
Figure 6-9. Sequential Decoder/Demod Card Test Points.............................................................................6–10
Figure 6-10. Rear View Without Cover.........................................................................................................6–20
Figure A-1. Modulator Filter Card Change .................................................................................................... A–2
Figure A-2. Demodulator Filter Card Change ................................................................................................ A–4
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Rev. 5
SDM-650B Satellite Modem
Figure E-1.
Figure E-2.
Figure E-3.
Figure F-1.
Figure F-2.
Figure G-1.
Rev. 5
Table of Contents
Rear Panel View .......................................................................................................................... E–2
Wiring Diagram........................................................................................................................... E–4
AGC Adapter Board .................................................................................................................... E–5
Asynchronous Overhead Interface Block Diagram ......................................................................F–3
Asynchronous Overhead Interface Board.....................................................................................F–5
Trojan Interface Block Diagram ................................................................................................. G–2
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Table of Contents
SDM-650B Satellite Modem
Tables
Table 1-1. Operating Specifications ................................................................................................................1–5
Table 1-2. BER Performance Specifications ...................................................................................................1–7
Table 2-1. Rear Panel Connectors ...................................................................................................................2–2
Table 3-1. AS/0627-3 Rev. E Board Jumper Selection .................................................................................3–11
Table 3-2. AS/0627-2 Rev. E Board Jumper Selection .................................................................................3–17
Table 3-3. Equalizer Control .........................................................................................................................3–22
Table 3-4. G.703, 2048 kbit/s Interface Switch Configurations ....................................................................3–26
Table 3-5. G.703 2048 kbit/s Interface Connector Jumpers ..........................................................................3–29
Table 3-6. Asynchronous Overhead Jumper Table........................................................................................3–34
Table 3-7. Data Rate Jumper Table ...............................................................................................................3–34
Table 3-8. Jumper Selections.........................................................................................................................3–41
Table 3-9. INTELSAT Delay Variations.......................................................................................................3–41
Table 4-1. Main Front Panel Menu (Standard)................................................................................................4–4
Table 4-2. Select Configuration Menu ............................................................................................................4–5
Table 4-3. Select Monitor Menu......................................................................................................................4–6
Table 4-4. Select Faults Menu .........................................................................................................................4–6
Table 4-5. Select Stored Faults (StFaults) Menu .............................................................................................4–7
Table 4-6. Select Utility Menu.........................................................................................................................4–8
Table 6-1. EFData Conversion of (S+N)/N to S/N and Eb/N0 for Various Code Rates...................................6–5
Table 6-2. Programmable Data Rates for the Variable Rate SDM-650B Modem.........................................6–17
Table 6-3. EFData Part Numbers for SDM-650B Modules...........................................................................6–22
Table D-1. EFData M&C Viterbi Decoder Firmware .................................................................................... D–2
Table F-1. Asynchronous Overhead Jumpers..................................................................................................F–5
Table F-2. Data Rate Jumpers..........................................................................................................................F–5
Table F-3. Main Front Panel Menu with Asynchronous Overhead (with AUPC) ........................................F–13
Table F-4. Select Configuration Modulator Menu (with AUPC) ..................................................................F–13
Table F-5. Select Configuration Demodulator Menu (with AUPC) ..............................................................F–14
Table F-6. Select Configuration Interface Menu (with AUPC).....................................................................F–15
Table F-7. Select Configuration AUPC Menu (with AUPC) ........................................................................F–16
Table F-8. Select Monitor Menu (with AUPC) .............................................................................................F–16
Table F-9. Select Faults Menu (with AUPC).................................................................................................F–17
Table F-10. Select Stored Faults (StFaults) Menu (with AUPC) ..................................................................F–18
Table F-11. Select Remote Menu (with AUPC) ............................................................................................F–18
Table F-12. Select Utility Menu (with AUPC) ..............................................................................................F–19
Table G-1. Main Front Panel Menu (Trojan Interface) .................................................................................. G–9
Table G-2. Select Configuration Modulator Menu....................................................................................... G–10
Table G-3. Select Configuration Demodulator Menu................................................................................... G–10
Table G-4. Select Configuration Interface Menu ......................................................................................... G–11
Table G-5. Select Monitor Menu .................................................................................................................. G–11
Table G-6. Select Faults (StFaults) Menu..................................................................................................... G–12
Table G-7. Select StFaults Menu .................................................................................................................. G–13
Table G-8. Select Utility Menu..................................................................................................................... G–13
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Rev. 5
Chapter 1.
INTRODUCTION
This manual describes the SDM-650B satellite modem, referred to in this document as
“the modem” (Figure 1-1).
Figure 1-1. SDM-650B
Rev. 5
1–1
Introduction
SDM-650B Satellite Modem
1.1 Purpose and Function
The modem is a high performance, full-duplex, Bi-Phase Shift Keying/Quadrature Phase
Shift Keying (BPSK/QPSK), digital modulator/demodulator (modem), for Frequency
Division Multiple Access (FDMA) satellite communication systems.
The modem provides an interface between Single Channel Per Carrier (SCPC) fixed-rate
terminal equipment, having a data rate of 19.2 kbit/s to 3.584 Mbit/s.
The modem also provides an interface between IF converter equipment operating in a 50 to
90 MHz band, or 100 to 180 MHz band (Figure 1-2).
CUSTOMER
DATA
DIGITAL
INTERFACE
ENCODER/
MODULATOR
TRANSMIT
RF EQUIPMENT
ANTENNA
REMOTE
SERIAL
INTERFACE
MICROCOMPUTER
POWER
SUPPLY
AC POWER
FAULT
INDICATORS
SDM-650B
SATELLITE
DATA MODEM
DEMODULATOR/
DECODER
RECEIVE
RF EQUIPMENT
Figure 1-2. Satellite Communications System with an SDM-650B
1–2
Rev. 5
SDM-650B Satellite Modem
Introduction
The modem contains:
•
Built-in scrambler/descrambler
•
Differential encoder/decoder
•
Transmit and receive frequency synthesizers
•
Multi-rate Forward Error Correction (FEC) convolutional encoder-sequential
decoder (Viterbi K=7 is optional)
The modem provides high performance with:
•
•
•
•
Narrow occupied bandwidth
Automatic signal acquisition
High flexibility
Extensive online monitoring circuits
1.2 Description
The modem is a complete, self-contained unit in a standard 19” rack-mountable enclosure
weighing approximately 25 lbs.
The modem is of modular construction (Figure 1-3).
The chassis assembly (with the front and rear panel) encloses several Printed Circuit Boards
(PCBs). The backplane PCB is mounted on the chassis assembly, and contains receptacles
for five plug-in PCBs.
Rev. 5
1–3
Introduction
SDM-650B Satellite Modem
Figure 1-3. Modular Construction
Test points are located on the front board edge of the modulator, demodulator, and decoder
PCBs. Refer to Section 6.1.4 for listings and diagrams of the test points.
All controls and indicators for operation of the modem are located on the front panel. For
more information, refer to Chapter 4.
The chassis also contains the power supply; a fan is located on the rear panel.
The modem consists of the following assemblies:
Assembly
Chassis with Power Supply
PCB, M&C
PCB, Modulator
PCB, Demodulator
PCB, Sequential Decoder
PCB, Front Panel Control Board
PCB, Mother Board
PCB, Digital Interface V.35
PCB, Digital Interface DS1
PCB, Digital Interface MIL-STD-188-114
PCB, Doppler Buffer
PCB, Asynchronous Overhead Channel Unit
Drawing #
AS/1099
AS/0356
AS/0773-X
AS/0778-X
AS/0365-X
AS/0361
AS/0979-1
AS/0627-2
(Optional)
AS/0569
(Optional)
AS/0627-3
(Optional)
AS/3812
(Optional)
AS/1311-X
(Optional)
Note: X = various options available on the modulator, demodulator, and decoder
boards.
1–4
Rev. 5
SDM-650B Satellite Modem
Introduction
1.3 System Specification
Table 1-1 lists the operating specifications of the modem.
Table 1-1. Operating Specifications
System Specifications
Operating Frequency Range
Type of Modulation
Operating Channel Spacing
BER
Digital Interface
Digital Data Rate:
Variable Rate
Single Rate
Forward Error Correction
Data Scrambling
Diagnostic Features
Prime Power
Size
50 to 90 MHz, or 100 to 180 MHz. Synthesized in
2.5 kHz steps.
QPSK.
BPSK.
Less than 0.5 dB degradation operating with 2 adjacent
like channels each 10 dB higher at 1.3 times the
symbol rate or 75 kHz minimum.
See Table 1-2.
RS-422/-449.
V.35.
DS-1 STD.
G.703.
Others optional.
19.2 to 3584 kbit/s configurable. Choice of up to four
pre-defined rates, or variable rate option.
19.2 to 48 kbit/s, 1/2 rate BPSK only.
19.2 to 2048 kbit/s.
19.2 to 3584 kbit/s.
2048 kbit/s maximum for 1/2 rate.
3072 kbit/s maximum for 3/4 rate.
3584 kbit/s maximum for 7/8 rate.
Convolutional encoding with soft decision, sequential,
or K=7 Viterbi decoding.
Selectable.
CCITT V.35.
None.
RF Loopback.
IF Loopback.
Digital Data Loopback.
Fault Monitoring.
BER Monitoring.
Remote Control via Serial Port.
90 to 132 VAC, or 180 to 264 VAC, 47 to 63 Hz.
75W maximum, fused at 2A.
-48 VDC optional.
5.25” x 19.0” x 18.0” (3RU).
Additional Modulator Specifications
-5 to -30 dBm, adjustable in 0.5 dB steps.
+5 to -15 dBm with high power option.
Output Spurious and Harmonics
-50 dBc in-band (50 to 90 MHz, or 100 to 180 MHz).
-40 dBc out-of-band.
Output Impedance
75Ω.
Output Return Loss
20 dB.
Output Frequency Stability
± 10 PPM.
Data Clock Source
Internal or External.
Internal Data Clock Stability
± 50 PPM.
Output Power
Rev. 5
1–5
Introduction
SDM-650B Satellite Modem
Additional Demodulator Specifications
Input Power:
Desired Carrier
Composite
Input Impedance
Input Return Loss
Carrier Acquisition Range
Clock Acquisition Range
-30 to -55 dBm.
+30 dB power within 20 MHz from desired carrier.
+40 dB power outside of 20 MHz from desired
carrier.
0 dBm maximum composite.
75Ω.
20 dB.
± 25 kHz minimum.
± 100 PPM.
Remote Control Specifications
RS-232-C, or RS-485.
300 to 9600 bit/s.
Transmit Frequency.
Receive Frequency
Transmit Power.
Transmitter ON/OFF.
Data Rate Select.
RF Loopback.
IF Loopback.
Data Loopback.
Scrambler ON/OFF.
Descrambler ON/OFF.
Raw Error Rate.
Corrected BER.
Receive Eb/N0.
TX Clock Internal/External.
RX Clock Normal/Invert.
Receive Signal Level.
Receive Carrier Detect.
Power Supply Voltages.
Stored Fault Status.
Configuration Retention
Will maintain current configuration for 30 days
minimum without power.
Addressing
Programmable to 1 of 255 possibilities. Address 0
reserved for global addressing.
Local control of all remote functions included via push-button entry.
Serial Interface
Baud Rate
Signals Controlled/Monitored
1–6
Rev. 5
SDM-650B Satellite Modem
Introduction
The specifications for the Bit Energy-to-Noise Ratio (Eb/N0) required to achieve 10-5 and
10-7 BER for different coding configurations is listed in Table 1-2. All values are for
operation in QPSK mode.
Table 1-2. BER Performance Specifications
Data Rate
1/2 Rate
100 kbit/s
BER 10-5
BER 10-7
1544 kbit/s
BER 10-5
BER 10-7
Sequential
3/4 rate
7/8 Rate
Viterbi K=7
1/2 Rate
4.8 dB
5.8 dB
5.8 dB
6.6 dB
6.7 dB
8.0 dB
5.5 dB
6.7 dB
5.8 dB
6.6 dB
6.3 dB
7.1 dB
6.9 dB
8.0 dB
5.5 dB
6.7 dB
Without coding, the modem provides operation within 0.5 dB of theoretical for BPSK,
and within 0.8 dB for QPSK.
Performance measurements are with transmit, and receive IF connected back-to-back
through an additive white Gaussian noise channel.
BER performances of the modem are shown in Figures 1-4 through 1-7.
A typical output spectrum of the modem is shown in Figure 1-8.
Rev. 5
1–7
Introduction
SDM-650B Satellite Modem
10-2
10-3
10-4
10-5
10-6
BER
10-7
10-8
100 kbit/s
1544 kbit/s
SPECIFICATIONS
10-9
10-10
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
Eb/N0 (dB)
Figure 1-4. Sequential Decoder BER Performance Curves (1/2 Rate)
1–8
Rev. 5
SDM-650B Satellite Modem
Introduction
10-2
10-3
10-4
10-5
10-6
BER
10-7
10-8
100 kbit/s
1544 kbit/s
SPECIFICATIONS
10-9
10-10
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
Eb/N0 (dB)
Figure 1-5. Sequential Decoder BER Performance Curves (3/4 Rate)
Rev. 5
1–9
Introduction
SDM-650B Satellite Modem
10-2
10-3
10-4
10-5
10-6
BER
1544 kbit/s
100 kbit/s
10-7
SPECIFICATIONS
10-8
10-9
10-10
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
Eb/N0 (dB)
Figure 1-6. Sequential Decoder BER Performance Curves (7/8 Rate)
1–10
Rev. 5
SDM-650B Satellite Modem
Introduction
10-2
10-3
10-4
10-5
10-6
BER
10-7
100 kbit/s
or
1544 kbit/s
10-8
SPECIFICATIONS
10-9
10-10
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
Eb/N0 (dB)
Figure 1-7. Viterbi Decoder BER Performance Curves (1/2 Rate)
Rev. 5
1–11
Introduction
SDM-650B Satellite Modem
Figure 1-8. SDM-650B Typical Output Spectrum
1–12
Rev. 5
Chapter 2.
INSTALLATION
This chapter provides the following information:
•
•
•
•
Unpacking instructions
External connections
System requirements
System installation
2.1 Unpacking
The modem and manual are packaged in pre-formed, reusable, cardboard cartons
containing foam spacing for maximum shipping protection. The three main circuit boards
are packed in separate cardboard caddypacks (included within the cardboard carton).
To remove the modem:
Do not use any cutting tool that will extend more than 1” into the container
and cause damage to the modem.
CAUTION
Parts and assemblies may be damaged by Electrostatic Discharge (ESD).
ESD safety precautions should always be observed when handling parts.
1. Cut the tape at the top of the carton (indicated by OPEN THIS END).
2. Remove the cardboard/foam space covering the modem and caddypacks.
3. Remove the modem, caddypacks, manual, and power cord from the carton.
Rev. 5
2–1
Installation
SDM-650B Satellite Modem
4. Save the packing material for storage or reshipment purposes.
5. Inspect the equipment for any possible damage incurred during shipment.
6. Check the equipment against the packing list to ensure the shipment is complete.
7. Refer to Section 2.4 for further system installation instructions.
2.2 External Connections
Connections between the modem and other equipment are made through six connectors.
These connectors are listed in Table 2-1 and their locations are shown in Figure 2-1.
DATA
GROUND
ERDE
I/OI
TX/IF
OUTPUT
CP1
REMOTE
J6
J8
FAULT
MADE IN USA
J7
RX/IF
INPUT
CP2
Figure 2-1. SDM-650B Rear Panel View
Table 2-1. Rear Panel Connectors
Name
DATA I/O
Ref. Design.
J8
Connector Type
Various
REMOTE
FAULT
IF OUTPUT
IF INPUT
AC POWER
GROUND
J6
J7
CP1
CP2
None
GROUND
9-Pin D
9-Pin D
BNC
BNC
Standard
#10-32 Stud
Function
RS-422/MIL-STD-188 I/O
V.35 DATA I/O
DS1 DATA I/O
G.703 DATA I/O
Asynchronous Overhead
Channel Unit
Interface
FORM C Fault Relay Contacts
TX IF Output
RX IF Input
AC Power Input
Chassis Ground
The use of each connector is described in the following paragraphs.
2–2
Rev. 5
SDM-650B Satellite Modem
Installation
2.2.1 DATA I/O
For information and pinouts on the data connectors, refer to Chapter 3.
2.2.2 Remote (J6)
The remote connector on the modem is used to interface the Monitor and Control (M&C)
functions to a remote location. This interface can be either RS-232-C or RS-485. For a
complete discussion on the remote interface, refer to Chapter 3.
The remote interface is provided on a 9-pin female D connector. Screw locks are
provided for mechanical security of the mating connector. The remote connector is a Data
Circuit Terminating Equipment (DCE) interface.
RS-485
Pin #
Name
1
GND
2
3
4
+RX/TX
5
-RX/TX
6
7
8
+RX/TX
9
-RX/TX
RS-232-C
Pin #
Name
1
2
RD (RX)
3
TD (TX)
4
5
GND
6
DSR
7
RTS
8
CTS
9
2.2.3 Fault (J7)
The fault connector on the modem is used to provide FORM C contact closures for the
purpose of fault reporting.
There are three FORM C summary fault contacts:
•
•
•
Modulator
Demodulator
Common equipment
Refer to Chapter 4 for a complete discussion on monitored faults.
To obtain a system summary alarm, connect all FORM C contacts in parallel.
Rev. 5
2–3
Installation
SDM-650B Satellite Modem
The fault interface is provided on a 9-pin female D connector. Screw locks are provided
for mechanical security on the mating connector.
Pin #
1
2
3
4
5
6
7
8
9
Name
NO
COM
NC
NO
COM
NC
NO
COM
NC
Function
Common equipment is OK
Common equipment is faulted
Modulator is OK
Modulator is faulted
Demodulator is OK
Demodulator is faulted
Note: A connection between the common (COM) and normally open (NO) contacts
indicates no fault.
2.2.4 IF Output (CP1)
This is the transmit IF connector. The output impedance is 75Ω, and the output power
level is -5 to -30 dBm.
In normal operation, the output will be a QPSK-modulated result of the DATA I/O
connector, with a frequency between 50 and 90 MHz, or 100 and 180 MHz.
2.2.5 IF Input (CP2)
This is the receive IF connector. The input impedance is 75Ω.
For normal operation, the signal level needs to be between -30 dBm and -55 dBm, with a
maximum composite level of 0 dBm. Signals between 50 and 90 MHz, or 100 and 180
MHz, are selected and demodulated to produce clock and data at the DATA I/O
connector.
2.2.6 AC Power
The AC power is supplied to the modem by a standard detachable, non-locking, 3-prong
power cord.
Normal input voltage is 90 to 132 VAC, or 180 to 264 VAC, 47 to 63 Hz. Maximum
power consumption is less than 75W.
CAUTION
2–4
Damage may result if the incorrect input voltage is applied to this connector.
If there is any question of voltage compatibility, do not connect the unit until
EFData has been contacted.
Rev. 5
SDM-650B Satellite Modem
Installation
2.2.7 GROUND
A #10-32 stud is available on the rear panel for the purpose of connecting a common
chassis ground between all of the equipment.
2.3 System Requirements
The standard modem with all cards installed (as listed in Chapter 1) is a full-duplex
QPSK satellite modem.
The system can also be configured for TX-only or RX-only operation:
•
For a TX-only system, the demodulator (AS/0778-X) and decoder (AS/0365-X)
are removed. The Utility menu on the front panel must be entered and Operation
mode selected. Enter the menu and select TX-only. This will mask the receive
faults and receive stored faults in the Faults menu.
•
For an RX-only system, the modulator (AS/0773-X) is removed. Enter the Utility
menu on the front panel and select Operation mode. Enter the menu and select
RX-only. This will mask the transmit faults and transmit stored faults in the
Faults menu.
The modem interface is configured by the selection of the data interface card. Refer to
Chapter 3 for discussion on the data interface cards.
The modem data/code rate is configured by the installation of a daughter card (AS/0363,
AS/0715, or AS/0930-1) on the modulator, and a daughter card (AS/0362, or
AS/0929-X) on the demodulator. The Utilities function must be set up to be compatible
with the daughter cards. Refer to Chapter 4 for information on the Utilities function. The
modem will be set up to match the daughter cards when it is shipped from the factory.
Rev. 5
2–5
Installation
SDM-650B Satellite Modem
2.4 System Installation
After unpacking, install the modem as follows:
1. Mount the modem chassis in its assigned position in the equipment rack.
2. Connect the cables to the rear panel in the appropriate locations. Refer to
Section 2.2 for connector pinouts, placement, and functions.
3. Open the front panel and verify the three main cards, the M&C, and data
interface cards are properly seated.
Refer to Figure 1-3 for proper positioning of the cards.
When the cards are installed correctly, the color of the card guides on the chassis
will match the color of the card ejectors on the cards.
4. Before turning ON the power switch, read and become familiar with the
information in Chapter 4.
5. Turn ON the power switch (located inside the front panel).
6. Check for proper TX signal level and spectrum.
7. Check for proper RX signal level and spectrum.
8. If there is any problem with the installation, refer to Chapter 6 for
troubleshooting information.
2–6
Rev. 5
Chapter 3.
CONFIGURATION
This chapter provides the following information:
•
•
•
•
•
•
Monitor and control
Digital interfaces
Doppler buffer assembly
Doppler buffer specification
I/O connectors
Interface clocking options
3.1 Monitor and Control
The modem uses a sophisticated microcontroller module to perform the M&C functions
of the modem (refer to Figure 3-1).
The M&C monitors the modem, and provides configuration updates to other modules
within the modem when necessary.
Modem configuration parameters are maintained in battery-backed RAM, which provides
for total recovery after a power-down situation.
Extensive fault monitoring and status gathering are provided.
All modem functions are accessible through a local front panel interface and a remote
communications interface.
Rev. 5
3–1
Configuration
SDM-650B Satellite Modem
Figure 3-1. M&C Card
3.1.1 Description of Options
3.1.1.1 Remote Interface
All modem functions can be remotely controlled and monitored via an RS-485 (optional
RS-232-C) communications link.
•
The 2-wire, half-duplex RS-485 interface makes it possible to operate
255 modems on a common communications link.
•
The RS-232-C interface is used to communicate with a single modem.
The M&C module must be hardware configured to one of the two interfaces.
Perform the following steps to configure the M&C for RS-485 operation:
1. Remove jumpers JP4, JP5, and JPX.
2. Install jumpers JP1, JP2, and JP3.
3. Connect JP7 to RS-485.
Perform the following steps to configure the M&C for RS-232-C operation:
1. Remove jumpers JP1, JP2, and JP3.
2. Install jumpers JP4, JP5, and JPX.
3. Connect JP7 to RS-232-C.
3–2
Rev. 5
SDM-650B Satellite Modem
Configuration
3.1.1.2 Remote Baud Rate
The remote communications baud rate and parity are programmed by a switch pack (SP1)
on the M&C module.
Programming the baud rate and parity is accomplished by setting the appropriate switches
in the OFF or ON positions:
•
A switch is programmed OFF by placing it in the position furthest away from the
PCB (open).
•
A switch is programmed ON by placing it in the position nearest the PCB.
Switch position #1 sets the parity as follows:
Even Parity
Odd Parity
SP1-1
SP1-1
OFF
ON
Switch positions #2, #3, and #4 set the baud rate as follows:
Baud
110
150
300
600
1200
2400
4800
9600
SP1-2
ON
ON
ON
ON
OFF
OFF
OFF
OFF
SP1-3
ON
ON
OFF
OFF
ON
ON
OFF
OFF
SP1-4
ON
OFF
ON
OFF
ON
OFF
ON
OFF
Note: SP1 on the M&C modules has four additional switches (SP1-5 through SP1-8).
These four switch locations are not currently assigned or used.
Rev. 5
3–3
Configuration
SDM-650B Satellite Modem
3.1.1.3 Remote Address
Each modem must be configured for a distinct address between 1 and 255 to
communicate using the established remote communications protocol.
Addresses are programmed by a switch pack (SP2) on the M&C module.
Addresses are binary coded numbers set at SP2. Switch #1 (SP2-1) is the most significant
bit, and switch #8 (SP2-8) is the least significant bit.
3.1.1.4 Battery
A rechargeable battery on the M&C module allows the modem to retain configuration
information without prime power for up to 30 days. A jumper (JP6) is supplied on the
M&C module to disconnect battery power from the backup RAM. During normal
operation, this jumper should be in the ON position. Should the modem be powereddown, the following sequence is carried out by the M&C microcontroller:
1. When power is applied to the M&C, the microcontroller checks the batterybacked RAM to see if valid data has been retained. If valid data has been
retained, the modem is reconfigured to the configuration maintained in RAM.
2. If the battery-backed RAM failed the valid data test, the modulator, demodulator,
and interface modules would be tested to determine if valid configuration
information was retained by them. If valid configuration information was
retained by a module, that module’s configuration will be stored in the
battery-backed RAM and maintained.
3. If battery-backed RAM and a module failed the valid data test, a default
configuration for the module from ROM is stored in battery-backed RAM and
maintained.
To erase the configuration stored in RAM, capacitor C12 must be shorted while JP6 is
OFF.
3–4
Rev. 5
SDM-650B Satellite Modem
Configuration
3.1.1.5 Modulator/Coder Defaults
TXA
TXB
TXC
TXD
TXR
TX-FREQ
RF-OUT
TX-POWER
RFLOOPBK
IFLOOPBK
BBLOOPBK
SCRAMBLR
DIFENCDR
TX-CLOCK
SWP-RACQ
SWP-CNTR
SWP-RNGE
SWP-DIR
CW-MODE
Transmit Filter A — 7/8 code rate, 56 kbit/s
Transmit Filter B — 3/4 code rate, 56 kbit/s
Transmit Filter C — 1/2 code rate, 56 kbit/s
Transmit Filter D — 1/2 code rate, 64 kbit/s
Transmit Rate Selected — A 7/8, 56 kbit/s
Transmitter Frequency — 70 MHz
RF Output — OFF
Transmit Power Level — -10 dBm
RF Loopback — OFF
IF Loopback — OFF
Baseband Loopback — OFF
Scrambler — ON
Differential Encoder — ON
Transmit Clock — Internal
Sweep Re-acquisition — 0 Sec
Sweep Center — Hz
Sweep Range — 5000 Hz
Sweep Direction — Forward
Continuous Wave Mode — OFF
(See Note Below)
(See Note Below)
(See Note Below)
Note: These windows will only be displayed when FAST-ACQ (Fast Acquisition)
has been turned ON in the Utility menu.
3.1.1.6 Demodulator/Decoder Defaults
RXA
RXB
RXC
RXD
RXR
RX-FREQ
RFLOOPBK
BBLOOPBK
DSCRMBLR
RX-CLOCK
BERTHSLD
Receive Filter A — 7/8 decode rate, 56 kbit/s
Receive Filter B — 3/4 decode rate, 56 kbit/s
Receive Filter C — 1/2 decode rate, 56 kbit/s
Receive Filter D — 1/2 decode rate, 64 kbit/s
Receive Rate Selected — A 7/8, 56 kbit/s
Receiver Frequency — 70 MHz
RF Loopback — OFF
Base Band Loopback — OFF
Descrambler — ON
Receive Clock — Normal
BER Threshold [None]
3.1.1.7 Utility Defaults
DATE
TIME
POW-ADJ
OP-MODE
FAST-ACQ
Rev. 5
7/4/76
12:00 AM
-5 dB
Duplex
OFF
3–5
Configuration
SDM-650B Satellite Modem
3.1.2 Remote Interface Specification
Refer to Appendix B for remote control operation information.
3.1.3 M&C Theory of Operation
The M&C module is built around the Intel 80C31 microcontroller operating at
5.5295 MHz. The microsystem is designed to support:
•
•
64K bytes of read-only code memory
64K bytes of random access data memory
Of the 64K bytes data memory, only 4K is used for RAM. The remaining address is used
for memory-mapped I/O. Memory-mapped I/O includes:
•
•
•
Real time clock/memory
8-channel analog-to-digital converter
External buffered bus structure for overall modem control and status gathering
The 80C31 microcontroller supports a serial asynchronous communications channel with
a maximum baud rate of 9600 bit/s using the 5.5295 MHz reference.
A rechargeable battery is employed to maintain the system real time clock and modem
configuration through power-out situations.
3–6
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2 Digital Interfaces
3.2.1 RS-422 and MIL-STD-188-114 Interface
3.2.1.1 Functional Description
The RS-422 and MIL-STD-188-114 digital interface (Figure 3-2) provides the level
translation, buffering, and termination between the internal modem signals and the
RS-422 or MIL-STD-188-114 interface connector on the rear panel. A functional block
diagram of the interface is shown in Figure 3-3.
ADDRESSING SELECT JUMPERS
JP1
JP9
JP16
RS-422/MIL-188
ADAPTOR CONNECTOR
RS 422
JP3
JP8
JP10
JP2
JP13
JP12
JP15
JP14
ASSEMBLY AND
REVISION NUMBER
Figure 3-2. RS-422 and MIL-STD-188-114 Interface Board
Rev. 5
3–7
Configuration
SDM-650B Satellite Modem
Electrical characteristics of the RS-422 interface signals are defined in EIA-STD-RS-422.
Electrical characteristics of the MIL-STD-188-114 interface signals are defined in
MIL-STD-188-114 and MIL-STD-188-100.
•
EIA-STD-RS-449 provides details of the mechanical interface.
•
MIL-STD-188-114 defines signal levels, offsets, termination resistors, etc.
•
MIL-STD-188-100 specifies such characteristics as signal quality and clock/data
phase relationships.
TO BUFFER
OPTIONS
LOOP TIMING
TO LOGIC CONTROL
JP12
SCT
INT/EXT CLOCK
TO CONTROL LOGIC
LOOPBACK
TO CONTROL LOGIC
ST
TT
JP1
RT
TX CLOCK
M
O
D
E
M
JP2
AUTO
CLOCK
SELECT
SD
RD
TX DATA
JP8
RX CLOCK
INVERT
NORM
JP3
RX DATA
EXTERNAL BUFFER CLOCK
TO BUFFER
OPTIONS
MC
CS
JP9
COMMON EQUIPMENT
RS
FAULT
MODULATOR
RELAYS
CONTROL
LOGIC
RTS TO CTS JUMPER
T
E
R
R
E
S
T
R
I
A
L
SPARE (RS-232 ONLY)
DEMODULATOR
TTL MODULATOR FAULT
DATA BUS TO M & C
TTL DEMODULATOR FAULT
Figure 3-3. RS-422 and MIL-STD-188-114 Block Diagram
3–8
Rev. 5
SDM-650B Satellite Modem
Configuration
The RS-422 and MIL-STD-188-114 interface provides a Send Timing (ST) clock signal
at the modem data rate.
In the Internal Clock mode, the data to be transmitted, Send Data (SD), must be
synchronized to ST. In the External Clock mode, the clock is accepted on the Terminal
Timing (TT) input to clock in the data to be transmitted. In either case, the phase
relationship between the clock and data is not important as long as relationship meets the
jitter specifications of RS-422 or MIL-STD-188-100.
A clock phase correction circuit is provided which shifts the clock away from the data
transition times. The clock phasing is jumper-selectable at JP1.
When there is no jitter on the clock source, the Auto setting is used.
The Normal setting is used when standard specifications on clock and data relationships
exist. The Invert mode is used when the incoming clock is inverted from the standard
clock and data relationship.
Data received by the modem is output on the Receive Data (RD) lines.
Recovered clock is output on the Receive Timing (RT) lines.
For applications that require the rising edge of the clock to occur in the middle of the data
bit time, Receive Clock Normal mode should be selected.
Invert mode puts the falling edge of RT in the middle of the data bit. This selection can
be made from the front panel in the Configuration menu.
The Request to Send (RTS) lines are hard-wired to the Clear to Send (CTS) lines, since
the modem does not support polled operation.
Data Mode (DM) indicates that the modem is powered-up.
Receive Ready (RR) indicates that an RF carrier is being received and demodulated with
a sufficiently low error rate for the decoder to remain locked.
The RS-422 and MIL-STD-188-114 interface also provides bi-directional relay loopback
of both the clock and data at the DCE interface. In Loopback:
Rev. 5
•
From the DTE side, SD is connected to RD, and either ST or TT (in Internal or
External mode) is looped back to RT.
•
From the modem side, the received data and recovered clock are routed back to
the modulator input for re-transmission.
3–9
Configuration
SDM-650B Satellite Modem
Loop timing is supported by the selection of jumper JP10. When in the ON position, the
transmit clock (ST) is replaced by the clock recovered from the satellite (RT). Active
loop timing is indicated by a yellow light on the front edge of the card. The JP10 REM
setting is for future options.
Three fault outputs are provided on dry contact FORM C relays:
•
•
•
Common Equipment
Modulator
Demodulator
The faults are available on the fault connector on the modem rear panel. Generation of
these fault conditions is described in Chapter 4. Fault indicators are also provided on
TTL open collector drivers on the RS-422 or MIL-STD-188-114 connector.
The TTL MOD fault indicates a Modulator fault or Common Equipment fault.
The TTL DEMOD fault indicates a Demodulator or Common Equipment fault.
The PCB for the RS-422/MIL-STD-188-114 interface is used for a number of different
interface types. The differences are jumper settings on the board, and hardware
configuration. Different parts will be installed for the various configurations. Changing to
a different interface can be done by replacing the board.
Table 3-1 describes the jumper settings for a Rev. E board.
3–10
Rev. 5
SDM-650B Satellite Modem
Configuration
Table 3-1. AS/0627-3 Rev. E Board Jumper Selection
JP1
TX Clock Select
JP2
Interface Select
JP3
RX Data
JP8
RX Clock
JP4
JP5
JP6
JP7
Address Set
Address Set
Address Set
Address Set
JP9
CTS to RTS
JP10
Loop Timing
JP11
JP12
ASYNC Clk Syn (-5)
SCT
JP13
RD
JP14
RR
JP15
DM
JP16
SD
Normal
Invert
Auto
V.35 (-2)
MIL-STD-188/RS-232-C (-3)
Normal
Buffer
Normal
Buffer
0
0
1
1
MIL (-3)
V.35 (Processor controller for
V.35 and RS-232-C)
MIL-STD-188/RS-422
(Hard loops CTS to RTS)
REM
ON
OFF
Cut Shorts
1 to 2 Invert
2 to 3 Normal
1 to 2 Invert
2 to 3 Normal
1 to 2 Invert
2 to 3 Normal
1 to 2 Invert
2 to 3 Normal
1 to 2 Invert
2 to 3 Normal
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
(See Note Below)
Note: Factory jumper settings for MIL-STD-188/RS-422 interface type.
These jumpers are factory set for each given configuration, and should not be changed.
This list is supplied for troubleshooting purposes only.
Rev. 5
3–11
Configuration
SDM-650B Satellite Modem
3.2.1.2 Connector Pinouts
The RS-422 and MIL-STD-188-114 interface is provided on a 37-pin female D
connector, accessible from the rear panel of the modem. Screw locks are provided for
mechanical security of the mating connector.
Signal Function
SIGNAL GROUND
SEND DATA
SEND TIMING
RECEIVE DATA
REQUEST TO SEND
RECEIVER TIMING
CLEAR TO SEND
DATA MODE
RECEIVER READY
TERMINAL TIMING
MOD FAULT
DEMOD FAULT
MASTER CLOCK
(INPUT)
3–12
Name
SG
SD-A
SD-B
ST-A
ST-B
RD-A
RD-B
RS-A
RS-B
RT-A
RT-B
CS-A
CS-B
DM-A
DM-B
RR-A
RR-B
TT-A
TT-B
−
−
MC-A
MC-B
Pin #
1, 19, 20, 37
4
22
5
23
6
24
7
25
8
26
9
27
11
29
13
31
17
35
3
21
16
34
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2.1.3 Specification
Circuit Supported
Amplitude (RD, RT, ST, DM, RR)
DC Offset (RD, RT, ST, DM, RR)
Impedance (RD, RT, ST, DM, RR)
Impedance (SD, TT, MC)
Polarity
Phasing (RD, RT)
Symmetry (ST, TT, RT)
Frequency Stability (ST)
Modulator Fault
Demodulator Fault
Rev. 5
SD, ST, TT, RD, RT, DM, RR, MOD, FAULT,
DEMOD FAULT, MC.
4, ± 2V differential into 100Ω.
0, ± 0.4V.
Less than 100Ω, differential.
100, ± 20Ω, differential.
True when B positive wrt A.
False when A positive wrt B.
False to True transition of RT nominally in
center of RD data bit.
50%, ± 5%.
± 100 PPM.
Open collector output.
15V max.
20 mA max. current sink.
Fault is open circuit.
Open collector output.
15V max.
20 mA max. current sink.
Fault is open circuit.
3–13
Configuration
SDM-650B Satellite Modem
3.2.2 V.35 Interface
3.2.2.1 Functional Description
The V.35 digital interface (Figure 3-4) provides level translation, buffering, and
termination between the internal modem signals and the V.35 DCE interface connector
on the rear panel.
Electrical characteristics of the interface signals are defined in CCITT Recommendation
V.35.
The electrical and mechanical specifications are summarized in Section 3.2.2.2 and
Section 3.2.2.3, respectively.
A functional block diagram of the V.35 interface is shown in Figure 3-5.
The V.35 interface provides a Serial Clock Transmit (SCT) clock signal at the modem
data rate.
In the Internal clock mode, the data to be transmitted, SD, must be synchronized to SCT.
In the External clock mode, the clock is accepted on the Serial Clock Transmit External
(SCTE) input to clock in the data to be transmitted.
ADDRESS SELECT JUMPERS
JP1
JP16
JP3
JP8
JP10
JP2
JP13
JP12
JP15
JP14
ASSEMBLY NUMBER
AND REVISION
V.35 ADAPTOR
CONNECTOR
Figure 3-4. V.35 Interface Card
3–14
Rev. 5
SDM-650B Satellite Modem
Configuration
TO BUFFER
OPTIONS
LOOP TIMING
TO LOGIC CONTROL
SCT
INT/EXT CLOCK
TO CONTROL LOGIC
ST
LOOPBACK
TO CONTROL LOGIC
TT
RT
TX CLOCK
M
O
D
E
M
AUTO
CLOCK
SELECT
SD
RD
TX DATA
RX CLOCK
INVERT
NORM
RX DATA
EXTERNAL BUFFER CLOCK
TO BUFFER
OPTIONS
MC
CS
COMMON EQUIPMENT
RS
FAULT
MODULATOR
RELAYS
CONTROL
LOGIC
RTS TO CTS JUMPER
T
E
R
R
E
S
T
R
I
A
L
SPARE (RS-232 ONLY)
DEMODULATOR
TTL MODULATOR FAULT
DATA BUS TO M & C
TTL DEMODULATOR FAULT
Figure 3-5. V.35 Interface Block Diagram
In either case, the phase relationship between the clock and data is not important as long
as the relationship meets the jitter specification. This is because a clock phase correction
circuit is provided, which shifts the clock away from the data transition times.
The clock selection is jumper-selectable at JP1 on the front edge of the board.
Rev. 5
•
When there is no jitter on the clock source, the Auto setting is used.
•
The Normal setting is used when standard specifications on clock and data
relationships exist.
•
The Invert mode is used when the incoming clock is inverted from the standard
clock and data relationship.
3–15
Configuration
SDM-650B Satellite Modem
Data received by the modem is output on the RD lines, while the recovered clock is
output on the Serial Clock Receive (SCR) lines. For applications that require the rising
edge of the clock to occur in the middle of the data bit time, Receive Clock Normal mode
should be selected.
Invert mode puts the falling edge of SCR in the middle of the data bit. This selection can
be made from the front panel in the Configuration menu.
The RTS lines are jumpered to the CTS lines, since the modem does not support polled
operation. Data Set Ready (DSR) indicates that the modem is powered up. Receive Line
Signal Detect (RLSD) indicates that an RF carrier is being received and demodulated
with a sufficiently low error rate for the decoder to remain locked.
The V.35 interface also provides bi-directional relay loopback of both the clock and data
at the DCE interface.
In loopback from the DTE side, SD is connected to RD, and either SCT or SCTE (in
Internal or External mode) is looped back to SCR.
In loopback from the modem side, the received data and recovered clock are routed back
to the modulator input for re-transmission.
Loop timing is supported by the selection of jumper JP10 on the front edge of the card.
When in the ON position, the internal clock (SCT) is replaced by the clock recovered
from the receive (IF) data (RD). Active loop timing is indicated by a yellow light on the
front edge of the card.
The JP10 REM setting is used when loop timing is supported by software on the M&C,
and will be included in the front panel menu.
Three fault outputs are provided on dry contact FORM C relays:
•
•
•
Common Equipment
Modulator
Demodulator
The faults are available on the Fault connector on the modem rear panel. Generation of
these fault conditions is described in Chapter 4. Fault indicators are also provided on TTL
open collector drivers on the V.35 connector.
•
•
3–16
The TTL MOD fault indicates a Modulator fault or Common Equipment fault.
The TTL DEMOD fault indicates a Demodulator or Common Equipment fault.
Rev. 5
SDM-650B Satellite Modem
Configuration
Table 3-2 lists the jumper settings for the V.35 interface. These jumpers are factory set
for a specific configuration. Clock selections, signal selections, and loop timing can be
changed upon individual needs.
Table 3-2. AS/0627-2 Rev. E Board Jumper Selection
JP1
TX Clock Select
JP2
JP3
Interface Select
RX Data
JP8
RX Clock
JP4
JP5
JP6
JP7
Address Set
Address Set
Address Set
Address Set
JP9
CTS to RTS
JP10
Loop Timing
JP11
JP12
ASYNC Clk Syn (-5)
SCT
JP13
RD
JP14
RR
JP15
DM
JP16
SD
Normal
Invert
Auto
(See Note Below)
V.35 (-2)
(See Note Below)
Normal
(See Note Below)
Buffer
Normal
(See Note Below)
Buffer
1
(See Note Below)
0
(See Note Below)
1
(See Note Below)
1
(See Note Below)
V.35 (-2)
V.35
(See Note Below)
(Processor controller for V.35 and RS-232-C)
Auto
ON
OFF
(See Note Below)
Cut Shorts
1 to 2 Invert
2 to 3 Normal
(See Note Below)
1 to 2 Invert
2 to 3 Normal
(See Note Below)
1 to 2 Invert
2 to 3 Normal
(See Note Below)
1 to 2 Invert
2 to 3 Normal
(See Note Below)
1 to 2 Invert
2 to 3 Normal
(See Note Below)
Note: Factory jumper settings for V.35 interface type.
Rev. 5
3–17
Configuration
SDM-650B Satellite Modem
3.2.2.2 Connector Pinouts
The V.35 interface is provided on the industry standard 34-pin block connector accessible
from the rear panel of the modem. Screw locks are provided for mechanical security of
the mating connector.
Signal Function
SIGNAL GROUND
SEND DATA
SERIAL CLOCK TRANSMIT
RECEIVE DATA
REQUEST TO SEND
SERIAL CLOCK RECEIVE
CLEAR TO SEND
DATA SET READY
RECEIVE LINE SIGNAL DETECT
SERIAL CLOCK TRANSMIT EXT
MODULATOR FAULT
DEMODULATOR FAULT
MASTER CLOCK
(INPUT)
3–18
Name
SG
SD-A
SD-B
SCT-A
SCT-B
RD-A
RD-B
RTS
SCR-A
SCR-B
CTS
DSR
RLSD
SCTE-A
SCTE-B
−
−
MC-A
MC-B
Pin #
A, B
P
S
Y
(AA)
R
T
C
V
X
D
E
F
U
W
(MM) m
(NN) n
(CC) c
(DD) d
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2.2.3 Specification
Circuit Supported
Amplitude (RD, SCR, SCT, SD, SCTE)
Amplitude (CTS, DSR, RLSD)
Impedance (RD, SCR, SCT)
Impedance (SD, SCTE)
Impedance (RTS)
DC Offset (RD, SCR, SCT)
Polarity (SD, SCT, SCTE, RD, SCR)
Polarity (RTS, CTS, DSR, RLSD)
Phasing (SCTE, SCR)
Symmetry (SCT, SCTE, SCR)
Frequency Stability (SCT)
Modulator Fault
Demodulator Fault
Rev. 5
SD, SCT, SCTE, RD, SCR, DSR, RLSD, MOD,
FAULT, DEMOD FAULT, MC.
0.55V pk, ± 20% differential, into 100Ω.
10, ± 5V into 5000, ± 2000Ω.
100, ± 20Ω, differential.
100, ± 10Ω, differential.
5000, ± 2000Ω, < 2500 pF.
± 0.6V max., 1000Ω termination to ground.
True when B positive wrt A.
False when A positive wrt B.
True when < -3V wrt ground.
False when > +3V wrt ground.
False to True transition nominally in center of data
bit.
50%, ± 5%.
± 100 PPM.
Open collector output.
15V max.
20 mA current sink max.
Fault is open circuit.
Open collector output.
15V max.
20 mA current sink max.
Fault is open circuit.
3–19
Configuration
SDM-650B Satellite Modem
3.2.3 DS-1 Interface
3.2.3.1 Functional Description
The DS-1 digital interface (Figure 3-6) provides level translation, buffering, and
termination between the internal modem signals and the DS-1 DTE interface on the rear
panel.
SWITCH 1
Figure 3-6. DS-1 Interface Card
The DS-1 standard is defined in Bell System Publication 62411.
Refer to Figure 3-7 for a functional block diagram of the DS-1 interface.
The DS-1 is a single data rate interface. The interface operates at 1.544 Mbit/s, normally
referred to as the “T1” rate. This interface is also unique in that no clock signals are
provided.
The clock information is provided in the data signal through the data encoding method
used, Alternate Mark Invert (AMI). In this method, a mark is transmitted as a positive or
negative pulse, one-half the width of the data-bit time. Each consecutive mark has the
opposite sign of its predecessor. Spaces are transmitted as an all-zero voltage.
In order to provide a clear channel (i.e., a channel in which an indefinite number of 0s
can be transmitted), B8ZS encoding and decoding are provided. This allows the modem
to interface with DTE utilizing B8ZS coding. B8ZS coding is enabled by an on-board
jumper (SW1-1). SW1-1 in the open position enables the B8ZS encoder and decoder.
SW-1 in the closed position disables the B8ZS encoder and decoder, and the DS1
interface will operate in AMI.
3–20
Rev. 5
SDM-650B Satellite Modem
Configuration
TO BUFFER
OPTIONS
DS-1 LINE
RECEIVER/DRIVER
TX CLOCK
SD
DS-1
DEJITTER
M
O
D
E
M
TX DATA
RD
LOOPBACK CONTROL
RX CLOCK
RX DATA
EXTERNAL BUFFER CLOCK
TO BUFFER
OPTIONS
COMMON EQUIPMENT
MODULATOR
FAULT
RELAYS
CONTROL
MC
T
E
R
R
E
S
T
R
I
A
L
LOGIC
DEMODULATOR
TTL MODULATOR FAULT
TTL DEMODULATOR FAULT
DATA BUS TO M & C
Figure 3-7. DS-1 Interface Block Diagram
The data to be transmitted by the modem is input on the SD lines. Jitter on the SD is
removed by a FIFO and clock recovery phase-locked loop. Data received and
demodulated by the modem is output on the RD lines.
The RD is driven from a pulse-shaper circuit which pre-equalizes the RD output to drive
up to 655 feet of ABAM cable. Refer to Table 3-3.
The DS-1 interface provides bi-directional loopback of the data at the DCE interface.
In loopback from the DTE side, SD is connected to RD.
In loopback from the modem side, the received demodulated data is routed back to the
modulator input for re-transmission.
Rev. 5
3–21
Configuration
SDM-650B Satellite Modem
Table 3-3. Equalizer Control
Distance to DSX (Ft)
SW1 (See Note 2)
(See Note 1)
(applies only to
22–GA. PIC
[ABAM] Cable)
0 to 133
133 to 267
167 to 400
400 to 533
533 to 655
Test Clear
Maximum Cable
Loss
(dB at 772 kHz)
0.6
1.2
1.8
2.4
3.0
---
4
3
2
EC1
C
C
C
C
O
O
EC2
C
C
O
O
C
C
EC3
C
O
C
O
C
O
Notes:
1. Other bit combinations represent test modes and are not used for normal
operation.
2. Use maximum loss figures for other cable types.
Three fault outputs are provided on dry contact FORM C relays:
•
•
•
Common Equipment
Modulator
Demodulator
The faults are available on the fault connector on the modem rear panel. Generation of
these fault conditions is described in Chapter 4.
Fault indicators are also provided on TTL open collector drivers on the DS-1 connector.
•
•
The TTL MOD fault indicates a Modulator fault or Common Equipment fault.
The TTL DEMOD fault indicates a Demodulator or Common Equipment fault.
In order to facilitate testing of the modem when a DS-1 signal is not available, the output
of the clock recovery circuitry is replaced by a 1.544 MHz clock whenever loss of the SD
signal is detected. This allows the modem to generate its test signals at the proper data
rate.
A TXC-LOSS fault will occur in the Common Equipment fault menu whenever the
incoming data is missing.
3–22
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2.3.2 Connector Pinouts
The DS-1 interface is provided on a 15-pin female D connector accessible from the
modem rear panel. Screw locks are provided for mechanical security of the mating
connector.
Signal Function
SEND DATA
RECEIVE DATA
MASTER CLOCK
MODULATOR FAULT
DEMODULATOR FAULT
GROUND
Name
SD-A
SD-B
RD-A
RD-B
MC-A
MC-B
------GND
Pin #
1
9
3
11
7
8
14
15
2, 4
3.2.3.3 Specification
Circuits Supported
Data Rate
Pulse Width (RD)
Line Code
RD Amplitude
SD Amplitude
Jitter Attenuation (SD)
Modulator Fault
Demodulator Fault
Rev. 5
SD, RD, MOD FAULT, DEMOD FAULT
1.544 Mbit/s ± 100 bit/s
324, ± 50 ns
AMI or B8ZS (selectable)
2.75, ± 0.25V pk into a 100Ω termination
3, ± 1.5V pk into a 100Ω termination
Meets AT&T Publication 62411 specification
Open collector output
15V max
20 mA current sink
Fault is open circuit
Open collector output
15V max
20 mA current sink
Fault is open circuit
3–23
Configuration
SDM-650B Satellite Modem
3.2.4 G.703, 2048 kbit/s Interface
3.2.4.1 Functional Description
The G.703 2048 kbit/s digital interface (Figure 3-8) provides level translation, buffering,
and termination between the internal modem signals and the G.703 DTE interface on the
rear panel.
SWITCH 1
G.703 N X 64KBITS SATELLITE MODEM INTERFACE ASSY/0679 REV-4 FSCN 4J515
Figure 3-8. G.703 2048 kbit/s Interface Card
The G.703 standard is defined in CCITT Volume III (red book).
Refer to Figure 3-9 for a functional block diagram of the G.703 2048 interface.
This interface meets G.703 specifications at 2.048 Mbit/s, normally referred to as the
“E1” rate. This interface is also unique in that no clock signals are provided.
The clock information is provided in the data signal through the data encoding method
used, AMI. In this method, a mark is transmitted as a positive or negative pulse, one-half
the width of the data-bit time. Each consecutive mark has the opposite sign of its
predecessor. Spaces are transmitted as an all-zero voltage.
Refer to Table 3-4 for line code selection and switch settings for the G.703 2048 kbit/s
interface.
In order to provide a clear channel (i.e., a channel in which an indefinite number of 0s
can be transmitted), HDB3 encoding and decoding is provided. This allows the modem to
interface with DTE utilizing HDB3 coding. HDB3 coding is enabled by an on-board
jumper (SW1-7).
3–24
Rev. 5
SDM-650B Satellite Modem
Configuration
N X 64 KB
CLOCK
SYNTHESIZER
TO BUFFER
OPTIONS
TX CLOCK
SD
DS-1
DEJITTER
M
O
D
E
M
TX DATA
DS-1 LINE
RECEIVER/
DRIVER
RD
LOOPBACK CONTROL
RX CLOCK
RX DATA
EXTERNAL BUFFER CLOCK
MC
TO BUFFER
OPTIONS
COMMON EQUIPMENT
FAULT
RELAYS
MODULATOR
CONTROL
T
E
R
R
E
S
T
R
I
A
L
LOGIC
DEMODULATOR
TTL MODULATOR FAULT
TTL DEMODULATOR FAULT
DATA BUS TO M & C
Figure 3-9. G.703 2048 Interface Block Diagram
The G.703 2048 kbit/s interface will operate in AMI, enabled by SW1-8.
The data to be transmitted by the modem is input on the SD lines. Jitter on the SD is
removed by a FIFO and clock recovery phase-locked loop. Data received and
demodulated by the modem is output on the RD lines.
The G.703 2048 kbit/s interface provides bi-directional loopback of the data at the DCE
interface. In loopback from the DTE side, SD is connected to RD. From the modem side,
the received demodulated data is routed back to the modulator input for re-transmission.
Three fault outputs are provided on dry contact FORM C relays:
•
•
•
Rev. 5
Common Equipment
Modulator
Demodulator
3–25
Configuration
SDM-650B Satellite Modem
They are available on the FAULT connector on the modem rear panel. Generation of
these fault conditions is described in Chapter 4.
Table 3-4. G.703, 2048 kbit/s Interface Switch Configurations
1
X
X
0
2
X
X
0
3
X
X
0
SW1 Positions
4
5
6
X
X
X
X
X
X
0
0
1
7
0
1
X
8
0
0
X
Function
Selected
AMI CODE
HDB3
2048 kbit/s
Switch Positions
0
CLOSED
1
OPEN
X
DON’T CARE
Fault indicators are also provided on TTL open-collector drivers on the G.703 2048 kbit/s
connector.
•
•
The TTL MOD fault indicates a Modulator fault or Common Equipment fault.
The TTL DEMOD fault indicates a Demod or Common Equipment fault.
In order to facilitate testing of the modem when a G.703 signal is not available, the output
of the clock recovery circuitry is replaced by a 2.048 MHz clock whenever loss of the SD
signal is detected. This allows the modem to generate test signals at the proper data rate.
3.2.4.2 Optional EXT CLK
This option is used with the Doppler buffer.
The external clock can be used as an optional source of output clock for the optional
Doppler buffer. The two inputs, EXT CLK and /EXT CLK, are capacitively coupled to a
RS−422 receiver and 470Ω resistors to ground. The EXT CLK is normally grounded by
jumper JP17, but may be removed to use RS-422.
In the normal mode, an unbalanced signal should be fed to EXT CLK. The signal may be
sine wave, square wave, or TTL. The signal should be at least 2 Vp-p and have a 40 to
60% duty cycle. Jumpers on the Doppler buffer should be set to select external clock
when this feature is used.
3–26
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2.4.3 Switch Configuration for G.703 2048 kbit/s Interface
Switch 1 is an 8-position dip switch located at the end of the G.703 interface board.
Table 3-4 lists the switch settings for data rates and available coding for the G.703
2048 kbit/s interface.
3.2.4.4 Connector Pinouts
The G.703 2048 kbit/s interface is provided on a 15-pin female D connector accessible
from the rear panel of the modem. Screw locks are provided for mechanical security of
the mating connector.
Signal Function
SEND DATA
RECEIVE DATA
MASTER CLOCK
MODULATOR FAULT
DEMODULATOR FAULT
GROUND
Rev. 5
Name
SD-A
SD-B
RD-A
RD-B
MC-A
MC-B
------GND
Pin #
1
9
3
11
7
8
14
15
2, 4
3–27
Configuration
SDM-650B Satellite Modem
3.2.4.5 G.703 2048 kbit/s Connector Board Option
The G.703 2048 kbit/s interface has a connector board option that is configured with a
15-pin D and three BNCs for unbalanced signals for SD, RD, and MC (Figure 3-10).
Refer to Table 3-5 for jumper connections.
G.703 2048 KBS
CONNECTOR BOARD
SDM 650
AS/1644 REV___
S/N_________
J1
J2
J3
J4
S1
Notes:
1.
2.
J5
Balanced signals are on the 15-pin D connector.
Unbalanced signals are on the BNC connectors.
Figure 3-10. G.703 2048 kbit/s Interface Connector Board (Optional)
3–28
Rev. 5
SDM-650B Satellite Modem
Configuration
Table 3-5. G.703 2048 kbit/s Interface Connector Jumpers
Switch
J3 (EXT REF)
BAL
UNBAL
ON
ON
OFF
OFF
X
X
X
X
X
X
X
X
SW1-1
SW1-2
SW1-3
SW1-4
SW1-5
SW1-6
J4 (SEND DATA)
BAL
UNBAL
X
X
X
X
ON
ON
OFF
OFF
X
X
X
X
J5 (RECEIVE DATA)
BAL
UNBAL
X
X
X
X
X
X
X
X
ON
ON
OFF
OFF
Switch Positions
0
CLOSED
1
OPEN
X
DON’T CARE
The interface connects to the rear of the modem, directly onto the G.703 interface
connector. Refer to Figure 3-11 for a schematic diagram of the optional G.703
2048 kbit/s connector board.
J3
EXTERNAL
REFERENCE
2
T1
1
6
5
R1
XF65502#
J4
SEND
DATA
2
R2
T2
1
6
5
XF65502#
S1
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
MC-A
MC-B
SD-A
SD-B
RD-A
RD-B
SW DIP-8
J5
RECEIVE
DATA
2
R3
T3
1
6
5
XF65502#
J2
1
9
2
10
3
11
4
12
5
13
6
14
7
15
8
SD-A
SD-B
SD-A
SD-B
RD-A
RD-B
RD-A
RD-B
MOD FLT
MC-A
DMD FLT
MC-B
MOD FLT
MC-A
DMD FLT
MC-B
CONNECTOR DB15S
1
9
2
10
3
11
4
12
5
13
6
14
7
15
8
J1
CONNECTOR DB15P
Figure 3-11. G.703 2048 kbit/s Connector Board Schematic Diagram
Rev. 5
3–29
Configuration
SDM-650B Satellite Modem
The G.703 2048 kbit/s optional connector board provides the balanced signals on a
15-pin female D connector. These signals are the same as the G.703 interface connector.
Refer to Section 3.2.4.4 for the connector pinouts.
The unbalanced signals are accessible from J3, J4, and J5. A description of available
unbalanced signals and directions is described in the following paragraphs.
3.2.4.6 External Reference (J3)
The external reference input signal has two inputs. The BNC connector, J3, has the
unbalanced input signal, and the DB15 connector has the balanced input signal.
To use the unbalanced input on the BNC connector, SW1 positions 1 and 2 must be
closed (close to PCB).
To use the balanced input on the DB15 connector, SW1 positions 1 and 2 must be open
(away from PCB).
The switch pack is located on the optional G.703 2048 kbit/s connector board.
3.2.4.7 Send Data (J4)
The send data output signal has two outputs. The BNC connector, J4, has the unbalanced
output signal, and the DB15 connector has the balanced output signal.
To use the unbalanced output on the BNC connector, SW1 positions 3 and 4 must be
closed (close to PCB).
To use the balanced output on the DB15 connector, SW1 positions 3 and 4 must be open
(away from PCB).
The switch pack is located on the optional G.703 2048 kbit/s connector board.
3.2.4.8 Receive Data (J5)
The receive data input signal has two inputs. The BNC connector, J5, has the unbalanced
input signal, and the DB15 connector has the balanced input signal.
To use the unbalanced input on the BNC connector, SW1 positions 5 and 6 must be
closed (close to PCB).
To use the balanced input on the DB15 connector, SW1 positions 5 and 6 must be open
(away from PCB).
The switch pack is located on the optional G.703 2048 kbit/s connector board.
3–30
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2.4.9 Specification
Pairs
Circuits Supported
Data Rate
Pulse Width (RD)
Line Code
RD Amplitude
SD Amplitude
Jitter Attenuation (SD)
Modulator Fault
Demodulator Fault
Symmetrical pair, coaxial pair optional.
SD, RD, MOD FAULT, DEMOD FAULT.
2.048 Mbit/s, ± 50 PPM.
244, ± 25 ns.
AMI or HDB3 (selectable).
3.00, ± 0.3V pk into a 120Ω termination.
3, ± 1.5V pk into a 100Ω termination.
Exceeds CCITT G.823, specification for 2048 kbit/s.
Open collector output.
15V max.
20 mA current sink.
Fault is open circuit.
Open collector output.
15V max.
20 mA current sink.
Fault is open circuit.
3.2.5 Asynchronous Overhead Interface
3.2.5.1 Functional Description
The asynchronous overhead interface module consists of three subassemblies:
•
•
•
Connector board is AS/1328.
Data processor board is AS/1289.
Terrestrial interface is AS/1311.
Dash #
1311-1
1311-2
1311-3
Interface
RS-422
V.35
G.703
With AUPC
1311-4
1311-5
1311-6
The connector board provides the physical interface using a 50-pin D connector.
The terrestrial interface contains all circuitry required for G.703, RS-422, MIL-STD-188,
and V.35 type interfaces for synchronous data, and RS-232-C and RS-485 type interfaces
for asynchronous data.
The data processor contains all circuitry required for multiplexing the synchronous and
asynchronous data streams, as well as data rate synthesizers and the optional
plesiochronous buffer.
Refer to Figure 3-12 for a block diagram of the asynchronous overhead interface.
Rev. 5
3–31
Configuration
SDM-650B Satellite Modem
RECEIVE SECTION
TRANSMIT SECTION
ES TO ES ASYNC
FRAMING/
TIMING
LOGIC (MUX)
RS-232
INTERFACE
P/O
INT
LPBK
P/O
INT
LPBK
MODEM
DEFRAME/TIMING
LOGIC (DEMUX)
RS-232
INTERFACE
ES TO ES
ASYNC
TX DEJITTER
G.703
CLK
DATA
CLK
PLESIOCHRONOUS
BUFFER
P/O
BASE
BAND
LPBK
T1/E1 INTERFACE
T2/E2
T1/E1
T2/E2
G.703
INTERFACE
P/O
BASE
BAND
LPBK
RS-422
INTERFACE
MIL-STD
188-114
RS-422 INTERFACE
MIL-STD-188-114
V.35
INTERFACE
CLK
DATA
CLK
DATA
V.35 INTERFACE
DATA
SATELLITE CLOCK
EXTERNAL REFERENCE CLOCK
(TRANSMIT TERR CLOCK)
INTERNAL CLOCK
CLOCK
SYNTHESIS
INTERNAL CLOCK
TRANSMIT TERR CLOCK
EXTERNAL REFERENCE CLOCK
CLOCK SYNTHESIS
Figure 3-12. Asynchronous Overhead Interface Block Diagram
3.2.5.2 Terrestrial Interface
The terrestrial interface, AS/1311, forms the top (when mated with the connector board)
of the 2-board module. The interface contains all balanced pair drivers and receivers for
RS-422, MIL-STD-188, and V.35.
Data inputs are SD and transmit clock (TT or SCTE).
Data outputs are:
•
•
•
3–32
Modem reference clock (SCT or ST)
Receive data (RD)
Receive clock (RT or SCR)
Rev. 5
SDM-650B Satellite Modem
Configuration
The “handshake” asynchronous signals are:
•
•
•
•
•
•
RTS
CTS
DM
DSR
RR
RLSD
This board may otherwise contain the circuitry for transformer balanced data interfaces
supporting CCITT G.703 parameters. Data inputs are SD, and outputs are RD. Data rates
of 1.544, 2.048, 6.312, and 8.448 Mbit/s are supported.
Note: 6 and 8 Mbit/s are not supported by the modem.
Line codes for zero substitution are B6ZS, B8ZS, and HDB3. AMI is also supported. The
configuration of this section is determined during production and is not user selectable in
the field.
The asynchronous data channel has three interface options. The RS-232-C electrical
interface allows full-duplex operation. The RS-485 4-wire option also allows full-duplex,
and RS-485 2-wire allows half-duplex operation. These options are jumper selectable.
Tables 3-6 and 3-7 describe the configuration of the jumpers for the various options and
data rates. Figure 3-13 shows the jumper locations.
JP11
1
JP11
1
2
AS/1311 REV___
ASYNC OVERHEAD TERRESTRIAL INTERFACE BOARD
JP1
1
1
JP4
JP5
JP6
JP7
1
1
1
JP8
1
JP13
1
1
1
JP12
JP9
JP2
2
1
2
JP3
1
JP10
1
Figure 3-13. Asynchronous Overhead Jumpers
Rev. 5
3–33
Configuration
SDM-650B Satellite Modem
Table 3-6. Asynchronous Overhead Jumper Table
JP #
JP1
JP2
JP3
JP10
JP11
JP12
JP8, JP9, JP13
Pin #
Function
1 to 3, and 2 to 4
V.35, RS-422, MIL-STD-188
3 to 5, and 4 to 6
G.703
Auto TX CLK Phase Select
1 to 2
Fixed Phase, Normal
3 to 4
Fixed Phase, Inverted
5 to 6
1 to 2
G.703 data activity detect
2 to 3
TX Terr CLK activity detect
1 to 2
V.35 operation
2 to 3
RS-422, MIL-STD-188 operation
1 to 2
Normal SCT output
3 to 4
TX CLK chained to SCT output
1 to 2
2-wire operation
2 to 3
4-wire operation
Asynchronous
1 to 2
RS-485
2 to 3
RS-232-C
Table 3-7. Data Rate Jumper Table
Data Rate
1.544 Mbit/s
2.048 Mbit/s
2.048 Mbit/s
6.312 Mbit/s
6.312 Mbit/s
8.448 Mbit/s
3–34
Impedance
BAL−100
BAL−120
UNBAL−75
BAL−110
UNBAL−75
UNBAL−75
JP4
OFF
OFF
OFF
1 to 2
OFF
OFF
JP5
ON
ON
ON
OFF
OFF
ON
JP6
ON
ON
ON
OFF
OFF
ON
JP7
OFF
OFF
OFF
OFF
OFF
OFF
Voltage
5.8 Vp-p
5.8 Vp-p
4.6 Vp-p
1.8 Vp-p
3.3 Vp-p
4.8 Vp-p
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2.5.3 Multiplexer
The data processor, AS/1289, forms the bottom of the 2-board module. This board
contains the data multiplexer and demultiplexer.
The synchronous data stream is multiplexed with a 1/15 overhead channel, and the
resultant information is interfaced to the modulator/coder section of the modem.
The input clock is normally the recovered clock from the terrestrial interface board
(SCTE), but the modem reference clock can be used by selecting INT Clock.
The 1/15 overhead channel is composed of:
•
•
•
•
Framing signals
Flags
Spare bit positions
Asynchronous data stream
The maximum asynchronous data rate is limited to 1.875% of the synchronous data rate.
3.2.5.4 Demultiplexer
Receive data and clock from the demodulator/decoder is input to the demultiplexer. The
demultiplexer synchronizes to the frame pattern and separates the synchronous and
asynchronous data. Synchronization is indicated by the DEMUX lock LED on the front
edge of the board.
The synchronous data is dejittered and interfaced either to the optional plesiochronous
buffer or to the terrestrial interface board.
Rev. 5
3–35
Configuration
SDM-650B Satellite Modem
3.2.5.5 Plesiochronous Buffer
User data from the DEMUX section is fed into a plesiochronous buffer. The buffer size is
user selectable in 16-bit increments, from 384 to 262144 bits. The buffer is automatically
centered on resumption of service after an outage, or may be commanded to center in the
interface configuration section (from the front panel or remotely). For obvious reasons,
manual centering will generally not be plesiochronous.
The fill status is available as a monitor function and is accurate to 1%. Overflow or
underflow incidents will be momentarily indicated by red LEDs on the module. They are
stored in the Stored Faults (StFaults) section of the M&C status registers, along with the
date and time of the incident, provided by the modem internal clock. They are stored in
battery-backed RAM.
The user may select to have the data clocked out of the buffer from four clock sources:
•
•
•
•
Recovered EXT clock from user terrestrial input data
User-supplied EXT-REF reference clock
Satellite clock which is phase-locked to the demultiplexer
Internal clock source
Satellite clock selection is similar to buffer bypass. Problems on either the TX terrestrial
clock or the external clock (if selected) will substitute satellite clock, and a fault will be
signaled.
3.2.5.6 Remote Interface Specification
Refer to Appendix B, Section B.2, for the remote interface specifications for the
asynchronous overhead channel unit.
3–36
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2.5.7 Interface Connector Pinouts
The asynchronous interface is provided on a 50-pin female D connector accessible from
the rear panel of the modem. Screw locks are provided for mechanical security of the
mating connector.
Signal Function
GROUND
T1E1 SEND DATA A
T1E1 SEND DATA B
EXTERNAL CLOCK A
EXTERNAL CLOCK B
T1E1 RECEIVE DATA A
T1E1 RECEIVE DATA B
TX DATA B (ASYNC)
SEND DATA A
SCT SIGNAL A
TX DATA A (ASYNC)
SEND DATA B
SCT SIGNAL B
RX DATA B (ASYNC)
RECEIVE DATA A
RECEIVE CLOCK A
RX DATA A (ASYNC)
RECEIVE DATA B
RECEIVE CLOCK B
TRANSMIT TIMING A
REQUEST TO SEND A
REQUEST TO SEND B
TRANSMIT TIMING B
RECEIVER READY A
RECEIVER READY B
RS-422 TX DATA A
CLEAR TO SEND B
DATA SET READY A
DATA SET READY B
CTS A
Rev. 5
Name
GND
T1E1-SDA
T1E1-SDB
EXCA
EXCB
T1E1-RDA
T1E1-RDB
TXD-B
SDA
SCT/STA
TXD-A
SDB
SCT/STB
RXD-B
RDA
SCR/RTA
RXD-A
RD-B
SCR/RTB
SCTE/TTA
RTSA
RTSB
SCTE/TTB
RLSD/RRA
RRB
R422TXDA
CTSB
DSR/DMA
DMB
CTSA
Pin #
1, 2
34
18
35
19
36
20
4
37
21
5
38
22
6
39
23
7
40
24
12
45
29
13
46
30
14
31
48
32
47
3–37
Configuration
SDM-650B Satellite Modem
3.2.5.8 Asynchronous Interface Specifications
Main Channel
MIL-STD-188-114.
RS-422/-449.
V.35.
G.703.
Data Rates
9.6K, 19.2K, 32 kbit/s to 8.448 Mbit/s.
G.703 Data Rates
1.544 Mbit/s.
(Jumper Selectable)
2.048 Mbit/s.
6.312 Mbit/s.
8.448 Mbit/s.
G.703 Line Code
AMI, B8ZS, B6ZS, HDB3.
Transmit Clock Reference
Internal modem reference or external transmit clock
(SCT or TT).
Jitter Attenuation
Per G.703.
Pulse Mask
Per G.703.
Overhead Channel
Overhead Rate
16/15 of main channel.
ASYNC Channel Rate (max.) < 1.875% of main channel.
ASYNC Channel Interface
RS-232-C.
2-wire RS-485 half-duplex.
4-wire RS-485 full-duplex.
Connector
25-pin D on breakout panel.
Baud Rates, Asynchronous
110, 150, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400
bit/s.
Asynchronous Format
5, 6, 7, or 8 data bits.
Even, Odd, or No Parity.
1 or 2 stop bits (1 or 1.5 for 5 bit).
Buffer Specifications (Pleisiochronous/Buffer Operation)
Buffer Size
384 to 262144 bits, in 16-bit steps.
Buffer Fill Status
Monitored accurate to ± 1%.
Buffer Centering
Automatic or Manual.
Buffer Clock Reference
Transmit.
Internal (10-5 Stability).
External.
Receive (Buffer Bypass).
External Clock Amplitude
Differential 0.5 to 5 Vp-p.
Unbalanced Mode 0 to 5 VDC.
External Clock Frequency
256 to 2048 kHz, in 64 kHz steps.
External Clock Impedance
100Ω.
External Clock Input Type
Sine or Square wave.
50%, ± 10%.
Physical Interface
(Factory Option)
3–38
Rev. 5
SDM-650B Satellite Modem
Configuration
3.2.6 Asynchronous Breakout Panel
The asynchronous breakout panel supports the use of the asynchronous interface in the
modem.
For more information, refer to the ASYNC Breakout Panel Installation and Operation
Manual.
Rev. 5
3–39
Configuration
SDM-650B Satellite Modem
3.3 Doppler Buffer
The Doppler buffer assembly is an option that plugs on to the modem interfaces, that
provides elastic buffering to the receive data channel. The Doppler buffer compensates
for the effect of satellite movement or disparity between transmit and receive clocks, and
can be used at data rates of 9.6 kbit/s to 2.5 Mbit/s.
Note: 120Ω impedance-matching resistors are required on the AS/0627, AS/0569, and
AS/0679 PCBs.
The Doppler buffer attaches into the receive data path on the interface assembly at TTL
signal levels. The buffer should be attached before the signals are configured to the
specific interface type.
The buffer assembly is compatible with many different interface types.
The clock source for the buffer output can be selected from one of three sources:
•
•
•
Receive channel (effective bypass mode)
Modem transmit clock
External customer supplied reference clock
If the transmit clock source is selected, the buffer output is used after being recovered and
dejittered (if necessary). Any signal with which the transmit side is designed to work can
supply a valid buffer output clock.
Jumpers on the buffer determine local clock source control, or the M&C system control.
The modem software must be configured for buffer support in order to use M&C
functions from the front panel.
To select the required buffer depth for the system, the maximum peak-to-peak
transmission delay variation has to be known.
Refer to Table 3-8 for jumper settings.
Refer to Table 3-9 for the delay variation of an INTELSAT satellite.
3–40
Rev. 5
SDM-650B Satellite Modem
Configuration
Table 3-8. Jumper Selections
Function
Clock Source Control By M&C
Clock Source Receive (Bypass)
Clock Source Transmit CLK
Clock Source External
Center Control By M&C
Center Control Local
Clear Flags Control By M&C
Clear Flags Local
Buffer Depth Control By M&C
Buffer Depth 512 Bits
Buffer Depth 1024 Bits
Buffer Depth 2048 Bits
Buffer Depth 4096 Bits
Buffer Depth 8192 Bits
Buffer Depth 16384 Bits
Buffer Depth 32768 Bits
Buffer Depth 65536 Bits
Install
JP8, JP9
JP11
JP10, JP11
JP10
JP1
Remove
JP10, JP11
JP8, JP8, JP10
JP8, JP9
JP8, JP9, JP11
JP1
JP2
JP3, JP4, JP5, JP14
SW1-Closed
SW2-Closed
SW3-Closed
SW4-Closed
SW1-Open
SW2-Closed
SW3-Closed
SW4-Closed
SW1-Closed
SW2-Open
SW3-Closed
SW4-Closed
SW1-Open
SW2-Open
SW3-Closed
SW4-Closed
SW1-Closed
SW2-Closed
SW3-Open
SW4-Closed
SW1-Open
SW2-Closed
SW3-Open
SW4-Closed
SW1-Closed
SW2-Open
SW3-Open
SW4-Closed
SW1-Open
SW2-Open
SW3-Open
SW4-Closed
JP2
SW3-1, 2, 3, and 4 — Open
JP3, JP4, JP5, JP14
JP3, JP4, JP5, JP14
JP3, JP4, JP5, JP14
JP3, JP4, JP5, JP14
JP3, JP4, JP5, JP14
JP3, JP4, JP5, JP14
JP3, JP4, JP5, JP14
JP3, JP4, JP5, JP14
Table 3-9. INTELSAT Delay Variations
Parameter
Maximum Variations
Maximum Rate of Variations
Rev. 5
0.5
1.1
40
1.0
1.8
67
Inclination (Degrees)
1.5
2.0
2.5
3.0
2.6
3.3
4.1
4.8
94
121 148 175
Units
ms
ns/sec
3–41
Configuration
SDM-650B Satellite Modem
The formula for calculating the buffer depth is:
Buffer Depth (bits) = Bit Rate (bit/s) x Max. Delay Variation
Contact the satellite company to determine the delay variation of a particular domestic
satellite.
The buffer depth capacity can be set either through the M&C or manually with a DIP
switch on the buffer. Jumpers and optional modem software determine if the control is
local or through the M&C.
When an overflow or underflow occurs, the buffer will automatically reset itself to the
center, and set the respective indicator.
The buffer is not plesiochronous.
Data framing is not required for proper operation.
The buffer is centered at power-up, and may be re-centered manually or through the
M&C, depending on jumper settings on the assembly.
Refer to Figure 3-14 for the Doppler buffer daughter card and jumper selections.
Refer to Table 3-8 to determine settings.
CAUTION
A problem can result in the switch system when using the buffer with the
source clock set to TX CLK. When the TX section switches over to the
back-up modem, the source clock is no longer present at the prime mode.
The internal oscillator in the prime modem will free-run at the frequency
± 50 PPM from the center. The prime modem running free will eventually
cause the Doppler buffer in the prime modem to overflow or underflow. Two
lines are provided on the connector called the Master Clock (MC-A and MCB) that prevent the modem from overflowing or underflowing.
The pinouts on the 15-pin connector are:
•
•
3–42
Pin 7 for MC-A
Pin 8 for MC-B
Rev. 5
SDM-650B Satellite Modem
Configuration
Figure 3-14. AS/3812 Doppler Buffer Daughter Card
Pinouts on the 34-pin V.35 are:
•
•
“c” for MC-A
“d” for MC-B
The pinouts on the 37-pin connector are:
•
•
Pin 16 for MC-A
Pin 34 for MC-B
The electrical configuration of these lines is the RS-422.
The jumper selection must be set to external clock in order to use the external reference.
The asynchronous channel unit has a plesiochronous buffer and is selectable in 16-bit
increments, from 384 to 262144 bits.
Notes:
1. Maximum variations = peak-to-peak uplink plus downlink.
2. Maximum rate of variations = uplink plus downlink.
Rev. 5
3–43
Configuration
SDM-650B Satellite Modem
3.3.1 Buffer Setup
The receive buffer allows for:
•
Plesiochronous buffering of two dissimilar clock frequencies: the far end transmit
clock and the local network clock frequency. The clocks may be very close in
frequency to each other and will normally slip at a constant rate. Figure 3-15
shows plesiochronous operation of dissimilar clocks. If incoming traffic is too
fast, an occasional bit will be lost. If incoming traffic is too slow, an occasional
bit will be repeated.
•
Doppler buffering of the signal from the satellite. A Doppler shift results from
the satellite’s figure 8 shaped orbit over a period of one day. A Doppler shift
should not result in a clock slip; the buffer constantly fills and empties.
If two earth stations are configured as a master/slave unit, then the buffer need only be
configured for Doppler operation. The buffer has sufficient capacity for the Doppler shift
on the outward and return paths.
A buffer setup for the Doppler operation will typically require less depth than one
intended for both Doppler and plesiochronous operations.
3–44
Rev. 5
SDM-650B Satellite Modem
Configuration
F1 is not EXACTLY equal to f2.
Plesiochronous Operation
Too Fast
Too Slow
Bit 1
Bit 1
Bit 1
Bit 1
Bit 2
Bit 2
Bit 2
Bit 2
Error
Bit 3
Error
Bit 3
Bit 3
Bit 3
Bit 4
Bit 5
Bit 5
Bit 6
Bit 3
Bit 4
Bit 6
Bit 4
Bit 5
Bit 7
Bit 7
Bit 5
Interface
Interface
Figure 3-15. Clock Slip Diagram
Rev. 5
3–45
Configuration
SDM-650B Satellite Modem
3.3.1.1 Buffer Size
The depth of the receive buffer will depend upon four parameters:
•
•
•
•
Doppler shift caused by satellite
Stability of each clock (plesiochronous/Doppler operation only)
Frame/multiframe length of multiplexed data format
Allowable time between clock slips
3.3.1.2 Doppler
A geostationary satellite with a 24-hour orbit should be positioned directly over the
equator. The exact inclination of the satellite (relative to the equator) is influenced by the
gravity of the earth, moon, and sun. Solar wind and station keeping motors are required
to maintain the satellite’s orbital position.
When viewed from the earth, the satellite’s orbit appears to be an ellipse around the
planet. However, the orbit changes to a figure 8 shape as the angle of inclination
increases.
The satellite’s orbit can result in a peak-to-peak altitude variation of 0.2% (85 km). A
newly launched satellite’s orbit will be typically ± 0.1° (150 km). The total effect will be
172 km relative to the nominal 42,164 km radius.
The variation in propagation delay will typically be 1.15 ms (up to the satellite and back
down), depending upon the location of the earth station to the satellite. The 2 ms delay is
used for most commercial satellites.
Since station keeping involves using fuel in the motors, the lifetime of the satellite can be
extended. The satellite’s age can be prolonged by allowing the satellite to drift into a
wider figure 8 orbit and using the motors less.
The older satellites will be found to be in a more inclined orbit with the station keeping
varying in latitude by as much as ± 4.0°. The total effect of the inclined orbit may result
in a typical variation in path delay of 35 ms.
3–46
Rev. 5
SDM-650B Satellite Modem
Configuration
3.3.1.3 Plesiochronous
The stability of station reference clocks is normally 10-11 that is derived from a cesium
standard. When the stability is exceptionally high, the two clocks are not in sync with
each other. Eventually, the two reference clocks will pass by each other.
The clock used for the transmit signal passes over the satellite, but will not be used at the
receive earth station where a national network derives its timing locally. A buffer will fill
up with data using the clock from the satellite, and will empty using the local clock. The
buffer ensures that the buffer overflows or underflows at regular determinable intervals.
The intervals typically occur every 40 days.
The buffer depth required, from center to end, will be calculated as follows:
Buffer Depth = Minimum Slip Period (sec) x Stability of Far End (Transmit) Clock +
Stability of Local Clock
The following is an example on how to calculate a buffer depth:
Far end (transmit) clock stability
Local (buffer) clock stability
Minimum clock slip
1 E-9
1E-11
40 days
Buffer Depth = (40 x 24 x 60 x 60) x (1E-9 + 1E-11) = 3.49 ms
The buffer will either be filled or empty, depending upon the frequency relationship of
the two clocks. The total buffer depth will be 2 x 3.49 ms = 6.98 ms.
3.3.1.4 Frame/Multiframe Length
The depth of the receive buffer required has been discussed above and is applicable to all
unframed data.
Framed data (i.e., 2048 kbit/s G732 or 1544 kbit/s G733) is desirable to provide slips in
pre-defined locations. There are two advantages of organized slip locations:
•
•
In relation to the frame, multiplexing equipment does not lose sync.
Outages on any channel are kept to a minimum.
A 2048 kbit/s frame structure commonly used is G732. The frame structure has a length
of 256 bits, with 16 frames per multiframe (4096 bits total or 2 ms).
Rev. 5
3–47
Configuration
SDM-650B Satellite Modem
3.3.1.5 Total Buffer Length
The size of the buffer will be determined by the Doppler, plesiochronous, and the frame
and multiframe length (the last three sections). Using the three examples given in the last
three sections, the total buffer depth (end to end) will be:
Doppler + Plesiochronous ms (rounded up to the nearest multiframe)
(e.g., 1.15 + 6.98 = 8.13 ms)
If the multiframe length is 2 ms, then the nearest multiframe will be 10 ms, or 20480 bits.
3.3.1.6 Converting
To convert bits to seconds:
1/Data Rate times Bits = Seconds
To convert seconds to bits:
Data Rate times Seconds = Bits
3–48
Rev. 5
SDM-650B Satellite Modem
Configuration
3.4 Doppler Buffer Specification
Buffer Size (bits)
Clock Source
Data Rate
Indicators
Controls
Miscellaneous
512, 1024, 2048, 4096, 8192, 16384, 32768, 65536
Receive, transmit, and external clock
9.6 kbit/s to 2.4 Mbit/s
Buffer overflow (latched)
Buffer underflow (latched)
Reset buffer to center
Reset underflow and overflow indicators
Buffer depth
Output clock source
Control functions jumper
Selectable local or M&C system (optional)
Buffer automatically recenters on underflow and overflow
3.5 I/O Connectors
J1 25-pin, 0.1” spaced, dual-row header.
Pin #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Rev. 5
Description
/BUFBDS
GND
TCLK
NC (/TCLK)
DB0
DB1
DB2
DB3
DB4
DB5
DB6
DB7
RCLK-SND
RDATA-SND
RCLK-RTN
RDATA-RTN
/BUFALE
BUFWR
BUFRD
EXTCLK
VCC
VCC
SPARE
GND
3–49
Configuration
SDM-650B Satellite Modem
3.6 Interface Clocking Options
Clocking of the data from the terrestrial circuits to the satellite, and vice versa, will
depend upon the application. The most common options and recommended
configurations are described in the following sections.
3.6.1 Master/Slave
This application is used where the far end earth station does not have local access to a
high stability reference clock, or when it is not required to synchronize with a local clock.
The disadvantage of the master/slave application is that the signal received at the slave
station is subject to Doppler shift.
Note: The length of the buffer at the master end will need to be twice the length that is
normally required (since it will be compensating for the Doppler shift on the outward and
return paths).
3–50
Rev. 5
SDM-650B Satellite Modem
Configuration
3.6.1.1 Master/Slave RS-422 or V.35
Refer to Figure 3-16 for the RS-422 or V.35 master/slave configuration.
Figure 3-16. RS-422 or V.35 Master Slave Configuration
Notes:
1. The clock may be looped back by using JP10 on the interface board.
2. Refer to Tables 3-1 or 3-2 for more information.
RS-422 Clock Loopback
Join RT-A to TT-A
Join pin 8 to pin 17
Join RT-B to TT-B
Join pin 26 to pin 35
V.35 Clock Loopback
Join SCR-A to SCTE-A
Join pin V to pin U
Join SCR-B to SCTE-B
Join pin X to pin Y
Note: By wiring the interface for clock turnaround, the impedance will be
reduced. This generally will cause no problem, providing the cable length to the
final terminal equipment is not excessive. Selecting “no loading” at the terminal
equipment will ensure correct line matching.
Rev. 5
3–51
Configuration
SDM-650B Satellite Modem
3.6.1.1.1 Modem Settings (Master)
1. TX-CLOCK: EXT.
2. Install JP10 and JP11 on buffer card (AS/3812).
3. Set S3 as required. Refer to Table 3-9.
3.6.1.1.2 Modem Settings (Slave)
1. TX-CLOCK: EXT.
2. Set S3 to minimum size, and install JP11 on buffer card (AS/3812). Refer to
Table 3-9.
3–52
Rev. 5
SDM-650B Satellite Modem
Configuration
3.6.1.2 Master/Slave G.703
Refer to Figure 3-17 for the G.703 master/slave configuration.
Note: There is no loop timing selection on board for G.703. It is assumed that any G.703
termination equipment will extract the clock from the satellite signal, and turn it around
for re-transmitting. The settings for the master and slave modems are the same as listed in
previous sections.
Figure 3-17. G.703 Master Slave Configuration
Rev. 5
3–53
Configuration
SDM-650B Satellite Modem
3.6.1.3 Master/Slave X.21
Refer to Figure 3-18 for the X.21 master/slave configuration.
Figure 3-18. X.21 Master/Slave Configuration
Note: On Rev. E boards, there are on-board jumpers to loop back the clock. Refer to
Table 3-1 (see the note in the previous example).
3.6.1.3.1 Modem Settings (Master)
•
•
•
TX-CLOCK: INT.
Install JP10 and JP11 on buffer card (AS/3812).
Set S3 as required. Refer to Table 3-9.
3.6.1.3.2 Modem Settings (Slave)
•
•
•
3–54
TX-CLOCK: EXT.
Install JP11 on buffer card (AS/3812).
Set S3 as required. Refer to Table 3-9.
Rev. 5
SDM-650B Satellite Modem
Configuration
3.6.1.4 Master/Slave External Station Clock
Figure 3-19 shows the master/slave external station clock configuration diagram.
Note: Clock must be looped externally at slave end. (For RS-422 and V.35, see the note
in the previous example.)
Figure 3-19. G.703 Master Slave Configuration
3.6.1.4.1 Modem Settings (Master)
•
•
•
TX-CLOCK: EXT.
Install JP10 on buffer card (AS/3812), and set S3 as required.
Refer to Table 3-9.
3.6.1.4.2 Modem Settings (Slave)
•
•
Rev. 5
TX-CLOCK: EXT.
Set S3, and install JP11 on buffer card (AS/3812).
3–55
Configuration
SDM-650B Satellite Modem
3.6.2 Master/Master
This application is used where both earth stations have high stability clocks available,
and the received data is to be clocked onto the local network.
The disadvantage of the master/master application is that the receive data will slip, as the
clocks will not be synchronized. By using very high stability clocks, the expected time
between slips can be many days.
The buffer clock will normally automatically revert to the low stability internal reference.
3.6.2.1 Master/Master (Customer Clock)
Refer to Figure 3-20 for the master/master customer clock configuration.
Figure 3-20. Master/Master Customer Clock Configuration
3–56
Rev. 5
SDM-650B Satellite Modem
Configuration
3.6.2.1.1 Modem Settings (Master)
•
•
•
Rev. 5
TX-CLOCK: EXT.
Install JP10 and JP11 on buffer card (AS/3812).
Set S3 as required. Refer to Table 3-9.
3–57
Configuration
SDM-650B Satellite Modem
3.6.2.2 Master/Master (Station Clock)
Care should be taken when using this mode. Make sure that the station clock is also used
to synchronize the transmit data. Phasing problems may also occur between the transmit
data and the station clock input. For this reason, it is better to use the TERR clock on
transmit.
Refer to Figure 3-21 for a diagram of the master/master station clock configuration.
Figure 3-21. Master/Master Station Clock Configuration Diagram
3–58
Rev. 5
SDM-650B Satellite Modem
Configuration
3.6.2.2.1 Modem Settings (Master)
•
TX-CLOCK: EXT.
•
Install JP1 and JP10 on buffer card (AS/3812).
•
Set S3 as required:
•
Rev. 5
Š
If using the G.703 2048 kbit/s interface (AS/0679), set SW1-6 and SW1-7 to
open, and the remainder to closed.
Š
If using the T1/DS1 1544 kbit/s interface (AS/0569), set SW1-1 to closed for
AMI line coding, and open for B8ZS line coding.
SW1-2 through SW1-4 should be set as required.
3–59
Configuration
SDM-650B Satellite Modem
This page is intentionally left blank.
3–60
Rev. 5
Chapter 4.
OPERATION
This chapter provides front panel operation information for the standard SDM-650B
modem. The following firmware version is described:
•
•
Firmware number:
Software version:
FW/0713-35R
4.16
Notes:
1. For front panel operation information for the modem with the asynchronous
overhead channel unit installed, refer to Appendix F.
2. For front panel and remote control operation information for the modem with the
Trojan interface installed, refer to Appendix G.
3. For remote control operation information for the modem, refer to Appendix B.
Rev. 5
4–1
Operation
SDM-650B Satellite Modem
4.1 Front Panel
The modem front panel (Figure 4-1) provides the local user interface, which is necessary
to configure and monitor the modem status.
Figure 4-1. SDM-650B Front Panel View
The front panel features a 16-character, 2-line LCD display, and 6-key keypad that
provides sophisticated functions, yet is easy to use. Eight LED indicators are also present
on the front panel to provide overall status at a glance.
All functions are accessible at the front panel by entering one of five pre-defined Select
categories or levels:
•
•
•
•
•
4–2
Configuration (Config)
Monitor
Faults
Stored Faults (StFaults)
Utility
Rev. 5
SDM-650B Satellite Modem
Operation
4.1.1 LED Indicators
General modem status and summary fault information are indicated by eight LEDs on the
front panel. The indicators are defined as follows:
Faults
Transmit
Receive
Common
Stored
Color
Red LED
Red LED
Red LED
Red LED
Power On
Transmitter On
Green LED
Green LED
Carrier Detect
Test Mode
Green LED
Yellow LED
Description
Indicates that a modulator fault condition exists.
Indicates that a demodulator/decoder fault condition exists.
Indicates that a common equipment fault condition exists.
Indicates that a fault has been logged and stored. The fault
may or may not be active.
Indicates that power is applied to the modem.
Indicates that the transmitter is currently ON. This indicator
reflects the actual condition of the transmitter as opposed to
the programmed condition.
Indicates that the decoder is locked.
Flashes when the modem is in a test configuration.
4.1.2 Controls
The modem is locally operated by using the following six keys:
Key
[ENTER]
[CLEAR]
[←] and [→]
[↑] and [↓]
Rev. 5
Function
[ENTER] is used to select a display function, or to execute a change to the
modem’s configuration.
[CLEAR] is used to back out of a selection, or to cancel a configuration change
which has not been executed. Pressing [CLEAR] generally returns the display to
the previous selection.
These keys are used to move to the next selection or to move the cursor for
certain functions.
These keys are used primarily to change configuration data (numbers). The
keys are also used at times to move from one section to another.
4–3
Operation
SDM-650B Satellite Modem
The modem responds by beeping whenever a key is pressed.
•
A single beep indicates that the key pressed was a valid entry, and the
appropriate action was taken.
•
A double beep when a key is pressed indicates an invalid entry.
The modem front panel control uses a tree structured menu system (Tables 4-1 through
4-6) to access and execute all functions. The base level of this structure is the sign-on
message, which is displayed at the front panel upon modem power-up.
•
•
Line 1 of the sign-on message is the modem model number.
Line 2 is the version number of the firmware implemented in the modem.
The main level of the menu system is the Select menu, which may be accessed from the
base level by pressing any of the arrow keys. From the Select menu, any one of five
functional categories can be chosen:
•
•
•
•
•
Configuration
Monitor
Faults
Stored faults (StFaults)
Utility
Use [←] and [→] to move from one selection to another. When the desired function is
displayed on line 2, enter that level by pressing [ENTER]. Once the desired the functional
level is entered, move to the desired function by using [←] and [→].
4.1.3 Menus and Options Overview
Refer to Section 4.1.4 for menu and option explanations.
Table 4-1. Main Front Panel Menu (Standard)
Screen
Submenus/Options
SDM-650
SW_4.16
SELECT
4–4
Comments
This is an information-only screen.
CONFIG
MONITOR
FAULTS
StFAULTS
UTILITY
Go to Table 4-2.
Go to Table 4-3.
Go to Table 4-4.
Go to Table 4-5.
Go to Table 4-6.
Rev. 5
SDM-650B Satellite Modem
Operation
Table 4-2. Select Configuration Menu
Menus
Submenus/Options
TX-x Code Rate
x = A, B, C, D, or V
RX-x Code Rate
TX_Freq
x = A, B, C, D, or V
50.0000 to 90.0000 MHz
or 100.000 to 180.000 MHz
50.000 to 90.0000 MHz
or 100.000 to 180.000 MHz
ON
OFF
-5.0 dBm to -30 dBm
RX_Freq
RF_Out
TX_Power
RFLoopBk
SWP_RACQ
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
Internal
External
Normal
Inverted
0 to 999 Seconds
SWP_CNTR
-25000 to +25000 Hz
SWP_RNGE
0 to 50000 Hz
SWP_DIR
FORWARD +
REVERSE -
CW_Mode
BUF_CNTR
Center
Dual
Offset
Transmit
Receive
External
YES/NO?
BUF_SIZE
0 to 999
IFLoopBk
BBLoopBk
Scramblr
Dscrmblr
DifEncdr
TX_Clock
RX_Clock
BUF_clk
Rev. 5
Comments
In 2.5 kHz steps.
In 2.5 kHz steps.
In 0.5 dBm steps.
Displays information when fast
acquisition has been turned ON in the
Utility menu.
Displays information when fast
acquisition has been turned ON in the
Utility menu.
Displays information when fast
acquisition has been turned ON in the
Utility menu.
4–5
Operation
SDM-650B Satellite Modem
Table 4-3. Select Monitor Menu
Raw_BER
Menus
Submenus/Options
Range: < 1.0E-4 to 2549E-4
Corr_BER
Range: > 1E-8 to > 1E-3
Eb/N0
Range: < 3.2 dB to > 9.7 dB
SWP_FREQ
Range: -25000 to +25000 Hz
RXSignal
Range: < -60 dBm to > -30 dBm
Comments
Displays information when fast
acquisition has been turned ON in
the Utility menu.
Note: Data is not available or displayed when the decoder loses lock.
Table 4-4. Select Faults Menu
Menus
Mod_Flts
Dmd_Flts
CEq_Flts
Submenus/Options
RF_Syn
Data Clk
TClk Syn
I-Channl
Q-Channl
AGC levl
Module
C_Detect
RF_Syn
Data_Clk
I-Channl
Q-Channl
Dscramblr
BERthrsh
Module
Battery
-12 volt
+12 volt
+5 volt
Controlr
Intrface
Comments
Note: Fault conditions are displayed as a “+” on the screen.
4–6
Rev. 5
SDM-650B Satellite Modem
Operation
Table 4-5. Select Stored Faults (StFaults) Menu
Menus
Mod_Flt0 through Mod_Flt9
MM/DD/YY
HH/MM/SS
Dmd_Flt0 through Dmd_Flt9
MM/DD/YY
HH/MM/SS
CEq_Flt0 through CEq_Flt9
MM/DD/YY
HH/MM/SS
CLEAR ??
StFaults
Rev. 5
Submenus/Options
RF_Syn
Data_Clk
TClk_Syn
I-Channl
Q-Channl
AGC_levl
Module
C_Detect
RF_Syn
Data_Clk
I-Channl
Q-Channl
Dscrambl
BERthrsh
Module
Battery
-12 volt
+12 volt
+5 volt
Controlr
Intrface
YES/NO
Comments
4–7
Operation
SDM-650B Satellite Modem
Table 4-6. Select Utility Menu
Menus
Comments
Seconds (SS) reset at [ENTER].
Date
Submenus/Options
SS
HH:MM AM/PM
MM/DD/YY
LAMP TEST??
YES
Press [ENTER] to illuminate all front
panel LEDs for three seconds.
Add
xxxxyyyy
Address = 0 to 255
xxxx = Parity
Odd
Even
yyyy = 110 to 9600 Baud Rate
+20 dBm to -20 dBm
Time
POW ADJ
OP MODE
FAST ACQ
BERT_set
BUF_CNTL
FILTERS ADJUST
4–8
TX ONLY
RX ONLY
DUPLEX
ON
OFF
1E-3
1E-4
1E-5
1E-6
1E-7
1E-8
NONE
ON
OFF
MOD ADJ.
DMD ADJ.
Assign TX_Fltrs
Filters = A, B, C, D, or V
Assign RX_Fltrs
Filters = A, B, C, D, or V
In 0.5 dBm steps.
This is a factory setting, and should
not be changed by unauthorized
persons.
Rev. 5
SDM-650B Satellite Modem
Operation
4.1.4 Menu Explanations
Modem configuration may be viewed or changed by entering the Config level from the
Select menu on the front panel.
4.1.4.1 Select Configuration
Refer to Table 4-2.
Once the Config menu is entered, the configuration status of all parameters can be viewed
by using [←] and [→]. To change a configuration parameter, press [ENTER] to begin the
change process. Then, use the arrow keys to make the changes.
After the changes are made and the display represents the correct parameters, execute the
change by pressing [ENTER]. When [ENTER] is pressed, the necessary programming is
initiated by the modem. [CLEAR] allows the user nullify a change prior to execution.
The following table describes each configuration function in detail.
Configuration
TX-x Code Rate
RX-x Code Rate
Description
Transmitter rate selection. Select one of four pre-defined transmitter
coder/data rate combinations (A, B, C, or D), or a variable rate selection
(V).
On entry, the current transmitter rate is displayed with the flashing
cursor on the first character of the code rate on line 1, and the data rate
on line 2. Use the arrow keys to select one of four pre-defined rates.
Filters that are not present may display as N/A (not assigned) and
cannot be programmed. If the modem is equipped with the variable rate
option, TXV can also be selected and the desired data rate can be
entered. The BPSK TX code rate operation will be selectable from this
window. If one of the pre-defined filters are BPSK, the selection will
show up in the appropriate TX filter. If the modem has the variable rate
option, the variable rate filter may be entered and BP12 selected. Enter
the desired data rate.
Receiver rate selection. Select one of four pre-defined receiver
decoder/data rate combinations (A, B, C, or D), or a variable rate
selection (V).
On entry, the current receiver rate is displayed with the flashing cursor
on the first character of the code rate on line 1, and the data rate on line
2. Use the arrow keys to select one of four pre-defined rates. Filters that
are not present may display as N/A (not assigned), and cannot be
programmed. If the modem is equipped with the variable rate option,
TXV can also be selected and the desired data rated entered. The
BPSK RX code rate operation will be selectable from this window. If one
of the pre-defined filters are BPSK, the selection will show up in the
appropriate RX filter. If the modem has the variable rate option, the
variable rate filter may be entered and BP12 selected. Enter the desired
data rate.
Rev. 5
4–9
Operation
SDM-650B Satellite Modem
TX_Freq
Programs the modulator transmit frequency between 50 and 90 MHz, or
between 100 and 180 MHz, in 2.5 kHz steps.
On entry, the current transmitter frequency is displayed with the flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment or decrement the digit at the
flashing cursor. Press [ENTER] to execute the change.
RX_Freq
RF_Out
TX_Power
RFLoopBk
(Test Mode Configuration
Option)
IFLoopBk
(Test Mode Configuration
Option)
Note: The transmitter frequency is programmable within the specified
range (50 to 180 MHz), in 2.5 kHz steps. When the transmitter
frequency is changed, the transmitter is automatically turned OFF to
prevent the possible swamping of other channels. To turn the
transmitter ON, use the RF_Out function.
Programs the demodulator receive frequency between 50 and 90 MHz,
or between 100 and 180 MHz, in 2.5 kHz steps.
On entry, the current receive frequency is displayed with the flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment or decrement the digit at the
flashing cursor. Press [ENTER] to execute the change.
Programs the modulator output to ON or OFF.
On entry, the current status of the output is displayed with the flashing
cursor on the first character. Use the arrow keys to select ON or OFF.
Press [ENTER] to execute the change.
Programs the modulator output power level from -5 to -30 dBm, in
0.5 dB steps.
On entry, the current transmitter power level is displayed with the
flashing cursor on the first character. Use [↑] and [↓] to increase or
decrease the output power level, in 0.5 dBm steps. Press [ENTER] to
execute the change.
Programs the modem for RF loopback operation.
When RF loopback is turned ON, the demodulator is programmed to
the same frequency as the modulator. When RF loopback is turned
OFF, the demodulator is tuned to its previous frequency.
On entry, the current status of the RF loopback is displayed with the
flashing cursor on the first character. Use the arrow keys to select ON
or OFF. Press [ENTER] to execute the change.
Programs the modem for IF loopback operation.
When IF loopback is turned ON, the demodulator is connected to the
modulator output through an attenuator. The demodulator is
programmed to the same frequency as the modulator. An attenuator
within the modem connects the IF out to the IF in. When the IF
loopback is turned OFF, the demodulator is tuned to its previous
frequency, and is reconnected to the IF input.
On entry, the current status of the IF loopback is displayed with the
flashing cursor on the first character. Use the arrow keys to select ON
or OFF. Press [ENTER] to execute the change.
4–10
Rev. 5
SDM-650B Satellite Modem
Operation
BBLoopBk
Programs the modem for baseband loopback operation.
(Test Mode Configuration
Option)
When baseband loopback is turned ON, the data and timing signals are
hard-wired (relays) from the demodulator to the modulator. The DTE
baseband signals are also looped back from transmitter data and clock,
to receiver data and clock.
Scramblr
On entry, the current status of the baseband loopback is displayed with
the flashing cursor on the first character. Use the arrow keys to select
ON or OFF. Press [ENTER] to execute the change.
Programs the modulator for scrambler ON or OFF.
Dscrmblr
On entry, the current status of the scrambler is displayed with the
flashing cursor on the first character. Use the arrow keys to select ON
or OFF. Press [ENTER] to execute the change.
Programs the demod/decoder for descrambler ON or OFF.
DifEncdr
On entry, the current status of the descrambler is displayed with the
flashing cursor on the first character. Use the arrow keys to select ON
or OFF. Press [ENTER] to execute the change.
Programs the differential decoder ON or OFF.
TX_Clock
On entry, the current status of the differential decoder is displayed with
the flashing cursor on the first character. Use the arrow keys to select
ON or OFF. Press [ENTER] to execute the change.
Programs the modem for internal or external transmitter clock.
RX_Clock
On entry, the current status of the TX clock is displayed with the flashing
cursor on the first character. Use the arrow keys to select Internal or
External transmit clock. Press [ENTER] to execute the change.
Programs the modem for inverted or normal receive clock.
SWP_RACQ
On entry, the current status of the RX clock is displayed with the
flashing cursor on the first character. Use the arrow keys to select
Inverted or Normal receive clock. Press [ENTER] to execute the
change.
Programs the sweep re-acquisition mode time duration.
The time that is selected with this parameter is the time that the modem
will remain in a narrow sweep (± 10%) after acquisition has been
accomplished. After this timer runs out, the modem will return to the
normal sweep.
On entry, the current programmed setting is displayed with a flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment and decrement the digit at the
flashing cursor. Select the number of seconds for the re-acquisition
mode from 0 to 999 seconds. Press [ENTER] to execute the change.
Rev. 5
4–11
Operation
SDM-650B Satellite Modem
SWP_CNTR
Note: This window is only displayed when Fast Acquisition has been
turned ON in the Utility menu.
Programs the sweep center frequency for the directed sweep function.
The sweep center frequency may be set in the range from +25000 to
-25000 Hz.
On entry, the current programmed setting is displayed with a flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment and decrement the digit at the
flashing cursor. Select the sweep center frequency from -25000 to
+25000 Hz. Press [ENTER] to execute the change.
SWP_RNGE
When in directed sweep, the value from the sweep monitor screen
(when the modem was last locked) should be entered for the sweep
center frequency.
Note: This window is only displayed when Fast Acquisition has been
turned ON in the Utility menu.
Programs the overall travel of the sweep width range during acquisition
in the directed sweep mode. The sweep width may be set from 0 to
50000 Hz. (When set at 50000 Hz, the modem is in fast acquisition
mode.)
On entry, the current programmed setting is displayed with a flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment and decrement the digit at the
flashing cursor. Select a sweep range from 0 to 50000 Hz. Press
[ENTER] to execute the change.
SWP_DIR
When in directed sweep, the smaller the range, the faster the modem
will lock. This previous statement is true provided the sweep center
frequency is close.
Note: This window is only displayed when Fast Acquisition has been
turned ON in the Utility menu.
Programs the direction of the sweep travel in the directed sweep mode.
On entry, the current programmed setting is displayed with the flashing
cursor on the first character. Use the arrow keys to select Forward (+) or
Reverse (-). Press [ENTER] to execute the change.
4–12
Rev. 5
SDM-650B Satellite Modem
CW_Mode
(Test Mode Configuration
Option)
Operation
Programs the modem for continuous wave mode. Three modes of
operation are available:
•
•
•
Center
Dual
Offset
Center Mode:
Generates carrier at the current modulator frequency. This can be
used to measure the output frequency.
Dual Mode:
Generates a dual side-band suppressed carrier signal. Side-bands
are at one-half the symbol rate from the carrier. This is used to
check the channel balance and carrier null.
Offset Mode:
Generates a single upper side-band suppressed carrier signal. The
upper side-band is at one-quarter the symbol rate from the carrier.
This is used to check the quadrature.
On entry, the Center mode is displayed. To activate this test mode,
press [ENTER]. Use the arrow keys to select Dual or Offset mode. To
return to the Config menu, press [CLEAR].
Note: When [CLEAR] is pressed, the modem is configured to the state
it was in before CW_Mode was invoked. The transmitter is automatically
turned OFF to prevent the possible swamping of other channels. To
turn the transmitter ON, use the RF_Out function.
Rev. 5
4–13
Operation
SDM-650B Satellite Modem
BUF_clk
Programs the plesiochronous buffer output clock for:
•
•
•
•
External
Satellite
Internal
Ext_Ref
External Mode:
When this mode is selected and no clock is present at the rear of
the modem, the clock will fallback to the satellite clock. The
Satellite mode sets the output buffer clock to the satellite clock,
which is also the fallback clock.
Satellite Mode:
When selected, the doppler shift caused by the satellite will not be
removed.
Internal Mode:
This mode sets the buffer clock to operate from the modem internal
clock.
BUF_CNTR
Ext_Ref Mode:
When this mode is selected and a clock is not present, a fault will
occur. The output buffer clock will not fall back to the satellite clock.
This configuration function is used to center the buffer.
BUF_SIZE
Press [ENTER] twice to center the plesiochronous buffer.
This configuration function is used to set the size of the buffer.
On entry, the current buffer length is displayed. Use [↑] and [↓] to select
the desired buffer size. The size will be displayed in bits or milliseconds.
Use the Utility menu to select bits or milliseconds. The buffer size
ranges from 32 to 262144 bits, in steps of 16 bits, or 6 to 96 ms, in
steps of 1 ms.
Press [ENTER] to execute the change.
4–14
Rev. 5
SDM-650B Satellite Modem
Operation
4.1.4.2 Select Monitor
Refer to Table 4-3.
When the Monitor level is entered, use [←] and [→] to select the desired monitor function.
Each monitor function is displayed in real time as long as it is selected.
Function
Raw_BER
Cor_BER
Eb/N0
Swp_Freq
RXSignal
Description
Raw bit error rate.
Range: < 1.0E-4 to 2550E-4
Corrected bit error rate.
Range: < 1.0E-8 to > 1E-3
Energy(bit)/noise ratio.
Range: < 3.2 to > 9.7 dB
Sweep Monitor.
Range: -25,000 to +25,000 Hz
Receive signal level.
Range: < -60 to -30 dBm
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 2)
(See Note 1)
Notes:
1. When the decoder loses lock, no data is available, and is so indicated.
2. Sweep frequency is only displayed in the Monitor menu if Fast Acquisition
has been turned ON in the Utility menu.
Rev. 5
4–15
Operation
SDM-650B Satellite Modem
4.1.4.3 Select Faults
Refer to Table 4-4.
The Faults level is accessible from the Select menu. Faults are similar to monitor
functions, they display the current fault status of the group being displayed.
Use [←] and [→] to move between the fault groups:
•
•
•
Mod_Flts (modulator faults)
Dmd_Flts (demodulator faults)
Ceq_Flts (common equipment faults)
The current fault status is displayed on line 2 of the display in real time. Fault status is
displayed as a “+” or a “-” for each parameter monitored.
•
•
“+” indicates that a fault exists.
“-” indicates that no fault exists.
To display labels for individual faults, press [ENTER]. Use [←] and [→] to move the
flashing cursor to the fault to be identified. The label for that fault is immediately
displayed on line 1 of the display.
[CLEAR] can be used to exit this level of operation and return to the previous level.
The following sections outline the faults monitored and displayed in each group.
4–16
Rev. 5
SDM-650B Satellite Modem
Operation
4.1.4.3.1 Modulator Faults (Mod_Flts)
RF_Syn
Data Clk
TClk Syn
I-Channl
Q-Channl
AGC_levl
Module
Modulator RF synthesizer fault.
Transmit data clock activity fault.
Transmit clock synthesizer fault.
I channel activity fault.
Q channel activity fault.
Automatic gain control level fault.
Modulator module fault. Typically indicates that the modulator module is
missing or will not program.
Refer to Section 6.2 for option explanations.
4.1.4.3.2 Demodulator/Decoder Faults (Dmd_Flts)
C_Detect
RF_Syn
Data_Clk
I-Channl
Q-Channl
Dscrambl
BERthrsh
Module
Carrier detect fault. Typically indicates that the decoder is not locked.
Demodulator RF synthesizer fault.
Receive data clock activity fault.
I channel activity fault.
Q channel activity fault.
Descrambler activity fault.
Bit Error Rate threshold fault.
Demodulator/decoder module fault. Typically indicates that the
demod/decoder module is missing or will not program.
Refer to Section 6.2 for option explanations.
4.1.4.3.3 Common Equipment Faults (CEq_Flts)
Battery
-12 volt
+12 volt
+5 volt
Controlr
Intrface
Battery fault.
-12V power supply fault.
+12V power supply fault.
+5V power supply fault.
Controller fault. Typically indicates that the controller has gone through a power
ON-OFF cycle.
Interface module fault. Typically indicates that the interface module is missing
or will not program. If using an RS-422 interface module, this fault could
indicate the address jumper settings of JP4 through JP7 are not properly set.
Refer to Chapter 3 for more information.
Refer to Section 6.2 for option explanations.
Rev. 5
4–17
Operation
SDM-650B Satellite Modem
4.1.4.4 Select Stored Faults (StFaults)
Refer to Table 4-5.
The modem stores the first 10 (Flt0 to Flt9) occurrences of fault status changes in each of
the three major fault categories. Each stored fault status change is also stored with the
time and date of the occurrence. Stored faults may be viewed by entering the StFaults
level from the Select menu.
All stored faults may be cleared by executing the “CLEAR ?? StFaults” command from
the StFaults level.
Stored faults are not maintained through a controller power-on reset cycle. However, the
last known time is maintained in non-volatile RAM. Upon power-up, a common
equipment fault is logged (Flt0) with that time and date. Also on power-up, an additional
common equipment fault is logged (Flt1) to indicate the power-up time and date.
Therefore, on power-up, the power-down and power-up times are logged as common
equipment fault 0 and common equipment fault 1, respectively.
Upon entering the StFaults level, use [←] and [→] to move between the three fault groups
and the “CLEAR ?? StFaults” selections.
The time and date of the first stored fault status (Flt0) for the selected group will be
displayed alternately on line 2 of the display.
Use [↑] and [↓] to cycle through the selected group’s stored faults status (Flt0 to Flt9). To
display the fault status associated with the displayed time and date, press [ENTER]. At
this time, [←] and [→] can be used to move the flashing cursor to the individual desired
fault.
To clear the stored faults currently logged, press [ENTER] when the “CLEAR ??
StFaults” selection is displayed.
Note: Faults are stored in time sequence, with the oldest fault status change stored in Flt0
and the most recent in Flt9. Only the first 10 fault status changes are stored. All stored
faults which have not been used indicate “No Fault” on the display.
4–18
Rev. 5
SDM-650B Satellite Modem
Operation
4.1.4.5 Select Utility
Refer to Table 4-6. For additional information, refer to Section A.2.
Utility functions allows the user to:
•
•
•
•
•
•
•
•
Set the time and date of the modem real time clock
Perform a front panel lamp test
Monitor the modem address, parity, and baud rates
Offset the modulator output power
Set operational mode for TX-only, RX-only, or duplex mode
Turn Fast Acquisition ON or OFF
Set BER threshold
Assign data and code rates to the modulator and demodulator
After entering the Utility functions level, use [←] and [→] to select the desired utility
function.
Note: The selection of data/code rates in the Utility program must match the hardware
filters installed on the modulator and demodulator modules.
Time
Set real clock time.
Date
When selected, the current time in the modem’s memory is displayed. To
set the modem time, press [ENTER]. Use [←] and [→] to position the
flashing cursor over the parameter to be changed. Use [↑] and [↓] to
change the parameter to the desired value. Once the parameters are
displayed as desired, press [ENTER] to set the time.
Set real clock date.
LAMP TEST ??
Address/Parity/
Baud Rate
When selected, the current date in the modem’s memory is displayed. To
set the modem date, press [ENTER]. Use [←] and [→] to position the
flashing cursor over the parameter to be changed. Use [↑] and [↓] to
change the parameter to the desired value. Once the parameters are
displayed as desired, press [ENTER] to set the date.
Lamp test function is used to illuminate the front panel indicators for three
seconds.
Press [ENTER] to turn ON all front panel indicators for three seconds.
The current modem address, parity selection, and selected baud rate of
the modem is displayed. This is only a monitor function. No changes can
be made from this menu.
On entry, the currently set address of the modem will be displayed (0 to
255) on the first line. The currently set parity, even or odd, will be
displayed on the second line. The currently set baud rate from 110 to
9600 will also be displayed on the second line.
Rev. 5
4–19
Operation
SDM-650B Satellite Modem
POW ADJ
OP MODE
Modulator power adjust offset.
Allows the user to offset the modulator output power readout in the
Config menu. This will be the highest modulator power that will be
displayed and programmed. This feature does not actually change the
modulator power level. The function is used to change the actual reading
to display an offset value in the monitor. The modulator power offset can
be set between +20.0 to -20.0 dBm, in 0.5 dBm increments.
Operation Mode. Programs the modem operation for TX-only, RX-only,
or Duplex operation.
Fast ACQ
On entry, the flashing cursor is on the first character of the display. Use
the arrow keys to select TX-only, RX-only, or Duplex. Press [ENTER] to
execute the change. When TX-only or RX-only is selected, the
appropriate faults are masked from the Faults and StFaults menu.
Fast acquisition function.
BERT_set
Turns the fast acquisition and directed sweep function ON or OFF. When
the fast acquisition has been turned OFF, the SWP_Cntr, SWP_RNGE,
and SWP_DIR windows in the Configuration menu are disabled and do
not appear. Also, in the Monitor menu, Swp_Freq will not appear. When
turned OFF, fast acquisition does not occur.
This function is used to set the BER threshold.
If the BER threshold set is exceeded, a receive fault will be indicated by
the modem status indicators. BER threshold may be set from 1E-3 to 1E8. BER threshold may be disabled by specifying None.
BUF_CNTL
FILTERS ADJUST
4–20
On entry, the current setting of the BER threshold is displayed. Use [↑]
and [↓] to select the desired setting. Press [ENTER] to execute the
change.
ON/OFF.
This is a factory setting. The operator is not allowed to enter this
parameter without authorization from EFData Customer Support
Department. Failure to comply will result in a modem failure.
Rev. 5
SDM-650B Satellite Modem
Assign TX_Fltrs
Operation
Modulator symbol rate assignment. This function is used to view
current filter rate assignments, and to make filter rate re-assignments.
The modulator has four symbol rate filters. Filters are designated as A,
B, C, and D. Each filter is for a specific symbol rate. The data rate and
code rate for each filter must be established upon initial modulator
installation, and when circumstances indicate the need to do so.
To view the current filter assignments, press [ENTER] when the
Assign TX_FLTRS selection is displayed from the Utility Functions
menu. On line 1 of the display will be TXA, which indicates transmitter
filter A. Following TXA on line 1 will be the coder rate (1/2, 3/4, 7/8, or
BP12). On line 2 will be the data rate assigned to filter A. Use [←] and
[→] to see the assignments for filters B, C, and D (TXB, TXC, and
TXD).
To change a filter assignment, press [ENTER] when the data for that
filter is displayed. Use [←] and [→] until the flashing cursor is at the
parameter to be changed. Then use [↑] and [↓] to change that
parameter. When all changes are made, press [ENTER] to confirm the
assignment. Variable rate filters can only be programmed up to
2048 kbit/s. If a higher data rate is needed, use a fixed rate filter card.
Refer to Appendix A for more information on data rate changes and
variable rate filters.
Fixed rate filter cards can have from one to four pre-defined fixed code
and data rates installed on the filter card. If NA appears in the first line
after the transmit filter assignment, then the filter card on the modulator
does not have a filter present for that designated filter. These
assignments in the Utility menu must match the data rate on the filter
card, and cannot be changed unless the filter card is changed.
Note: These assignments are used for the selection of TXR in the
Configuration Functions menu.
Rev. 5
4–21
Operation
SDM-650B Satellite Modem
Assign RX_Fltrs
Demodulator symbol rate assignment. This function is used to view
current filter rate assignments, and to make filter rate re-assignments.
The demodulator has four symbol rate filters. Filters are designated as A,
B, C, and D. Each filter is for a specific symbol rate. The data rate and
code rate for each filter must be established upon initial demodulator
installation, and when circumstances indicate the need to do so.
To view the current filter assignments, press [ENTER] when the Assign
RX_FLTRS selection is displayed from the Utility Functions menu. On
line 1 of the display will be RXA which indicates transmitter filter A.
Following RXA on line 1 will be the coder rate (1/2, 3/4, 7/8, or BP12). On
line 2 will be the data rate assigned to filter A. Use [←] and [→] to see the
assignments for filters B, C, and D (RXB, RXC, and RXD).
To change a filter assignment, press [ENTER] when the data for that
filter is displayed. Use [←] and [→] until the flashing cursor is at the
parameter to be changed. Then use [↑] and [↓] to change that parameter.
When all changes are made, press [ENTER] to confirm the assignment.
Variable rate filters can only be programmed up to 2048 kbit/s. If a higher
data rate is needed, use a fixed rate filter card. Refer to Appendix A for
more information on data rate changes and variable rate filters.
Fixed rate filter cards can have from one to four pre-defined, fixed code
rates and data rates installed on the filter card. If NA appears in the first
line after the transmit filter assignment, then the filter card on the
demodulator does not have a filter present for that designated filter.
These assignments in the Utility menu must match the data rate on the
filter card, and cannot be changed unless the filter card is changed.
Note: These assignments are used for the selection of RXR in the
Configuration Functions menu.
4–22
Rev. 5
Chapter 5.
THEORY OF OPERATION
This chapter contains information on the following cards:
•
•
•
Modulator
Sequential decoder/demodulator processor
Demodulator
In addition, information is provided on reacquisition, fast acquisition, and the directed
sweep mode.
5.1 Modulator
The modem modulator card is a 10.25” x 14” card that fits in the top-left slot of the
modem chassis.
The modulator creates a QPSK or BPSK modulated carrier within the 50 to 90 MHz, or
100 to 180 MHz range, from the digital data stream provided by the interface card.
Several subsections make up the card:
•
•
•
•
•
•
•
•
Rev. 6
Digital interface
Scrambler/differential encoder
Convolutional encoder
I/Q Nyquist filters
Modulator
Output amplifier
RF synthesizer
Clock synthesizer
5–1
Theory of Operation
SDM-650B Satellite Modem
A block diagram of the modulator is shown in Figure 5-1.
INPUT
DATA
DATA
SCRAMBLER
DIFFERENTIAL
ENCODER
FORWARD ERROR
CORRECTION
ENCODER
I CHANNEL
NYQUIST FILTERS
POWER
COMBINER
INPUT
CLOCK
CLOCK
GENERATOR
OUTPUT
CLOCK
CLOCK
SYNTHESIZER
Q CHANNEL
NYQUIST FILTERS
MULTIPLE LOOP
SYNTHESIZER
IF
FILTER
PROCESSOR
BUS
IF OUTPUT
50 to 90 MHz
or
100 to 180 MHz
BANDPASS
FILTER
MICRO-COMPUTER
BUS INTERFACE
OUTPUT LEVEL
CONTROL
Figure 5-1. Modulator Block Diagram
Refer to Section 5.1.2 for a detailed description of the modulator.
5–2
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
5.1.1 Specifications
Modulation Type
Frequency Range
Frequency Select Method
Frequency Step Size
Frequency Stability
Channel Spacing
Phase Error
Filtering Type
Spectral Occupancy
Spurious and Harmonics
Output Power Level Range
Output Power Adjustment
Output Stability
Output Impedance
Output Return Loss
Scrambling
Differential Encoding
FEC Encoding
I/O Connector
Rev. 6
QPSK (BPSK optional)
50 to 90 MHz, or 100 to 180 MHz
Synthesized
2.5 kHz
10 PPM
0.7 times the data rate divided by the encoding rate
2.5° max
Nyquist, re-equalized
See Figure 5-2
dB at ± 0.75 symbol rate
-50 dBc minimum in-band, 40 dBc minimum out-of-band
-5 to -30 dBm
0.5 dB step size
± 0.5 dB over -5 to -25 dBm
± 1 dB over -25 to -30 dBm
75Ω (50Ω optional)
20 dB minimum
V.35 or none
2 Phase or none
Convolutional, Rate 7/8, 3/4, or 1/2
DIN, 96-pin.
5–3
Theory of Operation
SDM-650B Satellite Modem
Figure 5-2. Modulator Output Spectral Occupancy
5–4
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
5.1.2 Theory of Operation
Data that is to be transmitted is input to the digital interface of the modulator. The format
is RS-422, and includes a clock synchronous with the data. The data at this point is clean
and dejittered.
A data rate clock provided by the clock synthesizer and buffered by the digital interface
is output from the card. The frequency of this clock is programmable. The use of this
clock as the source timing signal for the link is optional.
In addition to these functions, the digital interface provides buffering of M&C signals to
the microcomputer data bus. The data for all programmable functions passes across this
interface, as well as module fault information from the modulator back to the M&C.
Faults reported include:
•
•
•
•
Synthesizers out-of-lock
AGC level
Input data clock activity
Digital I and Q channel fault
The data is delivered from the data interface to the differential encoder, and then to the
scrambler. The differential encoder is a 2-bit encoder which allows for resolution of two
of the four ambiguity states of the QPSK demodulator, or of both states of a BPSK
demodulator.
The differential encoder is programmable to ON or OFF.
The scrambler is designed according to CCITT V.35. The scrambler provides a pseudorandom characteristic to the data stream for dispersal of the transmitted energy,
independent of the data pattern.
The scrambler is programmable ON or OFF.
The data then passes to the convolutional encoder. The convolutional encoder generates
the parity bits from the input data stream that allows for error correction at the far end of
the link.
The rate of the encoder may be:
•
•
•
Rev. 6
7/8
3/4
1/2
5–5
Theory of Operation
SDM-650B Satellite Modem
For example, the rate of the encoder at 7/8 rate means 8 bits are output for every 7 bits
input. If the modulator is in the QPSK mode, the data is split into two separate data
streams to drive the in-phase and quadrature channels of the modulator.
From the encoder, the data passes to the Nyquist filters. There are two identical Nyquist
filters, one for the in-phase channel and one for the quadrature channel. Each filter is
implemented as an FIR digital filter, and provides spectral shaping and equalization.
The I and Q filtered data is applied to the modulator, which converts the data to a QPSK
modulated carrier. The spectral shape will be identical to that of the input data streams,
but double-sided about the carrier frequency.
The RF synthesizer provides the proper frequencies to convert the modulator IF to the
desired output frequency in the 50 to 90 MHz, or 100 to 180 MHz range. The frequencies
generated are locked to a single, high stability, crystal oscillator which results in an
output frequency of high stability.
The final subsection of the modulator is the output amplifier. The output amplifier takes
the low level signal from the modulator and amplifies the signal to the proper level for
output from the module.
The output amplifier contains circuitry which provides programmable control of the
output level over a 25 dB range, in 0.5 dB steps. The output amplifier also provides
power leveling to maintain the stability of the output level over time and temperature.
5–6
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
5.2 Sequential Decoder/Demodulator Processor
The modem sequential decoder/demodulator processor is a 10.25” x 14” card that fits in
the middle-left slot of the modem chassis.
The card performs five separate functions:
•
Contains the digital Costas processor which provides signals to the demodulator
board for carrier recovery and Automatic Gain Control (AGC)
•
Performs clock recovery of both the symbol clock and data clock
•
Provides the FEC function utilizing a sequential decoder
•
Provides differential decoding
•
Provides V.35 descrambling
Refer to Figure 5-3 for a block diagram of the board. Refer to Section 5.2.2 for a detailed
description of the module.
MICROCOMPUTER
BUS
MICROCOMPUTER
INTERFACE
SYNDROME SHIFT
REGISTER A
SYNDROME
INPUT
GENERATOR
AMBIGUITY
RESOLVER
PARITY
GENERATOR
V.35
DESCRAMBLER
OUTPUT
BUFFER
DIFFERENTIAL
DECODER
CHANNEL BER
DETECTOR
SYNDROM SHIFT
REGISTER B
INPUT
BUFFER
I CHANNEL
Q CHANNEL
COSTAS
PROCESSOR
RECEIVE
CLOCK
ADDRESS
GENERATOR
LOCK
DETECT
DDS
VCXO
SW EEP
RECEIVE
DATA
TIMING AND
CONTROL
RCVR
IF
PROCESS
CLOCK
CLOCK
RECOVERY
AGC
CONTROL
Figure 5-3. Decoder Block Diagram
Rev. 6
5–7
Theory of Operation
SDM-650B Satellite Modem
5.2.1 Specification
Demodulator Processor
Operating Symbol Rate Range
32 Ks/s to 2048 Ks/s
Operating Code Rate Range
7/8, 3/4, 1/2
Input Signal
11 Level Quantized I and Q
Output Signals
VCXO Drive, AGC Drive, I sign, I mag,
Q sign, Q mag, Symbol, Clock, Data Clock
Carrier Phase Error
± 3° max.
Carrier Loop Bandwidth
Software controlled
Clock Phase Error
± 5%
Clock Loop Bandwidth
Software controlled
Clock Jitter
5% P-P max.
Bit Error Rate
Maximum Data Rate
Synchronization Time
Output Fault Indicators
Raw BER Detection
Descrambling
Differential Decoding
I/O Connector
5–8
Sequential Decoder
See Chapter 1
2.1 Mbit/s (Rate 1/2)
3.2 Mbit/s (Rate 3/4 and 7/8)
19000 bits, max.
Activity detection of I and Q data
Sign bits and descrambler data
From 0 to 255 bits out of 1024 samples
V.35 or none
2 phase
DIN, -96-pin
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
5.2.2 Theory of Operation
5.2.2.1 Demodulator Processor
The demodulator processor, in conjunction with the demodulator, reconstructs the digital
data stream that was transmitted but corrupted by transmission channel impairments.
The demodulator processor accepts 11-bit quantized signals from the demodulator for
both the I and Q channels.
Two of the levels are mainly used for clock recovery. The other nine channels are used
by the Costas calculator, and in generation of the 2-bit soft decision symbols required by
the sequential decoder.
The Costas calculator generates a phase error term from the I and Q channel quantized
data. This error term is scaled by input from the M&C, then is output to the analog
portion of the loop.
The sweep voltage, which is also controlled by the M&C, is summed with the integrated
error term, and is output from the board to drive the VCXO on the demodulator.
The clock loop is contained on this card. The clock loop consists of a phase-locked loop
with a VCXO for a reference. The phase-locked loop generates a clock, four times the
desired data rate. From this clock, dividers generate the data rate clock and the symbol
rate clock.
The symbol rate clock is compared with the quantized I and Q channel data to generate a
phase error term. The error term is scaled and integrated before it drives the VCXO on
the phase locked loop, thus closing the outer loop and driving the symbol rate clock to
synchronize to the incoming symbols.
The I and Q channel data is sampled and converted to 2-bit sign-magnitude form for use
by the sequential decoder.
Rev. 6
5–9
Theory of Operation
SDM-650B Satellite Modem
5.2.2.2 Sequential Decoder
The sequential decoder works in conjunction with the convolutional encoder at the
transmitting modem to correct bit errors in the received data stream from the
demodulator. The sequential decoder processes 2-bit quantized, I and Q channel data
symbols from the demodulator. This data is assumed to be a representation of the data
transmitted, corrupted by additive white Gaussian noise.
The decoder’s task is to determine which bits have been corrupted by the transmission
channel, and correct as many as possible. The means to do this is provided by the parity
bits that the encoder adds to the input data stream prior to transmission.
The possible sequences of bits, including parity output by the encoder, is called a “code
tree.” The decoder uses the parity bits and knowledge of the code tree to determine the
most likely correct sequence of data bits for a given received sequence.
The search proceeds from a node in the code tree by choosing the branch with the highest
metric value. The highest metric value is determined by the highest probability of a
match between the received data and a possible code sequence. The branch metrics are
added to form the cumulative metric.
As long as the cumulative metric increases at each node, the decoder assumes it is on the
correct path and continues forward.
If the decoder makes a wrong decision, the cumulative metric will decrease rapidly as the
error propagates through the taps of the parity generator. In this case, the decoder tries to
back up through the data to the last node where the metric was increasing, then take the
other branch.
In a severely erred environment, the decoder will continue to search backward for a path
with an increasing metric until it either finds one, runs out of buffered data, or runs out of
time, and must deliver the next bit to the output.
The decoder processes data at a fixed rate, which is much higher than the symbol rate of
the input data. This allows the decoder to evaluate numerous paths in its search for the
most likely path during each symbol time.
Data enters the input RAM of the decoder from the demodulator processor in 2-bit soft
decision form for both I and Q channels, as shown in the block diagram (Figure 5-7).
5–10
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
The input RAM buffers the data to provide history for the backwards searches. Data from
the RAM passes through the ambiguity corrector, which compensates for the potential
90° phase ambiguity of the demodulator.
The syndrome input generator converts the 2-bit soft decision data into a single bit per
channel, and simultaneously corrects some isolated bit errors. The data is then shifted
through the syndrome shift registers, which allows the parity generator to detect bit
errors.
The resulting error signal provides the feedback to the timing and control circuitry to
allow it to direct the data along the path of the highest cumulative metric. The corrected
data is buffered through the output RAM and retiming circuit, which provides a data
stream at the constant rate of the data clock to the differential decoder and descrambler.
The data and the clock are then output from the card.
The sequential decoder provides the following built-in-test functions:
•
•
•
Activity detect on I and Q sign inputs
Activity detect of descrambler data
Raw BER detection
The sequential decoder also provides a lock detect signal to the M&C when the error rate
has dropped below a threshold level. The M&C monitors these signals and takes
appropriate action.
The raw BER count is made by comparing the input and output decoder data. The output
data contains fewer errors than the input data.
Differences in the two data can be counted to yield the raw BER. The raw BER is sent to
the M&C for further processing.
Rev. 6
5–11
Theory of Operation
SDM-650B Satellite Modem
5.2.2.2.1 Sequential Decoder BER Performance Specifications
The guaranteed BER performance curves for the sequential decoder are shown in
Figures 1-4 through 1-6. The specifications are based on 1/2, 3/4, and 7/8 rates at 100 and
1544 kbit/s.
The theoretical BER performance curves for the sequential decoder are shown in
Figures 5-4 through 5-6. The specifications are based on 1/2, 3/4, and 7/8 rates at 56 and
1544 kbit/s.
5–12
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
10-2
10-3
10-4
10-5
10-6
BER
10-7
10-8
56 kbit/s
10-9
1544 kbit/s
THEORETICAL
10-10
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
Eb/N0 (dB)
Figure 5-4. Sequential Decoder BER Performance Curves (1/2 Rate)
Rev. 6
5–13
Theory of Operation
SDM-650B Satellite Modem
10-2
10-3
10-4
10-5
10-6
BER
10-7
56 kbit/s
10-8
1544 kbit/s
THEORETICAL
10-9
10-10
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
Eb/N0 (dB)
Figure 5-5. Sequential Decoder BER Performance Curves (3/4 Rate)
5–14
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
10-2
10-3
10-4
10-5
10-6
1544 kbit/s
BER
56 kbit/s
10-7
THEORETICAL
10-8
10-9
10-10
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
Eb/N0 (dB)
Figure 5-6. Sequential Decoder BER Performance Curves (7/8 Rate)
Rev. 6
5–15
Theory of Operation
SDM-650B Satellite Modem
5.3 Demodulator
The modem demodulator card is a 10.25” x 14” card that fits in the lower-left slot of the
modem chassis.
The demodulator’s function is to accept a desired QPSK or BPSK modulated signal in the
50 to 90 MHz, or 100 to 180 MHz range. The card converts the signal to filtered
baseband in-phase and quadrature signals, which are then quantized and output from the
card.
Several subsections make up the card:
•
•
•
•
•
•
AGC amplifier
Quadrature demodulator
IF synthesizer
Nyquist filter
Baseband amplifier
Soft decision interface
Refer to Figure 5-7 for a block diagram of the demodulator. Refer to Section 5.3.2 for a
detailed description of the subsections.
IF INPUT
50-90 MHZ
OR
100-180 MHZ
AGC INPUT
PROCESSOR
BUS
LOWPASS FILTER
IF FILTER
AGC CONTROLER
MICRO-COMPUTER
BUS INTERFACE
MULTIPLE LOOP
SYNTHESIZER
QUADRATURE
VCXO
I CHANNEL
NYQUIST FILTERS
QUANTIZER
I CHANNEL
Q CHANNEL
NYQUIST FILTERS
QUANTIZER
Q CHANNEL
VCXO CONTROL
Figure 5-7. Demodulator Block Diagram
5–16
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
5.3.1 Specifications
Demodulation Type
Frequency Range
Frequency Select Method
Frequency Step Size
Channel Spacing
Input Level Desired Carrier
Input Overload
Input Impedance
Input Return Loss
Filtering
Image Rejection
Symbol Rate Range
I/O Connector
QPSK (BPSK optional)
50 to 90 MHz, or 100 to 180 MHz
Synthesized
2.5 kHz
0.7 times the data rate divided by the encoding rate
-55 to -30 dBm
0 dBm max
75Ω (50Ω optional)
20 dB minimum
Nyquist, 8 pole, 1 of 4 selectable
40 dB minimum
9.1 to 3152 Ks/s
DIN, 96-pin
5.3.2 Theory of Operation
A Costas Loop on the decoder board is used for carrier recovery.
The demodulator board provides only the I and Q channel signals, and has a VCXO
input.
The incoming modulated carrier enters the demodulator in the AGC amplifier, where the
carrier is filtered and amplified. The AGC circuit, controlled from off-card, provides
variable gain to maintain the signal level into the IF converter at a constant level over the
entire input dynamic range.
The carrier signal is converted to the fixed IF by the frequency synthesizer. The
synthesizer is programmable externally, to allow for acquisitions of carriers in the 50 to
90 MHz, or 100 to 180 MHz range.
The IF is split into two channels in the quadrature demodulator. Using an in-phase and a
quadrature carrier from a VCXO controlled externally, the quadrature demodulator
produces the I and Q channel baseband signals.
The I and Q channel baseband signals are amplified and filtered in the Nyquist filters.
These filters are matched filters to those of the transmitter, resulting in optimal detection
of the transmitted data. In addition, they effectively remove adjacent channels which
could corrupt the detection process.
The signal is amplified to the final level in the baseband amplifier. At this point, the
signal looks like the classic “eye” pattern. The signal is then quantized in the soft
decision interface and output to the card I/O connector.
Rev. 6
5–17
Theory of Operation
SDM-650B Satellite Modem
5.4 Reacquisition, Fast Acquisition, and Directed Sweep
The fast acquisition algorithm has been permanently installed in the current version of the
modem software.
The carrier should be acquired within 30 seconds, regardless of the symbol rate.
The upper limit on the symbol rate for fast acquisition is 128 kbit/s. There is no lower
limit. Fast acquisition will work in conjunction with the sweep reacquisition function.
Fast acquisition will not work concurrently with the directed sweep function. The sweep
range parameter must be set at 50000 Hz to enable fast acquisition.
If the sweep range is set at any frequency less than 50000 Hz, the modem is in the
directed sweep mode. Turning ON the directed sweep function automatically disables the
fast acquisition function.
5.4.1 Reacquisition
Normally the modem sweeps full range of ± 25 kHz during acquisition. The time it takes
to complete one full sweep cycle depends upon the symbol rate of the demodulator as
follows:
•
If the demodulator symbol rate is less than or equal to 112 kbit/s, the sweep time
is:
Sweep Time (in Seconds) = 8400/SR (symbol rate in kbit/s)
•
If the demodulator symbol rate is greater that 112 kbit/s but less than 257 kbit/s,
the sweep time is:
Sweep Time (in Seconds) = 4200/SR (symbol rate in kbit/s)
•
If the demodulator symbol rate is greater than 256 kbit/s, the sweep time is:
Sweep Time (in Seconds) = 2100/SR (symbol rate in kbit/s)
After initial acquisition (decoder locked for at least three seconds), if the carrier is lost
(decoder becomes unlocked), the modem enters the reacquisition mode.
During reacquisition, the sweep is limited to 10% of the nominal sweep range, around the
last known lock point. If reacquisition does not take place during the time set for
reacquisition (0 to 999 seconds), the modem will terminate the reacquisition mode and
begin sweeping the full range of ± 25 kHz.
5–18
Rev. 6
SDM-650B Satellite Modem
Theory of Operation
The reacquisition mode is intended to reduce the time for reacquisition at lower symbol
rates. The following guidelines should be applied when using the reacquisition mode:
•
The time specified for reacquisition must be multiples of 10% of the total
nominal sweep time. This will ensure that the modem has time to sweep across
the lock point at least once prior to termination of the reacquisition mode.
•
Add a little to the reacquisition time to account for the anticipated outage.
Example: Demodulator operating at 64 kbit/s, an anticipated outage of 2 seconds. What
should be the minimum reacquisition setting?
Sweep time = 8400/64 = 132 second (round fractions up). 10% of the total sweep
time is 13.2 seconds. Add 2 seconds to the minimum reacquisition time for the
anticipated outage.
Answer: = 15.2 seconds, round up for 16 seconds minimum.
The additional function for sweep reacquisition can be found in the Config menu of the
front panel. SWP_RACQ is the parameter used to set the minimum reacquisition time, as
described above.
5.4.2 Fast Acquisition
When fast acquisition is enabled, the fast acquisition algorithm is used for acquisition of
receive symbol rates of 128 kbit/s or lower. If the sweep range is set to less than 50 kHz,
acquisition will be dictated by the directed sweep specifications, and the fast acquisition
algorithm will not be used.
Rev. 6
5–19
Theory of Operation
SDM-650B Satellite Modem
5.4.3 Directed Sweep
The directed sweep mode was designed to rapidly acquire a carrier of known frequency
offset.
If the customer knows where the carrier is going to be, the directed sweep mode can be
much faster than the fast acquisition mode. Due to the reduced speed of the lower data
rates (up to 30 seconds in fast acquisition), the customer has the option of controlling the
sweep functions.
There are four additional functions in the front panel menu that are directly related to the
directed sweep mode:
•
Monitor function, SWP_FREQ, that detects the current sweep frequency.
•
Three functions in the Config menu that are specifically for the directed sweep
mode:
Š
Š
Š
Sweep Center
Sweep Range
Sweep Direction
These functions will only be displayed in the front panel menu when the fast acquisition
function has been turned ON in the Utility menu. Refer to Chapter 4 for further details of
the directed sweep functions.
5–20
Rev. 6
Chapter 6.
MAINTENANCE
This chapter provides information on the following:
•
•
•
•
•
System checkout
Fault isolation
Interface fault isolation
Module replacement
Module identification
6.1 System Checkout
This section should be used as an aid in setting up a modem within an earth station.
6.1.1 Modulator
The modem supplies a QPSK modulated result of the DATA I/O connector to the IF
output connector (CP1).
A typical output spectrum is shown in Figure 6-1. If the output does not resemble this
picture, refer to the fault isolation in Section 6.2 to help find the problem.
Rev. 6
6–1
Maintenance
SDM-650B Satellite Modem
The first step in turning up a carrier is to set the output frequency. This is done in the
Config menu on the front panel (refer to Chapter 4). The Config menu also allows the
operator to:
•
•
•
•
•
•
Set the output level
Turn the output ON or OFF
Set the scrambler
Differential encoder
Clock source
Gives access to the test modes for system checkout
Available test modes are:
•
•
•
RF loopback
Baseband loopback
CW
After the output frequency and level are set, the output is ready to be turned ON.
6.1.2 Demodulator
The demodulator supplies baseband data to the DATA I/O connector that is a result of the
QPSK modulated signal input at the IF input connector (CP2). Clock and data are
recovered, decoded, and descrambled from the input RF signal by the demodulator and
decoder cards.
The input to the demodulator card must be set within the proper frequency and power
level for the demodulator to lock to the signal. Refer to Figure 6-2 and Table 6-1 to check
for the proper Eb/N0 level.
Refer to Figure 6-2 for an example of a 1/2 rate carrier operating at an Eb/N0 of 9.5 dB.
The (S+N)/N is measured by taking the average level of the noise and the average level
of the top of the modem spectrum, as shown. Use this measurement for the first column
of Table 6-1. Read across the page to find the S/N and Eb/N0 for the specific code rate.
Once the demodulator has locked to the incoming signal, the Monitor menu will display:
•
•
•
•
Signal level
Raw BER
Corrected BER
Eb/N0
These functions are not displayed until the demodulator is locked to a carrier.
6–2
Rev. 6
SDM-650B Satellite Modem
Maintenance
Refer to Figure 6-3 for a typical eye pattern with noise, and Figure 6-4 for a typical eye
pattern without noise.
Refer to Figure 6-5 for a typical eye constellation with noise, and Figure 6-6 for a typical
eye constellation without noise.
If the demodulator does not lock up, refer to the fault isolation in Section 6.2.2 to help
find the problem.
Rev. 6
6–3
Maintenance
SDM-650B Satellite Modem
Figure 6-1. Typical Output Spectrum
Figure 6-2. Typical Output Spectrum
6–4
Rev. 6
SDM-650B Satellite Modem
Maintenance
Table 6-1. EFData Conversion of (S+N)/N to S/N and Eb/N0 for
Various Code Rates
(dB)
(S+N)/N
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
10.5
11.0
11.5
12.0
12.5
13.0
13.5
14.0
14.5
15.0
15.5
16.0
16.5
17.0
17.5
18.0
18.5
19.0
19.5
20.0
Rev. 6
Code Rate 1/2
S/N
Eb/N0
Code Rate 3/4
S/N
Eb/N0
Code Rate 7/8
S/N
Eb/N0
1.8
2.6
3.3
4.1
4.7
5.4
6.0
6.6
7.3
7.8
8.4
9.0
9.5
10.1
10.6
11.2
11.7
12.2
12.8
13.3
13.8
14.3
14.9
15.4
15.9
16.4
16.9
17.4
17.9
18.4
18.9
19.5
20.0
1.8
2.6
3.3
4.1
4.7
5.4
6.0
6.6
7.3
7.8
8.4
9.0
9.5
10.1
10.6
11.2
11.7
12.2
12.8
13.3
13.8
14.3
14.9
15.4
15.9
16.4
16.9
17.4
17.9
18.4
18.9
19.5
20.0
1.8
2.6
3.3
4.1
4.7
5.4
6.0
6.6
7.3
7.8
8.4
9.0
9.5
10.1
10.6
11.2
11.7
12.2
12.8
13.3
13.8
14.3
14.9
15.4
15.9
16.4
16.9
17.4
17.9
18.4
18.9
19.5
20.0
1.8
2.6
3.3
4.1
4.7
5.4
6.0
6.6
7.3
7.8
8.4
9.0
9.5
10.1
10.6
11.2
11.7
12.2
12.8
13.3
13.8
14.3
14.9
15.4
15.9
16.4
16.9
17.4
17.9
18.4
18.9
19.5
20.0
0.0
0.8
1.6
2.3
3.0
3.6
4.3
4.9
5.5
6.1
6.7
7.2
7.8
8.3
8.9
9.4
10.0
10.5
11.0
11.5
12.1
12.6
13.1
13.6
14.1
14.6
15.2
15.7
16.2
16.7
17.2
17.7
18.2
-0.6
0.2
0.9
1.6
2.3
3.0
3.6
4.2
4.8
5.4
6.0
6.6
7.1
7.7
8.2
8.8
9.3
9.8
10.3
10.9
11.4
11.9
12.4
12.9
13.5
14.0
14.5
15.0
15.5
16.0
16.5
17.0
17.5
6–5
Maintenance
SDM-650B Satellite Modem
Figure 6-3. Typical Eye Pattern with Noise
(Approximately 7.5 dB Eb/N0 )
Figure 6-4. Typical Eye Pattern without Noise
6–6
Rev. 6
SDM-650B Satellite Modem
Maintenance
Figure 6-5. Typical Eye Constellation with Noise
(Approximately 7.5 dB Eb/N0 )
Figure 6-6. Typical Eye Constellation without Noise
Rev. 6
6–7
Maintenance
SDM-650B Satellite Modem
6.1.3 Test Points
The following sections detail front panel test points, with a description of the signal that
is to be present under normal operation.
6.1.3.1 Modulator
Refer to Figure 6-7.
TPG1
TP2
Ground.
Q EYE Pattern.
TP3
Level is 2 Vp-p. The DC offset is 0V. This signal is the Q input to the QPSK
modulator. The eye pattern at this point is not equalized.
I EYE Pattern.
TP4
Level is 2 Vp-p. The DC offset is 0V. This signal is the I input to the QPSK modulator.
The eye pattern at this point is not equalized.
Q — Analog Data Eye Pattern.
TPG2
TP6
Approximately 1.4 Vp-p between eye sample points.
Ground.
I — Analog Data Eye Pattern.
TP17
Approximately 1.4 Vp-p between eye sample points.
I Channel Data.
TP18
TL level data that is output from the last register in the digital filter. The I channel
activity fault is monitoring the line.
Q Channel Data.
TP19
TTL level data that is output from the last register in the digital filter. The Q channel
activity fault is monitoring the line.
Symbol Rate Clock.
TPG6
TTL level clock that is locked to the incoming data to the interface card. This clock is
at the symbol frequency and not at the data rate. The frequency is equal to: QPSK(DATA RATE/CODE RATE)/2 BPSK-(DATA RATE/CODE RATE).
Ground.
Figure 6-7. Modulator Test Points
6–8
Rev. 6
SDM-650B Satellite Modem
Maintenance
6.1.3.2 Demodulator
Refer to Figure 6-8.
TP10
VCXO Control Voltage.
TP23
Approximately 0 to +2.5V sweep range.
Discriminator Voltage.
TPG1
TP1
Nominally +2.5V with 6 dB noise at 128 kbit/s.
Ground.
Q EYE Pattern.
TP2
TP3
TP4
Level is 1 Vp-p at the center of the eye crossing. The DC offset is about +2.4V.
Q THRS — Q channel threshold voltage, +2.9 VDC.
I THRS — I channel threshold voltage, +2.9 VDC.
I EYE Pattern.
TP5
Level is 1 Vp-p at the center of the eye crossing. The DC offset is about +2.4V.
Q CLK THRS +.
TP6
Q channel + clock threshold, +2 to +3 VDC.
Q CLK THRS -.
TP7
Q channel - clock threshold, +2 to +3 VDC.
I CLK THRS -.
TP8
I channel + clock threshold, +2 to +3 VDC.
I CLK THRS +.
I channel — clock threshold. +2 to +3 VDC.
Figure 6-8. Demodulator Test Points
Rev. 6
6–9
Maintenance
SDM-650B Satellite Modem
6.1.3.3 Sequential Decoder/Demod Card
Refer to Figure 6-9.
TPG1
TP8
Ground.
VCXO Control Voltage.
TP1
Sweeps from -2.5V to +2.5 VDC.
IMAG — I Channel Magnitude Bit.
TP2
Result of the soft bits from the soft decision interface. Transitions will occur in the
presence of noise in the RF signal.
QSGN — Q Channel Sign Bit.
TP3
Result of the hard bits from the soft decision interface. 50% duty cycle random data
is displayed.
ISGN — I Channel Sign Bit.
TP4
Result of the hard bits from the soft decision interface. 50% duty cycle random data
is displayed.
QMAG — Q Channel Magnitude Bit.
TP5
Result of the soft bits from the soft decision interface. Transitions will occur in the
presence of noise in the RF signal.
SYMBOL CLOCK.
TP9
Result of the data clock recovery loop in the demod processor section.
DECODER LOCK.
TPG2
TTL levels. TTL high indicates a locked condition. A TTL low indicates an unlocked
condition.
Ground.
Figure 6-9. Sequential Decoder/Demod Card Test Points
6–10
Rev. 6
SDM-650B Satellite Modem
Maintenance
6.2 Fault Isolation
System faults are reported in the Faults menu. Stored faults are reported in the StFaults
menu. Refer to Chapter 4 for more information.
The following sections list the system faults outlined in Chapter 4. Use the following
information to isolate a problem, and help in deciding the appropriate action to be taken.
6.2.1 Modulator Faults (Mod_Flts Menu)
Fault
RF_SYN
DATA_CLK
TCLK_SYN
Possible Problem and Action
Modulator synthesizer is faulted. This is considered a major alarm, and will
turn OFF the modulator output.
Return the modulator module for repair.
Incoming data clock activity fault. This fault is not considered a major alarm,
and will not turn OFF the modulator output.
Problem is most likely on the interface card, or external to the modem.
Check to see that the incoming data clock is present at the modem DATA
I/O connector. If data and clock are present at the DATA I/O, then replace
the interface card to clear the fault, and return for repair.
This fault is an indication that the internal clock VCO has not locked to the
incoming data clock, or the internal clock synthesizer has not locked to the
internal reference.
This is considered a major alarm, and will turn OFF the modulator output.
Check to see that the proper data rate has been set up and selected. Verify
the incoming data rate matches what has been selected in the modem.
Refer to Table 6-2 for available data rates for the modem. Refer to
INTELSAT document IESS-308 for available data rates for the SDM-308B.
Refer to INTELSAT document IESS-309 for data rates for the SDM-309B. In
the modem and SDM-308B, the data rate must reflect any overhead bit that
are added. In the SDM-309B, the internal reference is changed to account
for the IBS overhead of 16/15. Example for the modem: 1544 kbit/s with
16 kbit/s overhead channel would be programmed to operate at 1568 kbit/s
(1544K + 16K + 8K for framing). A standard modem, or a SDM-308B
operating at rev. 2, would be programmed to the input data rate. An SDM308B operating at rev. 3 would be programmed to reflect the 96 kbit/s of
overhead. A 1544 kbit/s rev. 3 IDR is programmed to 1640 kbit/s. An SDM309B would be programmed for the input data rate to the channel unit. The
modem accounts for the overhead because of the change in internal
reference. Verify the frequency of the input data clock to be within the lock
range of 100 PPM. If the inputs to the modem are all correct, then the
problem could be in one of two locations. Check the modulator first by
replacing it with a spare. If the problem still exists, replace the interface card.
When the fault has been isolated to a single card, send that card back for
repair.
Rev. 6
6–11
Maintenance
SDM-650B Satellite Modem
I-CHANNL
Q-CHANNL
Activity alarm for the I channel digital filter. This alarm is considered a major
alarm, and will turn OFF the modulator output.
An alarm in this position indicates either a fault in the scrambler, or if the
scrambler is disabled, it indicates a loss of incoming data. If the fault is active
with the scrambler turned OFF, check to see that there is input data at the
DATA I/O connector. If data is present, replace the interface card to clear the
fault and return the interface card for repair. If the fault is active with the
scrambler turned ON, replace the modulator card and return it for repair.
Activity alarm for the Q channel digital filter. This alarm is considered a major
alarm, and will turn OFF the modulator output.
AGC-LEVL
An alarm in this position indicates either a fault in the scrambler, or if the
scrambler is disabled, it indicates a loss of incoming data. If the fault is active
with the scrambler turned OFF, check to see that there is input data at the
DATA I/O connector. If data is present, replace the interface card to clear the
fault, and return the interface card for repair. If the fault is active with the
scrambler turned ON, replace the modulator card and return it for repair.
Output power level fault.
MODULE
Typically indicates that the level at the modulator output is not the level that
is programmed. Replace the modulator card and return it for repair.
Modulator module fault.
Typically indicates a problem in programming the modulator card. Check to
see that the modulator card is present and is properly seated. If the
modulator card is properly seated, this could indicate a problem in the M&C
card, or in the interface between the modulator and M&C card. Return the
defective card for repair.
6.2.2 Demodulator/Decoder Faults (Dmd_Flts Menu)
Fault
C_DETECT
Possible Problem and Action
Typically indicates loss of decoder lock.
This is the most common fault displayed in the modem. Any problem from
the input data on the modulator end of the circuit to the output of the
decoder can cause this alarm.
RF_SYN
DATA_CLK
Check first that the demodulator has an RF input at the proper frequency
and power level. Check that the demodulator data rate is properly
programmed. Refer to the fault isolation procedure for TCLK_SYN in
Section 6.2.1. Verify the frequency of the data transmitted from the
modulator is within 100 PPM. Look at the test points on the demodulator
and decoder for the eye pattern, data, and clock per Sections 6.1.3.2 and
6.1.3.3 to verify proper levels, activity, and phase.
Demodulator synthesizer is faulted.
Return the demodulator for repair.
Typically indicates a loss of lock on the reference of the demodulator clock
recovery oscillator.
Return the decoder card for repair.
6–12
Rev. 6
SDM-650B Satellite Modem
I-CHANNL
Maintenance
Indicates a loss of activity in the I channel of the quadrature demodulator.
Typically indicates a problem in the modulator side of the circuit. Check for
proper RF input to the demodulator. If the input to the demodulator is
correct, then the problem is in the baseband filter on the daughter card on
the demodulator, in the soft decision circuitry on the demodulator, or in the
decoder Costas processor. Replace either the demodulator card or the
decoder card to isolate the fault.
Q-CHANNL
Return the failed card for repair.
Indicates a loss of activity in the Q channel of the quadrature demodulator.
Typically indicates a problem in the modulator side of the circuit. Check for
proper RF input to the demodulator. If the input to the demodulator is
correct, then the problem is in the baseband filter on the daughter card on
the demodulator, in the soft decision circuitry on the demodulator, or in the
decoder Costas processor. Replace either the demodulator card or the
decoder card to isolate the fault.
DSCRAMBL
Return the failed card for repair.
Indicates loss of activity in the descrambler.
BERTHRSH
Typically indicates a loss of decoder program. Could indicate a problem in
the M&C card, or a problem in the communication between the M&C and
decoder.
Indication that the preset BER threshold has been exceeded.
MODULE
Setting of this alarm is done in the Utility menu. This alarm is a function of
the corrected BER reading on the front panel.
Demodulator module fault. Indicates a problem in programming the
demodulator card.
Check to see that the demodulator card and the decoder card are present
and are properly seated. If the cards are properly seated, this could indicate
a problem in the M&C card, or in the interface between the decoder card
and M&C card. Return the defective card for repair.
Rev. 6
6–13
Maintenance
SDM-650B Satellite Modem
6.2.3 Common Equipment Faults (CEq_Flts Menu)
Fault
BATTERY
Possible Problem and Action
M&C battery voltage fault.
-12 Volt
Indicates a low voltage in the memory battery. Typically will be active when a
modem is first turned ON. Allow the modem to charge up the battery before
any other action is taken. Charge time is 5 to 8 hours, depending on how
long the modem has been powered down.
-12V power supply fault.
+12 Volt
Indicates a high or low voltage condition. Level is ± 5%. Check for a short on
the -12V line on the motherboard, or a short on the -12V line of any of the
plug-in boards. To gain access to the rear of the motherboard, remove the
rear panel cover. Refer to Figure 6-10 for location of the -12V on the
motherboard. Return the faulty plug-in board or replace the chassis power
supply.
+12V power supply fault.
+5V Volt
Indicates a high or low voltage condition. Level is ± 5%. Check for a short on
the +12V line on the motherboard, or a short on the +12V line of any of the
plug-in boards. To gain access to the rear side of the motherboard, remove
the rear panel cover. Refer to Figure 6-10 for location of the +12V on the
motherboard. Return the faulty plug-in board or replace the chassis power
supply.
+5V power supply fault.
Use the same procedure as with -12V fault.
Indicates a high or low voltage condition. Level is ± 5%. Check for a short on
the +5V line on the motherboard, or a short on the +5V line of any of the
plug-in boards. To gain access to the rear of the motherboard, remove the
rear panel cover. Refer to Figure 6-10 for location of the +5V on the
motherboard. Return the faulty plug-in board or replace the chassis power
supply.
TXC-LOSS
The +5V supply requires a minimum load of 1A. This is accomplished with
the M&C card and one other card being plugged into the chassis.
This is an indicator for reporting the loss of incoming DS1 data.
CONTROLR
This alarm is active only when the DS1 interface is installed.
Controller fault. Indicates a loss of power in the M&C card.
INTRFACE
This fault is shown only in the StFaults menu.
Interface module fault. Indicates a problem in programming the interface
card.
Check to see that the interface card is present and is properly seated. If the
card is properly seated, this could indicate a problem in the M&C card, or in
the interface between the interface card and M&C card. Return the defective
card for repair.
6–14
Rev. 6
SDM-650B Satellite Modem
Maintenance
6.3 Interface Fault Isolation
Stored faults for the interface are reported in the StFaults menu (refer to Chapter 4).
The following sections list the interface faults. All other faults are discussed in Section
6.2.
6.3.1 Transmit Faults (TX_INTF)
The faults listed below are only displayed when the ASYNC overhead channel unit is
installed.
Fault
TX_PLL
CLK_ACT
Possible Problem and Action
Indicates a loss of lock on the reference of the interface transmit clock recovery
oscillator.
Return the interface card for repair.
Loss of activity on the selected transmit clock source.
The modem will fallback to the internal SCT clock source with an accuracy
of 10-5.
Rev. 6
6–15
Maintenance
SDM-650B Satellite Modem
6.3.2 Receive Faults (RX_INTF)
The faults listed below are only displayed when the ASYNC overhead channel unit is
installed.
Fault
BUF_UNFL
Possible Problem and Action
Buffer Underflow. The plesiochronous buffer has underflowed.
BUF_OVFL
As buffer underflow is normally a momentary fault (there are clock problems if
this is continuously present). This is included in this section to be consistent
with the fault reporting system and be correctly registered in the stored fault
memory. The time and date of the last 10 receive OFU faults are stored in
battery-backed memory as an aid to troubleshooting. The interval between
stored overflow/underflow events can be used to determine the accuracy of
the relative clock.
Buffer Overflow. The plesiochronous buffer has overflowed.
RX_PLL
BUFF_CLK
MUX_Lock
As buffer overflow is normally a momentary fault, there will be clock problems
if this is continuously present. This is included in this section to be consistent
with the fault reporting system and be correctly registered in the stored fault
memory. The time and date of the last 10 receive OFU faults are stored in
battery-backed memory as an aid to troubleshooting. The interval between
stored overflow/underflow events can be used to determine the accuracy of
the relative clock.
Indicates a loss of lock on the reference of the interface receive clock
recovery oscillator.
Return the interface card for repair.
Loss of activity on the selected buffer clock source.
The modem will fallback to the satellite clock.
Demultiplexer Synchronization Lock Fault. This fault means that the
demultiplexer is unable to maintain valid frame and multiframe alignment.
The usual cause is invalid or absent receive data. This is a major (prompt)
alarm. It will cause insertion of receive Alarm Indication Signal (all 1s) and
switchover will be attempted. This fault is to be sent as a backward alarm to
the distant end. This fault will occur when no carrier is present, but will
probably never occur with a correct signal.
6–16
Rev. 6
SDM-650B Satellite Modem
Maintenance
Table 6-2. Programmable Data Rates for the Variable Rate SDM-650B Modem
20.4
22.0
23.6
25.4
26.8
27.8
28.8
29.8
30.8
31.8
32.8
33.8
34.8
35.8
36.8
37.8
38.8
39.8
40.8
41.8
42.8
43.8
44.8
45.8
46.8
47.8
48.8
49.8
50.8
54.5
59.5
64.5
69.5
74.5
79.5
84.5
89.5
94.5
99.5
104.5
109.5
114.5
119.5
124.5
129.5
134.5
139.5
144.5
149.5
154.5
159.5
164.5
169.5
174.5
179.5
184.5
189.5
194.5
199.5
Rev. 6
20.5
22.2
23.8
25.5
26.9
27.9
28.9
29.9
30.9
31.9
32.9
33.9
34.9
35.9
36.9
37.9
38.9
39.9
40.9
41.9
42.9
43.9
44.9
45.9
46.9
47.9
48.9
49.9
50.9
55.0
60.0
65.0
70.0
75.0
80.0
85.0
90.0
95.0
100.0
105.0
110.0
115.0
120.0
125.0
130.0
135.0
140.0
145.0
150.0
155.0
160.0
165.0
170.0
175.0
180.0
185.0
190.0
195.0
200.0
20.6
22.4
24.0
25.6
27.0
28.0
29.0
30.0
31.0
32.0
33.0
34.0
35.0
36.0
37.0
38.0
39.0
40.0
41.0
42.0
43.0
44.0
45.0
46.0
47.0
48.0
49.0
50.0
51.0
55.5
60.5
65.5
70.5
75.5
80.5
85.5
90.5
95.5
100.5
105.5
110.5
115.5
120.5
125.5
130.5
135.5
140.5
145.5
150.5
155.5
160.5
165.5
170.5
175.5
180.5
185.5
190.5
195.5
200.5
19.2
20.8
22.5
24.2
25.8
27.1
28.1
29.1
30.1
31.1
32.1
33.1
34.1
35.1
36.1
37.1
38.1
39.1
40.1
41.1
42.1
43.1
44.1
45.1
46.1
47.1
48.1
49.1
50.1
51.1
56.0
61.0
66.0
71.0
76.0
81.0
86.0
91.0
96.0
101.0
106.0
111.0
116.0
121.0
126.0
131.0
136.0
141.0
146.0
151.0
156.0
161.0
166.0
171.0
176.0
181.0
186.0
191.0
196.0
201.0
19.4
21.0
22.6
24.4
26.0
27.2
28.2
29.2
30.2
31.2
32.2
33.2
34.2
35.2
36.2
37.2
38.2
39.2
40.2
41.2
42.2
43.2
44.2
45.2
46.2
47.2
48.2
49.2
50.2
51.5
56.5
61.5
66.5
71.5
76.5
81.5
86.5
91.5
96.5
101.5
106.5
111.5
116.5
121.5
126.5
131.5
136.5
141.5
146.5
151.5
156.5
161.5
166.5
171.5
176.5
181.5
186.5
191.5
196.5
201.5
19.5
21.2
22.8
24.5
26.2
27.3
28.3
29.3
30.3
31.3
32.3
33.3
34.3
35.3
36.3
37.3
38.3
39.3
40.3
41.3
42.3
43.3
44.3
45.3
46.3
47.3
48.3
49.3
50.3
52.0
57.0
62.0
67.0
72.0
77.0
82.0
87.0
92.0
97.0
102.0
107.0
112.0
117.0
122.0
127.0
132.0
137.0
142.0
147.0
152.0
157.0
162.0
167.0
172.0
177.0
182.0
187.0
192.0
197.0
202.0
19.6
21.4
23.0
24.6
26.4
27.4
28.4
29.4
30.4
31.4
32.4
33.4
34.4
35.4
36.4
37.4
38.4
39.4
40.4
41.4
42.4
43.4
44.4
45.4
46.4
47.4
48.4
49.4
50.4
52.5
57.5
62.5
67.5
72.5
77.5
82.5
87.5
92.5
97.5
102.5
107.5
112.5
117.5
122.5
127.5
132.5
137.5
142.5
147.5
152.5
157.5
162.5
167.5
172.5
177.5
182.5
187.5
192.5
197.5
202.5
19.8
21.5
23.2
24.8
26.5
27.5
28.5
29.5
30.5
31.5
32.5
33.5
34.5
35.5
36.5
37.5
38.5
39.5
40.5
41.5
42.5
43.5
44.5
45.5
46.5
47.5
48.5
49.5
50.5
53.0
58.0
63.0
68.0
73.0
78.0
83.0
88.0
93.0
98.0
103.0
108.0
113.0
118.0
123.0
128.0
133.0
138.0
143.0
148.0
153.0
158.0
163.0
168.0
173.0
178.0
183.0
188.0
193.0
198.0
203.0
20.0
21.6
23.4
25.0
26.6
27.6
28.6
29.6
30.6
31.6
32.6
33.6
34.6
35.6
36.6
37.6
38.6
39.6
40.6
41.6
42.6
43.6
44.6
45.6
46.6
47.6
48.6
49.6
50.6
53.5
58.5
63.5
68.5
73.5
78.5
83.5
88.5
93.5
98.5
103.5
108.5
113.5
118.5
123.5
128.5
133.5
138.5
143.5
148.5
153.5
158.5
163.5
168.5
173.5
178.5
183.5
188.5
193.5
198.5
203.5
20.2
21.8
23.5
25.2
26.7
27.7
28.7
29.7
30.7
31.7
32.7
33.7
34.7
35.7
36.7
37.7
38.7
39.7
40.7
41.7
42.7
43.7
44.7
45.7
46.7
47.7
48.7
49.7
50.7
54.0
59.0
64.0
69.0
74.0
79.0
84.0
89.0
94.0
99.0
104.0
109.0
114.0
119.0
124.0
129.0
134.0
139.0
144.0
149.0
154.0
159.0
164.0
169.0
174.0
179.0
184.0
189.0
194.0
199.0
204.0
6–17
Maintenance
204.5
208.5
212.5
216.5
220.5
224.5
228.5
232.5
236.5
240.5
244.5
248.5
252.5
257.0
263.0
270.0
276.8
283.2
290.0
297.0
303.0
310.0
316.8
323.2
330.0
337.0
343.0
350.0
356.8
363.2
370.0
377.0
383.0
390.0
396.8
403.2
410.0
417.0
423.0
430.0
436.8
443.2
450.0
457.0
463.0
470.0
476.8
483.2
490.0
497.0
503.0
510.0
518.4
529.6
539.2
548.8
558.4
569.6
579.2
588.8
598.4
6–18
SDM-650B Satellite Modem
204.8
209.0
212.8
217.0
220.8
225.0
228.8
233.0
236.8
241.0
244.8
249.0
252.8
257.6
264.0
270.4
277.0
284.0
291.0
297.6
304.0
310.4
317.0
324.0
331.0
337.6
344.0
350.4
357.0
364.0
371.0
377.6
384.0
390.4
397.0
404.0
411.0
417.6
424.0
430.4
437.0
444.0
451.0
457.6
464.0
470.4
477.0
484.0
491.0
497.6
504.0
510.4
520.0
530.0
540.0
550.0
560.0
570.0
580.0
590.0
600.0
205.0
209.5
213.0
217.5
221.0
225.5
229.0
233.5
237.0
241.5
245.0
249.5
253.0
258.0
265.0
271.0
278.0
284.8
291.2
298.0
305.0
311.0
318.0
324.8
331.2
338.0
345.0
351.0
358.0
364.8
371.2
378.0
385.0
391.0
398.0
404.8
411.2
418.0
425.0
431.0
438.0
444.8
451.2
458.0
465.0
471.0
478.0
484.8
491.2
498.0
505.0
511.0
521.6
531.2
540.8
550.4
561.6
571.2
580.8
590.4
601.6
205.5
209.6
213.5
217.6
221.5
225.6
229.5
233.6
237.5
241.6
245.5
249.6
253.5
259.0
265.6
272.0
278.4
285.0
292.0
299.0
305.6
312.0
318.4
325.0
332.0
339.0
345.6
352.0
358.4
365.0
372.0
379.0
385.6
392.0
398.4
405.0
412.0
419.0
425.6
432.0
438.4
445.0
452.0
459.0
465.6
472.0
478.4
485.0
492.0
499.0
505.6
512.0
522.0
532.0
542.0
552.0
562.0
572.0
582.0
592.0
602.0
206.0
210.0
214.0
218.0
222.0
226.0
230.0
234.0
238.0
242.0
246.0
250.0
254.0
259.2
266.0
273.0
279.0
286.0
292.8
299.2
306.0
313.0
319.0
326.0
332.8
339.2
346.0
353.0
359.0
366.0
372.8
379.2
386.0
393.0
399.0
406.0
412.8
419.2
426.0
433.0
439.0
446.0
452.8
459.2
466.0
473.0
479.0
486.0
492.8
499.2
506.0
513.6
523.2
532.8
542.4
553.6
563.2
572.8
582.4
593.6
603.2
206.4
210.5
214.4
218.5
222.4
226.5
230.4
234.5
238.4
242.5
246.4
250.5
254.4
260.0
267.0
273.6
280.0
286.4
293.0
300.0
307.0
313.6
320.0
326.4
333.0
340.0
347.0
353.6
360.0
366.4
373.0
380.0
387.0
393.6
400.0
406.4
413.0
420.0
427.0
433.6
440.0
446.4
453.0
460.0
467.0
473.6
480.0
486.4
493.0
500.0
507.0
514.0
524.0
534.0
544.0
554.0
564.0
574.0
584.0
594.0
604.0
206.5
211.0
214.5
219.0
222.5
227.0
230.5
235.0
238.5
243.0
246.5
251.0
254.5
260.8
267.2
274.0
281.0
287.0
294.0
300.8
307.2
314.0
321.0
327.0
334.0
340.8
347.2
354.0
361.0
367.0
374.0
380.8
387.2
394.0
401.0
407.0
414.0
420.8
427.2
434.0
441.0
447.0
454.0
460.8
467.2
474.0
481.0
487.0
494.0
500.8
507.2
515.2
524.8
534.4
545.6
555.2
564.8
574.4
585.6
595.2
604.8
207.0
211.2
215.0
219.2
223.0
227.2
231.0
235.2
239.0
243.2
247.0
251.2
255.0
261.0
268.0
275.0
281.6
288.0
294.4
301.0
308.0
315.0
321.6
328.0
334.4
341.0
348.0
355.0
361.6
368.0
374.4
381.0
388.0
395.0
401.6
408.0
414.4
421.0
428.0
435.0
441.6
448.0
454.4
461.0
468.0
475.0
481.6
488.0
494.4
501.0
508.0
516.0
526.0
536.0
546.0
556.0
566.0
576.0
586.0
596.0
606.0
207.5
211.5
215.5
219.5
223.5
227.5
231.5
235.5
239.5
243.5
247.5
251.5
255.5
262.0
268.8
275.2
282.0
289.0
295.0
302.0
308.8
315.2
322.0
329.0
335.0
342.0
348.8
355.2
362.0
369.0
375.0
382.0
388.8
395.2
402.0
409.0
415.0
422.0
428.8
435.2
442.0
449.0
455.0
462.0
468.8
475.2
482.0
489.0
495.0
502.0
508.8
516.8
526.4
537.6
547.2
556.8
566.4
577.6
587.2
596.8
606.4
208.0
212.0
216.0
220.0
224.0
228.0
232.0
236.0
240.0
244.0
248.0
252.0
256.0
262.4
269.0
276.0
283.0
289.6
296.0
302.4
309.0
316.0
323.0
329.6
336.0
342.4
349.0
356.0
363.0
369.6
376.0
382.4
389.0
396.0
403.0
409.6
416.0
422.4
429.0
436.0
443.0
449.6
456.0
462.4
469.0
476.0
483.0
489.6
496.0
502.4
509.0
518.0
528.0
538.0
548.0
558.0
568.0
578.0
588.0
598.0
608.0
Rev. 6
SDM-650B Satellite Modem
609.6
619.2
628.8
638.4
649.6
659.2
668.8
678.4
689.6
699.2
708.8
718.4
729.6
739.2
748.8
758.4
769.6
779.2
788.8
798.4
809.6
820.0
840.0
860.0
880.0
900.0
920.0
940.0
960.0
980.0
1000.0
1020.0
1056.0
1096.0
1136.0
1176.0
1216.0
1256.0
1296.0
1336.0
1376.0
1416.0
1456.0
1496.0
1536.0
1576.0
1616.0
1656.0
1696.0
1736.0
1776.0
1816.0
1856.0
1896.0
1936.0
1976.0
2016.0
2064.0
2144.0
2224.0
2304.0
Rev. 6
610.0
620.0
630.0
640.0
650.0
660.0
670.0
680.0
690.0
700.0
710.0
720.0
730.0
740.0
750.0
760.0
770.0
780.0
790.0
800.0
810.0
822.0
842.0
862.0
882.0
902.0
922.0
942.0
962.0
982.0
1002.0
1022.0
1060.0
1100.0
1140.0
1180.0
1220.0
1260.0
1300.0
1340.0
1380.0
1420.0
1460.0
1500.0
1540.0
1580.0
1620.0
1660.0
1700.0
1740.0
1780.0
1820.0
1860.0
1900.0
1940.0
1980.0
2020.0
2072.0
2152.0
2232.0
2312.0
Maintenance
611.2
620.8
630.4
641.6
651.2
660.8
670.4
681.6
691.2
700.8
710.4
721.6
731.2
740.8
750.4
761.6
771.2
780.8
790.4
801.6
811.2
824.0
844.0
864.0
884.0
904.0
924.0
944.0
964.0
984.0
1004.0
1024.0
1064.0
1104.0
1144.0
1184.0
1224.0
1264.0
1304.0
1344.0
1384.0
1424.0
1464.0
1504.0
1544.0
1584.0
1624.0
1664.0
1704.0
1744.0
1784.0
1824.0
1864.0
1904.0
1944.0
1984.0
2024.0
2080.0
2160.0
2240.0
2320.0
612.0
622.0
632.0
642.0
652.0
662.0
672.0
682.0
692.0
702.0
712.0
722.0
732.0
742.0
752.0
762.0
772.0
782.0
792.0
802.0
812.0
826.0
846.0
866.0
886.0
906.0
926.0
946.0
966.0
986.0
1006.0
1028.0
1068.0
1108.0
1148.0
1188.0
1228.0
1268.0
1308.0
1348.0
1388.0
1428.0
1468.0
1508.0
1548.0
1588.0
1628.0
1668.0
1708.0
1748.0
1788.0
1828.0
1868.0
1908.0
1948.0
1988.0
2028.0
2088.0
2168.0
2248.0
2328.0
612.8
622.4
633.6
643.2
652.8
662.4
673.6
683.2
692.8
702.4
713.6
723.2
732.8
742.4
753.6
763.2
772.8
782.4
793.6
803.2
812.8
828.0
848.0
868.0
888.0
908.0
928.0
948.0
968.0
988.0
1008.0
1032.0
1072.0
1112.0
1152.0
1192.0
1232.0
1272.0
1312.0
1352.0
1392.0
1432.0
1472.0
1512.0
1552.0
1592.0
1632.0
1672.0
1712.0
1752.0
1792.0
1832.0
1872.0
1912.0
1952.0
1992.0
2032.0
2096.0
2176.0
2256.0
2336.0
614.0
624.0
634.0
644.0
654.0
664.0
674.0
684.0
694.0
704.0
714.0
724.0
734.0
744.0
754.0
764.0
774.0
784.0
794.0
804.0
814.0
830.0
850.0
870.0
890.0
910.0
930.0
950.0
970.0
990.0
1010.0
1036.0
1076.0
1116.0
1156.0
1196.0
1236.0
1276.0
1316.0
1356.0
1396.0
1436.0
1476.0
1516.0
1556.0
1596.0
1636.0
1676.0
1716.0
1756.0
1796.0
1836.0
1876.0
1916.0
1956.0
1996.0
2036.0
2104.0
2184.0
2264.0
2344.0
614.4
625.6
635.2
644.8
654.4
665.6
675.2
684.8
694.4
705.6
715.2
724.8
734.4
745.6
755.2
764.8
774.4
785.6
795.2
804.8
814.4
832.0
852.0
872.0
892.0
912.0
932.0
952.0
972.0
992.0
1012.0
1040.0
1080.0
1120.0
1160.0
1200.0
1240.0
1280.0
1320.0
1360.0
1400.0
1440.0
1480.0
1520.0
1560.0
1600.0
1640.0
1680.0
1720.0
1760.0
1800.0
1840.0
1880.0
1920.0
1960.0
2000.0
2040.0
2112.0
2192.0
2272.0
2352.0
616.0
626.0
636.0
646.0
656.0
666.0
676.0
686.0
696.0
706.0
716.0
726.0
736.0
746.0
756.0
766.0
776.0
786.0
796.0
806.0
816.0
834.0
854.0
874.0
894.0
914.0
934.0
954.0
974.0
994.0
1014.0
1044.0
1084.0
1124.0
1164.0
1204.0
1244.0
1284.0
1324.0
1364.0
1404.0
1444.0
1484.0
1524.0
1564.0
1604.0
1644.0
1684.0
1724.0
1764.0
1804.0
1844.0
1884.0
1924.0
1964.0
2004.0
2044.0
2120.0
2200.0
2280.0
2360.0
617.6
627.2
636.8
646.4
657.6
667.2
676.8
686.4
697.6
707.2
716.8
726.4
737.6
747.2
756.8
766.4
777.6
787.2
796.8
806.4
817.6
836.0
856.0
876.0
896.0
916.0
936.0
956.0
976.0
996.0
1016.0
1048.0
1088.0
1128.0
1168.0
1208.0
1248.0
1288.0
1328.0
1368.0
1408.0
1448.0
1488.0
1528.0
1568.0
1608.0
1648.0
1688.0
1728.0
1768.0
1808.0
1848.0
1888.0
1928.0
1968.0
2008.0
2048.0
2128.0
2208.0
2288.0
2368.0
618.0
628.0
638.0
648.0
658.0
668.0
678.0
688.0
698.0
708.0
718.0
728.0
738.0
748.0
758.0
768.0
778.0
788.0
798.0
808.0
818.0
838.0
858.0
878.0
898.0
918.0
938.0
958.0
978.0
998.0
1018.0
1052.0
1092.0
1132.0
1172.0
1212.0
1252.0
1292.0
1332.0
1372.0
1412.0
1452.0
1492.0
1532.0
1572.0
1612.0
1652.0
1692.0
1732.0
1772.0
1812.0
1852.0
1892.0
1932.0
1972.0
2012.0
2056.0
2136.0
2216.0
2296.0
2376.0
6–19
Maintenance
2384.0
2464.0
2544.0
2624.0
2704.0
2784.0
2864.0
2944.0
3024.0
3104.0
3184.0
3264.0
3344.0
3424.0
3504.0
3584.0
Notes:
1.
2.
3.
4.
5.
SDM-650B Satellite Modem
2392.0
2472.0
2552.0
2632.0
2712.0
2792.0
2872.0
2952.0
3032.0
3112.0
3192.0
3272.0
3352.0
3432.0
3512.0
2400.0
2480.0
2560.0
2640.0
2720.0
2800.0
2880.0
2960.0
3040.0
3120.0
3200.0
3280.0
3360.0
3440.0
3520.0
2408.0
2488.0
2568.0
2648.0
2728.0
2808.0
2888.0
2968.0
3048.0
3128.0
3208.0
3288.0
3368.0
3448.0
3528.0
2416.0
2496.0
2576.0
2656.0
2736.0
2816.0
2896.0
2976.0
3056.0
3136.0
3216.0
3296.0
3376.0
3456.0
3536.0
2424.0
2504.0
2584.0
2664.0
2744.0
2824.0
2904.0
2984.0
3064.0
3144.0
3224.0
3304.0
3384.0
3464.0
3544.0
2432.0
2512.0
2592.0
2672.0
2752.0
2832.0
2912.0
2992.0
3072.0
3152.0
3232.0
3312.0
3392.0
3472.0
3552.0
2440.0
2520.0
2600.0
2680.0
2760.0
2840.0
2920.0
3000.0
3080.0
3160.0
3240.0
3320.0
3400.0
3480.0
3560.0
2448.0
2528.0
2608.0
2688.0
2768.0
2848.0
2928.0
3008.0
3088.0
3168.0
3248.0
3328.0
3408.0
3488.0
3568.0
2456.0
2536.0
2616.0
2696.0
2776.0
2856.0
2936.0
3016.0
3096.0
3176.0
3256.0
3336.0
3416.0
3496.0
3576.0
Rates below 48 kbit/s are BPSK only.
Rates above 2.048 Mbit/s available in single rate modem only.
Maximum 1/2 rate is 2048 kbit/s.
Maximum 3/4 rate is 3072 kbit/s.
Maximum 7/8 rate is 3584 kbit/s.
POWER SUPPLY TEST POINTS
DATA
I/OI
IF OUTPUT
GND
REMOTE
J8
IF INPUT
FAULT
POWER SUPPLY TEST POINTS
Figure 6-10. Rear View Without Cover
6–20
Rev. 6
SDM-650B Satellite Modem
Maintenance
6.4 Module Replacement
The modem cards are plug-in cards that can be replaced by removing the defective card,
and reinserting the replacement. Card ejectors are available for use in removing the cards.
Note: On the interface card, there are additional screws on the rear panel that need to be
removed before the interface card is removed. These screws must be reinstalled after the
replacement card is inserted.
The power supply in the modem is attached to the modem chassis. For repair of the
power supply module, it is recommended that all plug-in cards be removed, and the
chassis (with the power supply installed) be sent back to the factory for repair.
For instructions on changing data rate cards or software upgrades, refer to Appendix A.
6.5 Module Identification
The modem cards each have an assembly number marked on the board. The latest
revision and serial number are stamped on the board. EFData tracks hardware by
assembly, revision, and serial number.
Data rate dependent hardware is labeled with the associated symbol rate on a label on the
board.
When replacing a plug-in module, care must be taken to ensure that the proper daughter
card is used.
Refer to the individual sections on each module for location of the configuration
identification.
Refer to Table 6-3 for a list of part numbers and descriptions of various modules used in
the modem.
Rev. 6
6–21
Maintenance
SDM-650B Satellite Modem
Table 6-3. EFData Part Numbers for SDM-650B Modules
Modulators Base Part Number — AS/0773
Description
SDM-650B, EFData Filtering
SDM-650F, FDC Comp Filtering
SDM-650B, STM Filtering
SDM-650F, FDC Filtering, with 1X10-7 Reference
SDM-650F, FDC Filtering, Aydin Data Rate Crystal
SDM-650B, EFData Filtering, 50Ω Output
Demodulators Base Part Number — AS/0778
Dash #
Description
1
SDM-650B, 70/140 MHz, 75Ω
6
SDM-650B, 70/140 MHz, 50Ω
Decoders Base Part Number — AS/0365
Dash #
Description
1
SDM-650B (Std, F, C), 70/140 MHz (with GND rails)
2
SDM-650B (Std, F, C), 70 MHz (without GND rails)
3
SDM-650B w/ASYNC Interface (offset crystal)
4
SDM-650F, Aydin Data Rate Crystal
Interface and Filter Cards
Part #
Description
AS/0627-2
V.35 Interface
AS/0627-3
RS-422/RS-449, and MIL-STD-188-114
AS/0627-8
RS-232 Interface
AS/0569
DS1 Interface
AS/0679
G.703 Balanced Interface
AS/1289-1
Asynchronous Overhead Channel Unit without AUPC
(RS-422, and MIL-STD-188-114)
AS/1289-2
V.35 Asynchronous Overhead Channel Unit without
AUPC
AS/1289-3
G.703 Asynchronous Overhead Channel Unit without
AUPC
AS/0930-1
Modulator Daughter Filter Card (Variable Rate)
AS/0715-X (See note)
Modulator Daughter Filter Card (Fixed Rate)
AS/0929-1
Demodulator Daughter Filter Card (Variable Rate)
AS/0929-3
Fairchild Compatible Demod Daughter Filter Card
AS/0362-X (See note)
Demodulator Daughter Filter Card (Fixed Rate)
AS/0698-X (See note)
Demodulator Daughter Filter Card (Fixed Rate)
Dash #
1
3
5
9
12
14
Note: X = 1 to 4, the number of filters installed on a fixed rate filter card.
6–22
Rev. 6
Appendix A.
DATA RATES AND FILTERS
The modem will operate at data rates from 19.2 kbit/s to 3.584 Mbit/s. Data rates from
19.2 to 48 kbit/s are 1/2 rate BPSK only.
Variable rate filters can operate from 19.2 to 2048 kbit/s. Fixed rate filters allow
operation from 19.2 to 3584 kbit/s.
This appendix covers:
•
•
•
Data rate change instructions for fixed rate and variable rate filters
Differences between a fixed rate filter and a variable rate filter
Modem configuration for each filter type
A.1 Fixed Rate Filters
A.1.1 Data Rate Change Instructions
1. Turn OFF modem power switch.
2. Remove the modulator card (AS/0773) by using the black card ejectors.
3. Remove the two screws securing the daughter card (AS/0715) with a Phillips
screwdriver. See Figure A-1 for location of the hardware.
4. Remove the daughter card from the modulator.
Rev. 6
A–1
Data Rates and Filters
SDM-650B Satellite Modem
VARIABLE RATE
MODULATOR FILTER
MOUNTING
HARDWARE (2)
FIXED RATE
MODULATOR FILTER
MODULATOR
Figure A-1. Modulator Filter Card Change
5. Install the replacement daughter card, and ensure both screw holes line up with
the mounting hardware. See Figure A-1.
If the filter is installed in the wrong position, the daughter card will
be damaged.
CAUTION
A–2
Rev. 6
SDM-650B Satellite Modem
Data Rates and Filters
6. Re-install the daughter board hold-down screws (Figure A-1). Re-insert the
modulator into the chassis.
7. Remove the demodulator card (AS/0778) using the white card ejectors.
8. With a Phillips screwdriver, remove the four screws holding down the daughter
card. See Figure A-2 for location of the hardware.
9. Remove the daughter card (AS/0362) from the demodulator.
10. Install the replacement daughter card (AS/0362) so that:
a. J1 on the daughter card lines up with J2 on the demodulator card.
b. J2 on the daughter card lines up with J3 on the demodulator card.
c. All four hold-down screws line up.
See Figure A-2.
If the filter is installed in the wrong position, the daughter card will
be damaged.
CAUTION
11. Re-install the daughter board hold-down screws (Figure A-2), and re-insert the
demodulator into the modem chassis.
12. Remove the M&C board, and remove JP6 (battery ON/OFF). Short the leads of
capacitor C12. Replace the battery jumper to the ON position, and re-insert the
M&C card into the modem.
13. Turn ON the power switch.
14. Go to the Utility menu on the front panel, and program the time, day, TXA, TXB,
TXC, TXD, RXA, RXB, RXC, and RXD to the new data/code rates.
Note: The data/code rate assignment in the Utility menu must match the filter
assignment on the daughter card. Each daughter card is labeled with the filter
assignment (A, B, C, and D) and associated symbol rate. Example: The label for
a 64 kbit/s, 7/8 rate, QPSK filter is 36.57.
15. Go to the Config menu on the front panel and select the desired TX and RX rate.
Turn ON the RF output.
The hardware change is complete.
Rev. 6
A–3
Data Rates and Filters
SDM-650B Satellite Modem
DEMODULATOR
ASSEMBLY AND
REVISION NUMBER
DATA RATE
INFORMATION
SERIAL
NUMBER
VARIABLE RATE DEMODULATOR FILTER
FIXED RATE DEMODULATOR FILTER
Figure A-2. Demodulator Filter Card Change
A–4
Rev. 6
SDM-650B Satellite Modem
Data Rates and Filters
A.1.2 Hardware Configuration
This section lists the hardware configuration of a standard modem with a fixed rate filter
installed.
Hardware Requirements
Description
Modem Chassis
X = 1 — SDM-650B Chassis
AS/0356 Rev. F or higher
Monitor and Control
M&C Software Requirements
SDM-650B Ver. 2.66 or higher
AS/0773-X Modulator
X = 1 — SDM-650B
X = 3 — SDM-650F
AS/0715-X Modulator Daughter
X = 1 — Fixed Rate Closed Network
AS/0778-X Demodulator
X = 1 — SDM-70/140 MHz 75Ω
X = 6 — SDM-70/140 MHz 50Ω
AS/0362-X Demodulator Daughter
X = 1 — Single Rate Filter Closed Network
X = 2 — Two Rate Filter Closed Network
X = 3 — Three Rate Filter Closed Network
X = 4 — Four Rate Filter Closed Network
AS/0365-X Sequential Decoder Option
X = 1 — Sequential Decoder with Rail
Assembly #
AS/1099-X REV-
Rev. 6
A–5
Data Rates and Filters
SDM-650B Satellite Modem
A.2 Variable Rate Filters
A.2.1 Data Rate Change Instructions
1. Turn OFF modem power switch.
2. Remove the modulator card (AS/0773) using the black card ejectors. Verify the
daughter card is a variable rate filter (AS/0930). If not, refer to Section A.1.
3. Re-install the modulator card into the modem chassis.
4. Remove the demodulator card (AS/0778) using white card ejectors. Verify the
daughter card is a variable rate filter (AS/0929). Re-install the demodulator card
into the modem chassis.
5. Remove the M&C board and JP6 (battery ON/OFF). Short the leads of capacitor
C12. Replace the battery jumper to the ON position, and re-insert the M&C card
into the modem.
6. Turn ON the power switch.
7. Go to the Utility menu on the front panel, and program the time, day, TXA, TXB,
TXC, TXD, RXA, RXB, RXC, and RXD to the new data/code rates.
8. Go to the Config menu on the front panel, and select either the desired TX and
RX rate, or TXV and RXV. Enter the desired data/code rates into the menu and
press [ENTER]. Only data rates up to and including 2048 kbit/s with a variable
rate filter can be selected. Refer to Table 6-2 for a list of the programmable data
rates of the variable rate filters. Enter the Config menu, and turn ON the RF
output.
The software change is complete.
A–6
Rev. 6
SDM-650B Satellite Modem
Data Rates and Filters
A.2.2 Hardware Configuration
This section lists the differences between a standard modem and a modem with the
variable rate filter installed.
A variable rate modem is end-to-end compatible with a non-variable rate modem of the
same model number. In most cases, the modem can be used as a prime or backup modem
in the same protection switch with a non-variable rate modem. In order for the existing
switch to operate with a variable rate modem, a software upgrade to the switch and
non-variable rate modems may be required. Contact the EFData Customer Support
Department for any questions regarding this matter.
Assembly #
AS/1099-X Rev. AS/0356 Rev. F
or higher
AS/0773-X AS/0929-X AS/0778-X AS/0930-X AS/0365-X -
Rev. 6
Hardware Requirements
Description
Modem Chassis
X = 1 — SDM-650B Chassis
Monitor and Control
M&C Software Requirements
SDM-650B Ver. 2.66 or higher
Modulator
X = 1 — SDM-650B
X = 3 — SDM-650F
Modulator Daughter
X = 1 — Variable Rate Closed Network EFData Filtering
X = 3 — Variable Rate Closed Network Fairchild Compatible
Demodulator
X = 1 — SDM-70/140 MHz 75Ω
X = 6 — SDM-70/140 MHz 50Ω
Demodulator Daughter
X = 1 — Variable Rate Closed Network
Sequential Decoder Option
X = 1 — Sequential Decoder with Rail
A–7
Data Rates and Filters
SDM-650B Satellite Modem
The following functions are found in the Select Config menu. Refer to Chapter 4 for
more information.
TXR
Transmitter Rate.
On entry, the current transmitter rate is displayed with the flashing cursor on the first
character of the coding type on line 1, and the data rate on line 2. Use the arrow keys
to select one of four pre-defined rates or variable. Press [ENTER] when TXV is
displayed to change the rate using the variable rate selection. A flashing cursor will be
displayed on the first character of the coding type on line 1. Use [←] and [→] to move
the flashing cursor. Use [↑] and [↓] to increment or decrement the digit at the flashing
cursor. Press [ENTER] to execute the change.
RXR
Note: When the TX rate has been programmed, the transmitter is automatically
turned OFF to prevent swamping of other channels. Use the RF_Out function to turn
ON the transmitter.
Receiver Rate.
On entry, the current receiver rate is displayed with the flashing cursor on the first
character of the coding type on line 1, and the data rate on line 2. Use the arrow keys
to select one of four pre-defined rates or variable. Press [ENTER] when RXV is
displayed to change the rate using the variable rate selection. A flashing cursor will be
displayed on the first character of the coding type on line 1. Use [←] and [→] to move
the flashing cursor. Use [↑] and [↓] to increment or decrement the digit at the flashing
cursor. Press [ENTER] to execute the change.
A–8
Rev. 6
SDM-650B Satellite Modem
Data Rates and Filters
A.2.3 Utility
The following functions are found in the Utility menu. Refer to Chapter 4 for the
functions not mentioned below.
FILTERS ADJUST
Variable Rate Filters K Factor Settings.
These are factory set parameters. The operator is not allowed to
view or change these parameters without authorization from an
EFData Customer Support Department representative.
CAUTION
ASSIGN TX_FLTRS
Do not try to enter this mode. An incorrect parameter change
will result in unit failure.
Modulator Symbol Rate Assignment.
The modulator has four symbol rate filter assignments. Each filter is
for a specific symbol rate. The data rate and coder rate for each filter
is established upon initial modulator installation and when
circumstances indicate the need to do so. Filters are designated as
A, B, C, and D. To view the current filter assignments, press
[ENTER] when the ASSIGN TX_FLTRS selection is displayed from
the Utility menu. On line 1 of the display will be TXA, which indicates
transmitter filter A. Following TXA on line 1 will be the code rate (1/2,
3/4, or 7/8). On line 2 will be the data rate assigned to filter A. Use
[←] and [→] to see the assignments for filters B, C, and D (TXB, TXC,
and TXD). To change a filter assignment, press [ENTER] when the
data for that filter is displayed. Use [←] and [→] until the flashing
cursor is at the parameter to be changed. Then use [↑] and [↓] to
change that parameter. When all changes are made, press [ENTER]
to confirm the assignment.
Note: These assignments are used for the selection of TXR in the
Config menu.
Rev. 6
A–9
Data Rates and Filters
SDM-650B Satellite Modem
ASSIGN RX_FLTRS
Demodulator Symbol Rate Assignment.
The demodulator has four symbol rate filter assignments. Each filter
is for a specific symbol rate. The data rate and coder rate for each
filter is established upon initial modulator installation and when
circumstances indicate the need to do so. Filters are designated as
A, B, C, and D. To view the current filter assignments, press
[ENTER] when the ASSIGN RX-FLTRS selection is displayed from
the Utility Functions menu. On line 1 of the display will be RXA, which
indicates receive filter A. Following RXA on line 1 will be the code
rate (1/2, 3/4, or 7/8). On line 2 will be the data rate assigned to filter
A. Use [←] and [→] to see the assignments for filters B, C, and D
(RXB, RXC, and RXD). To change a filter assignment, press
[ENTER] when the data for that filter is displayed. Use [←] and [→]
until the flashing cursor is at the parameter to be changed. Then use
[↑] and [↓] to change that parameter. When all changes are made,
press [ENTER] to confirm the assignment.
Note: These assignments are used for the selection of RXR in the
Config menu.
A–10
Rev. 6
Appendix B.
REMOTE CONTROL OPERATION
This appendix describes the remote control operation of the SDM-650B:
•
Section B.1 describes the standard version.
•
Section B.2 describes the modem with the asynchronous overhead channel unit
option installed.
Note: For remote control operation information on the modem with the Trojan interface
option installed, refer to Appendix G.
B.1 Standard Version
This section describes the remote control operation of the standard SDM-650B:
•
•
Rev. 6
Firmware number:
Software version:
FW/0713-35R
4.16
B–1
Remote Control Operation
SDM-650B Satellite Modem
B.1.1 General
Remote controls and status information are transferred via an RS-485 (optional RS-232-C)
serial communications link.
Commands and data are transferred on the remote control communications link as
US ASCII-encoded character strings.
The remote communications link is operated in a half-duplex mode.
Communications on the remote link are initiated by a remote controller or terminal. The
modem never transmits data on the link unless it is commanded to do so.
B.1.2 Message Structure
The ASCII character format used requires 11 bits/character:
•
•
•
•
1 start bit
7 information bits
1 parity bit (odd/even)
2 stop bits
Messages on the remote link fall into the categories of commands and responses.
Commands are messages which are transmitted to a satellite modem, while responses are
messages returned by a satellite modem in response to a command.
The general message structure is as follows:
•
•
•
•
Start Character
Device Address
Command/Response
End of Message Character
B.1.2.1 Start Character
A single character precedes all messages transmitted on the remote link. This character flags
the start of a message. This character is:
•
•
B–2
“<” for commands
“>” for responses
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.2.2 Device Address
The device address is the address of the one satellite modem which is designated to receive
a transmitted command, or which is responding to a command.
Valid device addresses are 1 to 3 characters long, and in the range of 1 to 255. Address 0 is
reserved as a global address which simultaneously addresses all devices on a given
communications link. Devices do not acknowledge global commands.
Each satellite modem which is connected to a common remote communications link must
be assigned its own unique address. Addresses are software selectable at the modem, and
must be in the range of 1 to 255.
Rev. 6
B–3
Remote Control Operation
SDM-650B Satellite Modem
B.1.2.3 Command/Response
The command/response portion of the message contains a variable length character
sequence which conveys command and response data.
If a satellite modem receives a message addressed to it which does not match the established
protocol or cannot be implemented, a negative acknowledgment message is sent in
response. This message is:
•
>add/?ER1_PARITY ERROR”cr””lf”]
(Error message for received parity errors.)
•
>add/?ER2_INVALID PARAMETER”cr””lf”]
(Error message for a recognized command which cannot be implemented or has parameters
which are out of range.)
•
>add/?ER3_UNRECOGNIZABLE COMMAND”cr””lf”]
(Error message for unrecognizable command or bad command syntax.)
•
>add/?ER4_MODEM IN LOCAL MODE”cr””lf”]
(Modem in local error; use the REM command to go to remote mode.)
•
>add/?ER5_HARD CODED PARAMETER”cr””lf”]
(Error message indicating that the parameter is hardware dependent and may not be changed
remotely.)
Note: “add” is used to indicate a valid 1 to 3 character device address in the range
between 1 and 255.
B.1.2.4 End Character
Each message is ended with a single character which signals the end of the message:
•
•
B–4
“cr”
“]”
Carriage return character for commands
End bracket for responses
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.3 Configuration Commands/Responses
B.1.3.1 Remote
This command configures the modem for remote operation. The modem will respond to
any status request at any time. However, the modem must be in “Remote Mode” to
change configuration parameters.
Command:
Response:
<add/REM_”cr”
>add/REM_”cr””lf”]
B.1.3.2 Set Modulator Frequency
Command:
Response:
<add/MF_nnn.nnnn”cr”
>add/MF_nnn.nnnn”cr”
RF_OFF”cr””lf”]
Status Only:
Response:
<add/MF_”cr”
>add/MF_nnn.nnnn”cr””lf”]
Where: nnn.nnnn = 50.0000 to 90.0000, and 100.0000 to 180.0000 for the 140 MHz
modulator.
Note: When modulator frequency is changed, the RF output is switched OFF.
B.1.3.3 Set RF Output
Command:
Response:
<add/RF_xxx”cr”
>add/RF_xxx”cr””lf”]
Status Only:
Response:
<add/RF_”cr”
>add/RF_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.1.3.4 Set Demodulator Frequency
Command:
Response:
<add/DF_nnn.nnnn”cr”
>add/DF_nnn.nnnn”cr””lf”]
Status Only:
Response:
<add/DF_”cr”
>add/DF_nnn.nnnn”cr””lf”]
Where: nnn.nnnn = 50.0000 to 90.0000, and 100.0000 to 180.0000 for the 140 MHz
modulator.
Rev. 6
B–5
Remote Control Operation
SDM-650B Satellite Modem
B.1.3.5 Set Modulator Power Offset
Command:
Response:
<add/MPO_snn.n”cr”
>add/MPO_snn.n”cr””lf”]
Status Only:
Response:
<add/MPO_”cr”
>add/MPO_snn.n”cr””lf”]
Where: snn.n = +20.0 to -20.0, in 0.5 dB increments.
Notes:
1. This will be the highest modulator power that will be displayed and programmed.
2. Use the MOP_ command to actually change the modulator output power.
B.1.3.6 Set Modulator Output Power Level
Command:
Response:
<add/MOP_snn.n”cr”
>add/MOP_snn.n”cr””lf”]
Status Only:
Response:
<add/MOP_”cr”
>add/MOP_snn.n”cr””lf”]
Where:
snn.n = +20.0 to -45.0, in 0.5 dB increments for 140 MHz modulators.
snn.n = +20.0 to -30.0, in 0.5 dB increments for 70 MHz modulators.
Notes:
1. Power levels may be programmed for a maximum value specified by the
modulator power offset with a range of 25 dB and 10 dB below the maximum
value for the 140 MHz modulator and the 70 MHz modulator, respectively.
2. See the MPO_ command specification for more information.
B–6
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.3.7 Modulator Rate
The modulator has four symbol rate filters. Each filter is for a specific symbol rate. The
data rate and coder rate for each filter must be established upon initial modulator
installation, and when circumstances indicate the need to do so.
Filters are designated as A, B, C, and D. If a filter is not physically present in the system,
it may be assigned “N/A” (not assigned).
Additionally, filters which are factory programmed may not be remotely programmed,
and will return the “error 5” message when a programming command is issued.
Notes: For the variable rate modulator option:
1. Modulators with the variable rate option installed may have four preprogrammed
rates available by using the filter rate assignment commands. These rates are
selected using the standard “SMRx_” commands.
2. Modems that have the variable rate option installed will also respond to the
special “SMRV_” command.
B.1.3.7.1 Modulator Filter Rate Assignment
Command:
Response:
<add/AMRx_nnn_mmmm.m”cr”
>add/AMRx_nnn_mmmm.m”cr””lf”]
Status Only:
Response:
<add/AMRx_”cr”
>add/AMRx_nnn_mmmm.m”cr””lf”]
Where:
x = A, B, C, or D (Filter designator).
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
Example:
Command:
Response:
Rev. 6
<add/AMRx_N/A”cr”
>add/AMRx_N/A”cr””lf”]
B–7
Remote Control Operation
SDM-650B Satellite Modem
B.1.3.7.2 Select Modulator Rate
Command:
Response:
<add/SMRx_”cr”
>add/SMRx_”cr”
RF_OFF”cr””lf”]
Status Only:
(See MR command.)
Where: x = A, B, C, or D (Filter designator).
Notes:
1. Setting the modulator turns OFF the RF transmitter.
2. If the modem is commanded to a filter (rate) which is not assigned (N/A), the
“error 2” message will be returned.
B.1.3.7.3 Select Modulator Rate Variable
Note: This command is only applicable for the variable rate option.
Command:
Response:
<add/SMRV_nnn_mmmm.m”cr”
>add/SMRV_nnn_mmmm.m”cr””lf”]
RF_OFF”cr””lf”]
Status Only:
(See MR command.)
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: Setting the modulator turns OFF the RF transmitter.
B–8
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.3.8 Demodulator Rate
The demodulator has four symbol rate filters. Each filter is for a specific symbol rate. The
data rate and decoder rate for each filter must be established upon initial demodulator
installation, and when circumstances indicate the need to do so.
Filters are designated as A, B, C, and D. If a filter is not physically present in the system,
it may be assigned “N/A” (not assigned).
Additionally, filters which are factory programmed may not be remotely programmed,
and will return the “error 5” message when a programming command is issued.
Notes: For variable rate demodulator option:
1. Demodulators with the variable rate option installed may have four
preprogrammed rates available by using the filter rate assignment commands.
These rates are selected using the standard “SDRx_” commands.
2. Modems that have the variable rate option installed will also respond to the
special “SDRV_” command. This allows for truly variable rate control, while
maintaining compatibility with previous systems.
B.1.3.8.1 Demodulator Filter Rate Assignment
Command:
Response:
<add/ADRx_nnn_mmmm.m”cr”
>add/ADRx_nnn_mmmm.m”cr””lf”]
Status Only:
Response:
<add/ADRx_”cr”
>add/ADRx_nnn_mmmm.m”cr””lf”]
Where:
x = A, B, C, or D (Filter designator).
nnn = 1/2, 3/4, 7/8, or BP12 (Decoder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
Example:
Command:
Response:
Rev. 6
<add/ADRx_N/A”cr”
>add/ADRx_N/A”cr””lf”]
B–9
Remote Control Operation
SDM-650B Satellite Modem
B.1.3.8.2 Select Demodulator Rate
Command:
Response:
<add/SDRx_”cr”
>add/SDRx_”cr””lf”]
Status Only:
(See DR command.)
Where: x = A, B, C, or D (Filter designator).
Note: If the modem is commanded to a filter (rate) which is not assigned (N/A), the
“error 2” message will be returned.
B.1.3.8.3 Select Demodulator Rate Variable
Note: This command is only applicable for the variable rate option.
Command:
Response:
<add/SDRV_nnn_mmmm.m”cr”
>add/SDRV_nnn_mmmm.m”cr””lf”]
Status Only:
(See DR command.)
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
B.1.3.9 Scrambler Enable
Command:
Response:
<add/SE_xxx”cr”
>add/SE_xxx”cr””lf”]
Status Only:
Response:
<add/SE_”cr”
>add/SE_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.1.3.10 Descrambler Enable
Command:
Response:
<add/DE_xxx”cr”
>add/DE_xxx”cr””lf”]
Status Only:
Response:
<add/DE_”cr”
>add/DE_xxx”cr””lf”]
Where: xxx = ON or OFF.
B–10
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.3.11 Differential Encoder Enable
Command:
Response:
<add/DENC_xxx”cr”
>add/DENC_xxx”cr”lf”]
Status Only:
Response:
<add/DENC_”cr”
>add/DENC_xxx”cr”lf”]
Where: xxx = ON or OFF.
B.1.3.12 Transmit Clock
Command:
Response:
<add/TC_xxx”cr”
>add/TC_xxx”cr””lf”]
Status Only:
Response:
<add/TC_”cr”
>add/TC_xxx”cr””lf”]
Where: xxx = INT or EXT.
B.1.3.13 Receive Clock
Command:
Response:
<add/RC_xxx”cr”
>add/RC_xxx”cr””lf”]
Status Only:
Response:
<add/RC_”cr”
>add/RC_xxx”cr””lf”]
Where: xxx = NRM or INV.
B.1.3.14 Baseband Loopback
Command:
Response:
<add/BBL_xxx”cr”
>add/BBL_xxx”cr””lf”]
Status Only:
Response:
<add/BBL_”cr”
>add/BBL_xxx”cr””lf”]
Where: xxx = ON or OFF.
Rev. 6
B–11
Remote Control Operation
SDM-650B Satellite Modem
B.1.3.15 RF Loopback
Command:
Response:
<add/RFL_xxx”cr”
>add/RFL_xxx”cr””lf”]
Status Only:
Response:
<add/RFL_”cr”
>add/RFL_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.1.3.16 IF Loopback
Command:
Response:
<add/IFL_xxx”cr”
>add/IFL_xxx”cr””lf”]
Status Only:
Response:
<add/IFL_”cr”
>add/IFL_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.1.3.17 Time of Day
Command:
Response:
<add/TIME_hh:mmxx”cr”
>add/TIME_hh:mmxx”cr””lf”]
Status Only:
Response:
<add/TIME_”cr”
>add/TIME_hh:mmxx”cr””lf”]
Where:
hh = hours.
mm = minutes.
xx = AM or PM.
Example: Set modem 67 time to 10:45 PM.
Command:
Response:
B–12
<67/TIME_10:45PM”cr”
>67/TIME_10:45PM”cr””lf”]
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.3.18 Date
Command:
Response:
<add/DATE_mm/dd/yy”cr”
>add/DATE_mm/dd/yy”cr””lf”]
Status Only:
Response:
<add/DATE_”cr”
>add/DATE_mm/dd/yy”cr””lf”]
Where:
mm = month.
dd = day.
yy = year.
Example: Set modem 235 date to 11/30/87.
Command:
Response:
<235/DATE_11/30/87”cr”
>235/DATE_11/30/87”cr””lf”]
B.1.3.19 Clear Stored Faults
This command is used to clear all stored faults logged by the modem.
Command:
Response:
<add/CLSF_”cr”
>add/CLSF_”cr””lf”]
B.1.3.20 BER Threshold
Command:
Response:
<add/BERT_xxxx”cr”
>add/BERT_xxxx”cr””lf”]
Status Only:
Response:
<add/BERT_”cr”
>add/BERT_xxxx”cr””lf”]
Where: xxxx = NONE or 1E-n (n = 3, 4, 5, 6, 7, or 8 [exponent of threshold]).
Rev. 6
B–13
Remote Control Operation
SDM-650B Satellite Modem
B.1.3.21 Sweep Reacquisition
This command is used to specify time duration of the reacquisition mode. The sweep is
reduced to ± 2500 Hz of the last known lock point. Use of this function may reduce
reacquisition times at low data rates. To inhibit the sweep reacquisition mode, set
“SR” to 0 seconds.
Command:
Response:
<add/SR_xxx”cr”
>add/SR_xxx”cr””lf”]
Status Only:
Response:
<add/SR_”cr”
>add/SR_xxx”cr””lf”]
Where: xxx = 0 to 999 (number of seconds).
B.1.3.22 Fast Acquisition Mode
This command is used to enable or disable fast acquisition and directed sweep modes of
operation.
When fast acquisition is enabled, the fast acquisition algorithm (which requires hardware
calibration) is used for acquisition of receive symbol rates of 128 kbit/s or lower.
However, if the sweep range is set to less than 50 kHz, acquisition will be dictated by the
directed sweep specifications, and the fast acquisition algorithm will not be used.
The directed sweep functions are also available when fast acquisition is enabled. Directed
sweep provides three commands for manipulating the acquisition process. These
commands are:
•
•
•
SCF_ (Sweep Center Frequency)
SWR_ (Sweep Range)
SD_ (Sweep Direction)
Note: These commands will be discussed in later sections.
Command:
Response:
<add/FAM_xxx”cr”
>add/FAM_xxx”cr””lf”]
Status Only:
Response:
<add/FAM_”cr”
>add/FAM_xxx”cr””lf”]
Where: xxx = ON or OFF (OFF disables fast acquisition and directed sweep modes).
B–14
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.3.22.1 Sweep Center Frequency
This command sets the sweep center frequency. During carrier acquisition, the sweep
starts at an offset, which is one-half the currently programmed sweep range (SWR_) from
the sweep center frequency. The direction of the offset is determined by the currently
programmed sweep direction (SD_).
The sweep center frequency may be set in the range of +25000 to -25000 Hz.
Command:
Response:
<add/SCF_xnnnnn”cr””lf”]
>add/SCF_xnnnnn”cr””lf”]
Status Only:
Response:
<add/SCF_”cr””lf”]
>add/SCF_xnnnnn”cr””lf”]
Where:
x = + or - (sweep offset direction).
nnnnn = 0 to 25000.
Note: This command is only valid when fast acquisition is enabled. See the “FAM_”
command definition.
B.1.3.22.2 Sweep Width Range
This command sets the overall travel of the sweep during acquisition. The sweep width
may be set in the range of 0 Hz to 50000 Hz.
Command:
Response:
<add/SWR_nnnnn”cr””lf”]
>add/SWR_nnnnn”cr””lf”]
Status Only:
Response:
<add/SWR_”cr””lf”]
>add/SWR_nnnnn”cr””lf”]
Where: nnnnn = 0 to 50000.
Note: This command is only valid when fast acquisition is enabled. See the “FAM_”
command definition.
Rev. 6
B–15
Remote Control Operation
SDM-650B Satellite Modem
B.1.3.22.3 Sweep Direction
This command sets the direction of the sweep travel. “+” sets incremental sweep, while
“-” sets decremental sweep.
Command:
Response:
<add/SD_s”cr””lf”]
>add/SD_s”cr””lf”]
Status Only:
Response:
<add/SD_”cr””lf”]
>add/SD_s”cr””lf”]
Where: s = + or - (direction of sweep travel during acquisition).
Note: This command is only valid when fast acquisition is enabled. See the “FAM_”
command definition.
B.1.3.23 Modem Operation Mode
This command configures the modem for simplex or duplex operation modes. When
transmit-only mode is selected, receive faults are inhibited. When receive-only mode is
selected, transmit faults are inhibited.
Command:
Response:
<add/MOM_xxxxxxx”cr”
>add/MOM_xxxxxxx”cr””lf”]
Status Only:
Response:
<add/MOM_”cr”
>add/MOM_xxxxxxx”cr””lf”]
Where: xxxxxxx = TX_ONLY, RX_ONLY, or DUPLEX.
B.1.3.24 Buffer Control Mode
This command is used to enable or disable M&C buffer control.
Command:
Response:
<add/BUFF_xxx”cr”
>add/BUFF_xxx”cr””lf”]
Status Only:
Response:
<add/BUFF_”cr”
>add/BUFF_xxx”cr””lf”]
Where: xxx = ON or OFF (OFF disables Buffer Clock, Buffer Center, and Buffer Size).
Note: For optional Doppler buffer only.
B–16
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.3.24.1 Buffer Clock
Command:
Response:
<add/BC_xxx”cr”
>add/BC_xxx”cr””lf”]
Status Only:
Response:
<add/BC_”cr”
>add/BC_xxx”cr””lf”]
Where: xxx = TXC, RXC, or EXT.
Note: This command is only valid when Buffer Control is enabled. See the “BUFF_”
command definition.
B.1.3.24.2 Interface Buffer Center
This command centers the Doppler buffer.
Command:
Response:
<add/IBC_”cr”
>add/IBC_”cr””lf”]
Note: This command is only valid when Buffer Control is enabled. See the “BUFF_”
command definition.
B.1.3.24.3 Interface Buffer Size
This command sets the Doppler buffer depth in bits.
Command:
Response:
<add/IBS_nnnnn”cr”
>add/IBS_nnnnn”cr””lf”]
Status Only:
Response:
<add/IBS_”cr”
>add/IBS_nnnnn”cr””lf”]
Notes:
1. Valid buffer depths are 512, 1024, 2048, 4096, 8192, 16384, and 32768.
2. This command is only valid when Buffer Control is enabled. See the “BUFF_”
command definition.
Rev. 6
B–17
Remote Control Operation
SDM-650B Satellite Modem
B.1.4. Status Commands/Responses
B.1.4.1 Configuration
B.1.4.1.1 Modulator/Coder Status
The Modulator/Coder configuration status command causes a block of data to be returned
by the addressed modem. The block of data reflects the current configuration status of the
Modulator/Coder.
Command:
Response:
<add/MCS_”cr”
>add/MCS_”cr”
RF_xxx”cr”
MF_nnn.nnnn”cr”
MPO_snn.n”cr”
MOP_snn.n”cr”
MR_nnn_mmmm.m”cr”
AMRA_nnn_mmmm.m”cr”
AMRB_nnn_mmmm.m”cr”
AMRC_nnn_mmmm.m”cr”
AMRD_nnn_mmmm.m”cr”
SE_xxx”cr”
COM_xxx”cr”
DENC_xxx”cr”
TC_xxx”cr”
AMRV_nnn.mmmm.m”cr””lf”]
RF Output (ON/OFF)
Modulator Frequency
Modulator Power Offset
Modulator Output Power
Modulator Rate
Filter “A” Assignment
Filter “B” Assignment
Filter “C” Assignment
Filter “D” Assignment
Scrambler Enable (ON/OFF)
Carrier Only Mode (ON/OFF)
Differential Encoder (ON/OFF)
Transmit Clock (INT/EXT)
Modulator Variable Rate Assignment
(Variable Rate Option Only)
B.1.4.1.2 Modulator/Coder Program
This command is used by the SMS-658 M:N protection switch to collect information that
is necessary to configure backup modems.
Command:
Response:
B–18
<add/MCP_”cr”
>add/MCP_”cr”
MF_nnn.nnnn”cr”
MPO_snn.n”cr”
MOP_snn.n”cr”
MR_nnn_mmmm.m”cr”
SE_xxx”cr”
DENC_xxx”cr”
TC_xxx”cr”
RF_xxx”cr””lf”]
Modulator Frequency
Modulator Power Offset
Modulator Output Power
Modulator Rate
Scrambler Enable (ON/OFF)
Differential Encoder (ON/OFF)
Transmit Clock (INT/EXT)
RF Output (ON/OFF)
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.4.1.3 Demodulator/Decoder Configuration Status
The Demodulator/Decoder configuration status command causes a block of data to be
returned by the addressed modem. The block of data reflects the current configuration of
the demod.
Command:
Response:
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 2)
(See Note 2)
<add/DCS_”cr”
>add/DCS_”cr”
DF_nnn.nnnn”cr”
DR_nnn_mmmm.m”cr”
ADRA_nnn_mmmm.m”cr”
ADRB_nnn_mmmm.m”cr”
ADRC_nnn_mmmm.m”cr”
ADRD_nnn_mmmm.m”cr”
DE_xxx”cr”
RC_xxx”cr”
BBL_xxx”cr”
RFL_xxx”cr”
BERT_xxxx”cr”
SR_xxx”cr”
IFL_xxx”cr”
SCF_snnnnn”cr”
SWR_nnnnn”cr”
SD_s”cr”
FAM_xxx”cr”
BC_xxx”cr”
IBS_nnnnn”cr”
ADRV_nnn.mmmm.m”cr””lf”]
Demodulator Frequency
Demodulator Data Rate
Filter “A” Assignment
Filter “B” Assignment
Filter “C” Assignment
Filter “D” Assignment
Descrambler Enable (ON/OFF)
Receive Clock (NRM/INV)
Baseband Loopback (ON/OFF)
RF Loopback (ON/OFF)
BER Threshold
Sweep Reacquisition (seconds)
IF Loopback (ON/OFF)
Sweep Center Frequency
Sweep Width
Sweep Direction
Fast Acquisition Mode
Buffer Clock Source
Interface Buffer Size
Demodulator Variable Rate Assignment
(Variable Rate Option Only)
Notes:
1. “SCF_”, “SWR_”, and “SD_” responses are returned only when fast acquisition
is enabled. See the “FAM_” command definition.
2. “BC_” and “IBS_” responses are returned only when Buffer Control is enabled.
See the “BUFF_” command definition.
Rev. 6
B–19
Remote Control Operation
SDM-650B Satellite Modem
B.1.4.1.4 Demodulator/Decoder Configuration Program
This command is used by the SMS-658 M:N protection switch to collect information that
is necessary to configure backup modems.
Command:
Response:
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 2)
(See Note 2)
<add/DCP_”cr”
>add/DCP_”cr”
BBL_xxx”cr”
IFL_xxx”cr”
RFL_xxx”cr”
DF_nnn.nnnn”cr”
DR_nnn_mmmm.m”cr”
DE_xxx”cr”
RC_xxx”cr”
BERT_xxxx”cr”
SR_xxx”cr”
FAM_xxx”cr”
SCF_snnnnn”cr”
SWR_nnnnn”cr”
SD_s”cr”
BC_xxx”cr”
IBS_nnnnn”cr””lf”]
Baseband Loopback (ON/OFF)
IF Loopback (ON/OFF)
RF Loopback (ON/OFF)
Demodulator Frequency
Demodulator Data Rate
Descrambler Enable (ON/OFF)
Receive Clock (NRM/INV)
BER Threshold
Sweep Reacquisition (seconds)
Fast Acquisition Mode
Sweep Center Frequency
Sweep Width
Sweep Direction
Buffer Clock Source
Interface Buffer Size
Notes:
1. “SCF_”, “SWR_”, and “SD_” responses are returned only when fast acquisition
is enabled. See the “FAM_” command definition.
2. “BC_” and “IBS_” responses are returned only when Buffer Control is enabled.
See the “BUFF_” command definition.
B.1.4.2 Modem Faults Status (Summary)
This command returns the current overall fault conditions of the modem.
Command:
Response:
(See Note)
<add/MFS_”cr”
>add/MFS_”cr”
DMD_xxx”cr”
MOD_xxx”cr”
CEQ_xxx”cr”
IRX_xxx”cr””lf”]
Demodulator (FLT/OK)
Modulator (FLT/OK)
Common Equipment (FLT/OK)
Interface Receive Side (FLT/OK)
Note: “IRX_” response is returned only when Buffer Control is enabled. See the
“BUFF_” command definition.
B–20
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.4.3 Modulator Status
The modulator status is returned as a block of data which indicates general status
information.
Command:
Response:
<add/MS_”cr”
>add/MS_”cr”
RF_xxx”cr”
MOD_xxx”cr”
AGC_xxx”cr”
SYN_xxx”cr”
BCLK_xxx”cr”
TCLK_xxx”cr”
ICH_xxx”cr”
QCH_xxx”cr”
SFLT_xx”cr””lf”]
RF Output (ON/OFF) actual status, not
configured
Module missing or will not program (OK/FLT)
AGC Leveled (OK/FLT)
Carrier Synthesizer (OK/FLT)
Bit Clock (OK/FLT)
Transmit Clock (OK/FLT)
I Channel (OK/FLT)
Q Channel (OK/FLT)
Number of Stored Faults Logged (0 to 10)
B.1.4.4 Demodulator Status
The demodulator status is returned as a block of data which provides general status
information.
Command:
Response:
Rev. 6
<add/DS_”cr”
>add/DS_”cr”
DMD_xxx”cr”
CD_xxx”cr”
SYN_xxx”cr”
DSCR_xxx”cr”
ICH_xxx”cr”
QCH_xxx”cr”
BCLK_xxx”cr”
BERT_xxx”cr”
RSL_-nn.ndBm”cr”
CSV_snnnnn”cr”
SFLT_xx”cr””lf”]
Demod Module (OK/FLT)
Carrier Detect (OK/FLT)
Synthesizer Lock (OK/FLT)
Descrambler (OK/FLT)
I Channel (OK/FLT)
Q Channel (OK/FLT)
Bit Clock (OK/FLT)
BER Threshold (OK/FLT)
Receive Signal Level (level or no data)
Current Sweep Value
Number of Stored Faults Logged (0 to 10)
B–21
Remote Control Operation
SDM-650B Satellite Modem
B.1.4.5 Common Equipment Status
The common equipment status command causes a block of data to be returned, which
indicates the status of the common equipment.
Command:
Response:
<add/CES_”cr”
>add/CES_”cr”
M&C_xxx”cr”
INT_xxx”cr”
TXC_xxx”cr”
BAT_xxx”cr”
PS1_xxx”cr”
PS2_xxx”cr”
PS3_xxx”cr”
MODE_xxxxxx”cr”
SW_x.xxx”cr”
SFLT_xx”cr””lf”]
Monitor and Control Module (OK/FLT)
Data Interface Module (OK/FLT)
Transmit Clock Loss (DS-1 only)
Battery (OK/FLT)
+5V Power Supply (OK/FLT)
+12V Power Supply (OK/FLT)
-12V Power Supply (OK/FLT)
Mode (LOCAL or REMOTE)
Software Version
Number of Stored Faults Logged (0 to 10)
B.1.4.6 Interface Receive Side Status
Command:
Response:
<add/IRXS_”cr”
>add/IRXS_”cr”
OVFL_xxx”cr”
UNFL_xxx”cr”
SFLT_xx”cr””lf”]
Buffer Overflow (OK/FLT)
Buffer Underflow (OK/FLT)
Number of Stored Faults Logged (0 to 10)
Note: This command is only valid when Buffer Control is enabled. See the “BUFF_”
command definition.
B–22
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.4.7 BER Status
B.1.4.7.1 Raw BER
Command:
Response:
<add/RBER_”cr”
>add/RBER_nnnnE-4”cr””lf”]
Where: nnnn = RBER or < 1.0 (lower limit).
Example: Request raw BER from modem 123.
Command:
Response:
<123/RBER_”cr”
>123/RBER_152E-4”cr””lf”]
Where: RBER = .0152 errors/bit.
Note: “No Data” is returned if no carrier is detected (decoder not locked).
B.1.4.7.2 Corrected BER
Command:
Response:
<add/CBER_”cr”
>add/CBER_nE-m”cr””lf”]
Example: Request corrected BER from modem 19.
Command:
Response:
<19/CBER_”cr”
>19/CBER_2E-5”cr””lf”]
Where: CBER = .00002 errors/bit.
Notes:
1. Corrected BER limits are lower < 1E-8, upper > 1E-3.
2. “No Data” is returned if no carrier is detected (decoder not locked).
Rev. 6
B–23
Remote Control Operation
SDM-650B Satellite Modem
B.1.4.8 Eb/N0 Status
The Eb/N0 status command causes the Eb/N0 ratio to be returned. Eb/N0 is returned in dB.
Command:
Response:
<add/EBN0_”cr”
>add/EBN0_n.ndB”cr””lf”]
Example: Request Eb/N0 ratio from modem 2.
Command:
Response:
<2/EBN0_”cr”
>2/EBN0_6.2dB”cr””lf”]
Where: Eb/N0 = 6.2 dB.
Notes:
1. Eb/N0 limits are lower < 3 2 dB, upper > 9.7 dB.
2. “No Data” is returned if no carrier is detected (decoder not locked).
B.1.4.9 Modulator Rate Status
Command:
Response:
<add/MR_”cr”
>add/MR_nnn_mmmm.m”cr””lf”]
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
B.1.4.10 Demodulator Rate Status
Command:
Response:
<add/DR_”cr”
>add/DR_nnn_mmmm.m”cr””lf”]
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
B–24
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.4.11 Receive Signal Level Status
Command:
Response:
<add/RSL_”cr”
>add/RSL_-nn.ndBm”cr””lf”]
B.1.4.12 Current Sweep Value
This command returns the current sweep value and the decoder lock status.
Command:
Response:
<add/CSV_”cr””lf”]
>add/CSV_snnnnn”cr”
CD_xxx”cr””lf”]
Where:
s = + or - (sweep offset direction).
nnnnn = 0 to 25000.
xxx = OK or FLT (decoder lock status OK or FAULT).
Rev. 6
B–25
Remote Control Operation
SDM-650B Satellite Modem
B.1.4.13 Stored Faults
Information on stored faults is returned when requested. If no stored fault exists for a
given fault number, the words “NO FAULT” will be returned instead of the normal
time/date status information.
The following symbols are commonly used to define the stored faults status commands:
•
•
•
•
•
•
•
“#”
hh
mm
ss
MM
DD
YY
Fault number (0 to 9), “0” is the first fault stored.
Hours in 24-hr. format.
Minutes.
Seconds.
Month.
Day.
Year.
B.1.4.13.1 Modulator Stored Faults
Command:
Response:
<add/MSF_#”cr”
>add/MSF_# hh:mm:ss
MOD_xxx”cr”
AGC_xxx”cr”
SYN_xxx”cr”
BCLK_xxx”cr”
TCLK_xxx”cr”
ICH_xxx”cr”
QCH_xxx”cr””lf”]
MM/DD/YY”cr”
Module missing or will not program (OK/FLT)
AGC leveled (OK/FLT)
Carrier synthesizer (OK/FLT)
Bit clock (OK/FLT)
Transmit clock (OK/FLT)
I Channel (OK/FLT)
Q Channel (OK/FLT)
B.1.4.13.2 Demodulator Stored Faults
Command:
Response:
B–26
<add/DSF_#”cr”
>add/DSF_# hh:mm:ss
DMD_xxx”cr”
CD_xxx”cr”
SYN_xxx”cr”
DSCR_xxx”cr”
ICH_xxx”cr”
QCH_xxx”cr”
BCLK_xxx”cr”
BERT_xxx”cr””lf”]
MM/DD/YY”cr”
Demod Module (OK/FLT)
Carrier Detect (OK/FLT)
Synthesizer Lock (OK/FLT)
Descrambler (OK/FLT)
I Channel (OK/FLT)
Q Channel (OK/FLT)
Bit Clock (OK/FLT)
BER Threshold (OK/FLT)
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.1.4.13.3 Common Equipment Stored Faults
Command:
Response:
<add/CSF_#”cr”
>add/CSF_# hh:mm:ss
M&C_xxx”cr”
INT_xxx”cr”
TXC_xxx”cr”
BAT_xxx”cr”
PS1_xxx”cr”
PS2_xxx”cr”
PS3_xxx”cr””lf”]
MM/DD/YY”cr”
Monitor and Control Module (OK/FLT)
Data Interface Module (OK/FLT)
Transmit Clock Loss (DS1 only)
Battery (OK/FLT)
+5V Power Supply (OK/FLT)
+12V Power Supply (OK/FLT)
-12V Power Supply (OK/FLT)
B.1.4.13.4 Interface Receive Side Status Stored Faults
Command:
Response:
<add/IRSF_#”cr”
>add/IRSF_# hh:mm:ss
OVFL_xxx”cr”
UNFL_xxx”cr””lf”]
MM/DD/YY”cr”
Buffer Overflow (OK/FLT)
Buffer Underflow (OK/FLT)
Note: This command is only valid when Buffer Control is enabled. See the “BUFF_”
command definition.
Rev. 6
B–27
Remote Control Operation
SDM-650B Satellite Modem
B.1.4.14 Bulk Consolidated Status
This command causes bulk modem status to be returned. To reduce the length of the
response, message parameter data are returned without identifiers.
However, parameter identification can be determined by order of return. Each status
parameter is terminated with a “,” (comma), except for the last parameter, which has the
standard message termination sequence (”cr””lf”]).
For standardization reasons, some parameters may not be implemented, but will retain the
terminating “,” (comma). Most of the data returned is formatted the same way as the
single command status request (refer to the appropriate portions of this document in
preceding sections).
Command:
Response:
<add/BCS_”cr”
>add/BCS_p1,p2,p3, . . . pn”cr””lf”]
Where “pn” is the last parameter returned.
Parameter 1 (p1): Modulator RF output ON/OFF.
p1 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 2 (p2): Modulator IF frequency.
p2 = nnnn.nnnn, where “nnnn.nnnn” is the modulator IF frequency in MHz.
Parameter 3 (p3): Modulator output power level.
p3 = snn.n, where “snn.n” is the transmitter output power level in dBm.
Parameter 4 (p4): Modulator rate currently programmed.
p4 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 5 (p5): Modulator filter A assignment.
p5 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 6 (p6): Modulator filter B assignment.
p6 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 7 (p7): Modulator filter C assignment.
p7 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 8 (p8): Modulator filter D assignment.
p8 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 9 (p9): Scrambler enable ON/OFF.
p9 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 10 (p10): Carrier only mode ON/OFF.
p10 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 11 (p11): Differential encoder enable ON/OFF.
p11 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 12 (p12): Transmit clock source (Internal/External).
p12 = n, where “n” is “0” or “1” (“0” = INT, “1” = EXT).
Parameter 13 (p13): Demodulator IF frequency.
p13 = nnnn.nnnn, where “nnnn.nnnn” is the demodulator IF frequency in MHz.
B–28
Rev. 6
SDM-650B Satellite Modem
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 2)
(See Note 2)
Remote Control Operation
Parameter 14 (p14): Demodulator rate currently programmed.
p14 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 15 (p15): Demodulator filter A assignment.
p15 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 16 (p16): Demodulator filter B assignment.
p16 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 17 (p17): Demodulator filter C assignment.
p17 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 18 (p18): Demodulator filter D assignment.
p18 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 19 (p19): Descrambler enable ON/OFF.
p19 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 20 (p20): Receive clock (Invert/Normal).
p20 = n, where “n” is “0” or “1” (“0” = NRM, “1” = INV).
Parameter 21 (p21): Baseband loopback ON/OFF.
p21 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 22 (p22): RF loopback ON/OFF.
p22 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 23 (p23): Not implemented.
p23 = “,”.
Parameter 24 (p24): BER threshold.
p24 = nnnn, where “nnnn” is the currently programmed BER threshold in the same
format as the single command “BERT_”.
Parameter 25 (p25): Sweep Reacquisition.
p25 = nnn, where “nnn” is the reacquisition parameter in seconds.
Parameter 26 (p26): IF loopback ON/OFF.
p26 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 27 (p27): MODEM REMOTE/LOCAL mode.
p27 = n, where “n” is “0” to indicate local, or “1” to indicate remote.
Parameter 28 (p28): Sweep center programmed.
p28 = snnnnn, where “s” is “+” or “-”, and “nnnnn” is the sweep center currently
programmed.
Parameter 29 (p29): Sweep width range.
p29 = nnnnn, where “nnnnn” is in the range of 0 to 50000 Hz.
Parameter 30 (p30): Sweep direction.
p30 = n, where “n” is “+” for positive or “-” for negative sweep direction.
Parameter 31 (p31): Buffer Clock.
p31 = n, where “n” is “0” to indicate transmit, “1” to indicate receive, or “2” to indicate
external.
Parameter 32 (p32): Interface Buffer Size.
p32 = nnnnn, where “nnnnn” is the buffer size in bits.
Notes:
1. Parameters 28, 29, and 30 are only returned when fast acquisition is enabled. See
the “FAM_” command definition. Commas are always returned.
2. Parameters 31 and 32 are only returned when Buffer Control is enabled. See the
“BUFF_” command definition. Commas are always returned.
Rev. 6
B–29
Remote Control Operation
SDM-650B Satellite Modem
B.1.4.15 Bulk Consolidated Analog Status
This command is similar to the “BCS_” command, but returns modem analog parameters.
Command:
Response:
<add/BCAS_”cr”
>add/BCAS_p1,p2,p3, . . . pn”cr””lf”]
Where “pn” is the last parameter returned.
Parameter 1 (p1): Receive signal level.
p1 = -nn, where “nn” is the value of the receive signal level in dBm.
Parameter 2 (p2): Raw BER.
p2 = nnnnE-4, where “nnnn” is the raw bit errors in 10000 bits.
Parameter 3 (p3): Corrected BER.
p3 = nE-e, where “n” is the mantissa, and “e” is exponent (power of 10).
Parameter 4 (p4): Eb/N0.
p4 = n.n, where “n.n” is Eb/N0 in dB.
Note: Parameters 1 through 4 are dependent on carrier acquisition. If the decoder is not
locked, empty data blocks are returned (,,,).
B.1.4.16 Bulk Consolidated Status Faults
This command causes all modem fault status to be returned. To reduce the length of the
response, fault status is embedded into the bit structure of the characters that are returned.
Faults are indicated by a binary 1 in the designated bit position.
Command:
Response:
<add/BCSF_”cr”
>add/BCSF_abcdef”cr””lf”]
Where: Character “a”: Modulator fault status character 1.
Bit 6 = 1 always.
Bit 5 = Modulator fault.
Bit 4 = RF output status; actual, not programmed status (1 = ON, 0 = OFF).
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of modulator stored
faults.
Where: Character “b”: Modulator fault status character 2.
Bit 6 = 1 always.
Bit 5 = AGC fault.
Bit 4 = Modulator RF synthesizer fault.
Bit 3 = Bit clock fault.
Bit 2 = Transmit clock fault.
Bit 1 = I Channel fault.
Bit 0 = Q Channel fault.
B–30
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
Where: Character “c”: Demodulator fault status character 1.
Bit 6 = 1 always.
Bit 5 = Demodulator fault.
Bit 4 = Carrier detect status (0 for decoder lock).
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of demodulator
stored faults.
Where: Character “d”: Demodulator fault status character 2.
Bit 6 = 1 always.
Bit 5 = Demodulator RF synthesizer fault.
Bit 4 = Descrambler fault.
Bit 3 = I channel fault.
Bit 2 = Q channel fault.
Bit 1 = Bit clock fault.
Bit 0 = BER threshold fault.
Where: Character “e”: Common equipment fault status character 1.
Bit 6 = 1 always.
Bit 5 = M&C fault.
Bit 4 = Interface fault.
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of common
equipment stored faults.
Where: Character “f”: Common equipment fault status character 2.
Bit 6 = 1 always.
Bit 5 = Battery fault.
Bit 4 = +5V fault.
Bit 3 = +12V fault.
Bit 2 = -12V fault.
Bit 1 = Transmit clock loss fault (DS-1 only).
Bit 0 = not used.
Where: Character “g”: Interface receive side faults character 1.
Bit 6 = 1 always.
Bit 5 = Buffer underflow.
Bit 4 = Buffer overflow.
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of interface receive
side stored faults.
B.1.4.17 Change Status
This command indicates that a change has or has not occurred on either the BCS_ or the
BCSF_ response since the last BCS_ or BCSF_ poll.
Command:
Response:
<add/CS_”cr”
>add/CS_x”cr””lf”]
Where: x =
“@” = no change since last CS_ poll.
“A” = BCS_ response has changed since last CS_ poll.
“B” = BCSF_ response has changed since last CS_ poll.
“C” = Both responses have changed since last CS_ poll.
Rev. 6
B–31
Remote Control Operation
SDM-650B Satellite Modem
B.1.4.18 Equipment Type
This command returns the equipment model number and M&C firmware version number.
Command:
Response:
<add/ET_”cr”
>add/ET_SDM650_x.xxx”cr””lf”]
Where: x.xxx = M&C firmware version.
B–32
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2 Asynchronous Overhead Interface Support Option
This section describes the remote control operation of the SDM-650B with the
asynchronous overhead channel unit option installed:
•
•
Firmware number:
Software version:
FW/0713-34L
4.12A
B.2.1 General
Remote controls and status information are transferred via an RS-485 (optional RS-232-C)
serial communications link.
Commands and data are transferred on the remote control communications link as
US ASCII-encoded character strings.
The remote communications link is operated in a half-duplex mode.
Communications on the remote link are initiated by a remote controller or terminal. The
modem never transmits data on the link unless it is commanded to do so.
B.2.2 Message Structure
The ASCII character format used requires 11 bits/character:
•
•
•
•
1 start bit
7 information bits
1 parity bit (odd/even)
2 stop bits
Messages on the remote link fall into the categories of commands and responses.
Commands are messages which are transmitted to a satellite modem, while responses are
messages returned by a satellite modem in response to a command.
The general message structure is as follows:
•
•
•
•
Rev. 6
Start Character
Device Address
Command/Response
End of Message Character
B–33
Remote Control Operation
SDM-650B Satellite Modem
B.2.2.1 Start Character
A single character precedes all messages transmitted on the remote link. This character flags
the start of a message. This character is:
•
•
“<” for commands
“>” for responses
B.2.2.2 Device Address
The device address is the address of the one satellite modem which is designated to receive
a transmitted command, or which is responding to a command.
Valid device addresses are 1 to 3 characters long, and in the range of 1 to 255. Address 0 is
reserved as a global address which simultaneously addresses all devices on a given
communications link. Devices do not acknowledge global commands.
Each satellite modem which is connected to a common remote communications link must
be assigned its own unique address. Addresses are software selectable at the modem, and
must be in the range of 1 to 255.
B–34
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.2.3 Command/Response
The command/response portion of the message contains a variable length character
sequence which conveys command and response data.
If a satellite modem receives a message addressed to it which does not match the
established protocol or can not be implemented, a negative acknowledgment message is
sent in response. This message is:
•
>add/?ER1_PARITY ERROR”cr””lf”]
(Error message for parity errors.)
•
>add/?ER2_INVALID PARAMETER”cr””lf”]
(Error message for a recognized command which can not be implemented or has parameters
which are out of range.)
•
>add/?ER3_UNRECOGNIZABLE COMMAND”cr””lf”]
(Error message for unrecognizable command or bad command syntax.)
•
>add/?ER4_MODEM IN LOCAL MODE”cr””lf”]
(Modem in local error, use the REM command to go to remote mode.)
•
>add/?ER5_HARD CODED PARAMETER”cr””lf”]
(Error message indicating that the parameter is hardware dependent and may not be changed
remotely.)
Note: “add” is used to indicate a valid 1 to 3 character device address in the range
between 1 and 255.
B.2.2.4 End Character
Each message is ended with a single character which signals the end of the message:
•
•
Rev. 6
“cr”
“]”
Carriage return character for commands
End bracket for responses
B–35
Remote Control Operation
SDM-650B Satellite Modem
B.2.3 Modulator Configuration Commands
B.2.3.1 Set Modulator Frequency
Command:
Response:
<add/MF_nnn.nnnn”cr”
>add/MF_nnn.nnnn”cr”
RF_OFF”cr””lf”]
Status Only:
Response:
<add/MF_”cr”
>add/MF_nnn.nnnn”cr””lf”]
Where: nnn.nnnn = 50.0000 to 90.0000, and 100.0000 to 180.0000 for the
140 MHz modulator.
Note: When modulator frequency is changed, the RF output is switched OFF.
B.2.3.2 Set RF Output
Command:
Response:
<add/RF_xxx”cr”
>add/RF_xxx”cr””lf”]
Status Only:
Response:
<add/RF_”cr”
>add/RF_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.2.3.3 Set Modulator Power Offset
Command:
Response:
<add/MPO_snn.n”cr”
>add/MPO_snn.n”cr””lf”]
Status Only:
Response:
<add/MPO_”cr”
>add/MPO_snn.n”cr””lf”]
Where: snn.n = +20.0 to -20.0, in 0.5 dB increments.
Notes:
1. This will be the highest modulator power that will be displayed and programmed.
2. Use the MOP_ command to change the modulator output power.
B–36
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.3.4 Set Modulator Output Power Level
Command:
Response:
<add/MOP_snn.n”cr”
>add/MOP_snn.n”cr””lf”]
Status Only:
Response:
<add/MOP_”cr”
>add/MOP_snn.n”cr””lf”]
Where:
snn.n = +20.0 to -45.0, in 0.5 dB increments for 140 MHz modulator.
snn.n = +20.0 to -30.0, in 0.5 dB increments for 70 MHz modulator.
Notes:
1. Must be within 25.0 dB of the modulator power offset value (see MPO_) for the
140 MHz modulator, and within 10.0 dB of the modulator power offset for the
70 MHz modulator.
2. When local AUPC enable is programmed ON, the (MOP) Modulator Output
Power command is not allowed; only MOP status is allowed. See “LPC_”
command.
Rev. 6
B–37
Remote Control Operation
SDM-650B Satellite Modem
B.2.3.5 Modulator Rate
The modulator has four symbol rate filters. Each filter is for a specific symbol rate. The
data rate and coder rate for each filter must be established upon initial modulator
installation, and when circumstances indicate the need to do so.
Filters are designated as A, B, C, and D. If a filter is not physically present in the system,
it may be assigned “N/A” (not assigned).
Additionally, filters which are factory programmed may not be remotely programmed,
and will return the “error 5” message when a programming command is issued.
Note: Variable rate modulator option:
1. Modulators with the variable rate option installed may have four preprogrammed
rates available by using the filter rate assignment commands. These rates are
selected using the standard “SMRx_” commands.
2. Modems that have the variable rate option installed will also respond to the
special “SMRV_” command.
B.2.3.5.1 Modulator Filter Rate Assignment
Command:
Response:
<add/AMRx_nnn_mmmm.m”cr”
>add/AMRx_nnn_mmmm.m”cr””lf”]
Status Only:
Response:
<add/AMRx_”cr”
>add/AMRx_nnn_mmmm.m”cr””lf”]
Where:
x = A, B, C, or D (Filter designator).
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
Example:
Command:
Response:
B–38
<add/AMRx_N/A”cr”
>add/AMRx_N/A”cr””lf”]
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.3.5.2 Select Modulator Rate
Command:
Response:
<add/SMRx_”cr”
>add/SMRx_”cr”
RF_OFF”cr””lf”]
Status Only:
(See MR command.)
Where: x = A, B, C, or D (Filter designator).
Notes:
1. Setting the modulator turns OFF the RF transmitter.
2. If the modem is commanded to a filter (rate) which is not assigned (N/A), the
“error 2” message will be returned.
B.2.3.5.3 Select Modulator Rate Variable
Note: This command is only applicable for the variable rate option.
Command:
Response:
<add/SMRV_nnn_mmmm.m”cr”
>add/SMRV_nnn_mmmm.m”cr””lf”]
RF_OFF”cr””lf”]
Status Only:
(See MR command.)
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: Setting the modulator turns OFF the RF transmitter.
B.2.3.6 Scrambler Enable
Command:
Response:
<add/SE_xxx”cr”
>add/SE_xxx”cr””lf”]
Status Only:
Response:
<add/SE_”cr”
>add/SE_xxx”cr””lf”]
Where: xxx = ON or OFF.
Rev. 6
B–39
Remote Control Operation
SDM-650B Satellite Modem
B.2.3.7 Differential Encoder Enable
Command:
Response:
<add/DENC_xxx”cr”
>add/DENC_xxx”cr”lf”]
Status Only:
Response:
<add/DENC_”cr”
>add/DENC_xxx”cr”lf”]
Where: xxx = ON or OFF.
B.2.4 Demodulator Configuration Commands
B.2.4.1 Set Demodulator Frequency
Command:
Response:
<add/DF_nnn.nnnn”cr”
>add/DF_nnn.nnnn”cr””lf”]
Status Only:
Response:
<add/DF_”cr”
>add/DF_nnn.nnnn”cr””lf”]
Note: nnn.nnnn = 50.0000 to 90.0000, and 100.0000 to 180.0000 for the 140 MHz
modulator.
B.2.4.2 Demodulator Rate
The demodulator has four symbol rate filters. Each filter is for a specific symbol rate. The
data rate and decoder rate for each filter must be established upon initial demodulator
installation, and when circumstances indicate the need to do so.
Filters are designated as A, B, C, and D. If a filter is not physically present in the system,
it may be assigned “N/A” (not assigned).
Additionally, filters which are factory programmed may not be remotely programmed,
and will return the “error 5” message when a programming command is issued.
Note: For variable rate demodulator option:
1. Demodulators with the variable rate option installed may have four
preprogrammed rates available by using the filter rate assignment commands.
These rates are selected using the standard “SDRx_” commands.
2. Modems that have the variable rate option installed will also respond to the
special “SDRV_” command. This allows for truly variable rate control, while
maintaining compatibility with previous systems.
B–40
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.4.2.1 Demodulator Filter Rate Assignment
Command:
Response:
<add/ADRx_nnn_mmmm.m”cr”
>add/ADRx_nnn_mmmm.m”cr””lf”]
Status Only:
Response:
<add/ADRx_”cr”
>add/ADRx_nnn_mmmm.m”cr””lf”]
Where:
x = A, B, C, or D (Filter designator).
nnn = 1/2, 3/4, 7/8, or BP12 (Decoder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
Example:
Command:
Response:
<add/ADRx_N/A”cr”
>add/ADRx_N/A”cr””lf”]
B.2.4.2.2 Select Demodulator Rate
Command:
Response:
<add/SDRx_”cr”
>add/SDRx_”cr””lf”]
Status Only:
(See DR command.)
Where: x = A, B, C, or D (Filter designator).
Note: If the modem is commanded to a filter (rate) which is not assigned (N/A), the
error 2 message will be returned.
B.2.4.2.3 Select Demodulator Rate Variable
Note: This command is only applicable for the variable rate option.
Command:
Response:
<add/SDRV_nnn_mmmm.m”cr”
>add/SDRV_nnn_mmmm.m”cr””lf”]
Status Only:
(See DR command.)
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Rev. 6
B–41
Remote Control Operation
SDM-650B Satellite Modem
B.2.4.3 Descramble Enable
Command:
Response:
<add/DE_xxx”cr”
>add/DE_xxx”cr””lf”]
Status Only:
Response:
<add/DE_”cr”
>add/DE_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.2.4.4 RF Loopback
Command:
Response:
<add/RFL_xxx”cr”
>add/RFL_xxx”cr””lf”]
Status Only:
Response:
<add/RFL_”cr”
>add/RFL_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.2.4.5 IF Loopback
Command:
Response:
<add/IFL_xxx”cr”
>add/IFL_xxx”cr””lf”]
Status Only:
Response:
<add/IFL_”cr”
>add/IFL_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.2.4.6 BER Threshold
Command:
Response:
<add/BERT_xxxx”cr”
>add/BERT_xxxx”cr””lf”]
Status Only:
Response:
<add/BERT_”cr”
>add/BERT_xxxx”cr””lf”]
Where: xxxx = NONE or 1E-n (n = 3, 4, 5, 6, 7, or 8 exponent of threshold).
B–42
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.4.7 Sweep Reacquisition
This command is used to specify time duration of the reacquisition mode.
The sweep is reduced to ± 2500 Hz of the last known lock point. Use of this function may
reduce reacquisition times at low data rates.
To inhibit the sweep reacquisition mode, set “SR” to 0 seconds.
Command:
Response:
<add/SR_xxx”cr”
>add/SR_xxx”cr””lf”]
Status Only:
Response:
<add/SR_”cr”
>add/SR_xxx”cr””lf”]
Where: xxx = 0 to 999 (number of seconds).
B.2.4.8 Fast Acquisition Mode
This command is used to enable or disable fast acquisition and directed sweep modes of
operation.
When fast acquisition is enabled, the fast acquisition algorithm (which requires hardware
calibration) is used for acquisition of receive symbol rates of 128 kbit/s or lower.
However, if the sweep range is set to less than 50 kHz, acquisition will be dictated by the
directed sweep specifications, and the fast acquisition algorithm will not be used.
The directed sweep functions are also available when fast acquisition is enabled. Directed
sweep provides three commands for manipulating the acquisition process. These
commands are:
•
•
•
“SCF_” (sweep center frequency)
“SWR_” (sweep range)
“SD_” (sweep direction)
Command:
Response:
<add/FAM_xxx”cr”
>add/FAM_xxx”cr””lf”]
Status Only:
Response:
<add/FAM_”cr”
>add/FAM_xxx”cr””lf”]
Where: xxx = ON or OFF (OFF disables fast acquisition and directed sweep modes).
Rev. 6
B–43
Remote Control Operation
SDM-650B Satellite Modem
B.2.4.8.1 Sweep Center Frequency
This command sets the sweep center frequency. During carrier acquisition, the sweep
starts at an offset which is one-half the currently programmed sweep range (SWR_) from
the sweep center frequency. The direction of the offset is determined by the currently
programmed sweep direction (SD_).
The sweep center frequency may be set in the range of +25000 to -25000 Hz.
Command:
Response:
<add/SCF_xnnnnn”cr”
>add/SCF_xnnnnn”cr””lf”]
Status Only:
Response:
<add/SCF_”cr”
>add/SCF_xnnnnn”cr””lf”]
Where:
x = + or - (sweep offset direction).
nnnnn = 0 to 25000.
Note: This command is only valid when fast acquisition is enabled. See the “FAM_”
command definition.
B.2.4.8.2 Sweep Width Range
This command sets the overall travel of the sweep during acquisition. The sweep width
may be set in the range of 0 to 50000 Hz.
Command:
Response:
<add/SWR_nnnnn”cr”
>add/SWR_nnnnn”cr””lf”]
Status Only:
Response:
<add/SWR_”cr””lf”
>add/SWR_nnnnn”cr””lf”]
Where: nnnnn = 0 to 50000.
Note: This command is only valid when fast acquisition is enabled. See the “FAM_”
command definition.
B–44
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.4.8.3 Sweep Direction
This command sets the direction of the sweep travel. “+” sets incremental sweep, while
“-” sets decremental sweep.
Command:
Response:
<add/SD_s”cr””lf”
>add/SD_s”cr””lf”]
Status Only:
Response:
<add/SD_”cr””lf”
>add/SD_s”cr””lf”]
Where: s = + or - (direction of sweep travel during acquisition).
Note: This command is only valid when fast acquisition is enabled. See the “FAM_”
command definition.
B.2.5 Interface Configuration Commands
B.2.5.1 Transmit Clock
Command:
Response:
<add/TC_xxx”cr”
>add/TC_xxx”cr””lf”]
Status Only:
Response:
<add/TC_”cr”
>add/TC_xxx”cr””lf”]
Where: xxx = INT or EXT.
B.2.5.2 Buffer Clock
Command:
Response:
<add/BC_xxx”cr”
>add/BC_xxx”cr””lf”]
Status Only:
Response:
<add/BC_”cr”
>add/BC_xxx”cr””lf”]
Where: xxx = SAT, INT, EXT, or REF.
Note: Available with buffer support hardware only.
Rev. 6
B–45
Remote Control Operation
SDM-650B Satellite Modem
B.2.5.3 Receive Clock
Command:
Response:
<add/RC_xxx”cr”
>add/RC_xxx”cr””lf”]
Status Only:
Response:
<add/RC_”cr”
>add/RC_xxx”cr””lf”]
Where: xxx = NRM or INV.
B.2.5.4 External Reference Frequency
Command:
Response:
<add/ERF_nnnnn”cr”
>add/ERF_nnnnn”cr””lf”]
Status Only:
Response:
<add/ERF_”cr”
>add/ERF_nnnnn”cr””lf”]
Where: nnnnn = 8 to 99992 (external reference frequency in kHz, must be a multiple of
8 kHz).
Note: Available with buffer support hardware only.
B.2.5.5 Interface Loopback
Command:
Response:
<add/ILB_xxx”cr”
>add/ILB_xxx”cr””lf”]
Status Only:
Response:
<add/ILB_”cr”
>add/ILB_xxx”cr””lf”]
Where: xxx = ON or OFF.
B.2.5.6 Baseband Loopback
Command:
Response:
<add/BBL_xxx”cr”
>add/BBL_xxx”cr””lf”]
Status Only:
Response:
<add/BBL_”cr”
>add/BBL_xxx”cr””lf”]
Where: xxx = ON or OFF.
B–46
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.5.7 Interface Coding Format Transmit
Command:
Response:
<add/ICFT_xxxx”cr”
>add/ICFT_xxxx”cr””lf”]
Status Only:
Response:
<add/ICFT_”cr”
>add/ICFT_xxxx”cr””lf”]
Where: xxxx = AMI, HDB3, B6ZS, or B8ZS.
B.2.5.8 Interface Coding Format Receive
Command:
Response:
<add/ICFR_xxxx”cr”
>add/ICFR_xxxx”cr””lf”]
Status Only:
Response:
<add/ICFR_”cr”
>add/ICFR_xxxx”cr””lf”]
Where: xxxx = AMI, HDB3, B6ZS, or B8ZS.
B.2.5.9 Interface Buffer Center
This command centers the interface buffer.
Command:
Response:
<add/IBC_”cr”
>add/IBC_”cr””lf”]
Note: Available with buffer support hardware only.
B.2.5.10 Interface Buffer Size
Command:
Response:
<add/IBS_nnnnnn”cr”
>add/IBS_nnnnnn”cr””lf”]
Status Only:
Response:
<add/IBS_”cr”
>add/IBS_nnnnnn”cr””lf”]
Where: nnnnnn = 32 to 262144, in 16-bit increments.
Note: Available with buffer support hardware only.
Rev. 6
B–47
Remote Control Operation
SDM-650B Satellite Modem
B.2.5.11 Transmit Overhead Baud Rate
Command:
Response:
<add/TOBR_nnnnn”cr”
>add/TOBR_nnnnn”cr””lf”]
Status Only:
Response:
<add/TOBR_”cr”
>add/TOBR_nnnnn”cr””lf”]
Where: nnnnn = 110, 150, 300, 600, 1200, 2400, 4800, 9600, 19200, or 38400.
B.2.5.12 Receive Overhead Baud Rate
Command:
Response:
<add/ROBR_nnnnn”cr”
>add/ROBR_nnnnn”cr””lf”]
Status Only:
Response:
<add/ROBR_”cr”
>add/ROBR_nnnnn”cr””lf”]
Where: nnnnn = 110, 150, 300, 600, 1200, 2400, 4800, 9600, 19200, or 38400.
B.2.5.13 Overhead Channels Character Length
Command:
Response:
<add/OCCL_n”cr”
>add/OCCL_n”cr””lf”]
Status Only:
Response:
<add/OCCL_”cr”
>add/OCCL_n”cr””lf”]
Where: n = 5, 6, 7, or 8 (characters).
B.2.5.14 Overhead Channels Stop Bits
Command:
Response:
<add/OCSB_n”cr”
>add/OCSB_n”cr””lf”]
Status Only:
Response:
<add/OCSB_”cr”
>add/OCSB_n”cr””lf”]
Where: n = 1 or 2 (stop bits).
B–48
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.5.15 Overhead Channels Parity
Command:
Response:
<add/OCP_xxxx”cr”
>add/OCP_xxxx”cr””lf”]
Status Only:
Response:
<add/OCP_”cr”
>add/OCP_xxxx”cr””lf”]
Where: xxxx = ODD, EVEN, or NONE.
B.2.5.16 Interface Substitution Pattern (Transmit 2047 Pattern)
Command:
Response:
<add/ISP_xxx”cr”
>add/ISP_xxx”cr””lf”]
Status Only:
Response:
<add/ISP_”cr”
>add/ISP_xxx”cr””lf”]
Where: xxx = ON or OFF (transmit 2047 pattern generation).
B.2.6 System Commands/Responses
B.2.6.1 Time of Day
Command:
Response:
<add/TIME_hh:mmxx”cr”
>add/TIME_hh:mmxx”cr””lf”]
Status Only:
Response:
<add/TIME_”cr”
>add/TIME_hh:mmxx”cr””lf”]
Where:
hh = hours.
mm = minutes.
xx = AM or PM.
Example: Set modem 67 time to 10:45 PM.
Command:
Response:
Rev. 6
<67/TIME_10:45PM”cr”
>67/TIME_10:45PM”cr””lf”]
B–49
Remote Control Operation
SDM-650B Satellite Modem
B.2.6.2 Date
Command:
Response:
<add/DATE_mm/dd/yy”cr”
>add/DATE_mm/dd/yy”cr””lf”]
Status Only:
Response:
<add/DATE_”cr”
>add/DATE_mm/dd/yy”cr””lf”]
Where:
mm = month.
dd = day.
yy = year.
Example: Set modem 235 date to 11/30/87.
Command:
Response:
<235/DATE_11/30/87”cr”
>235/DATE_11/30/87”cr””lf”]
B.2.6.3 Remote
This command configures the modem for remote operation.
The modem will respond to any status request at any time. However, the modem must be
in “Remote Mode” to change configuration parameters.
Command:
Response:
<add/REM_”cr”
>add/REM_”cr””lf”]
B.2.6.4 Clear Stored Faults
This command is used to clear all stored faults logged by the modem.
Command:
Response:
B–50
<add/CLSF_”cr”
>add/CLSF_”cr””lf”]
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.6.5 Modem Operation Mode
This command configures the modem for simplex or duplex operation modes.
When transmit-only mode is selected, receive faults are inhibited. When receive-only
mode is selected, transmit faults are inhibited.
Command:
Response:
<add/MOM_xxxxxxx”cr”
>add/MOM_xxxxxxx”cr””lf”]
Status Only:
Response:
<add/MOM_”cr”
>add/MOM_xxxxxxx”cr””lf”]
Where: xxxxxxx = TX_ONLY, RX_ONLY, or DUPLEX.
B.2.7 Automatic Uplink Power Control (AUPC) Configuration Commands
B.2.7.1 Local Modem AUPC Commands
B.2.7.1.1 Local AUPC Enable
Command:
Response:
<add/LPC_xxx”cr”
>add/LPC_xxx”cr””lf”]
Status Only:
Response:
<add/LPC_”cr”
>add/LPC_xxx”cr””lf”]
Where: xxx = ON or OFF (local AUPC enable).
Note: When programmed ON, the MOP command is not allowed; only MOP status is
allowed.
B.2.7.1.2 Nominal AUPC Power Level
Command:
Response:
<add/NOMP_-nn.n”cr”
>add/NOMP_-nn.n”cr””lf”]
Status Only:
Response:
<add/NOMP_”cr”
>add/NOMP_-nn.n”cr””lf”]
Where: nn.n = 5.0 to 30.0, in 0.5 increments (power in dBm).
Rev. 6
B–51
Remote Control Operation
SDM-650B Satellite Modem
B.2.7.1.3 Maximum AUPC Power Limit
Command:
Response:
<add/MAXP_-nn.n”cr”
>add/MAXP_-nn.n”cr””lf”]
Status Only:
Response:
<add/MAXP_”cr”
>add/MAXP_-nn.n”cr””lf”]
Where: nn.n = 5.0 to 30.0, in 0.5 increments (power in dBm).
B.2.7.1.4 Minimum AUPC Power Limit
Command:
Response:
<add/MINP_-nn.n”cr”
>add/MINP_-nn.n”cr””lf”]
Status Only:
Response:
<add/MINP_”cr”
>add/MINP_-nn.n”cr””lf”]
Where: nn.n = 5.0 to 30.0, in 0.5 increments (power in dBm).
B.2.7.1.5 Eb/N0 Target AUPC Set Point
Command:
Response:
<add/ENSP_n.n”cr”
>add/ENSP_n.n”cr””lf”]
Status Only:
Response:
<add/ENSP_”cr”
>add/ENSP_n.n”cr””lf”]
Where: n.n = 3.2 to 9.7, in 0.1 increments (Eb/N0 in dB).
B.2.7.1.6 Maximum AUPC Tracking Rate
Command:
Response:
<add/MAXT_n.n”cr”
>add/MAXT_n.n”cr””lf”]
Status Only:
Response:
<add/MAXT_”cr”
>add/MAXT_n.n”cr””lf”]
Where: n.n = 0.5 to 6.0, in 0.5 increments (max. tracking rate in dBm/minute).
B–52
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.7.1.7 AUPC Local Carrier Loss Action
Command:
Response:
<add/LCL_xxxx”cr”
>add/LCL_xxxx”cr””lf”]
Status Only:
Response:
<add/LCL_”cr”
>add/LCL_xxxx”cr””lf”]
Where: xxxx = HOLD, NOM, or MAX (power level setting when local carrier loss).
B.2.7.1.8 AUPC Remote Carrier Loss Action
Command:
Response:
<add/RCL_xxxx”cr”
>add/RCL_xxxx”cr””lf”]
Status Only:
Response:
<add/RCL_”cr”
>add/RCL_xxxx”cr””lf”]
Where: xxxx = HOLD, NOM, or MAX (power level setting when remote carrier loss).
B.2.7.2 Remote Modem AUPC Commands
Notes:
1. Always wait three seconds between consecutive remote modem command/status
polls.
2. On status-only commands, the first time polled will cause a “???” instead of the
regular data being returned. Retrying a second time (Note 1, in effect), will return
a valid status response.
3. A status poll always returns the data from the last poll.
B.2.7.2.1 Remote AUPC Enable
Command:
Response:
<add/RPC_xxx”cr”
>add/RPC_xxx”cr””lf”]
Status Only:
Response:
<add/RPC_”cr”
>add/RPC_xxx”cr””lf”]
Where: xxx = ON or OFF (remote AUPC enable).
Rev. 6
B–53
Remote Control Operation
SDM-650B Satellite Modem
B.2.7.2.2 Remote Interface Substitution Pattern (Transmit 2047
Pattern)
Command:
Response:
<add/RISP_xxx”cr”
>add/RISP_xxx”cr””lf”]
Status Only:
Response:
<add/RISP_”cr”
>add/RISP_xxx”cr””lf”]
Where: xxx = ON or OFF (remote transmit 2047 pattern enable).
B.2.7.2.3 Remote Interface Baseband Loopback
Command:
Response:
<add/RBBL_xxx”cr”
>add/RBBL_xxx”cr””lf”]
Status Only:
Response:
<add/RBBL_”cr”
>add/RBBL_xxx”cr””lf”]
Where: xxx = ON or OFF (remote baseband loopback enable).
B.2.7.2.4 Remote Interface Read Error Status (Received 2047
Pattern)
This command returns 2047 BER from the remote AUPC modem. If data is not valid, the
message “No_Data” is returned instead of BER data.
Command:
Response:
<add/RRES_”cr”
>add/RRES_nE-e”cr””lf”]
Where:
n = 1 to 9 (error rate number).
e = 2 to 6 (exponent).
Example:
Command:
Response:
B–54
<add/RRES_”cr”
>add/RRES_2E-6”cr””lf”]
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.8 Status Commands/Responses
B.2.8.1 Configuration Status
B.2.8.1.1 Modulator/Coder Configuration Status
The Modulator/Coder configuration status command causes a block of data to be returned
by the addressed modem. The block of data reflects the current configuration status of the
Modulator/Coder.
Command:
Response:
Rev. 6
<add/MCS_”cr”
>add/MCS_”cr”
RF_xxx”cr”
MF_nnn.nnnn”cr”
MPO_snn.n”cr”
MOP_snn.n”cr”
MR_nnn_mmmm.m”cr”
AMRA_nnn_mmmm.m”cr”
AMRB_nnn_mmmm.m”cr”
AMRC_nnn_mmmm.m”cr”
AMRD_nnn_mmmm.m”cr”
SE_xxx”cr”
COM_xxx”cr”
DENC_xxx”cr”
TC_xxx”cr”
AMRV_nnn.mmmm.m”cr””lf”]
RF Output (ON/OFF)
Modulator Frequency
Modulator Power Offset
Modulator Output Power
Modulator Rate
Filter “A” Assignment
Filter “B” Assignment
Filter “C” Assignment
Filter “D” Assignment
Scrambler Enable (ON/OFF)
Carrier Only Mode (ON/OFF)
Differential Encoder (ON/OFF)
Transmit Clock (INT/EXT)
Modulator Variable Rate Assignment
(Variable Rate Option Only)
B–55
Remote Control Operation
SDM-650B Satellite Modem
B.2.8.1.2 Modulator/Coder Configuration Program
This command is used by the SMS-658 M:N protection switch to collect information that
is necessary to configure backup modems.
Command:
Response:
(See Note 1)
(See Note 2)
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 1)
<add/MCP_”cr”
>add/MCP_”cr”
MF_nnn.nnnn”cr”
MPO_snn.n”cr”
LPC_xxx”cr”
MOP_snn.n”cr”
MR_nnn_mmmm.m”cr”
SE_xxx”cr”
DENC_xxx”cr”
TC_xxx”cr”
BBL_xxx”cr”
ILB_xxx”cr”
ICFT_xxxx”cr”
TOBR_nnnnn”cr”
OCCL_n”cr”
OCSB_n”cr”
OCP_xxxx”cr”
ISP_xxx”cr”
LPC_xxx”cr”
NOMP_-nn.n”cr”
MINP_-nn.n”cr”
MAXP_-nn.n”cr”
LCL_xxxx”cr”
RCL_xxxx”cr”
RF_xxx”cr””lf”]
Modulator Frequency
Modulator Power Offset
Local AUPC Enable (ON/OFF)
Modulator Output Power
Modulator Rate
Scrambler Enable (ON/OFF)
Differential Encoder (ON/OFF)
Transmit Clock (INT/EXT)
Baseband Loopback (ON/OFF)
Interface Loopback (ON/OFF)
Coding Format Transmit
(AMI/HDB3/B6ZS/B8ZS)
Transmit Overhead Baud Rate
Overhead Channel Character Length
Overhead Channel Stop Bits
Overhead Channel Parity
Interface Substitution Pattern 2047 (ON/OFF)
Local AUPC Enable (ON/OFF)
Nominal Power Value (-5.0 to -30.0)
Minimum Power Limit (-5.0 to -30.0)
Maximum Power Value (-5.0 to -30.0)
Local Carrier Loss (HOLD, NOM, MAX)
Remote Carrier Loss (HOLD, NOM, MAX)
RF Output (ON/OFF)
Notes:
1. Available with AUPC support hardware only.
2. Only returned if local AUPC is disabled (OFF).
B–56
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.8.1.3 Demodulator/Decoder Configuration Status
The Demodulator/Decoder configuration status command causes a block of data to be
returned by the addressed modem. The block of data reflects the current configuration of
the demod.
Command:
Response:
(See Note)
(See Note)
(See Note)
<add/DCS_”cr”
>add/DCS_”cr”
DF_nnn.nnnn”cr”
DR_nnn_mmmm.m”cr”
ADRA_nnn_mmmm.m”cr”
ADRB_nnn_mmmm.m”cr”
ADRC_nnn_mmmm.m”cr”
ADRD_nnn_mmmm.m”cr”
DE_xxx”cr”
RFL_xxx”cr”
BERT_xxxx”cr”
SR_xxx”cr”
IFL_xxx”cr”
SCF_snnnnn”cr”
SWR_nnnnn”cr”
SD_s”cr”
FAM_xxx”cr”
ADRV_nnn.mmmm.m”cr””lf”]
Demodulator Frequency
Demodulator Data Rate
Filter “A” Assignment
Filter “B” Assignment
Filter “C” Assignment
Filter “D” Assignment
Descrambler Enable (ON/OFF)
RF Loopback (ON/OFF)
BER Threshold
Sweep Reacquisition (seconds)
IF Loopback (ON/OFF)
Sweep Center Frequency
Sweep Width
Sweep Direction
Fast Acquisition Mode
Demodulator Variable Rate Assignment
(Variable Rate Option Only)
Note: “SCF_”, “SWR_”, and “SD_” responses are returned only when fast acquisition is
enabled. See the “FAM_” command definition.
Rev. 6
B–57
Remote Control Operation
SDM-650B Satellite Modem
B.2.8.1.4 Demodulator/Decoder Configuration Program
This command is used by the SMS-658 M:N protection switch to collect information that
is necessary to configure backup modems.
Command:
Response:
(See Note 2)
(See Note 2)
(See Note 2)
(See Note 1)
(See Note 1)
(See Note 1)
(See Note 3)
(See Note 3)
<add/DCP_”cr”
>add/DCP_”cr”
IFL_xxx”cr”
RFL_xxx”cr”
DF_nnn.nnnn”cr”
DR_nnn_mmmm.m”cr”
DE_xxx”cr”
BERT_xxxx”cr”
SR_xxx”cr”
FAM_xxx”cr”
SCF_snnnnn”cr”
SWR_nnnnn”cr”
SD_s”cr”
RC_xxx”cr”
BBL_xxx”cr”
ILB_xxx”cr”
ICFR_xxxx”cr”
ROBR_nnnnn”cr”
OCCL_n”cr”
OCSB_n”cr”
OCP_xxxx”cr”
ERF_nnnnn”cr”
BC_xxx”cr”
IBS_nnnnnn”cr”
ENSP_n.n”cr”
MAXT_n.n”cr””lf”]
IF Loopback (ON/OFF)
RF Loopback (ON/OFF)
Demodulator Frequency
Demodulator Data Rate
Descrambler Enable (ON/OFF)
BER Threshold
Sweep Reacquisition (seconds)
Fast Acquisition Mode
Sweep Center Frequency
Sweep Width
Sweep Direction
Receive Clock (NRM/INV)
Baseband Loopback (ON/OFF)
Interface Loopback (ON/OFF)
Coding Format Receive
(AMI/HDB3/B6ZS/B8ZS)
Receive Overhead Baud Rate
Overhead Channel Character Length
Overhead Channel Stop Bits
Overhead Channel Parity
External Reference Frequency
Buffer Clock (INT/EXT/SAT/REF)
Interface Buffer Size
Eb/N0 Target Set Point (3.2 to 9.7)
Max. Tracking Rate (0.5 to 6.0)
Notes:
1. Available with buffer support hardware only.
2. “SCF_”, “SWR_”, and “SD_” responses are returned only when fast acquisition
is enabled. See the “FAM_” command definition.
3. Available with AUPC support hardware only.
B–58
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.8.1.5 Interface Configuration Status
The interface configuration status command causes a block of data to be returned by the
addressed modem. The block reflects the current configuration of the interface.
Command:
Response:
<add/ICS_”cr”
>add/ICS_”cr”
TC_xxx”cr”
RC_xxx”cr”
BBL_xxx”cr”
ILB_xxx”cr”
ICFT_xxxx”cr”
ICFR_xxxx”cr”
(See Note 2)
(See Note 1)
(See Note 1)
(See Note 1)
TOBR_nnnnn”cr”
ROBR_nnnnn”cr”
OCCL_n”cr”
OCSB_n”cr”
OCP_xxxx”cr”
ISP_xxx”cr”
ERF_nnnnn”cr”
BC_xxx”cr”
IBS_nnnnnn”cr””lf”]
Transmit Clock (INT/EXT)
Receive Clock (NRM/INV)
Baseband Loopback (ON/OFF)
Interface Loopback (ON/OFF)
Coding Format Transmit
(AMI/HDB3/B6ZS/B8ZS)
Coding Format Receive
(AMI/HDB3/B6ZS/B8ZS)
Transmit Overhead Baud Rate
Receive Overhead Baud Rate
Overhead Channel Character Length
Overhead Channel Stop Bits
Overhead Channel Parity
Interface Substitution Pattern 2047 (ON/OFF)
External Reference Frequency
Buffer Clock (INT, EXT, REF, SAT)
Interface Buffer Size
Notes:
1. Available with buffer support hardware only.
2. Available with AUPC support hardware only.
B.2.8.1.6 AUPC Configuration Status
The AUPC interface configuration status command causes a block of data to be returned
by the addressed modem. The block reflects the current configuration of the interface.
Command:
Response:
Rev. 6
<add/ACS_”cr”
>add/ACS_”cr”
LPC_xxx”cr”
NOMP_-nn.n”cr”
MINP_-nn.n”cr”
MAXP_-nn.n”cr”
ENSP_n.n”cr”
MAXT_n.n”cr”
LCL_xxxx”cr”
RCL_xxxx”cr”
ISP_xxx”cr””lf”]
Local AUPC Enable (ON/OFF)
Nominal Power Value (-5.0 to -30.0)
Minimum Power Limit (-5.0 to -30.0)
Maximum Power Value (-5.0 to -30.0)
Eb/N0 Target Set Point (3.2 to 9.7)
Max. Tracking Rate (0.5 to 6.0)
Local Carrier Loss (HOLD, NOM, MAX)
Remote Carrier Loss (HOLD, NOM, MAX)
Interface Substitution Pattern 2047 (ON/OFF)
B–59
Remote Control Operation
SDM-650B Satellite Modem
B.2.8.2 Modem Faults Status (Summary)
This command returns the current overall fault conditions of the modem.
Command:
Response:
<add/MFS_”cr”
>add/MFS_”cr”
DMD_xxx”cr”
MOD_xxx”cr”
CEQ_xxx”cr”
ITX_xxx”cr”
IRX_xxx”cr””lf”]
Demodulator (FLT/OK)
Modulator (FLT/OK)
Common Equipment (FLT/OK)
Interface Transmit Side (OK/FLT)
Interface Receive Side (OK/FLT)
B.2.8.3 Modulator Status
The modulator status is returned as a block of data which indicates general status
information.
Command:
Response:
<add/MS_”cr”
>add/MS_”cr”
RF_xxx”cr”
MOD_xxx”cr”
AGC_xxx”cr”
SYN_xxx”cr”
BCLK_xxx”cr”
TCLK_xxx”cr”
ICH_xxx”cr”
QCH_xxx”cr”
SFLT_xx”cr””lf”]
RF Output (ON/OFF) actual status not
configured
Module missing or will not program
(OK/FLT)
AGC Leveled (OK/FLT)
Carrier Synthesizer (OK/FLT)
Bit Clock (OK/FLT)
Transmit Clock (OK/FLT)
I Channel (OK/FLT)
Q Channel (OK/FLT)
Number of Stored Faults Logged (0 to 10)
B.2.8.4 Demodulator Status
The demodulator status is returned as a block of data which provides general status
information.
Command:
Response:
B–60
<add/DS_”cr”
>add/DS_”cr”
DMD_xxx”cr”
CD_xxx”cr”
SYN_xxx”cr”
DSCR_xxx”cr”
ICH_xxx”cr”
QCH_xxx”cr”
BCLK_xxx”cr”
BERT_xxx”cr”
RSL_-nn.ndBm”cr”
CSV_snnnnn”cr”
SFLT_xx”cr””lf”]
Demod Module (OK/FLT)
Carrier Detect (OK/FLT)
Synthesizer Lock (OK/FLT)
Descrambler (OK/FLT)
I Channel (OK/FLT)
Q Channel (OK/FLT)
Bit Clock (OK/FLT)
BER Threshold (OK/FLT)
Receive Signal Level (Level or No Data)
Current Sweep Value
Number of Stored Faults Logged (0 to 10)
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.8.5 Common Equipment Status
The common equipment status command causes a block of data to be returned which
indicates the status of the common equipment.
Command:
Response:
<add/CES_”cr”
>add/CES_”cr”
M&C_xxx”cr”
INT_xxx”cr”
BAT_xxx”cr”
PS1_xxx”cr”
PS2_xxx”cr”
PS3_xxx”cr”
MODE_xxxxxx”cr”
SW_x.xxx”cr”
SFLT_xx”cr””lf”]
Monitor and Control Module (OK/FLT)
Data Interface Module (OK/FLT)
Battery (OK/FLT)
+5V Power Supply (OK/FLT)
+12V Power Supply (OK/FLT)
-12V Power Supply (OK/FLT)
Mode (LOCAL or REMOTE)
Software Version
Number of Stored Faults Logged (0 to 10)
B.2.8.6 Interface Transmit Side Status
Command:
Response:
<add/ITXS_”cr”
>add/ITXS_”cr”
CLK_xxx”cr”
PLL_xxx”cr”
SFLT_xx”cr””lf”]
Selected Transmit Clock Activity
(OK/FLT)
Transmit Synthesizer PLL Lock
(OK/FLT)
Number of Stored Faults Logged (0 to 10)
B.2.8.7 Interface Receive Side Status
Command:
Response:
<add/IRXS_”cr”
>add/IRXS_”cr”
MUX_xxx”cr”
CLK_xxx”cr”
PLL_xxx”cr”
(See Note)
(See Note)
(See Note)
OVFL_xxx”cr”
UNFL_xxx”cr”
IBFS_nn%”cr”
SFLT_xx”cr””lf”]
MUX Lock (OK/FLT)
Selected Buffer Clock Activity
(OK/FLT)
Receive Synthesizer PLL Lock
(OK/FLT)
Buffer Overflow (OK/FLT)
Buffer Underflow (OK/FLT)
Interface Buffer Fill Status
Number of Stored Faults Logged (0 to 10)
Note: Available with buffer support hardware only.
Rev. 6
B–61
Remote Control Operation
SDM-650B Satellite Modem
B.2.8.8 Bit Error Rate Status
B.2.8.8.1 Raw BER
Command:
Response:
<add/RBER_”cr”
>add/RBER_nnnnE-4”cr””lf”]
Where:
nnnn = RBER.
nnnn = < 1.0 (lower limit).
Example: Request raw BER from modem 123.
Command:
Response:
<123/RBER_”cr”
>123/RBER_152E-4”cr””lf”]
Where: RBER = 0.0152 errors/bit.
Note: “No Data” is returned if no carrier is detected (decoder not locked).
B.2.8.8.2 Corrected BER
Command:
Response:
<add/CBER_”cr”
>add/CBER_nE-m”cr””lf”]
Example: Request corrected BER from modem 19.
Command:
Response:
<19/CBER_”cr”
>19/CBER_2E-5”cr””lf”]
Where: CBER = 0.00002 errors/bit.
Notes:
1. Corrected BER limits are lower < 1E-8, upper > 1E-3.
2. “No Data” is returned if no carrier is detected (decoder not locked).
B–62
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.8.9 Eb/N0
The Eb/N0 status command causes the Eb/N0 ratio to be returned. Eb/N0 is returned in dB.
Command:
Response:
<add/EBN0_”cr”
>add/EBN0_n.ndB”cr””lf”]
Example: Request Eb/N0 ratio from modem 2.
Command:
Response:
<2/EBN0_”cr”
>2/EBN0_6.2dB”cr””lf”]
Where: Eb/N0 = 6.2 dB.
Notes:
1. Eb/N0 limits are lower < 3.2 dB, upper > 9.7 dB.
2. “No Data” is returned if no carrier is detected (decoder not locked).
B.2.8.10 Modulator Rate
Command:
Response:
<add/MR_”cr”
>add/MR_nnn_mmmm.m”cr””lf”]
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
B.2.8.11 Demodulator Rate
Command:
Response:
<add/DR_”cr”
>add/DR_nnn_mmmm.m”cr””lf”]
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Decoder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
Rev. 6
B–63
Remote Control Operation
SDM-650B Satellite Modem
B.2.8.12 Receive Signal Level
Command:
Response:
<add/RSL_”cr”
>add/RSL_-nn.ndBm”cr””lf”]
B.2.8.13 Current Sweep Value
This command returns the current sweep value and the decoder lock status.
Command:
Response:
<add/CSV_”cr”
>add/CSV_snnnnn”cr”
CD_xxx”cr””lf”]
Where:
s = + or - (sweep offset direction).
nnnnn = 0 to 25000.
xxx = OK or FLT (decoder lock status OK or FAULT).
B.2.8.14 Interface Buffer Fill Status
Command:
Response:
<add/IBFS_”cr”
>add/IBFS_nn%”cr””lf”]
Where: nn = 1 to 99 (Relative to buffer depth).
Note: Available with buffer support hardware only.
B.2.8.15 Interface Read Error Status
This command returns 2047 BER. If data is not valid, the message “No_Data” is returned
instead of BER data.
Command:
Response:
<add/IRES_”cr”
>add/IRES_nE-e”cr””lf”]
Where:
n = 1 to 9 (error rate number).
e = 2 to 6 (exponent).
Example:
Command:
Response:
B–64
<add/IRES_”cr”
>add/IRES_2E-6”cr””lf”]
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.8.16 Stored Faults
Information on stored faults is returned when requested. If no stored fault exists for a
given fault number, the words “NO FAULT” will be returned instead of the normal
time/date status information.
The following symbols are commonly used to define the stored faults status commands:
•
•
•
•
•
•
•
#
hh
mm
ss
MM
DD
YY
Fault number (0 to 9), “0” is the first fault stored.
Hours in 24-hr. format.
Minutes.
Seconds.
Month.
Day.
Year.
B.2.8.16.1 Modulator Stored Faults
Command:
Response:
<add/MSF_#”cr”
>add/MSF_# hh:mm:ss MM/DD/YY”cr”
MOD_xxx”cr”
Module missing or will not program
(OK/FLT)
AGC_xxx”cr”
AGC Leveled (OK/FLT)
SYN_xxx”cr”
Carrier Synthesizer (OK/FLT)
BCLK_xxx”cr”
Bit Clock (OK/FLT)
TCLK_xxx”cr”
Transmit Clock (OK/FLT)
ICH_xxx”cr”
I Channel (OK/FLT)
QCH_xxx”cr””lf”]
Q Channel (OK/FLT)
B.2.8.16.2 Demodulator Stored Faults
Command:
Response:
Rev. 6
<add/DSF_#”cr”
>add/DSF_# hh:mm:ss MM/DD/YY”cr”
DMD_xxx”cr”
Demod Module (OK/FLT)
CD_xxx”cr”
Carrier Detect (OK/FLT)
SYN_xxx”cr”
Synthesizer Lock (OK/FLT)
DSCR_xxx”cr”
Descrambler (OK/FLT)
ICH_xxx”cr”
I Channel (OK/FLT)
QCH_xxx”cr”
Q Channel (OK/FLT)
BCLK_xxx”cr”
Bit Clock (OK/FLT)
BERT_xxx”cr””lf”]
BER Threshold (OK/FLT)
B–65
Remote Control Operation
SDM-650B Satellite Modem
B.2.8.16.3 Common Equipment Stored Faults
Command:
Response:
<add/CSF_#”cr”
>add/CSF_# hh:mm:ss
M&C_xxx”cr”
INT_xxx”cr”
BAT_xxx”cr”
PS1_xxx”cr”
PS2_xxx”cr”
PS3_xxx”cr””lf”]
MM/DD/YY”cr”
Monitor and Control Module (OK/FLT)
Data Interface Module (OK/FLT)
Battery (OK/FLT)
+5V Power Supply (OK/FLT)
+12V Power Supply (OK/FLT)
-12V Power Supply (OK/FLT)
B.2.8.16.4 Interface Transmit Side Stored Faults
Command:
Response:
<add/ITSF_#”cr”
>add/ITSF_# hh:mm:ss
CLK_xxx”cr”
PLL_xxx”cr””lf”]
MM/DD/YY”cr”
Selected Transmit Clock Activity
(OK/FLT)
Transmit Synthesizer PLL Lock
(OK/FLT)
B.2.8.16.5 Interface Receive Side Stored Faults
Command:
Response:
<add/IRSF_#”cr”
>add/IRSF_# hh:mm:ss
MUX_xxx”cr”
CLK_xxx”cr”
PLL_xxx”cr”
(See Note)
(See Note)
OVFL_xxx”cr”
UNFL_xxx”cr””lf”]
MM/DD/YY”cr”
MUX Lock (OK/FLT)
Selected Buffer Clock Activity
(OK/FLT)
Receive Synthesizer PLL Lock
(OK/FLT)
Buffer Overflow (OK/FLT)
Buffer Underflow (OK/FLT)
Note: Available with buffer support hardware only.
B–66
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
B.2.8.17 Bulk Consolidated Status
This command causes bulk modem status to be returned. To reduce the length of the
response, message parameter data are returned without identifiers.
However, parameter identification can be determined by order of return. Each status
parameter is terminated with a “,” (comma), except for the last parameter, which has the
standard message termination sequence (”cr””lf”]).
For standardization reasons, some parameters may not be implemented, but will retain the
terminating “,” (comma). Most of the data returned is formatted the same way as the
single command status request (refer to preceding sections).
Command:
Response:
<add/BCS_”cr”
>add/BCS_p1,p2,p3, . . . pn”cr””lf”]
Where: “pn” is the last parameter returned.
Parameter 1 (p1): Modulator RF output ON/OFF.
p1 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 2 (p2): Modulator IF frequency.
p2 = nnn.nnnn, where “nnn.nnnn” is the modulator IF frequency in MHz.
Parameter 3 (p3): Modulator output power level.
p3 = snn.n, where “snn.n” transmitter power output power level in dBm.
Parameter 4 (p4): Modulator rate currently programmed.
p4 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 5 (p5): Modulator filter A assignment.
p5 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 6 (p6): Modulator filter B assignment.
p6 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 7 (p7): Modulator filter C assignment.
p7 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 8 (p8): Modulator filter D assignment.
p8 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 9 (p9): Scrambler enable ON/OFF.
p9 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 10 (p10): Carrier only mode ON/OFF.
p10 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 11 (p11): Differential encoder enable ON/OFF.
p11 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 12 (p12): Demodulator IF frequency.
p12 = nnn.nnnn, where “nnn.nnnn” is the demodulator IF frequency in MHz.
Parameter 13 (p13): Demodulator rate currently programmed.
p13 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 14 (p14): Demodulator filter A assignment.
p14 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Rev. 6
B–67
Remote Control Operation
(See Note 2)
(See Note 2)
(See Note 2)
(See Note 1)
(See Note 1)
B–68
SDM-650B Satellite Modem
Parameter 15 (p15): Demodulator filter B assignment.
p15 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 16 (p16): Demodulator filter C assignment.
p16 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 17 (p17): Demodulator filter D assignment.
p17 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 18 (p18): Descrambler enable ON/OFF.
p18 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 19 (p19): RF loopback ON/OFF.
p19 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 20 (p20): BER threshold.
p20 = nnnn, where “nnnn” is the currently programmed BER threshold in the same
format as the single command “BERT_”.
Parameter 21 (p21): Sweep Reacquisition.
p21 = nn, where “nn” is the reacquisition parameter in seconds.
Parameter 22 (p22): IF loopback ON/OFF.
p22 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 23 (p23): Sweep center programmed.
p23 = snnnnn, where “s” is “+” or “-”, and “nnnnn” is the sweep center currently
programmed.
Parameter 24 (p24): Sweep width range.
p24 = nnnnn, where “nnnnn” is in the range of 0 to 50000 Hz.
Parameter 25 (p25): Sweep direction.
p25 = n, where “n” is “+” for positive, or “-” for negative sweep direction.
Parameter 26 (p26): MODEM REMOTE/LOCAL mode.
p26 = n, where “n” is “0” to indicate local, or “1” to indicate remote.
Parameter 27 (p27): Transmit clock source (Internal/External).
p27 = n, where “n” is “0” or “1” (“0” = INT,” “1” = EXT).
Parameter 28 (p28): Receive clock (Invert/Normal).
p28 = n, where “n” is “0” or “1” (“0” = NRM, “1” = INV).
Parameter 29 (p29): Baseband loopback ON/OFF.
p29 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 30 (p30): Interface loopback ON/OFF.
p30 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 31 (p31): TX Interface coding format (AMI/B8ZS/B6ZS/HDB3).
p31 = n, where “n” is “0”, “1”, “2”, or “3” (“0” = AMI, “1” = B6ZS, “2” = B8ZS,
“3” = HDB3).
Parameter 32 (p32): RX Interface coding format (AMI/B8ZS/B6ZS/HDB3).
p32 = n, where “n” is “0”, “1”, “2”, or “3” (“0” = AMI, “1” = B6ZS, “2” = B8ZS,
“3” = HDB3).
Parameter 33 (p33): Transmit Overhead Baud Rate.
p33 = nnnnn, where “nnnnn” is the currently programmed baud rate.
Parameter 34 (p34): Receive Overhead Baud Rate.
p34 = nnnnn, where “nnnnn” is the currently programmed baud rate.
Parameter 35 (p35): Overhead Channels Character Length.
p35 = n, where “n” is the currently programmed character length.
Parameter 36 (p36): Overhead Channels Stop Bits.
p36 = n, where “n” is the current number of stop bits programmed.
Parameter 37 (p37): Overhead Channels Parity.
p37 = xxxx, where “xxxx” is the currently programmed parity.
Parameter 38 (p38): External Reference Frequency.
p38 = nnnnn, where “nnnnn” is the assigned frequency in kHz.
Parameter 39 (p39): Buffer clock source (Internal/Reference/External/Satellite).
p39 = n, where “n” is “0”, “1”, “2”, or “3” (“0” = INT, “1” = REF, “2” = EXT,
“3” = SAT).
Rev. 6
SDM-650B Satellite Modem
(See Note 1)
Remote Control Operation
Parameter 40 (p40): Interface buffer size.
p40 = nnnnnn, where “nnnnnn” is the currently programmed buffer size in bits.
Notes:
1. Available with buffer support hardware only.
2. Parameters 23, 24, and 25 are only returned when fast acquisition is enabled. See
the “FAM_” command definition.
B.2.8.18 Bulk Consolidated Analog Status
This command is similar to the “BCS_” command, but returns modem analog parameters.
Command:
Response:
<add/BCAS_”cr”
>add/BCAS_p1,p2,p3, . . . pn”cr””lf”]
Where: “pn” is the last parameter returned.
(See Notes)
Parameter 1 (p1): Receive signal level.
p1 = -nn, where “nn” is the value of the receive signal level in dBm.
Parameter 2 (p2): Raw BER.
p2 = nnnnE-4, where “nnnn” is the raw bit errors in 10000 bits.
Parameter 3 (p3): Corrected BER.
p3 = nE-e, where “n” is the mantissa, and “e” is exponent (power of 10).
Parameter 4 (p4): Eb/N0.
p4 = n.n, where “n.n” is Eb/N0 in dB.
Parameter 5 (p5): Interface Buffer Fill Status.
p5 = nn, where “nn” is the fill status in percent.
Notes:
1. Parameters 1 through 5 are dependent on carrier acquisition. If the decoder is not
locked, empty data blocks are returned (,,,,,).
2. Available with buffer support hardware only.
Rev. 6
B–69
Remote Control Operation
SDM-650B Satellite Modem
B.2.8.19 Bulk Consolidated Status Faults
This command causes all modem fault status to be returned. To reduce the length of the
response, fault status is embedded into the bit structure of the characters that are returned.
Faults are indicated by a binary 1 in the designated bit position.
Command:
Response:
<add/BCSF_”cr”
>add/BCSF_abcdefghij”cr””lf”]
Where: Character “a”: Modulator fault status character 1.
Bit 6 = 1 always.
Bit 5 = Modulator fault.
Bit 4 = RF output status, actual not programmed status (1 = ON, 0 = OFF).
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of modulator stored
faults.
Where: Character “b”: Modulator fault status character 2.
Bit 6 = 1 always.
Bit 5 = AGC fault.
Bit 4 = Modulator RF synthesizer fault.
Bit 3 = Bit clock fault.
Bit 2 = Transmit clock fault.
Bit 1 = I channel fault.
Bit 0 = Q channel fault.
Where: Character “c”: Demodulator fault status character 1.
Bit 6 = 1 always.
Bit 5 = Demodulator fault.
Bit 4 = Carrier detect status (0 for decoder lock).
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of demodulator
stored faults.
Where: Character “d”: Demodulator fault status character 2.
Bit 6 = 1 always.
Bit 5 = Demodulator RF synthesizer fault.
Bit 4 = not used.
Bit 3 = I channel fault.
Bit 2 = Q channel fault.
Bit 1 = Bit clock fault.
Bit 0 = BER threshold fault.
Where: Character “e”: Common equipment fault status character 1.
Bit 6 = 1 always.
Bit 5 = M&C fault.
Bit 4 = Interface fault.
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of common
equipment stored faults.
B–70
Rev. 6
SDM-650B Satellite Modem
Remote Control Operation
Where: Character “f”: Common equipment fault status character 2.
Bit 6 = 1 always.
Bit 5 = Battery fault.
Bit 4 = +5V fault.
Bit 3 = +12V fault.
Bit 2 = -12V fault.
Bit 1 = not used.
Bit 0 = not used.
Where: Character “g”: Interface transmit side faults character 1.
Bit 6 = 1 always.
Bit 5 = not used.
Bit 4 = not used.
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of interface transmit
side stored faults.
Where: Character “h”: Interface transmit side faults character 2.
Bit 6 = 1 always.
Bit 5 = Transmit clock activity fault.
Bit 4 = Transmit synthesizer PLL fault.
Bit 3 = not used.
Bit 2 = not used.
Bit 1 = not used.
Bit 0 = not used.
Where: Character “i”: Interface receive side faults character 1.
Bit 6 = 1 always.
Bit 5 = MUX lock fault.
Bit 4 = Buffer clock activity fault.
Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of interface receive
side stored faults.
Where: Character “j”: Interface receive side faults character 2.
Bit 6 = 1 always.
Bit 5 = Receive synthesizer PLL fault.
Bit 4 = not used.
Bit 3 = not used.
Bit 2 = not used.
(See Note)
Bit 1 = Buffer overflow fault.
(See Note)
Bit 0 = Buffer underflow fault.
Note: Available with buffer support hardware only.
Rev. 6
B–71
Remote Control Operation
SDM-650B Satellite Modem
B.2.8.20 Change Status
This command indicates that a change has or has not occurred on either the BCS_ or the
BCSF_ response since the last BCS_ or BCSF_ poll.
Command:
Response:
<add/CS_”cr”
>add/CS_x”cr””lf”]
Where: x =
“@” = no change since last CS_ poll.
“A” = BCS_ response has changed since last CS_ poll.
“B” = BCSF_ response has changed since last CS_ poll.
“C” = Both responses have changed since last CS_ poll.
B.2.8.21 Equipment Type
This command returns the equipment type polled and the software version.
Command:
Response:
<add/ET_”cr”
>add/ET_SDM650_x.xxx”cr””lf”]
Where: x.xxx = M&C firmware version.
B.2.8.22 Bulk Consolidated Status AUPC
Command:
Response:
<add/BCSA_”cr”
>add/BCSA_p1,p2,p3, . . . pn”cr””lf”]
Where: “pn” is the last parameter returned.
Parameter 1 (p1): Local AUPC enable ON/OFF.
p1 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
Parameter 2 (p2): Nominal Power Value.
p2 = snn.n, where “snn.n” is the Nominal Power Value in dBm.
Parameter 3 (p3): Minimum Power Value.
p3 = snn.n, where “snn.n” is the Minimum Power Value in dBm.
Parameter 4 (p4): Maximum Power Value.
p4 = snn.n, where “snn.n” is the Maximum Power Value in dBm.
Parameter 5 (p5): Eb/N0 Target Set Point.
p5 = n.n, where “n.n” is the Eb/N0 Target Set Point in dB.
Parameter 6 (p6): Max. Tracking Rate.
p6 = n.n, where “n.n” is the Max. Tracking Rate in dB/Min.
Parameter 7 (p7): Local Carrier Loss.
p7 = n, where “n” is “0” to indicate HOLD, “1” to indicate NOMINAL, or “2” to indicate
MAXIMUM.
Parameter 8 (p8): Remote Carrier Loss.
p8 = n, where “n” is “0” to indicate HOLD, “1” to indicate NOMINAL, or “2” to indicate
MAXIMUM.
Parameter 9 (p9): Interface Substitution Pattern 2047 (ON/OFF).
p9 = n, where “n” is “0” to indicate OFF, or “1” to indicate ON.
B–72
Rev. 6
Appendix C.
FIELD COMPATIBILITY
EFData modems can be configured to be compatible with other modems in the field:
•
•
•
Fairchild
Comstream
Fairchild Aydin data rate
This appendix allows the user to configure and/or identify compatible modems.
C.1 SDM-650B Standard Modem
The standard modem has the following assembly hardware configuration:
SDM-650B Chassis
M&C Card
M&C Software
Standard
U7 FW/0713-13X
U8 FW/0713-13X
U9 FW/0714-5X
Modulator Card
Modulator Daughter Card
Demodulator Card
Demodulator Daughter Card
Decoder Card
Decoder Software U8
Rev. 6
AS/1099-1
AS/0356
Fast Acquisition
FW/0713-35X
FW/0713-35X
FW/0714-5X
AS/0773-1
AS/0930-1 — Variable Rate
AS/0715-1 — Fixed Rate
AS/0778-1
AS/0698-X — Fixed Rate
AS/0929-1 — Variable Rate
AS/0365-1
FW/0562-1
ASYNC Standard
FW/0713-27X
FW/0713-27X
FW/0714-5X
ASYNC with Fast Acq.
FW/0713-34X
FW/0713-34X
FW/0714-5X
C–1
Field Compatibility
SDM-650B Satellite Modem
C.2 SDM-650B Fairchild-Compatible Modem
To change the standard modem to a Fairchild-compatible modem, the following changes
must be made:
M&C Software
Modulator Card
Demodulator Daughter Card
U9 FW/0714-6X
AS/0773-3 (Resistor Pack Changes)
AS/0929-3 — Variable Rate
AS/0698-X FDC COMP — Fixed Rate
FW/0562-2
Decoder Software U8
C.3 SDM-650B Aydin Data Rate Modem
To change the Fairchild-compatible modem to an Aydin compatible data rate, additional
changes must be made to the Fairchild-compatible configuration:
Modulator Card
Decoder Card
AS/0773
AS/0365
12 (Aydin Data Rate, crystal = 4.117333 MHz)
4 (Aydin Data Rate, crystal = 4.117333 MHz)
C.4 SDM-650B Comstream Modem
To change the modem to a Comstream-compatible modem, the following changes must
be made:
M&C Software
Decoder Card Software
Interface Board
C–2
U9 FW/0714-9X
U8 FW/0562-3X
AS/0627-2
V.35 Interface with Engineering Waiver #212 Modifies
Carrier ON/OFF Control Using RTS (RS)
Rev. 6
Appendix D.
SOFTWARE CHANGE
INSTRUCTIONS
Steps 1 through 5 are instructions for changing software on the M&C card.
Steps 6 through 9 are instructions for changing software on the Viterbi decoder card. If
the Viterbi decoder software does not need to be changed, skip to Step 10 and continue.
To change the software:
1. Remove the M&C card (AS/0356) using the black card ejector on vertical card.
2. Remove the proms in location U7 and U9 (28 Pin — 0.6” wide).
3. Install the new firmware FW0713-XX into U7 position, and FW0714-XX into
U9 position, making sure that pin 1 is installed properly.
Note: See Table D-1 for the definition of the various firmware that is available.
4. Remove the battery jumper, JP6. Short out the leads on capacitor C12, and
re-install JP6 in the ON position.
5. Re-install the M&C card into the modem chassis.
6. Remove the Viterbi decoder card (AS/0701, AS/0949, or AS/2133) from the
modem chassis. The decoder card is the horizontal card with gray card ejectors.
7. Remove the prom in proper location on the Viterbi decoder (28 pin — 0.6” wide).
Refer to the decoder firmware in Table D-1 for location and description of the
various Viterbi decoder boards.
Rev. 5
D–1
Software Change Instructions
SDM-650B Satellite Modem
8. Install the new firmware FW/XXXX in UX position on the Viterbi decoder. See
Table D-1 for the definition of the various firmware that is available.
9. Re-install the decoder into the modem chassis.
10. Turn ON the power switch.
11. Go to the Utility menu on the front panel, and program the time, day, TXA, TXB,
TXC, TXD, RXA, RXB, RXC, and RXD to the new data/code rates.
Note: The data/code rate assignment in the Utility menu must match the filter
assignment on the daughter card. Each daughter card is labeled with the filter
assignment (A, B, C, and D) and associated symbol rate. Example: The label for
a 64 kbit/s, 7/8 rate, QPSK filter is 36.57.
12. Go to the Config menu on the front panel and select the desired TX and RX rates.
Turn ON the RF output.
The software change is complete.
The firmware for the M&C cards is contained in three EPROMs:
•
•
EPROMs U7 and U8 contain the various modem program codes.
EPROM U9 contains the data information for the various plug-in modules.
The firmware for the Viterbi decoder card is contained in one EPROM. Refer to Table D1 for the location.
Table D-1. EFData M&C Viterbi Decoder Firmware
M&C EEPROM#
U7
U7, U8
U7, U8
Firmware #
FW/0713-11D
FW/0713-19X
FW/0713-56X
U7, U8
FW/0713-57X
U9
Decoder EEPROM#
U1
U17
U42
FW/0714-7X
Firmware #
FW/0760-1X
FW/1910X
FW/2355X
Description
Variable Rate Standard (Version 2.66)
Variable Rate (Version 3.XX)
Variable Rate, Fast acquisition, Directed Sweep
(Version 4.XX)
Drop and Insert, Fast Acquisition, Directed Sweep
(Version 6.XX)
70/140 MHz
Description
AS/0701 Viterbi Decoder
AS/0949 Viterbi Decoder
AS/2133 Viterbi Decoder
Note: The “X” following each of the firmware numbers stands for the revision
release information of that firmware number.
D–2
Rev. 5
Appendix E.
AGC INTERFACE
The AGC interface option has been designed for external monitoring of the dynamic
range of a modem.
The AGC interface output will be 0V out for minimum modem power, and +10V out for
maximum modem power.
Rear panel gain and offset adjustments allow fine tuning of these voltages.
The AGC interface output is approximately linear, making it easy to determine the input
power to the modem.
The demodulator fault relay closure can be used as an indication of the validity of the
AGC voltage. If a fault is indicated, the AGC voltage is not valid.
Refer to Figure E-1 for a diagram of the rear panel showing the location of the AGC
connector.
Rev. 5
E–1
AGC Interface
SDM-650B Satellite Modem
DATA
GROUND
ERDE
I/OI
TX/IF
OUTPUT
CP1
REMOTE
J10
AGC
J6
J8
GAIN
J9
FAULT
MADE IN USA
J7
OFFSET
J11
RX/IF
INPUT
CP2
Figure E-1. Rear Panel View
E.1 Connector Pinouts
The AGC interface is supplied on a 9-pin female D connector that is accessible from the
rear panel. Screw locks are provided for mechanical security of the mating connector.
Function
GROUND
AGC OUTPUT
NO CONNECTION
Name
GND
AGC-OUT
NC
Pin #
9
1
2, 3, 4, 5, 6, 7, 8
E.2 Installation Instructions
Parts and assemblies may be damaged by Electrostatic Discharge (ESD).
ESD safety precautions should always be observed when handling parts.
CAUTION
E.2.1 Parts Required
Qty.
1
1
E–2
Part #
PC/0769
FP/1873
Description
AGC Interface
Back Panel for the AGC
Rev. 5
SDM-650B Satellite Modem
AGC Interface
E.2.2 Installation Procedure
Refer to Figure E-2 as needed. To install the AGC interface option:
1. Remove the rear panel of the modem.
2. Using the hardware provided, install the AS/0769 board to the modem
motherboard between CP1 and CP2 (IF OUT and IF IN). (Refer to Figure E-1.)
3. Attach the following wires to the motherboard:
a.
b.
c.
d.
E1
E2
E3
E4
⇒
⇒
⇒
⇒
GND
+12V
AGC J3, B4
-12V
Refer to Figure E-2.
4. Adjust R4 to achieve a reading of approximately 4.33KΩ between U1 pin 1 and
pin 2 (refer to Figure E-3).
5. Power up the modem.
6. Adjust R5 to achieve a reading of approximately +5.75V at the right side of R2.
7. Measure the voltage at pin 1 of the 9-pin connector:
a. To achieve the minimum AGC voltage output at pin 1, set the modem input
to -55 dBm and verify the reading is 0V.
b. To achieve the maximum AGC voltage output at pin 1, set the modem input
to -30 dBm and verify the reading is 10V.
If minor adjustments are necessary, adjust the GAIN and OFFSET
potentiometers until both readings are correct.
8. Install the new back panel (refer to Figure E-1).
Rev. 5
E–3
AGC Interface
SDM-650B Satellite Modem
Data
I/O
C1
C3
Gnd -5 +12 -12 +5
IF OUTPUT
J8
J5
J4
Remote
MOD J1
J6
AS/0769
AGC Interface
DECODER J2
C2
Fault
GND
CP1
E1 E2 E3 E4
J7
IF INPUT
DEMOD J3
J9
CP2
Gnd -5 +12 -12 +5
Mother Board
Wire Connections
8
1
C
B
A
B4
Figure E-2. Wiring Diagram
E–4
Rev. 5
SDM-650B Satellite Modem
AGC Interface
Figure E-3. AGC Adapter Board
Rev. 5
E–5
AGC Interface
SDM-650B Satellite Modem
This page is intentionally left blank.
E–6
Rev. 5
Appendix F.
ASYNCHRONOUS OVERHEAD
CHANNEL UNIT
This appendix provides information on operating the modem from the front panel with
the asynchronous overhead channel unit option installed. The following version is
described:
•
•
Firmware number:
Software version:
FW/0713-34L
4.12A
Notes:
1. The same version of firmware (listed above) is used for the asynchronous
overhead channel unit, whether or not the AUPC option is installed. However, if
the modem hardware does not support AUPC, the AUPC-related menus and
options (e.g., SELECT REMOTE; SELECT CONFIG, AUPC) will not be
displayed in the front panel menus.
2. The ASYNC breakout panel is required with the asynchronous overhead channel
unit. For information on the ASYNC breakout panel, refer to the ASYNC
Breakout Panel Installation and Operation Manual.
3. For remote control operation information on the modem with the asynchronous
overhead channel unit installed, refer to Appendix B.
This appendix includes:
•
•
•
•
•
Rev. 5
Functional description of ASYNC overhead channel unit
ASYNC interface connector pinouts
ASYNC interface specifications
Functional description of ASYNC overhead channel unit with AUPC
Front panel operation information
F–1
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.1 Functional Description of ASYNC Overhead Channel Unit
The ASYNC overhead interface module consists of three subassemblies:
•
•
•
Connector board (AS/1328)
Terrestrial interface (AS/1311)
Data processor board (AS/1289)
The connector board provides the physical interface utilizing a 50-pin D connector. The
terrestrial interface contains all circuitry required for G.703, RS-422, MIL-STD-188, and
V.35 type interfaces for synchronous data. The terrestrial interface also contains circuitry
for RS-232-C and RS-485 type interfaces for ASYNC data.
The data processor contains all circuitry required for:
•
•
•
Multiplexing the synchronous and ASYNC data streams
Data rate synthesizers
Optional plesiochronous buffer
Refer to Figure F-1 for a block diagram of the ASYNC overhead interface.
F–2
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
RECEIVE SECTION
TRANSMIT SECTION
ES TO ES ASYNC
FRAMING/
TIMING
LOGIC (MUX)
RS-232
INTERFACE
P/O
INT
LPBK
MODEM
P/O
INT
LPBK
DEFRAME/TIMING
LOGIC (DEMUX)
RS-232
INTERFACE
ES TO ES
ASYNC
TX DEJITTER
G.703
CLK
DATA
CLK
T1/E1 INTERFACE
T2/E2
PLESIOCHRONOUS
BUFFER
P/O
BASE
BAND
LPBK
P/O
BASE
BAND
LPBK
RS-422 INTERFACE
MIL-STD-188-114
T1/E1
T2/E2
G.703
INTERFACE
RS-422
INTERFACE
MIL-STD
188-114
V.35
INTERFACE
CLK
DATA
CLK
DATA
V.35 INTERFACE
DATA
SATELLITE CLOCK
EXTERNAL REFERENCE CLOCK
(TRANSMIT TERR CLOCK)
INTERNAL CLOCK
CLOCK
SYNTHESIS
INTERNAL CLOCK
TRANSMIT TERR CLOCK
EXTERNAL REFERENCE CLOCK
CLOCK SYNTHESIS
Figure F-1. Asynchronous Overhead Interface Block Diagram
Rev. 5
F–3
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.1.1 Terrestrial Interface
The terrestrial interface (AS/1311) forms the top, when mated with the connector board,
of the 2-board module. The terrestrial interface contains all balanced pair drivers and
receivers for:
•
•
•
RS-422
MIL-STD-188
V.35
Data inputs are send data (SD) and transmit clock (TT or SCTE).
Data outputs are modem reference clock (SCT or ST), receive data (RD), and receive
clock (RT or SCR).
The “handshake” ASYNC signals are:
•
•
•
•
•
•
Request to Send (RTS)
Clear to Send (CTS)
Data Mode
Data Set Ready
Receiver Ready
Receive Line Signal Select
This board may otherwise contain circuitry for transformer balanced data interfaces
supporting CCITT G.703 parameters.
Data inputs are Send Data (SD), and outputs are Receive Data (RD).
Data rates of 1.544, 2.048, 6.312, and 8.448 bits/s are supported.
Line codes for zero substitution are B6ZS, B8ZS, AMI, and HDB3. The configuration of
this section is determined at the factory, and is not user selectable in the field.
The ASYNC data channel has three interface options:
•
•
•
RS-232-C electrical interface allows full-duplex operation.
RS-485 4-wire also allows full-duplex operation.
RS-485 2-wire allows half-duplex operation.
These options are jumper selectable. Refer to Figure F-2 for jumper locations on the
interface board. Refer to Tables F-1 and F-2 for jumper configuration information for the
various options and data rates.
F–4
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
1
1
JP11
2
AS/1311 REV
ASYNC OVERHEAD TERRESTRIAL INTERFACE BOARD
JP1
1
JP4
JP5
JP6
JP7
1
1
1
JP8
1
JP13
1
1
1
JP12
JP9
JP2
2
1
2
JP3
1
JP10
1
Figure F-2. Asynchronous Overhead Interface Board
Table F-1. Asynchronous Overhead Jumpers
JP #
JP1
JP2
JP3
JP10
JP11
JP12
JP8, JP9, JP13
Pin #
Function
1 to 3, and 2 to 4
V.35, RS-422, MIL-STD-188
3 to 5, and 4 to 6
G.703
Auto TX CLK Phase Select
1 to 2
Fixed Phase, Normal
3 to 4
Fixed Phase, Inverted
5 to 6
1 to 2
G.703 data activity detect
2 to 3
TX Terr CLK activity detect
1 to 2
V.35 operation
2 to 3
RS-422, MIL-STD-188 operation
1 to 2
Normal SCT output
3 to 4
TX CLK “chained” to SCT output
1 to 2
2-wire operation
2 to 3
4-wire operation
Asynchronous
1 to 2
RS-485
2 to 3
RS-232-C
Table F-2. Data Rate Jumpers
Data Rate
1.544 Mbit/s
2.048 Mbit/s
2.048 Mbit/s
6.312 Mbit/s
6.312 Mbit/s
8.448 Mbit/s
Rev. 5
Impedance
BAL−100
BAL−120
UNBAL−75
BAL−110
UNBAL−75
UNBAL−75
JP4
OFF
OFF
OFF
1 to 2
OFF
OFF
JP5
ON
ON
ON
OFF
OFF
ON
JP6
ON
ON
ON
OFF
OFF
ON
JP7
OFF
OFF
OFF
OFF
OFF
OFF
Voltage
5.8 Vp-p
5.8 Vp-p
4.6 Vp-p
1.8 Vp-p
3.3 Vp-p
4.8 Vp-p
F–5
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.1.2 Multiplexer
The data processor (AS/1289) forms the bottom of the 2-board module. This board
contains the data multiplexer and demultiplexer.
The synchronous data stream is multiplexed with a 1/15 overhead channel, and the
resultant information is interfaced to the modulator/coder section of the modem.
The input clock is normally the recovered clock from the terrestrial interface board
(SCTE), but the modem reference clock can be used by selecting the internal clock.
The 1/15 overhead channel is composed of:
•
•
•
•
Framing signals
Flags
Spare bit positions
ASYNC data stream
The maximum ASYNC data rate is limited to 1.875% of the synchronous data rate.
F.1.3 Demultiplexer
Receive data and clock from the demodulator/decoder are input to the DEMUX. The
DEMUX synchronizes to the frame pattern, and separates the synchronous and ASYNC
data. Synchronization is indicated by the demux lock LED on the front edge of the board.
The synchronous data is dejittered, and interfaced either to the optional plesiochronous
buffer or to the terrestrial interface board.
F–6
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.1.4 Plesiochronous Buffer
Where the option is installed, data from the DEMUX section is fed into a plesiochronous
buffer. The buffer size is selectable in increments of 1, 2, 4, 6, 8, 12, 24, and 32 ms. The
buffer is automatically centered on resumption of service after an outage. The buffer can
also be commanded to center from the Config Interface menu of the front panel, or
remotely.
The start-up buffer will overfill upon centering, to match the satellite frame to the
terrestrial frame, with a maximum slide of 0.5 ms. For obvious reasons, manual centering
will generally not be plesiochronous.
The fill status is available as a monitor function, and is accurate to 1%. Overflow or
underflow incidents will be momentarily indicated by red LEDs on the module, and are
stored in the “StFaults” section of the M&C status registers, along with the date and time
of the incident. These are stored in battery-backed RAM.
To synchronize the receive data output with the satellite data, the user will normally
select Receive Clock. The data will then be clocked out of the buffer by the clock
recovered from the receive data input. The user may select from two other clock sources
as a backup:
•
•
User-supplied external reference clock
Internal clock source
Problems on either the recovered receive data input clock or the external clock (if
selected) will cause satellite clock to be substituted, and a fault will be signaled.
Rev. 5
F–7
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.2 ASYNC Interface Connector Pinouts
The ASYNC interface is provided on a 50-pin female D connector accessible from the
rear panel of the modem. Screw locks are provided for mechanical security of the mating
connector.
Signal Function
GROUND
T1E1 SEND DATA A
T1E1 SEND DATA B
EXTERNAL CLOCK A
EXTERNAL CLOCK B
T1E1 RECEIVE DATA A
T1E1 RECEIVE DATA B
TX DATA B (ASYNC)
SEND DATA A
SCT SIGNAL A
TX DATA A (ASYNC)
SEND DATA B
SCT SIGNAL B
RX DATA B (ASYNC)
RECEIVE DATA A
RECEIVE CLOCK A
RX DATA A (ASYNC)
RECEIVE DATA B
RECEIVE CLOCK B
TRANSMIT TIMING A
REQUEST TO SEND A
REQUEST TO SEND B
TRANSMIT TIMING B
RECEIVER READY A
RECEIVER READY B
RS422 TX DATA A
CLEAR TO SEND B
DATA SET READY A
DATA SET READY B
CTS A
F–8
Name
GND
T1E1-SDA
T1E1-SDB
EXCA
EXCB
T1E1-RDA
T1E1-RDB
TXD-B
SDA
SCT/STA
TXD-A
SDB
SCT/STB
RXD-B
RDA
SCR/RTA
RXD-A
RD-B
SCR/RTB
SCTE/TTA
RTSA
RTSB
SCTE/TTB
RLSD/RRA
RRB
R422TXDA
CTSB
DSR/DMA
DMB
CTSA
Pin #
1, 2
34
18
35
19
36
20
4
37
21
5
38
22
6
39
23
7
40
24
12
45
29
13
46
30
14
31
48
32
47
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.3 ASYNC Interface Specifications
Main Channel
MIL-STD-188-144
RS-422/-449
V.35
G.703
Data Rates
9.6K, 19.2K, 32 k/bits to 8.448 Mbit/s, in 32 k/bits steps
G.703 Data Rates
1.544 Mbit/s
Jumper Selectable
2.048 Mbit/s
6.312 Mbit/s
8.448 Mbit/s
G.703 Line Code
AMI, B8ZS, B6ZS, HDB3
Transmit Clock Reference
Internal modem reference or external transmit clock (SCT or
TT)
Jitter Attenuation
Per G.703
Pulse Mask
Per G.703
Overhead Channel
Overhead Rate
16/15 of main channel
ASYNC Channel Rate (max.)
< 1.875% of main channel
ASYNC Channel Interface
RS-232-C
2-wire RS-485 half-duplex
4-wire RS-485 full-duplex
Connector
25-pin D on breakout panel
Baud Rates, Asynchronous
110, 150, 300, 600, 1200, 2400, 4800, 9600, 19200,
38400 bit/s
Asynchronous Format
5, 6, 7, or 8 data bits
Even, Odd, or no parity
1 or 2 stop bits (1 or 1.5 for 5 bit)
Pleisiochronous Buffer Specifications
Buffer Size
384 to 262144 bits, in 16-bit steps
Buffer Fill Status
Monitored accurate to ± 1%
Buffer Centering
Automatic or Manual
Buffer Clock Reference
Transmit
Internal (10-5 Stability)
External
Receive (Buffer Bypass)
External Clock Amplitude
Differential, 0.5 to 5 Vp-p
Common Mode, 0 to 5 VDC
External Clock Frequency
256 to 2048 kHz, in 64 kHz steps
External Clock Impedance
100Ω
External Clock Input Type
Sine or square wave
50%, ± 10%
Physical Interface
Factory Option
Rev. 5
F–9
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.4 Functional Description of ASYNC Overhead Channel Unit with AUPC
The ASYNC overhead channel unit with the AUPC option functions very much the same
as the original ASYNC overhead channel unit, except for some added features.
The connector pinouts and specifications apply to both versions of the ASYNC overhead
channel unit.
There are two added features in the AUPC version:
•
•
Automatic Uplink Power Control
Modem-to-Modem Channel for Remote M&C
These features are outlined in the following sections.
F.4.1 AUPC
This feature is designed for remote communication between a local modem (A) and a
remote modem (B). This feature allows the local modem to maintain a constant
(± 0.5 dB) Eb/N0 by requesting changes in transmit power level from the remote modem.
The user has the ability to set the following parameters:
•
•
•
•
•
•
•
•
AUPC Enable (turns the AUPC ON or OFF)
Remote Carrier Loss Action (Nominal, Maximum, Hold)
Carrier Loss Action (Nominal, Maximum, Hold)
Set Nominal Power Limit
Set Maximum Power Limit
Set Minimum Power Limit
Set Target Eb/N0
Set Maximum Tracking Rate
When AUPC is turned ON in the local modem, it allows commands from the remote end
to increment or decrement the power in 0.5 dB steps. This feature also allows power to be
changed for remote or local carrier loss.
When AUPC is turned OFF in the local modem, the commands are still sent, but the local
modem will not respond to the commands.
F–10
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
The action at loss of lock is as follows (modem A loses carrier detect):
1. Modem A sets its power to Nominal, Hold, or Maximum, as specified by Carrier
Loss action.
2. Modem A sends Carrier Lost command to modem B.
3. Modem B sets its power to Nominal, Hold, or Maximum, as specified by Remote
Carrier Loss action.
Note: Local Carrier Loss has priority over Remote Carrier Loss.
F.4.2 Modem-to-Modem Channel for Remote M&C
This feature allows the user to monitor and control a remote modem location using the
front panel or serial port of the local modem.
The user has the ability to set or reset the following commands:
•
•
•
Baseband Loopback
TX 2047 Pattern
AUPC Enable
The user has the ability to remotely monitor the Receive 2047 BER.
Rev. 5
F–11
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.5 Front Panel Operation
Note: The same version of firmware (FW/0713-34L, 4.12A) is used for the asynchronous
overhead channel unit, whether or not the AUPC option is installed. However, if the
modem hardware does not support AUPC, the AUPC-related menus and options (e.g.,
SELECT REMOTE; SELECT CONFIG, AUPC) will not be displayed in the front panel
menus.
The modem front panel control uses a tree-structured menu system (Tables F-3 through
F-12) to access and execute all functions.
The main level of the menu system is the Select menu, which may be accessed from the
base level by pressing any of the arrow keys. From the Select menu, any one of six
functional categories can be chosen:
•
•
•
•
•
•
Configuration
Monitor
Faults
Stored faults (StFaults)
Remote
Utility
Note: For general information on front panel operation, refer to Chapter 4.
F–12
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.5.1 Menus and Options Overview
Refer to Section F.5.2 for menu and option explanations.
Note: The “A” after the software version designates “Asynchronous.”
Table F-3. Main Front Panel Menu with Asynchronous Overhead (with AUPC)
Screen
SDM650 “TYPE”
SW_4.12A
SELECT CONFIG
Submenus/Options
MOD
DEMOD
INTRFACE
AUPC
SELECT MONITOR
Comments
This is an information-only screen.
The “A” on line 2 means the
asynchronous option is installed.
Go to Table F-4.
Go to Table F-5.
Go to Table F-6.
Go to Table F-7.
Go to Table F-8.
SELECT FAULTS
Go to Table F-9.
SELECT StFAULTS
Go to Table F-10.
SELECT REMOTE
Go to Table F-11.
SELECT UTILITY
Go to Table F-12.
Table F-4. Select Configuration Modulator Menu (with AUPC)
Menus
TX-x Code_Rate
Submenus/Options
x = A, B, C, D, or V
TX_Freq
50.000 to 90.000 MHz or 100.000 to
180.000 MHz
ON
OFF
-5.0 dBm to -30 dBm
RF_Out
TX_Power
or
AUPC_PWR
DifEncdr
Scramblr
CW_Mode
Rev. 5
Comments
In 2.5 kHz steps.
In 0.5 dBm steps.
When AUPC is turned ON in the
AUPC configuration menu, this
window will display AUPC_PWR.
ON
OFF
ON
OFF
Center
Dual
Offset
F–13
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
Table F-5. Select Configuration Demodulator Menu (with AUPC)
Menus
RX-x Code_Rate
Submenus/Options
x = A, B, C, D, or V
RX_Freq
In 2.5 kHz steps.
SWP_RACQ
50.000 to 90.000 MHz, or
100.000 to 180.000 MHz
ON
OFF
ON
OFF
ON
OFF
0 to 999 sec
SWP_CNTR
0 to 50000 Hz
SWP_RNGE
-25000 to +25000 Hz
SWP_DIR
FORWARD
REVERSE
1E-3
1E-4
1E-5
1E-6
1E-7
1E-8
NONE
Appear only when fast acquisition is
turned ON.
Appear only when fast acquisition is
turned ON.
Appear only when fast acquisition is
turned ON.
Dscrmblr
IFLoopBk
RFLoopBk
BERT_set
F–14
Comments
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
Table F-6. Select Configuration Interface Menu (with AUPC)
Menus
TX_clock
Buf_clk
RX_clock
EXT_REF
BBLoopBk
INTF_LBk
TX CODE
RX CODE
TX 2047
BUF_SIZE
BUF_CNTR
TX BAUD
RX BAUD
Rev. 5
Submenus/Options
External
Internal
Satellite
Internal
Ext_Ref
External
Normal
Inverted
Typical:
1.544 MHz
5 MHz
10 MHz
ON
OFF
ON
OFF
AMI
B8ZS
B6ZS
HDB3
AMI
B8ZS
B6ZS
HDB3
ON
OFF
BITS = 32 to 262144, in 16 bit steps, or
MILLI-SECONDS = 6 ms to 96 ms, in 1 ms
steps
YES/NO
110
150
300
600
1200
2400
4800
9600
19200
38400
110
150
300
600
1200
2400
4800
9600
19200
38400
Comments
AUPC option only.
In bits per second.
In bits per second.
F–15
Asynchronous Overhead Channel Unit
CH LENTH
SDM-650B Satellite Modem
5 bits
6 bits
7 bits
8 bits
1 bit
2 bits
EVEN
ODD
NONE
STOP BIT
PARITY
Table F-7. Select Configuration AUPC Menu (with AUPC)
Menus
NOM PWR
Submenus/Options
ON
OFF
-30 to -5 dBm
MIN PWR
-30 to -5 dBm
MAX PWR
-30 to -5 dBm
Eb/N0 SP
3.2 to 9.7 dB, in 0.1 dB steps
MAX TR
0.5 to 6 dBm/minutes
LOCAL CL
MAXIMUM
NOMINAL
HOLD
MAXIMUM
NOMINAL
HOLD
AUPC
REMOTECL
Comments
Table F-8. Select Monitor Menu (with AUPC)
Menus
Raw_BER
Submenus/Options
Range: < 1.0E-4 to 2550E-4
Corr_BER
Range: < 1E-8 to > 1E-3
Eb/N0
Range: < 3.2 to > 9.7 dB
SWP FREQ
Range: -30000 to +30000 Hz
Fil_Stat
Range: 1% to 99%
RXSignal
Range: < -60 to > -30 dBm
RX 2047
Range: < 1.0E-3 to > 1E-6, or No
Data
Comments
Displays information when fast
acquisition has been turned ON in the
Utility menu.
Note: Data is not available or displayed when the decoder loses lock.
F–16
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
Table F-9. Select Faults Menu (with AUPC)
Menus
Mod Flts
––––––
–
Dmd Flts
+–++++––
CEq Flts
––––
–
TX_INTF
––
RX_INTF
––
+–+
Rev. 5
Submenus/Options
RF_Syn
Data_Clk
TClk_Syn
I-Channl
Q-Channl
AGC levl
Module
C_Detect
RF_Syn
Data Clk
I-Channl
Q-Channl
Dscrambl
BERthrsh
Module
Battery
-12 volt
+12 volt
+5 volt
Intrface
TX_PLL
Clk_Act
BUF_UNFL
BUF_OVFL
RX_PLL
Buff_Clk
MUX_lock
Comments
F–17
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
Table F-10. Select Stored Faults (StFaults) Menu (with AUPC)
Menus
Mod Fltx
MM/DD/YY
HH/MM/SS
Dmd Fltx
MM/DD/YY
HH/MM/SS
CEQ Fltx
MM/DD/YY
HH/MM/SS
TX_INTFx
Submenus/Options
RF_Syn
Data_Clk
TClk_Syn
I-Channl
Q-Channl
AGC_levl
Module
C_Detect
RF_Syn
Data_Clk
I-Channl
Q-Channl
Dscrambl
BERthrsh
Module
Battery
-12 volt
+12 volt
+5 volt
Controlr
Intrface
TX_PLL
Clk_Act
Comments
Mod Flt0 through Mod Flt9.
BUF_UNFL
BUF_OVFL
RX_PLL
Buff_Clk
MUX_lock
YES/NO
RX_INTF0 through RX_INTF9.
Dmd Flt0 through Dmd Flt9.
CEQ Flt0 through CEQ Flt9.
TX_INTF0 through TX_INTF9.
MM/DD/YY
HH/MM/SS
RX_INTFx
MM/DD/YY
HH/MM/SS
CLEAR ??
StFaults
Table F-11. Select Remote Menu (with AUPC)
Menus
REMOTE CONFIG
REMOTE MONITOR
F–18
Submenus/Options
AUPC
ON
OFF
BBLoopBK
ON
OFF
TX 2047
ON
OFF
RX 2047
BER (1E-X)
NO DATA
Comments
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
Table F-12. Select Utility Menu (with AUPC)
Menus
Time
Date
Submenus/Options
SS
HH:MM AM/PM
MM/DD/YY
LAMP TEST?
YES
Add: 1
xxxxyyyy
Address = 1 to 255
Parity:
Even
Odd
Baud Rate = 110 to 9600
+20 to -20.0 dB
POW ADJ
OP MODE
FAST ACQ
INT_TYPE
FILTERS ADJUST
TX only
RX only
DUPLEX
ON
OFF
RS422
V.35
MOD ADJ.
DEMOD ADJ.
Assign TX_Fltrs
Filters = A, B, C, D, or V
Assign RX_Fltrs
Filters = A, B, C, D, or V
Rev. 5
Comments
Seconds (SS). Reset at [ENTER].
Status only.
This is a factory setting and should
not be changed by unauthorized
persons.
F–19
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.5.2 Menu Explanations
F.5.2.1 Select Configuration
Refer to Table F-3.
Modem configuration may be viewed or changed by entering the Config menu from the
Select menu on the front panel. After entering the Config menu, use [←] and [→] to select
one of the following configurations:
•
•
•
•
MOD
DEMOD
INTERFACE
AUPC
Enter the selected Config menu by pressing [ENTER]. Use [←] and [→] to view the
selected configuration parameters. Press [ENTER] to begin the configuration process.
Then, use the arrow keys to make the changes.
After the changes are made and the display represents the correct parameters, execute the
change by pressing [ENTER]. When [ENTER] is pressed, the necessary programming is
initiated by the modem. Press [CLEAR] to interrupt the process.
The following sections describe each configuration function in detail.
F–20
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.5.2.1.1 Configuration Modulator
Refer to Table F-4.
TX-x
TX_Freq
Transmitter Rate Selection. Select one of four pre-defined transmitter
coder/data rate combinations or a variable rate selection.
On entry, the current transmitter rate is displayed with the flashing cursor
on the first character of the code rate on line 1. The data rate is displayed
on line 2. Use the arrow keys to select one of four pre-defined rates.
Filters that are not present may display N/A (not assigned). They cannot
be programmed. If the modem is equipped with the variable rate option,
TXV can also be selected. Enter the desired data rate.
Programs the modulator transmit frequency between 50 and 90 MHz, or
100 and 180 MHz, in 2.5 kHz steps.
On entry, the current transmitter frequency is displayed with the flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment or decrement the digit at the flashing
cursor. Press [ENTER] to execute the change.
RF_Out
TX_Power
Note: The transmitter frequency is programmable within the specified
range (50 to 90 MHz, or 100 to 180 MHz), in 2.5 kHz steps. When the
transmitter frequency is changed, the transmitter is automatically turned
OFF to prevent the possible swamping of other channels. Use the
RF_Out function to turn the transmitter ON.
Programs the modulator output to ON or OFF.
On entry, the current status of the output is displayed with the flashing
cursor on the first character. Use the arrow keys to select ON or OFF.
Press [ENTER] to execute the change.
Programs the modulator output power level from -5 dB to -30 dBm, in 0.5
dB steps.
On entry, the current transmitter power level is displayed with the flashing
cursor on the first character. [↑] and [↓] are used to increase or decrease
the output power level in 0.5 dBm steps. Press [ENTER] to execute the
change.
AUPC_PWR
AUPC status window.
DifEncdr
When AUPC is turned ON in the AUPC Config menu, this window
replaces the TX_POWER window. This is a monitor point only, and
cannot be programmed from this menu.
Programs the differential encoder ON or OFF.
Scramblr
On entry, the current status of the DifEncdr is displayed with the flashing
cursor on the first character. Use the arrow keys to select ON or OFF.
Press [ENTER] to execute the change.
Programs the modulator for scrambler ON or OFF.
On entry, the current status of the scrambler is displayed with the
flashing cursor on the first character. Use the arrow keys to select ON or
OFF. Press [ENTER] to execute the change.
Rev. 5
F–21
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
CW_Mode
Programs the modem for continuous wave mode.
(Test Mode Configuration
Option)
Three modes of operation are available:
•
•
•
Center
Dual
Offset
Center Mode:
Generates a carrier at the current modulator frequency. This can be
used to measure the output frequency.
Dual Mode:
Generates a dual side-band suppressed carrier signal. Side-bands
are at one-half the symbol rate from the carrier. This is used to
check the channel balance and carrier null.
Offset Mode:
Generates a single upper side-band suppressed carrier signal. The
upper side-band is at one-quarter the symbol rate from the carrier.
This is used to check the quadrature.
On entry, the Center mode is displayed. To activate this test mode, press
[ENTER]. Use the arrow keys to select the Dual or Offset modes. Press
[CLEAR] to return to the Config menu.
Note: When [CLEAR] is pressed, the modem is configured to the state it
was in before CW_Mode was invoked. The transmitter is automatically
turned OFF to prevent the possible swamping of other channels. Use the
RF_Out function to turn the transmitter ON.
F–22
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.5.2.1.2 Configuration Demodulator
Refer to Table F-5.
RX-x
RX_Freq
Receiver Rate Selection. Select one of four pre-defined receiver
decoder/data rate combinations or a variable rate selection.
On entry, the current receiver rate is displayed with the flashing cursor
on the first character of the code rate on line 1. The data rate is
displayed on line 2. Use the arrow keys to select one of four pre-defined
rates. Filters that are not present may display N/A (not assigned). They
cannot be programmed. If the modem is equipped with the variable rate
option, TXV can also be selected. Enter the desired data rate.
Programs the demodulator receive frequency between 50 and 90 MHz,
or 100 and 180 MHz, in 2.5 kHz steps.
Dscrmblr
On entry, the current receive frequency is displayed with the flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment or decrement the digit at the
flashing cursor. Press [ENTER] to execute the change.
Programs the demodulator/decoder for descrambler ON or OFF.
IFLoopBk
On entry, the current status of the descrambler is displayed with the
flashing cursor on the first character. Use the arrow keys to select ON
or OFF. Press [ENTER] to execute the change.
Programs the modem for IF loopback operation.
(Test Mode Configuration
Option)
RFLoopBk
(Test Mode Configuration
Option)
When the IF loopback is turned ON, the demodulator input is connected
to the modulator output through an internal attenuator. The demodulator
is programmed to the same frequency as the modulator. An attenuator
within the modem connects the IF Out to the IF In. When IF loopback is
turned OFF, the demodulator is tuned to its previous frequency, and is
reconnected to the IF input.
On entry, the current status of the IF loopback is displayed with a
flashing cursor on the first character. Use the arrow keys to select ON
or OFF. Press [ENTER] to execute the change.
Programs the modem for RF loopback operation.
When RF loopback is turned ON, the demodulator is programmed to
the same frequency as the modulator. When RF loopback is turned
OFF, the demodulator is tuned to its previous frequency.
On entry, the current status of the RF loopback is displayed with the
flashing cursor on the first character. Use the arrow keys to select ON
or OFF. Press [ENTER] to execute the change.
Rev. 5
F–23
Asynchronous Overhead Channel Unit
SWP_RACQ
SDM-650B Satellite Modem
Sets the sweep reacquisition rate from 0 to 999 seconds.
The time selected with this parameter is the time that the modem will
remain in a narrow sweep (± 10%) after acquisition has been
accomplished. After this timer runs out, the modem will return to the
normal sweep.
SWP_CNTR
On entry, the current programmed setting is displayed with a flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment and decrement the digit at the
flashing cursor. Select the number of seconds for the reacquisition
mode from 0 to 999 seconds. Press [ENTER] to execute the change.
Note: This window is only displayed when Fast Acquisition has been
turned ON in the Utility menu.
Programs the sweep center frequency for the directed sweep function.
The sweep center frequency may be set in the range from +25000 to 25000 Hz.
SWP_RNGE
On entry, the current programmed setting is displayed with the flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment and decrement the digit at the
flashing cursor. Select the sweep center frequency from -25000 to
+25000 Hz. Press [ENTER] to execute the change. When in directed
sweep, the value from the sweep monitor screen (when the modem was
last locked) should be entered for the sweep center frequency.
Note: This window is only displayed when Fast Acquisition has been
turned ON in the Utility menu.
Programs the overall travel of the sweep width range during acquisition
in the directed sweep mode. The sweep width may be set from 0 to
50000 Hz. (When set at 50000 Hz, the modem is in the fast acquisition
mode.)
On entry, the current programmed setting is displayed with a flashing
cursor on the first character. Use [←] and [→] to move the flashing
cursor. Use [↑] and [↓] to increment and decrement the digit at the
flashing cursor. Select a sweep range from 0 to 50000 Hz. Press
[ENTER] to execute the change.
SWP_DIR
When in directed sweep, the smaller the range, the faster the modem
will lock, provided the sweep center frequency is close.
Note: This window is only displayed when Fast Acquisition has been
turned ON in the Utility menu.
Programs the direction of the sweep travel in the directed sweep mode.
On entry, the current programmed setting is displayed with the flashing
cursor on the first character. Use the arrow keys to select Forward (+) or
Reverse (-). Press [ENTER] to execute the change.
F–24
Rev. 5
SDM-650B Satellite Modem
BERT_set
Asynchronous Overhead Channel Unit
This function is used to set the BER threshold. If the BER threshold set
is exceeded, a receive fault will be indicated by the modem status
indicators. BER threshold may be set from 1E-3 to 1E-8, or may be
disabled by specifying None.
On entry, the current setting of the BER threshold is displayed. Use [↑]
and [↓] to select the desired setting. Press [ENTER] to execute the
change.
F.5.2.1.3 Configuration Interface
Refer to Table F-6.
TX_Clock
Programs the modem for internal or external transmitter clock.
Buf_clk
On entry, the current status of the transmit clock is displayed with the
flashing cursor on the first character. Use the arrow keys to select
internal or external transmit clock. Press [ENTER] to execute the
change.
Programs the interface plesiochronous buffer output clock.
External sets this clock source to the external reference clock. When
External is selected and there is no clock present at the rear of the
modem, the clock will fall back to the satellite clock.
Satellite sets the output buffer clock to the satellite clock. This is also
the fallback clock. If satellite is selected, the Doppler shift caused by the
satellite will not be removed.
Internal sets the buffer clock to operate from the modem internal clock.
When EXT_REF clock is selected and there is no clock present, a fault
will occur. The output buffer clock will not fall back to satellite clock.
RX_clock
On entry, the current output buffer clock is displayed with the flashing
cursor on the first character. Use the arrow keys to select the desired
clock source. Press [ENTER] to execute the change.
Programs the modem for inverted or normal receiver clock.
EXT_REF
On entry, the current status of the receive clock is displayed with the
flashing cursor on the first character. Use the arrow keys to select
inverted or normal receive clock. Press [ENTER] to execute the change.
Programs the data rate of the external reference clock.
Typically, this clock source is programmed to 1.544, 5, or 10 MHz.
On entry, the current setting for the external reference is displayed with
the flashing cursor on the first character. Use [←] and [→] to move the
flashing cursor. Use [↑] and [↓] to increment or decrement the digit at
the flashing cursor. Press [ENTER] to execute the change.
Rev. 5
F–25
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
BBLoopBk
Programs the modem for baseband loopback operation.
(Test Mode Configuration
Option)
When baseband loopback is turned ON, baseband terrestrial data is
looped back on the customer side of the interface.
Note: Asynchronous data is not looped back in the baseband loopback
operation.
INTF_LBk
(Test Mode Configuration
Option)
On entry, the current status is displayed with the flashing cursor on the
first character. Use the arrow keys to select ON or OFF. Press [ENTER]
to execute the change.
Programs the modem for interface loopback operation. When interface
loopback is turned ON, data is looped back on the modem side of the
interface.
On entry, the current status is displayed with the flashing cursor on the
first character. Use the arrow keys to select ON or OFF. Press [ENTER]
to execute the change.
TX CODE
Note: Interface loopback only works when the TX data rate matches the
RX data rate.
Programs the transmitter for AMI, B8ZS, B6ZS, or HDB3 data.
RX CODE
On entry, the current coding format is displayed. Use the arrow keys to
select the desired coding format. Press [ENTER] to execute the
change.
Programs the receiver for AMI, B8ZS, B6ZS, or HDB3 data.
TX 2047
On entry, the current coding format is displayed. Use the arrow keys to
select the desired coding format. Press [ENTER] to execute the
change.
Programs the TX 2047 pattern ON or OFF.
This test mode is only available when AUPC is turned ON in the Utility
menu.
BUF_SIZE
On entry, the current status is displayed with the flashing cursor on the
first character. Use the arrow keys to select ON or OFF. Press [ENTER]
to execute the change.
This configuration function is used to set the size of the buffer.
BUF_CNTR
On entry, the current buffer length is displayed. Use [↑] and [↓] to select
the desired buffer size. The buffer size will be displayed in ms or bits.
Enter the Utility menu to change the buffer units to milli-seconds or bits.
32 to 262144 bits, in increments of 16, can be selected. If ms is
selected, 6 to 96 ms, in increments of 1 ms, can be selected. Press
[ENTER] to execute the change.
This configuration function is used to center the buffer.
TX BAUD
Press [ENTER] twice to center the plesiochronous buffer.
Programs the transmitter baud rate.
On entry, the current transmitter baud rate is displayed with the flashing
cursor on the first character. Use [↑] and [↓] to select the desired rate.
The baud rate may be programmed from 110 to 38,400 bit/s. Press
[ENTER] to execute the change.
F–26
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
RX BAUD
Programs the receiver baud rate.
CH LENTH
On entry, the current receiver baud rate is displayed with the flashing
cursor on the first character. Use [↑] and [↓] to select the desired rate.
The baud rate may be programmed from 110 to 38,400 bit/s. Press
[ENTER] to execute the change.
Programs the character length for the ASYNC format.
Stop BIT
On entry, the current character length is displayed with the flashing
cursor on the first character. Use [↑] and [↓] to select 5, 6, 7, or 8 bits.
Press [ENTER] to execute the change.
Programs the number of stop bits to 1 or 2.
PARITY
On entry, the current status of the stop bits is displayed with the flashing
cursor on the first character. Use [↑] and [↓] to select 1 or 2 stop bits.
Press [ENTER] to execute the change.
Programs the parity check to even, odd, or none.
On entry, the current status of the parity check is displayed with the
flashing cursor on the first character. Use the arrow keys to select Even,
Odd, or None. Press [ENTER] to execute the change.
Rev. 5
F–27
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.5.2.1.4 Configuration AUPC
Refer to Table F-7.
AUPC
Programs the AUPC ON or OFF.
NOM PWR
On entry, the current status is displayed with the flashing cursor on the first
character. Use the arrow keys to select ON or OFF. Press [ENTER] to
execute the change.
Programs the nominal power value of the AUPC.
MIN PWR
On entry, the current nominal power value is displayed with the flashing
cursor on the first character. Use the arrow keys to increment or decrement
the digit at the flashing cursor. The nominal power value can range from -30
to -5 dBm. Press [ENTER] to execute the change.
Programs the minimum power level of the AUPC.
MAX PWR
On entry, the current minimum power level is displayed with the flashing
cursor on the first character. Use the arrow keys to increment or decrement
the digit at the flashing cursor. The minimum power level can range from -30
to -5 dBm. Press [ENTER] to execute the change.
Programs the maximum power level of the AUPC.
Eb/N0 SP
On entry, the current maximum power level is displayed with the flashing
cursor on the first character. Use the arrow keys to increment or decrement
the digit at the flashing cursor. The maximum power level can range from 30 to -5 dBm. Press [ENTER] to execute the change.
Programs the Eb/N0 target setpoint.
MAX TR
On entry, the current Eb/N0 target setpoint is displayed with the flashing
cursor on the first character. Use the arrow keys to increment or decrement
the digit at the flashing cursor. The Eb/N0 target setpoint can range from 3.2
to 9.7 dB, in 0.1 dB increments. Press [ENTER] to execute the change.
Programs the maximum tracking rate of the AUPC.
LOCAL CL
On entry, the current maximum tracking rate is displayed with the flashing
cursor on the first character. Use the arrow keys to increment or decrement
the digit at the flashing cursor. The maximum tracking rate can range from
0.5 to 6 dBm/minute. Press [ENTER] to execute the change.
Programs the local carrier loss for maximum, nominal, or hold.
REMOTECL
On entry, the current status of the local carrier loss is displayed with the
flashing cursor on the first character. Use the arrow keys to select maximum,
nominal, or hold. Press [ENTER] to execute the change.
Programs the remote carrier loss for maximum, nominal, or hold.
On entry, the current status of the remote carrier loss is displayed with the
flashing cursor on the first character. Use the arrow keys to select maximum,
nominal, or hold. Press [ENTER] to execute the change.
F–28
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.5.2.2 Select Monitor
Refer to Table F-8.
When the Monitor level is entered, use [←] and [→] to select the desired monitor function.
Each monitor function is displayed in real time as long as it is selected.
Function
Raw_BER
Cor_BER
Eb/N0
SWP Freq
Fil_Stat
RXSignal
RX 2047
Description
Raw bit error rate.
Range: < 1.0E-4 to 2550E-4
Corrected bit error rate.
Range: < 1.0E-8 to > 1E-3
Energy(bit)/noise ratio.
Range: < 3.2 to > 9.7 dB
Sweep monitor.
Range: -30,000 to +30,000 Hz
Plesiochronous buffer fill status in percent.
Range: 1% to 99%
Receive signal level.
Range: < -60 to -30 dBm
Receive 2047 BER.
Range: < 1.0E-3 to > 1E-6, < 1E-6, or no data
(See Note)
(See Note)
(See Note)
(See Note)
(See Note)
Note: When the decoder loses lock, no data is available, and is so indicated.
Rev. 5
F–29
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.5.2.3 Select Faults
Refer to Table F-9.
The Faults level is accessible from the Select menu. Faults are similar to monitor
functions, they display the current fault status of the group being displayed. Use [←] and
[→] to move between the following fault groups:
•
•
•
•
•
MOD FLTS (modulator faults)
DMD FLTS (demodulator faults)
CEQ FLTS (common equipment faults)
TX_INTF (transmitter interface faults)
RX_INTF (receiver interface faults)
The current fault status is displayed on line 2 of the display in real time. Fault status is
displayed as “+” or “-” for each parameter monitored.
•
•
“+” indicates that a fault exists.
“-” indicates that no fault exists.
Press [ENTER] to display labels for individual faults.
Use [←] and [→] to move the flashing cursor to the fault that is to be identified. The label
for that fault is immediately displayed on line 1 of the display. Use [CLEAR] to exit this
level of operation and return to the previous level.
The following sections outline the faults monitored and displayed in each group.
F–30
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.5.2.3.1 Modulator Faults (Mod_FLTS)
RF_Syn
Data Clk
TClk Syn
I-Channl
Q-Channl
AGC_levl
Module
Modulator RF synthesizer fault.
Transmit data clock activity fault.
Transmit clock synthesizer fault.
I channel activity fault.
Q channel activity fault.
Automatic gain control level fault.
Modulator module fault. Typically indicates that the modulator module is
missing or will not program.
Refer to Section 6.2 for option explanations.
F.5.2.3.2 Demodulator/Decoder Faults (Dmd_Flts)
C_Detect
RF_Syn
Data_Clk
I-Channl
Q-Channl
Dscrambl
BERthrsh
Module
Carrier detect fault. Typically indicates that the decoder is not locked.
Demodulator RF synthesizer fault.
Receive data clock activity fault.
I channel activity fault.
Q channel activity fault.
Descrambler activity fault.
Bit Error Rate threshold fault.
Demodulator/decoder module fault. Typically indicates that the
demod/decoder module is missing or will not program.
Refer to Section 6.2 for option explanations.
F.5.2.3.3 Common Equipment Faults (CEq_Flts)
Battery
-12 volt
+12 volt
+5 volt
Controlr
Battery fault.
-12V power supply fault.
+12V power supply fault.
+5V power supply fault.
Controller fault.
Intrface
Typically indicates that the controller has gone through a power ON-OFF
cycle.
Interface module fault.
Typically indicates that the interface module is missing or will not program. If
using an RS-422 interface module, this fault could indicate the address
jumper settings of JP4 through JP7 are not properly set. Refer to Chapter 3
for more information.
Refer to Section 6.2 for option explanations.
Rev. 5
F–31
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.5.2.3.4 Transmit Faults (TX_INTF)
The faults listed below are only displayed when the ASYNC overhead channel unit is
installed.
Refer to Section 6.2 for option explanations.
TX_PLL
Clk_Act
Interface transmit clock phase locked loop fault.
Clock activity fault.
Activity detector alarm of the selected interface clock. The interface will fall
back to the internal clock when this fault is active.
F.5.2.3.5 Receive Faults (RX_INTF)
The faults listed below are only displayed when the ASYNC overhead channel unit is
installed.
Refer to Section 6.2 for option explanations.
BUF_UNFL
Buffer underflow fault.
BUF_OVFL
Typically indicates that a buffer underflow has occurred.
Buffer overflow fault.
RX_PLL
Buff_Clk
Typically indicates that a buffer overflow has occurred.
Interface receive clock phase locked loop fault.
Buffer clock activity fault.
MUX_lock
Activity detector alarm of the selected interface receive clock.
MUX lock fault.
Typically indicates that the MUX is not locked.
F–32
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.5.2.4 Select Stored Faults (StFaults)
Refer to Table F-10.
The modem stores the first 10 (Flt0 to Flt9) occurrences of fault status changes in each of
the six major fault categories. Each stored fault status change is stored with the time and
date of the occurrence. Stored faults may be viewed by entering the StFaults level from
the Select menu. All stored faults may be cleared by executing the “CLEAR ?? StFaults”
command from the StFaults level.
Stored faults are not maintained through a controller power-on reset cycle. However, the
last known time is maintained in non-volatile RAM. Upon power-up, a common
equipment fault is logged (Flt0) with that time and date. Also upon power-up, an
additional common equipment fault is also logged (Flt1) to indicate the power-up time
and date.
On power-up, the power-down and power-up times are logged as common equipment
fault 0 and common equipment fault 1, respectively.
Upon entering the StFaults level, use [←] and [→] to move between the six fault groups
and the “CLEAR ?? StFaults” selections. The time and date of the first stored fault status
(Flt0) for the selected group will be displayed alternately on line 2 of the display. Use [↑]
and [↓] to cycle through the selected group’s stored fault status (Flt0 to Flt9). Press
[ENTER] to display the fault status associated with the displayed time and date. At this
time, use [←] and [→] to move the flashing cursor to the fault to be identified.
To clear the stored faults currently logged, press [ENTER] when the “CLEAR ??
StFaults” selection is displayed.
Note: Faults are stored in time sequence, with the oldest fault status change stored in
Flt0, and the most recent in Flt9. Only the first 10 fault status changes are stored. All
stored faults which have not been used indicate “No Fault” on the display.
Rev. 5
F–33
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
F.5.2.5 Select Remote
Refer to Table F-11.
The remote functions may be viewed or changed by entering the Remote level from the
Select menu on the front panel. After entering the Remote menu, use [←] and [→] to select
Config or Monitor configuration. Enter the selected Configuration menu by pressing
[ENTER]. Use [←] and [→] to view the selected configuration parameters.
The following sections contain information on individual functional categories and their
respective functions.
F.5.2.5.1 Remote Configuration
AUPC
Remote AUPC enable.
BBLOOPBK
On entry, the current status of the remote AUPC is displayed with the flashing
cursor on the first character. Use the arrow keys to select ON or OFF. Press
[ENTER] to execute the change.
Programs the remote baseband loopback or ON or OFF.
TX 2047
On entry, the current status of the remote baseband loopback is displayed with
the flashing cursor on the first character. Use the arrow keys to select ON or
OFF. Press [ENTER] to execute the change.
Programs the remote TX 2047 pattern ON or OFF.
On entry, the current status of the remote TX 2047 is displayed with the flashing
cursor on the first character. Use the arrow keys to select ON or OFF. Press
[ENTER] to execute the change.
F.5.2.5.2 Remote Monitor
RX 2047
F–34
Receive 2047 BER. This is a monitor point that will display the current RX 2047
BER. If no data is available, the display will read “No Data.”
Rev. 5
SDM-650B Satellite Modem
Asynchronous Overhead Channel Unit
F.5.2.6 Select Utility
Refer to Table F-12.
The Utility functions provide a means to set the time and date of the modem real time
clock circuit. Provisions are also made for assigning data and code rates to the modulator
and demodulator. A lamp test function is provided for testing of the front panel optical
indicators. Access to the transmitter and receiver data/code rate assignments are also
available from within the Utility menu.
After entering the Utility menu, use [←] and [→] to select the Utility function of interest.
The current time and date can be displayed and changed as required.
Note: The selection of data/code rates in the utility program must match the hardware
filters installed on the modulator and demodulator modules.
The utility functions are as follows:
Time
Time of day set/display function.
Date
The current time in the modem’s memory is displayed when
selected. To change the time, press [ENTER]. Use [←] and
[→] to position the flashing cursor over the parameter to be
changed. Use [↑] and [↓] to change the parameter to the
desired value. Once the parameters are displayed as desired,
press [ENTER] to set the time.
Date set/display.
LAMP TEST ??
Address/Parity/Baud Rate
Rev. 5
The current date in the modem’s memory is displayed when
selected. To set the date, press [ENTER]. Use [←] and [→] to
position the flashing cursor over the parameter to be changed.
Use [↑] and [↓] to change the parameter to the desired value.
Once the parameters are displayed as desired, press
[ENTER] to set the date.
Lamp test function illuminates all the front panel indicators for
three seconds. Press [ENTER] to turn ON all of the front panel
indicators for three seconds.
The current buffer address, parity selection, and the selected
baud rate of the buffer are displayed. This is only a monitor
function. No changes can be made from this menu.
F–35
Asynchronous Overhead Channel Unit
POW ADJ
SDM-650B Satellite Modem
Modulator power adjust offset.
Allows the operator to offset the modulator output power
readout in the Config menu. This will be the highest modulator
power that will be displayed and programmed. This feature
does not actually change the modulator power level. The
function is to change the actual reading to display an offset
value in the monitor. The modulator power offset can be set
between +20.00 to -20 dB, in 0.5 dB increments.
OP MODE
Note: The maximum output power adjust, set in this window,
must match the maximum output power of the modulator
installed in the modem. In a switching system, the backup
modem must be set the same as the prime modem or a fault
will occur.
Operation mode.
Programs the modem operation for TX-only, RX-only, or
Duplex operation.
FAST ACQ
On entry, the flashing cursor is on the first character of the
display. Use the arrow keys to select TX-only, RX-only, or
Duplex. Press [ENTER] to execute the change. When TX-only
or RX-only is selected, the appropriate faults are masked from
the Faults and Stored Faults (StFaults) menu.
Fast Acquisition function.
Turns the fast acquisition and directed sweep function ON or
OFF.
When Fast Acquisition has been turned OFF, the Swp_Cntr,
SWP_Rnge, and SWP_DIR windows in the Config menu are
disabled and do not appear. Also, in the Monitor menu,
Swp_Freq will not appear. When turned OFF, Fast Acquisition
does not occur.
FILTERS ADJUST
INT-TYPE RS-422, V.35
F–36
Note: Fast acquisition only applies to data rates of 256 kbit/s
and below. If the sweep range is set to less than 50 kHz,
acquisition will be dictated by the directed sweep
specifications. The fast acquisition algorithm will not be used.
This is a factory setting, and the operator is not allowed to
enter this parameter without authorization from the EFData
Customer Support Department. Failure to comply will result in
a modem failure.
Rev. 5
SDM-650B Satellite Modem
Assign TX_Fltrs
Asynchronous Overhead Channel Unit
Transmit filter display/assignment utility. Used to view current
filter rate assignments and to make filter rate reassignments.
The modulator has four symbol rate filters. Each filter is for a
specific symbol rate. The data rate and code rate for each
filter must be established upon initial modulator installation,
and when circumstances indicate the need to do so. Filters
are designated as A, B, C, and D. Press [ENTER] when the
Assign TX-Fltrs selection is displayed in the Utility Functions
menu to view the current filter assignments. On line 1 of the
display will be TXA, which indicates transmitter filter A.
Following TXA on line 1 will be the code rate (1/2, 3/4, or 7/8)
or N/A (not assigned). On line 2 will be the data rate assigned
to filter A. Use [←] and [→] to see the assignments for filters B,
C, and D (TXB, TXC, and TXD). To change a filter
assignment, press [ENTER] when the data for that filter is
displayed. Use [←] and [→] until the flashing cursor is at the
parameter to be changed. Use [↑] and [↓] to change that
parameter. When all changes are made, press [ENTER] to
confirm the assignment. Some filters may have parameters
preprogrammed in the filter board hardware. If the filter
parameters are preprogrammed, the previously described
programming techniques will be disabled.
Assign RX_Fltrs
Note: These assignments are used for the selection of TXR in
the Configuration Functions menu. The parameter N/A is used
to indicate that the specific filter is not present.
Receive filter display/assignment utility. Used to view current
filter rate assignments and to make filter rate reassignments.
The modulator has four symbol rate filters. Each filter is for a
specific symbol rate. The data rate and code rate for each
filter must be established upon initial modulator installation,
and when circumstances indicate the need to do so. Filters
are designated as A, B, C, and D. Press [ENTER] when the
Assign RX-Fltrs selection is displayed in the Utility Functions
menu to view the current filter assignments. On line 1 of the
display will be RXA, which indicates transmitter filter A.
Following RXA on line 1 will be the code rate (1/2, 3/4, or 7/8)
or N/A (not assigned). On line 2 will be the data rate assigned
to filter A. Use [←] and [→] to see the assignments for filters B,
C, and D (RXB, RXC, and RXD). To change a filter
assignment, press [ENTER] when the data for that filter is
displayed. Use [←] and [→] until the flashing cursor is at the
parameter to be changed. Use [↑] and [↓] to change that
parameter. When all changes are made, press [ENTER] to
confirm the assignment. Some filters may have parameters
preprogrammed in the filter board hardware. If the filter
parameters are preprogrammed, the previously described
programming techniques will be disabled.
Rev. 5
F–37
Asynchronous Overhead Channel Unit
SDM-650B Satellite Modem
This page is intentionally left blank.
F–38
Rev. 5
Appendix G.
TROJAN INTERFACE
This appendix provides information on the Trojan interface option for the SDM-650B,
including:
•
•
•
•
•
•
Functional description
Connector pinouts
Specifications
Configuration guidelines
Front panel operation information
Remote control operation information
G.1 Functional Description
The Asynchronous Dejittered MIL-STD-188-114 digital interface provides level
translation, buffering, jitter reduction, and termination between the modem internal
signals and the MIL-STD-188-114 DCE interface on the rear panel. This interface also
has the capability to handle different rates of transmit and receive data, using an internal
synthesizer to generate the respective clocks. Also included in the receive chain is a
selectable depth Doppler buffer to handle satellite delay variation.
Refer to Figure G-1 for a block diagram of this interface.
Control of interface parameters is accomplished from the front panel (refer to Chapter 4)
through the Config Interface menu. Remote control may be accomplished through the
RS-232-C/-485 port (refer to Section G.6).
Rev. 5
G–1
Trojan Interface
SDM-650B Satellite Modem
The data rate synthesizer may take its input reference clock (REF_CLK) from one of four
different sources:
•
•
•
•
Transmit clock
Receive clock
External Station Clock (MC)
Internal clock (SCT)
The phase-lock loop which locks to the reference has a very narrow bandwidth,
effectively dejittering the reference. The phase-lock loop can handle data rates from
32 kbit/s to 2.048 Mbit/s, in steps of 8 kHz. Transmit and receive data rates do not need
to be the same. If used, External Station Clock may range from 32 kHz to 10 MHz, in
steps of 8 kHz.
The Doppler buffer depth ranges from 512 to 32768 bits, in powers of 2. The buffer is
centered on power-up, start of service (when the modem receive section locks), or in case
of underflow or overflow. The buffer may also be centered manually. Buffer overflow
and underflow are logged as stored faults so that clock offset information may be
obtained.
RX DATA
TO CUSTOMER
MODEM RX DATA
DOPPLER
BUFFER
RX CLOCK
TO CUSTOMER
MODEM RX CLOCK
STATION
REFERENCE
MODEM SCT CLOCK
DIVIDE
BY
N
8 KHZ
8 KHZ
RECEIVE
CLOCK LOOP
PHASE DETECTOR
RECEIVE
CLOCK LOOP
FILTER
VOLTAGE
CONTROLLED XTAL
OSCILLATOR
4.096 MHZ
DEJITTERED
DIVIDE
BY
512
8 KHZ
8 KHZ
RECEIVE
CLOCK LOOP
PHASE DETECTOR
RECEIVE
CLOCK LOOP
FILTER
8 KHZ
RECEIVE
VCO FREQUENCY
(SEE TABLE)
DEJITTERED
DIVIDE
BY
K
DIVIDE
BY
L
8 KHZ
VOLTAGE
CONTROLLED
OSCILLATOR
RECEIVE
CLOCK LOOP
FILTER
RECEIVE
CLOCK LOOP
PHASE DETECTOR
DIVIDE
BY
P
VOLTAGE
CONTROLLED
OSCILLATOR
TRANSMIT
VCO FREQUENCY
(SEE TABLE)
DEJITTERED
DIVIDE
BY
M
TX DATA RATE
CLOCK
TO CUSTOMER
TX DATA
FROM CUSTOMER
TX CLOCK
FROM CUSTOMER
MODEM TX DATA
FIFO
BUFFER
MODEM TX CLOCK
INT/EXT
TX CLOCK
Figure G-1. Trojan Interface Block Diagram
G–2
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
Receive
Data Rate
(kbit/s)
N
K
L
56
64
128
256
512
1024
1544
2048
7
8
16
32
64
128
193
256
64
64
32
16
8
4
2
2
7
8
16
32
64
128
193
256
Receive
Data Rate
(kbit/s)
K
L
56
64
128
256
512
1024
1544
2048
64
64
32
16
8
4
2
2
7
8
16
32
64
128
193
256
Receive
VCO
Frequency
(kHz)
3584
4096
4096
4096
4096
4096
3088
4096
Receive
VCO
Frequency
(kHz)
3584
4096
4096
4096
4096
4096
3088
4096
The MIL-STD-188-114 interface provides a Send Timing (ST) clock signal at the modem
transmit data rate. In the INTERNAL clock mode, the data to be transmitted, Send Data
(SD), must be synchronized to ST. In the EXTERNAL clock mode, clock is accepted on
the Terminal Timing input (TT) to clock in the data to be transmitted. In either case, the
phase relationship between the clock and data is not important, so long as it meets the
jitter specifications of MIL-STD-188-100, because a clock phase correction circuit is
provided, which shifts the clock away from the data transition times. If EXTERNAL
clock mode is used, the clock must be long-term synchronous with the synthesizer
reference, unless it is selected to “Transmit” clock.
Data received by the modem is output on the Receive Data (RD) lines, while the
recovered clock is output on the Receive Timing (RT) lines. For applications that require
the rising edge of the clock to occur in the middle of the data bit time, Receive Clock
NORMAL mode should be selected. INVERT mode puts the falling edge of RT in the
middle of the data bit.
The Request to Send (RS) lines are hard-wired to the Clear to Send (CS) lines, since the
modem does not support polled operation.
Data Mode (DM) indicates that the modem is powered up.
Rev. 5
G–3
Trojan Interface
SDM-650B Satellite Modem
Receiver Ready (RR) indicates that an RF carrier is being received and demodulated with
a sufficiently low error rate for the decoder to remain locked.
The MIL-STD-188-114 interface also provides bi-directional relay loopback of both the
clock and data at the DCE interface. In LOOPBACK from the DTE side, SD is connected
to RD, and either ST or TT (in INTERNAL or EXTERNAL mode) is looped back to RT.
From the modem side, the received data and recovered clock are routed back to the
modulator input for retransmission. During loopback, the synthesizer clock source is
automatically set to Receive Clock for reasons of stability.
Three fault outputs are provided on dry contact Form C relays:
•
•
•
Common Equipment
Modulator
Demodulator
They are available on the FAULT connector on the modem rear panel.
Fault indicators are also provided on TTL open collector drivers on the MIL-STD-188114 connector. The TTL MOD fault indicates a MODULATOR fault or COMMON
EQUIPMENT fault, while the TTL DEMOD fault indicates a DEMOD or COMMON
EQUIPMENT fault.
G–4
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.2 Connector Pinouts
The Asynchronous dejittered MIL-STD-188-114 interface is provided on a 37-pin female
D connector accessible from the rear panel of the modem.
Screw locks are provided for mechanical security of the mating connector.
Signal Function
SIGNAL GROUND
SEND DATA
SEND TIMING
RECEIVE DATA
REQUEST TO SEND
RECEIVER TIMING
CLEAR TO SEND
DATA MODE
RECEIVER READY
TERMINAL TIMING
STATION REF TIMING
MODULATOR FAULT
DEMODULATOR FAULT
Rev. 5
Name
SG
SD-A
SD-B
ST-A
ST-B
RD-A
RD-B
RS-A
RS-B
RT-A
RT-B
CS-A
CS-B
DM-A
DM-B
RR-A
RR-B
TT-A
TT-B
MC-A
MC-B
MF
DF
Pin #
1, 19, 20, 37
4
22
5
23
6
24
7
25
8
26
9
27
11
29
13
31
17
35
16
34
3
21
G–5
Trojan Interface
SDM-650B Satellite Modem
G.3 Specification
G.3.1 MIL-STD-188-114 Parameters
Circuit Supported
Amplitude (RD, RT, ST, DM, RR)
DC Offset (RD, RT, ST, DM, RR)
Impedance (RD, RT, ST, DM, RR)
Impedance (SD, TT, MC)
Polarity
Phasing (TT, RT)
Symmetry (ST, TT, RT)
Frequency Stability (ST)
Modulator Fault
Demodulator Fault
SD, ST, TT, RD, RT, DM, RR, MC, MOD FAULT,
DEMOD FAULT.
4, ± 2V differential into 100Ω.
± 0.4V.
Less than 100Ω, differential.
100, ± 20Ω, differential.
True when B positive with respect to A.
False when A positive with respect to B.
False-to-true transition nominally in center of data bit.
50%, ± 5%.
± 100 ppm.
Open collector output, 15V max, 20 mA max current
sink. Fault is open circuit.
Open collector output, 15V max, 20 mA max current
sink. Fault is open circuit.
G.3.2 Clock Synthesizer/Dejitter Circuit
Reference Clk Sources
Reference Clk Input
Synthesized TX Clock
Synthesized RX Clock
Jitter Gain
Transmit Clk
Receive Data Clk
External Reference Clk (MC)
Modem Internal Clk (SCT)
32 kHz to 10 MHz, in 8 kHz steps
56 to 2048 kHz, in 8 kHz steps
56 to 2048 kHz, in 8 kHz steps
Synth Clk Freq/Ref Clk Freq, modified by a 1-pole
(20 dB/decade) low-pass response corner at 0.4 Hz
G.3.3 Doppler Buffer Parameters
Buffer Size (bits)
Clock Source
Data Rate
Indicators
Controls
Misc.
G–6
512, 1024, 2048, 4096, 8192, 16384, 32768
Synthesized RX Clock
56 to 2048 kbit/s
Buffer Overflow (stored fault)
Buffer Underflow (stored fault)
Reset Buffer to Center
Buffer Depth
Buffer automatically recenters on Over/Underflow,
power-on, or start of service
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.4 Configuration Guide
Menu Selection
BBLoopBk (Baseband Loopback)
EXT_REF (Station Clock Freq)
REF_CLK (Ref Clock Source)
TX_clock
RX_clock
BUF_CNTR (Center Doppler Buffer)
BUF_DPTH (Buffer Depth, bits)
Options
OFF/ON
n kHz (must be evenly divisible by 8 kHz)
Transmit
Receive
External (MC)
Internal (SCT)
External (TT)
Internal (Synthesizer)
Normal/Inverted
YES/NO
512 bit
1024 bit
2048 bit
4096 bit
8192 bit
16384 bit
32768 bit
Notes:
1. Reference clock source is temporarily set to Receive clock during baseband
loopback.
2. Do not set TX_clock to REF_CLK when REF_CLK source is TX_clock, as
this makes an unstable loop.
3. Send Data (SD) must be long-term synchronous with Send Timing (ST),
unless REF_CLK source is Transmit and TX_clock is External (this is the
recommended dejitter configuration).
4. EXT_REF frequency selection is a “don’t care” unless REF_CLK is selected
to External. The M&C processor automatically sets the proper division rate
for the clock synthesizer in the other cases.
G.4.1 Modulator/Coder Defaults
TXA
TXB
TXC
TXD
TXR
TX_Freq
RF_Out
TX_Power
Scramblr
DifEncdr
CW_Mode
Rev. 5
Transmit Filter A
Transmit Filter B
Transmit Filter C
Transmit Filter D
Transmit Rate Selected
Transmitter Frequency
RF Output
Transmit Power Level
Scrambler
Differential Encoder
Continuous Wave Mode
7/8 code rate, 56 kbit/s
3/4 code rate, 56 kbit/s
1/2 code rate, 56 kbit/s
1/2 code rate, 64 kbit/s
“A” 7/8, 56 kbit/s
70 MHz
OFF
-10 dBm
ON
ON
OFF
G–7
Trojan Interface
SDM-650B Satellite Modem
G.4.2 Demodulator/Decoder Defaults (Dmd_Flts)
RXA
RXB
RXC
RXD
RXR
RX-Freq
Dscrmblr
IFLoopBK
RFLoopBK
SWP-RACQ
SWP-CNTR
SWP-RNGE
SWP-DIR
BERThsld
Receive Filter A
Receive Filter B
Receive Filter C
Receive Filter D
Receive Rate Selected
Receiver Frequency
Descrambler
IF Loopback
RF Loopback
Sweep Re-acquisition
Sweep Center
Sweep Range
Sweep Direction
BER Threshold
7/8 decode rate, 56 kbit/s
3/4 decode rate, 56 kbit/s
1/2 decode rate, 56 kbit/s
1/2 decode rate, 64 kbit/s
“A” 7/8, 56 kbit/s
70 MHz
ON
OFF
OFF
0 Sec
0 Hz
5000 Hz
Forward
None
Baseband Loopback
Reference Clock
Transmit Clock
Receive Clock
Buffer Depth
OFF
Transmit
REF_clk
Normal
512 bits
G.4.3 Interface Defaults
BBLOOPBK
REF_CLK
TX_CLOCK
RX_CLOCK
BUF_DPTH
G–8
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.5 Front Panel Operation
The operation of the front panel has the same “look and feel” as the standard modem,
except there are a few additional commands for the Trojan interface.
Note: For general information on front panel operation, refer to Chapter 4.
Refer to Tables G-1 through G-8 for front panel menus and options for the SDM-650B
with the Trojan interface option installed.
G.5.1 Menus and Options Overview
Refer to Section G.5.2 for menu and option explanations.
The “T” after the software version designates “Trojan.”
Table G-1. Main Front Panel Menu (Trojan Interface)
Menus
SDM-650S
SW_4.13T
SELECT CONFIG
SELECT MONITOR
SELECT FAULTS
SELECT StFAULTS
SELECT UTILITY
Rev. 5
Submenus/Options
Comments
This is an information-only screen.
MOD
DEMOD
INTRFACE
Raw_BER
Corr_ BER
Eb/NO
SWP_FREQ
RXSignal
MOD Flts
DMD Flts
Ceq Flts
MOD
DMD Flts
Ceq Flts
CLEAR??
Time
Date
LAMP TEST??
ADD/PARITY/BAUD RATE
POW ADJ
OP MODE
FAST ACQ
FILTERS ADJUST
Assign TX_Fltrs
Assign RX_Fltrs
Go to Table G-2.
Go to Table G-3.
Go to Table G-4.
Go to Table G-5.
Go to Table G-5.
Go to Table G-5.
Go to Table G-5.
Go to Table G-5.
Go to Table G-6.
Go to Table G-6.
Go to Table G-6.
Go to Table G-7.
Go to Table G-7.
Go to Table G-7.
Go to Table G-7.
Go to Table G-8.
Go to Table G-8.
Go to Table G-8.
Go to Table G-8.
Go to Table G-8.
Go to Table G-8.
Go to Table G-8.
Go to Table G-8.
Go to Table G-8.
Go to Table G-8.
G–9
Trojan Interface
SDM-650B Satellite Modem
Table G-2. Select Configuration Modulator Menu
Menus
Submenus/Options
TX-x Code_Rate
x = A, B, C, D, or V
TX_Freq
50.0000 to 90.0000 MHz
or 100.000 to 180.000 MHz
ON
OFF
-5.0 dBm to -25 dBm
RF_Out
TX_Power
Scramblr
Comments
In 2.5 kHz steps.
In 0.5 dBm steps.
ON
OFF
ON
OFF
Center
Dual
Offset
DifEncdr
CW_Mode
Table G-3. Select Configuration Demodulator Menu
Menus
Comments
x = A, B, C, D, or V
RX_Freq
In 2.5 kHz steps.
SWP_RACQ
50.000 to 90.0000 MHz
or 100.000 to 180.000 MHz
ON
OFF
ON
OFF
ON
OFF
0 to 999 Seconds
SWP_CNTR
-25000 to +25000 Hz
SWP_RNGE
0 to 50000 Hz
SWP_DIR
FORWARD +
REVERSE -
Displays information when fast
acquisition has been turned ON in the
Utility menu.
Displays information when fast
acquisition has been turned ON in the
Utility menu.
Displays information when fast
acquisition has been turned ON in the
Utility menu.
BERT_set
1E-3
1E-4
1E-5
1E-6
1E-7
1E-8
NONE
Dscrmblr
IFLoopBk
RFLoopBk
G–10
Submenus/Options
RX-x Code Rate
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
Table G-4. Select Configuration Interface Menu
Menus
TX_Clock
Submenus/Options
BUF_CNTR
REF_CLK
External
Normal
Inverted
YES/NO?
BUF_DPTH
512 to 32768 bits
BBLoopBk
ON
OFF
8 kHz to 10 MHz
RX_Clock
EXT_REF
Ref_Clk
Comments
In 8 kHz steps.
Transmit
Receive
External
Internal
Table G-5. Select Monitor Menu
Raw_BER
Menus
Submenus/Options
Range: < 1.0E-4 to 2550E-4
Corr_BER
Range: > 1E-8 to > 1E-3
Eb/N0
Range: < 3.2 dB to > 9.7 dB
SWP FREQ
Range: -25000 to +25000 Hz
RXSignal
Range: < -60 dBm to > -30 dBm
Comments
Displays information when fast
acquisition has been turned ON in
the Utility menu.
Note: Data is not available or displayed when the decoder loses lock.
Rev. 5
G–11
Trojan Interface
SDM-650B Satellite Modem
Table G-6. Select Faults (StFaults) Menu
Menus
Mod Flts
Dmd Flts
CEq Flts
Submenus/Options
RF_Syn
Data_Clk
TClk_Syn
I-Channl
Q-Channl
AGC_levl
Module
C_Detect
RF_Syn
Data_Clk
I-Channl
Q-Channl
Dscramblr
BERthrsh
Module
Battery
-12 volt
+12 volt
+5 volt
BUF_UNFL
BUF_OVFL
Controlr
Intrface
Comments
Note: Fault conditions are displayed as a “+” on the screen.
G–12
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
Table G-7. Select StFaults Menu
Menus
Mod Fltx
MM/DD/YY
HH/MM/SS
Dmd Fltx
MM/DD/YY
HH/MM/SS
CEq Fltx
MM/DD/YY
HH/MM/SS
CLEAR ??
StFaults
Submenus/Options
RF_Syn
Data_Clk
TClk_Syn
I-Channl
Q-Channl
AGC_levl
Module
C_Detect
RF_Syn
Data_Clk
I-Channl
Q-Channl
Dscrambl
BERthrsh
Module
Battery
-12 volt
+12 volt
+5 volt
BUF_UNFL
BUF_OVFL
Controlr
Intrface
YES/NO
Comments
Mod Flt0 through Mod Flt9.
Dmd Flt0 through Dmd Flt9.
CEq Flt0 through CEq Flt9.
Table G-8. Select Utility Menu
Menus
Comments
Seconds (SS). Reset at [ENTER].
Date
Submenus/Options
SS
HH:MM AM/PM
MM/DD/YY
LAMP TEST??
YES
Press [ENTER] to illuminate all front
panel LEDs for three seconds.
Add: 1
xxxxyyyy
Address = 0 to 255
xxxx = Parity
Odd
Even
yyyy = 110 to 9600 Baud Rate
+20 dBm to -20 dBm
Time
POW ADJ
OP MODE
FAST ACQ
FILTERS ADJUST
TX ONLY
RX ONLY
DUPLEX
ON
OFF
MOD ADJ.
DMD ADJ.
Assign TX_Fltrs
Filters = A, B, C, D, or V
Assign RX_Fltrs
Filters = A, B, C, D, or V
Rev. 5
In 0.5 dBm steps.
This is a factory setting and should
not be changed by unauthorized
persons.
G–13
Trojan Interface
SDM-650B Satellite Modem
G.5.2 Menu Explanations
Note: Only the differences between the standard front panel menus and the Trojan
interface menus are discussed in this section.
G.5.2.1 Select Configuration
Refer to Chapter 4 for explanations of menus and options.
G.5.2.2 Select Monitor
Refer to Chapter 4 for explanations of menus and options.
G.5.2.3 Select Faults
Refer to Chapter 4 for explanations of menus and options.
G.5.2.3.1 Modulator Faults (Mod_Flts)
Refer to Chapter 4 for explanations of menus and options.
G.5.2.3.2 Demodulator/Decoder Faults (Dmd_Flts)
Refer to Chapter 4 for explanations of menus and options.
G.5.2.3.3 Common Equipment Faults (CEq_Flts)
Refer to Table H-6. (Refer to Chapter 4 for explanations of menus and options that are
not provided in this section.)
BUF_UNFL
Buffer underflow fault.
BUF_OVFL
Indicates that a plesiochronous buffer underflow has occurred.
Buffer overflow fault.
Indicates that a plesiochronous buffer overflow has occurred.
G–14
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.5.2.4 Select Stored Faults (StFaults)
Refer to Chapter 4 for explanations of menus and options.
G.5.2.5 Select Utility
Refer to Chapter 4 for explanations of menus and options.
Rev. 5
G–15
Trojan Interface
SDM-650B Satellite Modem
G.6 Remote Control Operation
This section describes the remote control operation of the SDM-650B with the Trojan
interface installed.
•
•
Firmware number:
Software version:
FW/0713-70A
4.13T
G.6.1 General
Remote controls and status information are transferred via an RS-485 (optional RS-232-C)
serial communications link.
Commands and data are transferred on the remote control communications link as
US ASCII-encoded character strings.
The remote communications link is operated in a half-duplex mode. Communications on the
remote link are initiated by a remote controller or terminal.
The modem never transmits data on the link unless it is commanded to do so.
G.6.1.1 Message Structure
The ASCII character format used requires 11 bits/character:
•
•
•
•
1 start bit
7 information bits
1 parity bit (odd/even)
2 stop bits
Messages on the remote link fall into the categories of commands and responses.
Commands are messages which are transmitted to a satellite modem, while responses are
messages returned by a satellite modem in response to a command.
The general message structure is as follows:
•
•
•
•
G–16
Start Character
Device Address
Command/Response
End of Message Character
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.1.1.1 Start Character
A single character precedes all messages transmitted on the remote link. This character flags
the start of a message. This character is:
•
•
“<” for commands
“>” for responses
G.6.1.1.2 Device Address
The device address is the address of the one satellite modem which is designated to receive
a transmitted command, or which is responding to a command.
Valid device addresses are 1 to 3 characters long, and in the range of 1 to 255. Address 0 is
reserved as a global address which simultaneously addresses all devices on a given
communications link. Devices do not acknowledge global commands.
Each satellite modem which is connected to a common remote communications link must
be assigned its own unique address. Addresses are software selectable at the modem, and
must be in the range of 1 to 255.
Rev. 5
G–17
Trojan Interface
SDM-650B Satellite Modem
G.6.2 Command/Response
The command/response portion of the message contains a variable length character
sequence which conveys command and response data.
If a satellite modem receives a message addressed to it which does not match the established
protocol or cannot be implemented, a negative acknowledgment message is sent in
response. This message is:
•
>add/?ER1_PARITY ERROR”cr””lf”]
(Error message for received parity errors.)
•
>add/?ER2_INVALID PARAMETER”cr””lf”]
(Error message for a recognized command which cannot be implemented or has parameters which
are out of range.)
•
>add/?ER3_UNRECOGNIZABLE COMMAND”cr””lf”]
(Error message for unrecognizable command or bad command syntax.)
•
>add/?ER4_MODEM IN LOCAL MODE”cr””lf”]
(Modem in local error; use the REM command to go to remote mode.)
•
>add/?ER5_HARD CODED PARAMETER”cr””lf”]
(Error message indicating that the parameter is hardware dependent and may not be changed
remotely.)
Note: “add” is used to indicate a valid 1 to 3 character device address in the range
between 1 and 255.
G.6.3 End Character
Each message is ended with a single character which signals the end of the message:
•
•
G–18
“cr”
“]”
Carriage return character for commands
End bracket for responses
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.4 Configuration Commands/Responses
G.6.4.1 Modulator
G.6.4.1.1 Set Modulator Frequency
Command:
Response:
<add/MF_nnn.nnnn”cr”
>add/MF_nnn.nnnn”cr”
RF_OFF”cr””lf”]
Status Only:
Response:
<add/MF_”cr”
>add/MF_nnn.nnnn”cr””lf”]
Where:
nnn.nnnn = 50.0000 to 90.0000 MHz.
For the 140 MHz modulator, nnn.nnnn = 50.0000 to 90.0000, and 100.0000 to
180.0000 MHz.
Note: When modulator frequency is changed, the RF output is switched OFF.
G.6.4.1.2 Set RF Output
Command:
Response:
<add/RF_xxx”cr”
>add/RF_xxx”cr””lf”]
Status Only:
Response:
<add/RF_”cr”
>add/RF_xxx”cr””lf”]
Where: xxx = ON or OFF.
Rev. 5
G–19
Trojan Interface
SDM-650B Satellite Modem
G.6.4.1.3 Modulator Rate
The modulator has four symbol rate filters. Each filter is for a specific symbol rate. The data
rate and coder rate for each filter must be established upon initial modulator installation, and
when circumstances indicate the need to do so.
Filters are designated as A, B, C, and D. If a filter is not physically present in the system, it
may be assigned N/A (not assigned).
Additionally, filters which are factory programmed may not be remotely programmed, and
will return the “error 5” message when a programming command is issued.
Modulators with the variable rate option installed may have four preprogrammed rates
available by using the filter rate assignment commands. These rates are selected using the
standard “SMRx_” commands. Modems that have the variable rate option installed will
also respond to the special “SMRV_” command.
G.6.4.1.3.1 Modulator Filter Rate Assignment
Command:
Response:
<add/AMRx_nnn_mmmm.m”cr”
>add/AMRx_nnn_mmmm.m”cr””lf”]
Status Only:
Response:
<add/AMRx_”cr”
>add/AMRx_nnn_mmmm.m”cr””lf”]
Where:
x = A, B, C, or D (Filter designator).
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m”may be replaced by "N/A” to indicate “no
assignment.”
Example:
Command:
Response:
G–20
<add/AMRx_N/A”cr”
>add/AMRx_N/A”cr””lf”]
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.4.1.3.2 Select Modulator Rate
Command:
Response:
<add/SMRx_”cr”
>add/SMRx_”cr”
RF_OFF”cr””lf”]
Status Only:
(See the MR command.)
Where: x = A, B, C, or D (Filter designator).
Notes:
1. Setting the modulator turns OFF the RF transmitter.
2. If the modem is commanded to a filter (rate) which is not assigned (N/A), the
error 2 message will be returned.
G.6.4.1.3.3 Select Modulator Rate Variable
Note: This command is only applicable for the variable rate option.
Command:
Response:
<add/SMRV_nnn_mmmm.m”cr”
>add/SMRV_nnn_mmmm.m”cr””lf”]
RF_OFF”cr””lf”]
Status Only:
(See the MR command.)
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: Setting the modulator turns OFF the RF transmitter.
G.6.4.1.3.4 Set Modulator Power Offset
Command:
Response:
<add/MPO_snn.n”cr”
>add/MPO_snn.n”cr””lf”]
Status Only:
Response:
<add/MPO_”cr”
>add/MPO_snn.n”cr””lf”]
Where: snn.n = +20.0 to -20.0, in 0.5 dB increments.
Note: This will be the highest modulator power that will be displayed and programmed.
Use the “MOP_” command to actually change the modulator output power.
Rev. 5
G–21
Trojan Interface
SDM-650B Satellite Modem
G.6.4.1.3.5 Set Modulator Output Power Level
Command:
Response:
<add/MOP_snn.n”cr”
>add/MOP_snn.n”cr””lf”]
Status Only:
Response:
<add/MOP_”cr”
>add/MOP_snn.n”cr””lf”]
Where:
For the 140 MHz modulator, snn.n = +20.0 to -45.0, in 0.5 dB increments.
For the 70 MHz modulator, snn.n = +20.0 to -30.0, in 0.5 dB increments.
Notes:
1. Power levels may be programmed for a maximum value specified by the
modulator power, offset with a range of 25 and 10 dB below the maximum value
for the 140 MHz modulator and the 70 MHz modulator, respectively.
2. See the “MPO_” command specification for more information.
G.6.4.1.3.6 Scrambler Enable
Command:
Response:
<add/SE_xxx”cr”
>add/SE_xxx”cr””lf”]
Status Only:
Response:
<add/SE_”cr”
>add/SE_xxx”cr””lf”]
Where: xxx = ON or OFF.
G.6.4.1.3.7 Differential Encoder Enable
Command:
Response:
<add/DENC_xxx”cr”
>add/DENC_xxx”cr”lf”]
Status Only:
Response:
<add/DENC_”cr”
>add/DENC_xxx”cr”lf”]
Where: xxx = ON or OFF.
G–22
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.4.2 Demodulator
G.6.4.2.1 Set Demodulator Frequency
Command:
Response:
<add/DF_nnn.nnnn”cr”
>add/DF_nnn.nnnn”cr””lf”]
Status Only:
Response:
<add/DF_”cr”
>add/DF_nnn.nnnn”cr””lf”]
Where: For the 140 MGz modulator, nnn.nnnn = 50.0000 to 90.0000, and 100.0000 to
180.0000.
G.6.4.2.2 Demodulator Rate
The demodulator has four symbol rate filters. Each filter is for a specific symbol rate. The
data rate and decoder rate for each filter must be established upon initial demodulator
installation, and when circumstances indicate the need to do so.
Filters are designated as A, B, C, and D. If a filter is not physically present in the system, it
may be assigned “N/A” (not assigned).
Additionally, filters which are factory programmed may not be remotely programmed, and
will return the “error 5” message when a programming command is issued.
Demodulators with the variable rate option installed may have four preprogrammed rates
available by using the filter rate assignment commands. These rates are selected using the
standard “SDRx_” commands. Modems that have the variable rate option installed will also
respond to the special “SDRV_” command. This allows for truly variable rate control while
maintaining compatibility with previous systems.
Rev. 5
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SDM-650B Satellite Modem
G.6.4.2.2.1 Demodulator Filter Rate Assignment
Command:
Response:
<add/ADRx_nnn_mmmm.m”cr”
>add/ADRx_nnn_mmmm.m”cr””lf”]
Status Only:
Response:
<add/ADRx_”cr”
>add/ADRx_nnn_mmmm.m”cr””lf”]
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Decoder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
Example:
Command:
Response:
<add/ADRx_N/A”cr”
>add/ADRx_N/A”cr””lf”]
G.6.4.2.2.2 Select Demodulator Rate
Command:
Response:
<add/SDRx_”cr”
>add/SDRx_”cr””lf”]
Status Only:
(See the DR command.)
Where: x = A, B, C, or D (Filter designator).
Note: If the modem is commanded to a filter (rate) which is not assigned (N/A), the error 2
message will be returned.
G.6.4.2.2.3 Select Demodulator Rate Variable
Note: This command is only applicable for the variable rate option.
Command:
Response:
<add/SDRV_nnn_mmmm.m”cr”
>add/SDRV_nnn_mmmm.m”cr””lf”]
Status Only:
(See the DR command.)
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
G–24
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SDM-650B Satellite Modem
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G.6.4.2.3 Descramble Enable
Command:
Response:
<add/DE_xxx”cr”
>add/DE_xxx”cr””lf”]
Status Only:
Response:
<add/DE_”cr”
>add/DE_xxx”cr””lf”]
Where: xxx = ON or OFF.
G.6.4.2.4 IF Loopback
Command:
Response:
<add/IFL_xxx”cr”
>add/IFL_xxx”cr””lf”]
Status Only:
Response:
<add/IFL_”cr”
>add/IFL_xxx”cr””lf”]
Where: xxx = ON or OFF.
G.6.4.2.5 RF Loopback
Command:
Response:
<add/RFL_xxx”cr”
>add/RFL_xxx”cr””lf”]
Status Only:
Response:
<add/RFL_”cr”
>add/RFL_xxx”cr””lf”]
Where: xxx = ON or OFF.
G.6.4.2.6 Sweep Reacquisition
This command is used to specify time duration of the reacquisition mode. The sweep is
reduced to ± 2500 Hz of the last known lock point. Use of this function may reduce
reacquisition times at low data rates. To inhibit the sweep reacquisition mode, set “SR” to 0
seconds.
Command:
Response:
<add/SR_xxx”cr”
>add/SR_xxx”cr””lf”]
Status Only:
Response:
<add/SR_”cr”
>add/SR_xxx”cr””lf”]
Where: xxx = 0 to 999 (number of seconds).
Rev. 5
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SDM-650B Satellite Modem
G.6.4.2.7 Fast Acquisition Mode
This command is used to enable or disable fast acquisition and directed sweep modes of
operation.
When fast acquisition is enabled, the fast acquisition algorithm (requires hardware
calibration) is used for acquisition of receive symbol rates of 128 kbit/s or lower. However,
if the sweep range is set to less than 50 kHz, acquisition will be dictated by the directed
sweep specifications and the fast acquisition algorithm will not be used.
The directed sweep functions are also available when fast acquisition is enabled. Directed
sweep provides three commands for manipulating the acquisition process. These commands
are “SCF_” (sweep center frequency), “SWR_” (sweep range), and “SD_” (sweep
direction).
Command:
Response:
<add/FAM_xxx”cr”
>add/FAM_xxx”cr””lf”]
Status Only:
Response:
<add/FAM_”cr”
>add/FAM_xxx”cr””lf”]
Where: xxx = ON or OFF (OFF disables fast acquisition and directed sweep modes).
G.6.4.2.8 Sweep Center Frequency
This command sets the sweep center frequency. During carrier acquisition, the sweep starts
at an offset which is one-half the currently programmed sweep range (SWR_) from the
sweep center frequency. The direction of the offset is determined by the currently
programmed sweep direction (SD_).
The sweep center frequency may be set in the range of +25000 to -25000 Hz.
Command:
Response:
<add/SCF_xnnnnn”cr”
>add/SCF_xnnnnn”cr””lf”]
Status Only:
Response:
<add/SCF_”cr”
>add/SCF_xnnnnn”cr””lf”]
Where:
x = + or - (sweep offset direction).
nnnnn = 0 to 25000.
Note: This command is only valid when Fast Acquisition is enabled. See the “FAM_”
command definition.
G–26
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SDM-650B Satellite Modem
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G.6.4.2.9 Sweep Width Range
This command sets the overall travel of the sweep during acquisition. The sweep width may
be set in the range of 0 to 50000 Hz.
Command:
Response:
<add/SWR_nnnnn”cr”
>add/SWR_nnnnn”cr””lf”]
Status Only:
Response:
<add/SWR_”cr”
>add/SWR_nnnnn”cr””lf”]
Where: nnnnn = 0 to 50000.
Note: This command is only valid when Fast Acquisition is enabled. See the “FAM_”
command definition.
G.6.4.2.10 Sweep Direction
This command sets the direction of the sweep travel. “+” sets incremental sweep, while “-”
sets decremental sweep.
Command:
Response:
<add/SD_s”cr”
>add/SD_s”cr””lf”]
Status Only:
Response:
<add/SD_”cr”
>add/SD_s”cr””lf”]
Where: s = + or - (direction of sweep travel during acquisition).
Note: This command is only valid when Fast Acquisition is enabled. See the “FAM_”
command definition.
G.6.4.2.11 Bit Error Rate Threshold
Command:
Response:
<add/BERT_xxxx”cr”
>add/BERT_xxxx”cr””lf”]
Status Only:
Response:
<add/BERT_”cr”
>add/BERT_xxxx”cr””lf”]
Where: xxxx = NONE or 1E-n (n = 3, 4, 5, 6, 7, or 8 [exponent of threshold]).
Rev. 5
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G.6.4.3 Interface/Doppler Buffer
G.6.4.3.1 Baseband Loopback
Command:
Response:
<add/BBL_xxx”cr”
>add/BBL_xxx”cr””lf”]
Status Only:
Response:
<add/BBL_”cr”
>add/BBL_xxx”cr””lf”]
Where: xxx = ON or OFF.
G.6.4.3.2 Transmit Clock
Command:
Response:
<add/TC_xxx”cr”
>add/TC_xxx”cr””lf”]
Status Only:
Response:
<add/TC_”cr”
>add/TC_xxx”cr””lf”]
Where: xxx = REF (Reference) or EXT (External).
G.6.4.3.3 Receive Clock
Command:
Response:
<add/RC_xxx”cr”
add/RC_xxx”cr””lf”]
Status Only:
Response:
<add/RC_”cr”
>add/RC_xxx”cr””lf”]
Where: xxx = NRM (Normal) or INV (Invert).
G.6.4.3.4 External Reference Frequency
Command:
Response:
<add/ERF_nnnnn”cr”
>add/ERF_nnnnn”cr””lf”]
Status Only:
Response:
<add/ERF_”cr”
>add/ERF_nnnnn”cr””lf”]
Where: nnnnn = 8 to 10000 kHz, in 8 kHz steps.
G–28
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SDM-650B Satellite Modem
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G.6.4.3.5 Interface Reference Clock
Command:
Response:
<add/IRC_xxx”cr”
>add/IRC_xxx”cr””lf”]
Status Only:
Response:
<add/IRC_”cr”
>add/IRC_xxx”cr””lf”]
Where: xxx = TXC (Transmit), RXC (Receive), EXT (External), or INT (Internal).
G.6.4.3.6 Interface Buffer Center
This command centers the Doppler buffer.
Command:
Response:
<add/IBC_”cr”
>add/IBC_”cr””lf”]
G.6.4.3.7 Interface Buffer Depth
This command sets the Doppler buffer depth in bits.
Command:
Response:
<add/IBD_nnnnn”cr”
>add/IBD_nnnnn”cr””lf”]
Status Only:
Response:
<add/IBD_”cr”
>add/IBD_nnnnn”cr””lf”]
Valid buffer depths are 512, 1024, 2048, 4096, 8192, 16384, and 32768.
Rev. 5
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G.6.4.4 System Commands/Responses
G.6.4.4.1 Time of Day
Command:
Response:
<add/TIME_hh:mmxx”cr”
>add/TIME_hh:mmxx”cr””lf”]
Status Only:
Response:
<add/TIME_”cr”
>add/TIME_hh:mmxx”cr””lf”]
Where:
hh = hours.
mm = minutes.
xx = AM or PM.
Example:
Set modem 67 time to 10:45PM.
Command:
Response:
<67/TIME_10:45PM”cr”
>67/TIME_10:45PM”cr””lf”]
G.6.4.4.2 Date
Command:
Response:
<add/DATE_mm/dd/yy”cr”
>add/DATE_mm/dd/yy”cr””lf”]
Status Only:
Response:
<add/DATE_”cr”
>add/DATE_mm/dd/yy”cr””lf”]
Where:
mm = month.
dd = day.
yy = year.
Example:
Set modem 235 date to 11/30/87.
Command:
Response:
G–30
<235/DATE_11/30/87”cr”
>235/DATE_11/30/87”cr””lf”]
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.4.4.3 Remote
Configures the modem for remote operation. The modem will respond to any status request
at any time. However, the modem must be in “Remote Mode” to change configuration
parameters.
Command:
Response:
<add/REM_”cr”
>add/REM_”cr””lf”]
G.6.4.4.4 Clear Stored Faults
This command is used to clear all stored faults logged by the modem.
Command:
Response:
<add/CLSF_”cr”
>add/CLSF_”cr””lf”]
G.6.4.4.5 Modem Operation Mode
This command configures the modem for simplex or duplex operation modes. When
transmit-only mode is selected, receive faults are inhibited. When receive-only mode is
selected, transmit faults are inhibited.
Command:
Response:
<add/MOM_xxxxxxx”cr”
>add/MOM_xxxxxxx”cr””lf”]
Status Only:
Response:
<add/MOM_”cr”
>add/MOM_xxxxxxx”cr””lf”]
Where: xxxxxxx = TX_ONLY, RX_ONLY, or DUPLEX.
Rev. 5
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G.6.4.5 Status Commands/Responses
G.6.4.5.1 Configuration
G.6.4.5.1.1 Modulator/Coder Configuration Status
The Modulator/Coder configuration status command causes a block of data to be returned
by the addressed modem. The block of data reflects the current configuration status of the
Modulator/Coder.
Command:
Response:
G–32
<add/MCS_”cr”
>add/MCS_”cr”
RF_xxx”cr”
MF_nnn.nnnn”cr”
MPO_snn.n”cr”
MOP_snn.n”cr”
MR_nnn_mmmm.m”cr”
AMRA_nnn_mmmm.m”cr”
AMRB_nnn_mmmm.m”cr”
AMRC_nnn_mmmm.m”cr”
AMRD_nnn_mmmm.m”cr”
SE_xxx”cr”
COM_xxx”cr”
DENC_xxx”cr”
AMRV_nnn.mmmm.m”cr””lf”]
RF output (ON/OFF)
Modulator frequency
Modulator Power Offset
Modulator Output Power
Modulator rate
Filter “A” assignment
Filter “B” assignment
Filter “C” assignment
Filter “D” assignment
Scrambler enable (ON/OFF)
Carrier only mode (ON/OFF)
Differential encoder (ON/OFF)
Modulator variable rate assignment
(variable rate option only)
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.4.5.1.2 Modulator/Coder Configuration Program
This command is used by the SMS-658 or SMS-758 M:N protection switch to collect
information that is necessary to configure back-up modems.
Command:
Response:
<add/MCP_”cr”
>add/MCP_”cr”
MF_nnn.nnnn”cr”
MPO_snn.n”cr”
MOP_snn.n”cr”
MR_nnn_mmmm.m”cr”
SE_xxx”cr”
DENC_xxx”cr”
BBL_xxx”cr”
TC_xxx”cr”
ERF_nnnnn”cr”
IRC_xxx”cr”
RF_xx”cr””lf”]
Modulator frequency
Modulator Power Offset
Modulator Output Power
Modulator rate
Scrambler enable (ON/OFF)
Differential encoder (ON/OFF)
Baseband Loopback
Transmit Clock (REF/EXT)
External Reference Frequency (kHz)
Interface Reference Clock source
(TXC/RXC/EXT/INT)
RF output
G.6.4.5.1.3 Demodulator/Decoder Configuration Status
The Demodulator/Decoder configuration status command causes a block of data to be
returned by the addressed modem. The block of data reflects the current configuration of the
demod.
Command:
Response:
<add/DCS_”cr”
>add/DCS_”cr”
DF_nnn.nnnn”cr”
DR_nnn_mmmm.m”cr”
ADRA_nnn_mmmm.m”cr”
ADRB_nnn_mmmm.m”cr”
ADRC_nnn_mmmm.m”cr”
ADRD_nnn_mmmm.m”cr”
DE_xxx”cr”
RC_xxx”cr”
BBL_xxx”cr”
RFL_xxx”cr”
BERT_xxxx”cr”
SR_xxx”cr”
IFL_xxx”cr”
SCF_snnnnn”cr”
SWR_nnnnn”cr”
SD_s”cr”
FAM_xxx”cr”
ADRV_nnn.mmmm.m”cr””lf”]
Demodulator frequency
Demodulator data rate
Filter “A” assignment
Filter “B” assignment
Filter “C” assignment
Filter “D” assignment
Descrambler enable (ON/OFF)
Receive clock (NRM/INV)
Baseband loopback (ON/OFF)
RF loopback (ON/OFF)
BER Threshold
Sweep Reacquisition (seconds)
IF loopback (ON/OFF)
Sweep Center Frequency
Sweep Width
Sweep Direction
Fast Acquisition Mode
Demodulator variable rate assignment
(variable rate option only)
Note: “SCF_”, “SWR_”, and “SD_” responses are returned only when Fast Acquisition is
enabled. See the “FAM_” command definition.
Rev. 5
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G.6.4.5.1.4 Demodulator/Decoder Configuration Program
This command is used by the SMS-658 or SMS-758 M:N protection switch to collect
information that is necessary to configure back-up modems.
Command:
Response:
<add/DCP_”cr”
>add/DCP_”cr”
IFL_xxx”cr”
RFL_xxx”cr”
DF_nnn.nnnn”cr”
DR_nnn_mmmm.m”cr”
DE_xxx”cr”
BERT_xxxx”cr”
SR_xxx”cr”
BBL_xxx”cr”
RC_xxx”cr”
ERF_nnnnn”cr”
IRC_xxx”cr”
IBD_nnnnn”cr”
FAM_xxx”cr”
SCF_snnnnn”cr”
SWR_nnnnn”cr”
SD_s”cr””lf”]
IF loopback (ON/OFF)
RF loopback (ON/OFF)
Demodulator frequency
Demodulator data rate
Descrambler enable (ON/OFF)
BER Threshold
Sweep Reacquisition (seconds)
Baseband Loopback
Receive Clock (INV/NRM)
External Reference Frequency (kHz)
Interface Reference Clock source
(TXC/RXC/EXT/INT)
Interface Buffer Depth (in bits)
Fast Acquisition Mode
Sweep Center Frequency
Sweep Width
Sweep Direction
Note: “SCF_”, “SWR_”, and “SD_” responses are returned only when fast acquisition is
enabled. See the “FAM_” command definition.
G.6.4.5.1.5 Interface Configuration Status
This command causes a block of data to be returned by the addressed modem. The block
reflects the current configuration of the interface.
Command:
Response:
<add/ICS_”cr”
>add/ICS_”cr”
BBL_xxx”cr”
TC_xxx”cr”
RC_xxx”cr”
ERF_nnnnn”cr”
IRC_xxx”cr”
IBD_nnnnn”cr””lf”]
G–34
Base Band Loopback (ON/OFF)
Transmit Clock (REF/EXT)
Receive Clock (INV/NRM)
External Reference Frequency (kHz)
Interface Reference Clock source
(TXC/RXC/EXT/INT)
Interface Buffer Depth (in bits)
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.4.5.2 Modem Faults Status (Summary)
This command returns the current overall fault conditions of the modem.
Command:
Response:
<add/MFS_”cr”
>add/MFS_”cr”
DMD_xxx”cr”
MOD_xxx”cr”
CEQ_xxx”cr””lf”]
Demodulator (FLT/OK)
Modulator (FLT/OK)
Common Equipment (FLT/OK)
G.6.4.5.3 Modulator Status
The modulator status is returned as a block of data which indicates general status
information.
Command:
Response:
<add/MS_”cr”
>add/MS_”cr”
RF_xxx”cr”
MOD_xxx”cr”
AGC_xxx”cr”
SYN_xxx”cr”
BCLK_xxx”cr”
TCLK_xxx”cr”
ICH_xxx”cr”
QCH_xxx”cr”
SFLT_xx”cr””lf”]
RF output (ON/OFF) actual status not config
Module missing or will not program (OK/FLT)
AGC leveled (OK/FLT)
Carrier synthesizer (OK/FLT)
Bit clock (OK/FLT)
Transmit clock (OK/FLT)
I-channel (OK/FLT)
Q-channel (OK/FLT)
Number of stored faults logged (0 to 10)
G.6.4.5.4 Demodulator Status
The demodulator status is returned as a block of data which provides general status
information.
Command:
Response:
Rev. 5
<add/DS_”cr”
>add/DS_”cr”
DMD_xxx”cr”
CD_xxx”cr”
SYN_xxx”cr”
DSCR_xxx”cr”
ICH_xxx”cr”
QCH_xxx”cr”
BCLK_xxx”cr”
BERT_xxx”cr”
RSL_-nn.ndBm”cr”
CSV_snnnnn”cr”
SFLT_xx”cr””lf”]
Demod module (OK/FLT)
Carrier detect (OK/FLT)
Synthesizer lock (OK/FLT)
descrambler (OK/FLT)
I-channel (OK/FLT)
Q-channel (OK/FLT)
bit clock (OK/FLT)
BER threshold (OK/FLT)
Receive Signal Level (level or No Data)
Current Sweep Value
Number of stored faults logged (0 to 10)
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G.6.4.5.5 Common Equipment Status
The common equipment status command causes a block of data to be returned which
indicates the status of the common equipment.
Command:
Response:
<add/CES_”cr”
>add/CES_”cr”
M&C_xxx”cr”
REF_xxx”cr”
OVFL_xxx”cr”
UNFL_xxx”cr”
BAT_xxx”cr”
PS1_xxx”cr”
PS2_xxx”cr”
PS3_xxx”cr”
MODE_xxxxxx”cr”
SW_x.xxx”cr”
SFLT_xx”cr””lf”]
Monitor & Control Module (OK/FLT)
Interface Reference Clock (OK/FLT)
Doppler Buffer overflow (OK/FLT)
Doppler Buffer underflow (OK/FLT)
battery (OK/FLT)
+5V power supply (OK/FLT)
+12V power supply (OK/FLT)
-12V power supply (OK/FLT)
Mode (LOCAL or REMOTE)
Software Version
Number of stored faults logged (0 to 10)
G.6.4.5.6 Bit Error Rate Status
G.6.4.5.6.1 Raw BER
Command:
Response:
<add/RBER_”cr”
>add/RBER_nnnnE-4”cr””lf”]
Where: nnnn = RBER or < 1.0 (lower limit).
Example:
Request Raw BER from modem 123.
Command:
Response:
<123/RBER_”cr”
>123/RBER_152E-4”cr””lf”]
RBER = 0.0152 errors/bit
Note: “No Data” is returned if no carrier is detected (decoder not locked).
G–36
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.4.5.6.2 Corrected BER
Command:
Response:
<add/CBER_”cr”
>add/CBER_nE-m”cr””lf”]
Example:
Request Corrected BER from modem 19.
Command:
Response:
<19/CBER_”cr”
>19/CBER_2E-5”cr””lf”]
CBER = 0.00002 errors/bit
Notes:
1. Corrected BER limits are lower < 1E-8, upper > 01E-3.
2. “No Data” is returned if no carrier is detected (decoder not locked).
G.6.4.5.7 Eb/N0
The Eb/N0 status command causes the Eb/N0 ratio to be returned. Eb/N0 is returned in dB.
Command:
Response:
<add/EBN0_”cr”
>add/EBN0_n.ndB”cr””lf”]
Example:
Request Eb/N0 ratio from modem 2.
Command:
Response:
<2/EBN0_”cr”
>2/EBN0_6.2dB”cr””lf”]
Eb/N0 = 6.2 dB
Notes:
1. Eb/N0 limits are lower < 3.2 dB, upper > 9.7dB.
2. “No Data” is returned if no carrier is detected (decoder not locked).
G.6.4.5.8 Modulator Rate
Command:
Response:
<add/MR_”cr”
>add/MR_nnn_mmmm.m”cr””lf”]
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
Rev. 5
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G.6.4.5.9 Demodulator Rate
Command:
Response:
<add/DR_”cr”
>add/DR_nnn_mmmm.m”cr””lf”]
Where:
nnn = 1/2, 3/4, 7/8, or BP12 (Coder rate).
mmmm.m = 9.6 to 4080.0 (Data rate).
Note: The parameters “nnn_mmmm.m” may be replaced by “N/A” to indicate “no
assignment.”
G.6.4.5.10 Receive Signal Level
Command:
Response:
<add/RSL_”cr”
>add/RSL_-nn.ndBm”cr””lf”]
G.6.4.5.11 Current Sweep Value
This command returns the current sweep value and the decoder lock status.
Command:
Response:
<add/CSV_”cr”
>add/CSV_snnnnn”cr”
CD_xxx”cr””lf”]
Where:
s = + or - (sweep offset direction).
nnnnn = 0 to 25000.
xxx = OK or FLT (decoder lock status OK or FAULT).
G.6.4.5.12 Stored Faults
Information on stored faults is returned when requested. If no stored fault exists for a given
fault number, the words “No Fault” will be returned instead of the normal time/date status
information.
The following symbols are commonly used to define the stored faults status commands:
•
•
•
•
•
•
•
G–38
#
hh
mm
ss
MM
DD
YY
Fault number (0 to 9), “0” is the first fault stored.
Hours in 24-hour format.
Minutes.
Seconds.
Month.
Day.
Year.
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
G.6.4.5.12.1 Modulator Stored Faults
Command:
Response:
<add/MSF_#”cr”
>add/MSF_# hh:mm:ss MM/DD/YY”cr”
MOD_xxx”cr”
Module missing or wont program (OK/FLT)
AGC_xxx”cr”
AGC leveled (OK/FLT)
SYN_xxx”cr”
Carrier synthesizer (OK/FLT)
BCLK_xxx”cr”
Bit clock (OK/FLT)
TCLK_xxx”cr”
Transmit clock (OK/FLT)
ICH_xxx”cr”
I-channel (OK/FLT)
QCH_xxx”cr””lf”]
Q-channel (OK/FLT)
G.6.4.5.12.2 Demodulator Stored Faults
Command:
Response:
<add/DSF_#”cr”
>add/DSF_# hh:mm:ss MM/DD/YY”cr”
DMD_xxx”cr”
Demod module (OK/FLT)
CD_xxx”cr”
Carrier detect (OK/FLT)
SYN_xxx”cr”
Synthesizer lock (OK/FLT)
DSCR_xxx”cr”
descrambler (OK/FLT)
ICH_xxx”cr”
I-channel (OK/FLT)
QCH_xxx”cr”
Q-channel (OK/FLT)
BCLK_xxx”cr”
bit clock (OK/FLT)
BERT_xxx”cr””lf”]
BER threshold (OK/FLT)
G.6.4.5.12.3 Common Equipment Stored Faults
Command:
Response:
Rev. 5
<add/CSF_#”cr”
>add/CSF_# hh:mm:ss MM/DD/YY”cr”
M&C_xxx”cr”
Monitor & Control Module (OK/FLT)
REF_xxx”cr”
Interface Reference Clock (OK/FLT)
OVFL_xxx”cr”
Doppler Buffer overflow (OK/FLT)
UNFL_xxx”cr”
Doppler Buffer underflow (OK/FLT)
BAT_xxx”cr”
battery (OK/FLT)
PS1_xxx”cr”
+5 volt power supply (OK/FLT)
PS2_xxx”cr”
+12 volt power supply (OK/FLT)
PS3_xxx”cr””lf”]
-12 volt power supply (OK/FLT)
G–39
Trojan Interface
SDM-650B Satellite Modem
G.6.4.5.13 Bulk Consolidated Status
This command causes bulk modem status to be returned. To reduce the length of the
response, message parameter data are returned without identifiers. However, parameter
identification can be determined by order of return. Each status parameter is terminated with
a “,” (comma), except for the last parameter which has the standard message termination
sequence (”cr””lf”]). For standardization reasons, some parameters may not be
implemented but will retain the terminating “,” (comma). Most of the data returned is
formatted the same way as the single command status request (refer to the appropriate
portions of this document in preceding sections).
Command:
Response:
<add/BCS_”cr”
>add/BCS_p1,p2,p3, . . . pn”cr””lf”]
Where: pn =
Parameter 1 (p1): Modulator RF output ON/OFF.
p1 = n, where “n” is “0” to indicate off or “1” to indicate on.
Parameter 2 (p2): Modulator IF frequency.
p2 = nnnn.nnnn, where “nnnn.nnnn” is the modulator IF frequency in MHz.
Parameter 3 (p3): Modulator output power level.
p3 = snn.n, where “snn.n” is the transmitter output power level in dBm.
Parameter 4 (p4): Modulator rate currently programmed.
p4 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 5 (p5): Modulator filter A assignment.
p5 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 6 (p6): Modulator filter B assignment.
p6 = nnn_mmmm.m, where “nnn” is the code rate and “mmmm.m” is the data rate in
kbit/s.
Parameter 7 (p7): Modulator filter C assignment.
p7 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 8 (p8): Modulator filter D assignment.
p8 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 9 (p9): Scrambler enable ON/OFF.
p9 = n, where “n” is “0” to indicate off or “1” to indicate on.
Parameter 10 (p10): Carrier only mode ON/OFF.
p10 = n, where “n” is “0” to indicate off or “1” to indicate on.
Parameter 11 (p11): Differential encoder enable ON/OFF.
p11 = n, where “n” is “0” to indicate off or “1” to indicate on.
Parameter 12 (p12): Transmit clock source (Reference/External).
p12 = n, where “n” is “0” or “1” (“0” = REF, “1” = EXT).
Parameter 13 (p13): Demodulator IF frequency.
p13 = nnnn.nnnn, where “nnnn.nnnn” is the demodulator IF frequency in MHz.
Parameter 14 (p14): Demodulator rate currently programmed.
p14 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
G–40
Rev. 5
SDM-650B Satellite Modem
(See Note)
(See Note)
(See Note)
Trojan Interface
Parameter 15 (p15): Demodulator filter A assignment.
p15 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 16 (p16): Demodulator filter B assignment.
p16 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 17 (p17): Demodulator filter C assignment.
p17 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 18 (p18): Demodulator filter D assignment.
p18 = nnn_mmmm.m, where “nnn” is the code rate, and “mmmm.m” is the data rate in
kbit/s.
Parameter 19 (p19): Descrambler enable ON/OFF.
p19 = n, where “n” is “0” to indicate off or “1” to indicate on.
Parameter 20 (p20): Receive clock (Invert/Normal).
p20 = n, where “n” is “0” or “1” (“0” = NRM, “1” = INV).
Parameter 21 (p21): Baseband loopback ON/OFF.
p21 = n, where “n” is “0” to indicate off, or “1” to indicate on.
Parameter 22 (p22): RF loopback ON/OFF.
p22 = n, where “n” is “0” to indicate off, or “1” to indicate on.
Parameter 23 (p23): Not implemented.
p23 = “,”.
Parameter 24 (p24): BER threshold.
p24 = nnnn, where “nnnn” is the currently programmed BER threshold in the same
format as the single command “BERT_”.
Parameter 25 (p25): Sweep Reacquisition.
p25 = nnn, where “nnn” is the reacquisition parameter in seconds.
Parameter 26 (p26): IF loopback ON/OFF.
p26 = n, where “n” is “0” to indicate off, or “1” to indicate on.
Parameter 27 (p27): MODEM REMOTE/LOCAL mode.
p27 = n, where “n” is “0” to indicate local or “1” to indicate remote.
Parameter 28 (p28): Sweep center programmed.
p28 = snnnnn, where “s” is “+” or “-”, and “nnnnn” is the sweep center currently
programmed.
Parameter 29 (p29): Sweep width range.
p29 = nnnnn, where “nnnnn” is in the range of 0 to 50000 Hz.
Parameter 30 (p30): Sweep direction.
p30 = n, where “n” is “+” for positive or “-” for negative sweep direction.
Parameter 31 (p31): External Reference Frequency.
p31 = nnnnn, where “nnnnn” is the external reference frequency in kHz.
Parameter 32 (p32): Interface Reference Clock.
p31 = n, where “n” is “0”, “1”, “2”, or “3” (“0” = TXC, “1” = RXC, “2” = EXT, “3” =
INT).
Parameter 33 (p33): Interface Buffer Depth.
p33 = nnnnn, where “nnnnn” is “512”, ”1024”, ”2048”, ”4096”, ”8192”, ”16384”, or
”32768”.
Note: Parameters 28, 29, and 30 are only returned when fast acquisition is enabled. See the
“FAM_” command definition.
Rev. 5
G–41
Trojan Interface
SDM-650B Satellite Modem
G.6.4.5.14 Bulk Consolidated Analog Status
This command is similar to the “BCS_” command, but returns MODEM analog parameters.
Command:
Response:
<add/BCAS_”cr”
>add/BCAS_p1,p2,p3, . . . pn”cr””lf”]
Where: pn =
Parameter 1 (p1): Receive signal level.
p1 = -nn, where “nn” is the value of the receive signal level in dBm.
Parameter 2 (p2): Raw BER.
p2 = nnnnE-4, where “nnnn” is the raw bit errors in 10000 bits.
Parameter 3 (p3): Corrected BER.
p3 = nE-e, where “n” is the mantissa and “e” is exponent (power of 10).
Parameter 4 (p4): EB/N0.
p4 = n.n, where “n.n” is Eb/N0 in dB.
Note: Parameters 1 through 4 are dependent on carrier acquisition. If the decoder is not
locked, empty data blocks are returned (,,,).
G.6.4.5.15 Bulk Consolidated Status Faults
This command causes all modem fault status to be returned. To reduce the length of the
response, fault status is embedded into the bit structure of the characters that are returned.
Faults are indicated by a binary 1 in the designated bit position.
Command:
Response:
<add/BCSF_”cr”
>add/BCSF_abcdef”cr””lf”]
Character “a”: Modulator fault status character 1.
Bit 6 = 1 always.
Bit 5 = Modulator fault.
Bit 4 = RF output status, actual not programmed status
(1 = on, 0 = off).
Bit 3 through Bit 0 = Binary representation (0 to 10) of the
number of modulator stored faults.
Character “b”: Modulator fault status character 2.
Bit 6 = 1 always.
Bit 5 = AGC fault.
Bit 4 = Modulator RF synthesizer fault.
Bit 3 = Bit clock fault.
Bit 2 = Transmit clock fault.
Bit 1 = I-channel fault.
Bit 0 = Q-channel fault.
G–42
Rev. 5
SDM-650B Satellite Modem
Trojan Interface
Character “c”: Demodulator fault status character 1.
Bit 6 = 1 always.
Bit 5 = Demodulator fault.
Bit 4 = Carrier detect status (0 for decoder lock).
Bit 3 through Bit 0 = Binary representation (0 to 10) of the
number of demodulator stored faults.
Character “d”: Demodulator fault status character 2.
Bit 6 = 1 always.
Bit 5 = Demodulator RF synthesizer fault.
Bit 4 = Descrambler fault.
Bit 3 = I-channel fault.
Bit 2 = Q-channel fault.
Bit 1 = Bit clock fault.
Bit 0 = BER threshold fault.
Character “e”: Common equipment fault status character 1.
Bit 6 = 1 always.
Bit 5 = M&C fault.
Bit 4 = Reference fault.
Bit 3 through Bit 0 = Binary representation (0 to 10) of the
number of common equipment stored faults.
Character “f”: Common equipment fault status character 2.
Bit 6 = 1 always.
Bit 5 = Battery fault.
Bit 4 = +5 volt fault.
Bit 3 = +12 volt fault.
Bit 2 = -12 volt fault.
Bit 1 = Overflow fault.
Bit 0 = Underflow fault.
G.6.4.5.16 Change Status
This command indicates that a change has or has not occurred on either the BCS_ or the
BCSF_ response since the last BCS_ or BCSF_ poll.
Command:
Response:
<add/CS_”cr”
>add/CS_x”cr””lf”]
Where: x =
“@” = no change since last CS_ poll.
“A” = BCS_ response has changed since last CS_ poll.
“B” = BCSF_ response has changed since last CS_ poll.
“C” = Both responses have changed since last CS_ poll.
Rev. 5
G–43
Trojan Interface
SDM-650B Satellite Modem
G.6.4.5.17 Equipment Type
This command returns the equipment model number and M&C firmware version number.
Command:
Response:
<add/ET_”cr”
>add/ET_SDM650S_x.xxx”cr””lf”]
Where: x.xxx = M&C firmware version.
G–44
Rev. 5
Glossary
The following is a list of acronyms and abbreviations that may be found in this manual.
Acronym/
Abbreviation
Ω
16QAM
8PSK
A
A/D
AC
ADC
ADJ
ADMA
ADPCM
AFC
AGC
AIS
AM
AMI
AOC
APM
ASC
ASCII
ASK
ASYNC
AUPC
AUX 1
AVC
BB
BCD
BER
BER CONT
bit/s
BPSK
Rev. 5
Definition
Ohms
16 Quadrature Amplitude Modulation
8 Phase Shift Keying
Ampere
Analog to Digital
Alternating Current
Analog to Digital Converter
Adjust
Amplitude Domain Multiple Access
Adaptive Differential Pulse Code Modulation
Automatic Frequency Control
Automatic Gain Control
Alarm Indication Signal
Amplitude Modulation
Alternate Mark Inversion
Automatic Offset Control
Amplitude Phase Modulation
Add-Select-Compare
American Standard Code for Information Interchange
Amplitude Shift Keying
Asynchronous
Automatic Uplink Power Control
Auxiliary 1
Automatic Volume Control
Baseband
Binary Coded Decimal
Bit Error Rate
BIT Error Rate Continuous
Bits per second
Bi-Phase Shift Keying
Draft
g–1
Glossary
SDM-650B Satellite Modem
BTU
BW
BWR
C
C/N
C/No
CCITT
CDMA
CH
CHNL
CIC
CL
CLK
CLNA
CLR
CMOS
Coax
Codec
COM
CPFSK
CPSK
CPU
cr
CRC
CRT
CS
CSC
CSMA
CTS
CU
CW
D&I
D/A
D/C
DAC
DAMA
dB
dB/Hz
dBc
dBm
dBm0
dBW
DC
DCE
DCPSK
DDO
DDS
Demod
DEMUX
DET
DM
DPCM
DPSK
DSP
DSR
g–2
British Thermal Unit
Backward Alarm or Bandwidth
Bandwidth Ratio
Celsius
Carrier-to-Noise Ratio
Carrier-to-Noise Density Ratio
International Telephone and Telegraph Consultative Committee
Code Division Multiple Access
Channel
Channel
Common Interface Circuit
Carrier Loss
Clock
C-band LNA
Clear
Complementary Metal Oxide Semiconductor
Coaxial
Coder/Decoder
Common
Continuous-Phase Frequency Shift Keying
Coherent Phase Shift Keying
Central Processing Unit
Carriage Return
Cyclic Redundancy Check
Cathode Ray Tube
Clear to Send
Comstream Compatible
Carrier Sense Multiple Access
Clear to Send
Channel Unit
Continuous Wave
Drop and Insert
Digital-to-Analog
Down Converter
Digital-to-Analog Converter
Demand Assignment Multiple Access
Decibels
Decibels/Hertz (unit of carrier-to-noise density ratio)
Decibels referred to carrier
Decibels referred to 1.0 milliwatt
The signal magnitude in dBm referenced to the nominal level at that
point
Decibels referred to 1.0 watt
Direct Current
Data Circuit Terminating Equipment
Differentially Coherent Phase Shift Keying
Drop Data Output
Direct Digital Synthesis
Demodulator
Demultiplexer
Detector
Data Mode
Differential Pulse Code Modulation
Differential Phase Shift Keying
Digital Signal Processing
Data Signal Rate
Draft
Rev. 5
SDM-650B Satellite Modem
DTE
E&M
Eb/N0
ECL
EDP
EEPROM
EFD
EIA
EMC
EMF
EPROM
ESC
ESD
EXC
EXT
FDC
FDMA
FEC
FET
FFSK
FIFO
Flt
FM
FPGA
FS
FSK
FW
GHz
GND
HI STAB
HPA
Hz
I&Q
I/O
IBS
IC
IDI
IDR
IESS
IF
INMARSAT
INTELSAT
ISD
k
KΩ
kbit/s
kHz
ks/s
kW
LAN
LCD
LED
lf
LNA
LO
LSB
Rev. 5
Glossary
Data Terminal Equipment
Ear and Mouth
Bit Energy-to-Noise Ratio
Emitter Coupled Logic
Electronic Data Processing
Electrically-Erasable Programmable Read-Only Memory
EFData Compatible
Electronic Industries Association
Electro-Magnetic Compatibility
Electromotive Force
Erasable Read-Only Memory
Engineering Service Circuit or Engineering Service Channel
Electrostatic Discharge
External Clock
External Reference Clock
Fairchild Data Compatible
Frequency Division Multiple Access
Forward Error Correction
Field Effect Transistor
Fast Frequency Shift Keying
First in/First Out
Fault
Frequency Modulation
Field Programmable Gate Array
Frame Sync
Frequency Shift Keying
Firmware
Gigahertz (109 hertz)
Ground
High Stability
High Power Amplifier
Hertz (cycle per second)
In-Phase and Quadrature
Input/Output
INTELSAT Business Services
Integrated Circuit
Insert Data Input
Intermediate Data Rate
INTELSAT Earth Station Standards
Intermediate Frequency
International Maritime Satellite Organization
International Telecommunications Satellite Organization
Insert Send Data
Kilo (103)
Kilo-ohms
Kilobits per second (103 bits per second)
Kilohertz (103 Hertz)
Kilosymbols Per Second (103 symbols per second)
Kilowatt (103 Watts)
Local Area Network
Liquid Crystal Display
Light-Emitting Diode
Line Feed
Low Noise Amplifier
Local Oscillator
Least Significant Bit
Draft
g–3
Glossary
SDM-650B Satellite Modem
LSI
m
M&C
mA
Max
Mbit/s
MC
MFS
MHz
Min
Mod
MOP
MPC
ms
Ms/s
MSB
MUX
n
N/A
NACK
NC
NO
NRZ
ns
OQPSK
OSC
p
P-P
P/AR
PAL
PC
PCB
PCM
PECL
pF
PK
PLL
PN
PPM
PS
PSK
PWB
PWR
QAM
QPSK
RAM
RD
REF
RF
RLSD
RMA
ROM
RR
RS
RT
RTS
g–4
Large Scale Integration (semiconductors)
Mille (10-3)
Monitor and Control
Milliamperes
Maximum
Megabits per second
Monitor and Control
Multiframe Sync
Megahertz (106 Hertz)
Minimum or Minute
Modulator
Modulated Output Power
Microprocessor Controller
Millisecond (10-3 second)
Megasymbols per second
Most Significant Bit
Multiplexer
Nano (10-9)
Not Applicable
Negative Acknowledgment
No Connection or Normally Closed
Normally Open
Non-Return to Zero (code)
Nanosecond (10-9 second)
Offset Quadrature Phase Shift Keying
Oscillator
Pico (10-12)
Peak-to-Peak
Peak to Average Ratio
Programmable Array Logic
Printed Circuit
Printed Circuit Board
Pulse Code Modulation
Positive Emitter Coupled Logic
PicoFarads (10-12 Farads)
Peak
Phase-Locked Loop
Pseudo-Noise
Parts Per Million
Power Supply
Phase Shift Keying
Printed Wiring Board
Power
Quadrature Amplitude Modulation
Quadrature Phase Shift Keying
Random Access Memory
Receive Data
Reference
Radio Frequency
Receive Line Signal Detect
Return Material Authorization
Read-Only Memory
Receiver Ready
Ready to Send
Receive Timing
Request to Send
Draft
Rev. 5
SDM-650B Satellite Modem
Glossary
RX
RXCLK
RXD
RZ
s
S/N
SCPC
SCR
SCT
SCTE
SD
SFS
SMS
SN
SSB
SSPA
ST
SW
SYNC
TB
TCXO
TDMA
TEMP
TERR
TP
TT
TTL
TX
TXCLK
TXD
TXO
U/C
UART
UHF
UNK
US
UW
V
VAC
VCO
VCXO
VDC
VSWR
W
WG
Rev. 5
Receive (Receiver)
Receive Clock
Receive Data
Return-to-Zero
Second
Signal-to-Noise Ratio
Single Channel Per Carrier
Serial Clock Receive
Serial Clock Transmit
Serial Clock Transmit External
Send Data
Subframe Sync
Satellite Multiservice System
Signal-to-Noise Ratio
Single-sideband
Solid State Power Amplifier
Send Timing
Switch
Synchronize
Terminal Block
Temperature-Compensated Crystal Oscillator
Time Division Multiple Access
Temperature
Terrestrial
Test Point
Terminal Timing
Transistor-Transistor Logic
Transmit (Transmitter)
Transmit Clock
Transmit Data
TX Octet
Up converter
Universal Asynchronous Receiver/Transmitter
Ultra-high Frequency
Unknown
United States
Unique Word
Volts
Volts, Alternating Current
Voltage-Controlled Oscillator
Voltage-Controlled Crystal Oscillator
Volts, Direct Current
Voltage Standing Wave Ratio
Watt
Waveguide
Draft
g–5
Glossary
SDM-650B Satellite Modem
This page is intentionally left blank.
g–6
Draft
Rev. 5
METRIC CONVERSIONS
Units of Length
Unit
Centimeter
Inch
Foot
Yard
Mile
Meter
Kilometer
Millimeter
1 centimeter
—
0.3937
0.03281
0.01094
6.214 x 10-6
0.01
—
—
1 inch
2.540
—
0.08333
0.2778
1.578 x 10-5
0.254
—
25.4
1 foot
30.480
12.0
—
0.3333
1.893 x 10-4
0.3048
—
—
1 yard
91.44
36.0
3.0
—
5.679 x 10-4
0.9144
—
—
1 meter
100.0
39.37
3.281
1.094
6.214 x 10-4
—
—
—
1 mile
1.609 x 105
6.336 x 104
5.280 x 103
1.760 x 103
—
1.609 x 103
1.609
—
1 mm
—
0.03937
—
—
—
—
—
—
1 kilometer
—
—
—
—
0.621
—
—
—
Temperature Conversions
° Fahrenheit
Unit
100
F = (C * 1.8) + 32
(water boils)
273.1
—
-459.6° Fahrenheit
C = (F - 32) * 0.555
(water freezes)
—
212° Fahrenheit
Formulas
0
—
32° Fahrenheit
° Centigrade
(absolute 0)
Units of Weight
Gram
Ounce
Avoirdupois
Ounce
Troy
Pound
Avoir.
Pound
Troy
Kilogram
—
0.03527
0.03215
0.002205
0.002679
0.001
1 oz. avoir.
28.35
—
0.9115
0.0625
0.07595
0.02835
1 oz. troy
31.10
1.097
—
0.06857
0.08333
0.03110
1 lb. avoir.
453.6
16.0
14.58
—
1.215
0.4536
1 lb. Troy
373.2
13.17
12.0
0.8229
—
0.3732
1 kilogram
1.0 x 103
35.27
32.15
2.205
2.679
—
Unit
1 gram
2114 WEST 7TH STREET TEMPE ARIZONA 85281 USA
480 • 333 • 2200 PHONE
480 • 333 • 2161 FAX
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