Attachment

40

Frequency converters

Figure 25. 85309 LO/IF distribution unit and 85320A/B mixer modules

The 85309A LO/IF distribution unit and the 85320A/B mixers downconvert a microwave signal to an IF signal that can be measured by the PNA. The distributed frequency converter uses external mixers for microwave downconversion. These mixers can be located directly at the antenna under test. The frequency of operation depends upon the frequency range of the external mixers selected.

Features

• Allows mixers to be located at the antenna under test, minimizing RF cable loss

• Allows fundamental mixing to 18 GHz for best sensitivity

• Provides best rejection of unwanted spurious signals

Description

The 85309A LO/IF distribution unit contains LO signal amplifiers, which amplify LO drive power through RF cables to the mixers. The high output power allows the mixers to be located more than seven meters from the 85309A. Since the 85309A uses a separate LO amplifier for each channel, channel-to-channel isolation of 100 dB is achieved, minimizing signal leakage from the reference to the test channel and improving the accuracy of the measurement. There are also IF amplifiers located in the 85309A, which serve as a preamplifier for the receiver, reducing the overall system noise figure significantly.

A leveling detector in the reference mixer is used to provide the proper LO drive to the mixers. It is important to use equal length cables to both the reference and test mixers to ensure the same cable loss, and provide the same LO drive power to both mixers.

An internal filter in the reference IF channel is designed to pass frequencies below

20 MHz. This allows the proper IF signal to be passed for both PNA Option 014 and PNA

Option H11.

Specifications

Nominal channel performance

Table 7. 85309A specifications

Frequency range

Power output (LO Ports)

Output power channel tracking

LO Input return loss

0.3

LO Output return loss

IF channel small signal gain 21

19

2

9

7

Maximum Conditions

18

1

GHz

± 2

25 dBm dB dB dB dB 20 MHz,

–35 dBm input

1. Maximum measurement frequency is dependent on the mixers selected. Mixer selection allows for measurements to 50 GHz, however fundamental mixing is limited to 18 GHz.

2. See Figure 26 for mixer specific power levels.

Absolute maximum ratings

LO input power (CW)

Ref. chan. IF input power (CW)

Ref. channel detector input

Pos. Z/blanking input

Storage temperature

Operating temperature

+23 dBm

+13 dBm

± 20 VDC

± 10 VDC

–40 to +75 ºC

0 to +55 ºC

Remote mixer distances

Mixers require a certain LO drive power level; the output power of the 85309A LO/IF distribution unit and the RF loss of the cables will determine the maximum allowable cable lengths. Maximum cable lengths can be calculated using the following equations:

Cable (source to 85309A) length (meters) = (P

OUT meter @ frequency) source – P

IN

85309A)/(cable loss/

Cable (85309A to mixers) length (meters) = (P

OUT meter @ frequency)

85309A – P

IN mixer)/(cable loss/

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The following diagram shows the power levels for the various mixer configurations.

L.O./I.F. Dist. unit

85309A

LO in

Pin =

6 to 10 dBm

LO out

Po =

16 dBm

(0.3 - 3 GHz)

ALC

85320A/B

Opt H20

Dwn conv. mixers

Ref chan.

Pmxr =

8 to 16 dBm

Test chan.

8 dB max.

0.3 - 3 GHz

L.O./I.F. Dist. unit

LO in

85309A

LO out

Pin =

0 to 6 dBm

Po =

19 dBm

(2 -18 GHz)

85320A/B

Dwn conv. mixers

ALC

11 dB max.

Pmxr =

8 to 16 dBm

Ref chan.

Test chan.

2 - 18 GHz

1. Mixers are operated in the 3rd harmonic mode.

L.O./I.F. Dist. unit

85309A

LO in

Pin =

0 to 6 dBm

LO out

Po =

20.4 dBm

(2 - 8.85 GHz)

85320A/B

Dwn conv. mixers

ALC

12.4 dB max.

Pmxr =

8 to 16 dBm

Ref chan.

Test chan.

6 - 26.5 GHz

1

L.O./I.F. Dist. unit

85309A

LO in

Pin =

0 to 6 dBm

LO out

Po =

19 dBm

(2 - 18 GHz)

85320A/B

Opt H50

Dwn conv. mixers

ALC

Pmxr =

12 to 17 dBm

Ref chan.

Test chan.

7 dB max.

2 - 18 GHz

L.O./I.F. Dist. unit

85309A

LO in

Pin =

0 to 6 dBm

LO out

Po =

19 dBm

(6 - 16.7 GHz)

ALC

85320A/B

Opt H50

Dwn conv. mixers

Ref chan.

Pmxr =

12 to 17 dBm

Test chan.

7 dB max.

18 - 50 GHz

1

Figure 26. 85309A external mixer configurations

85309A options

Option 001

Option 002 adds a second test channel; provides a total of two test channels and one reference channel. adds two additional test channels; provides a total of three test channels and one reference channel.

Option 908

Option 913 rack mount kit without handles. rack mount kit with handles.

Option 910 additional manual.

Option W30 extended return-to-Agilent warranty.

Option W31 extended on-site warranty.

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Special options

Occasionally an application requires locating the mixers at a distance greater than is possible with a standard 85309A. Greater distances require additional LO output power from the 85309A. Several special options that increase the output power of the 85309A are available. Refer to the 85309A-H30 section in this document.

Other information

Connectors

Power consumption type-N female

Environmental operating conditions: 0 to 55 °C

Non-operating conditions –40 to 75 °C; 5 to 90% relative humidity, non-condensing.

47.5 to 66 Hz, 100-120 or 220-240 VAC (±10%); 125 VA maximum.

Weight

Size

15.5 kg (34 lb)

460 mm (18.1 in) W x 133 mm (5.25 in) H x 533 mm (21 in) D

Ref antenna

IF

3 dB

85320B

LO x

LO DET

IF

RF input to mixers = –24 dBm (.1 dB compression point)

Conversion gain from RF input of mixers to IF output of 85309A

∼ 10.5 dB

LO input to 85309A should be

∼ 0 to +6 dBm

LO input ot mixers should be

∼ +11 to +14 dBm

Agilent 85309A

LO/IF unit

AT3

Slope pad

LO input amp

LO input

J1

A17 A11

Power divider

Ref LO amp

A12

A1

Detector voltage display

J2 J5 J4

Ref IF amp

A14

A2

ALC assembly

A10

J10

Ref IF

J6

Pos

Z blank

AT4

Slope pad

<--ALC feedback

A13

Test LO amp

A16 diplexer

J3

J8

J7

A15

J9

Test IF

Test IF amp

Input Freq.

Max input (.1dB)

Front

A, B, R1, R2 20 Mhz –14 dBm

Rear H11

A, B, R1, R2 8.33 Mhz –27 dBm

Test antenna

LO/IF

85320A

Diplexer

Rear panel jumper

H11 inputs

A

Attenuators

3 dB

Setup/cal program

A

B

E836X PNA 080, 081, 014, H11

* H11 damage level is – 20 dBm

Figure 27. 85309A LO/IF distribution unit block diagram

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44

85309A-H30, -H31 and -H32 high-power LO/IF distribution units

The 85309A-H30, -H31, and -H32 are the high-power versions of the 85309A LO/IF distribution unit. H30, H31, and H32 designate special high-power options for the 85309A:

85309A-H30: high output power; one test channel and one reference channel.

85309A-H31: high output power; two test channels and one reference channel.

85309A-H32: high output power; three test channels and one reference channel.

Specifications

Table 8. 85309A-H30, -H31 and –H32 specifications

Frequency range

Power output

Power output

Power output

Power output

0.3

+21.5

+22.75

+24.75

+22.75

> +24.5

1

> +25

1

> +25

1

> +27

1

> +30

1

> +26

2

> +25

1

> +28

1

18

Output power channel tracking

LO input return loss 9

± 2

LO output return loss 7

IF channel small signal gain

21 25

1. Typical measurement on 85309A-H32 test channel #3.

2. Typical measurement on 85309A-H32 test channel #3, 6 to 9 GHz, 0 dBm input.

Absolute maximum ratings

LO input power (CW) +23 dBm

Ref. channel IF input power (CW) +13 dBm

Ref. channel detector Input

Pos. Z/blanking input

±20 VDC

±10 VDC

Storage temperature

Operating temperature

–40 to 85 °C

0 to 50 °C

Other information

Connectors: type-N female

GHz dBm dBm dBm dBm dB dB dB dB

0.3 to 0.5 GHz, 0dBm input

+6 dBm Input

0.5 to 3 GHz, 0dBm input

+6 dBm Input

3 to 6.2 GHz, 0dBm input

+6 dBm Input

6.2 to 18 GHz, 0dBm input

+6 dBm Input

0.3 to 18 GHz 0 or

+6 dBm input

0.3 to 18 GHz 0 or

+6 dBm input

0.3 to 18 GHz 0 or

+6 dBm input

20 MHz, –35 dBm input

1. Mixers are operated in the 3rd Harmonic Mode.

The following diagram shows the power levels for the various mixer configurations.

L.O./I.F. Dist. unit

85309A

LO in

Pin =

6 to 10 dBm

LO out

Po =

21.5 dBm

(0.3 - 3 GHz)

Opt H3x

ALC

85320A/B

Opt H20

Dwn conv. mixers

Ref chan.

Pmxr =

8 to 16 dBm

Test chan.

13.5 dB max.

0.3 - 3 GHz

L.O./I.F. Dist. unit

LO in

85309A

LO out

Pin =

0 to 6 dBm Po =

22.5 dBm

(2 -18 GHz)

Opt H3x

ALC

85320A/B

Dwn conv. mixers

Pmxr =

8 to 16 dBm

Ref chan.

Test chan.

14.5 dB max.

2 - 18 GHz

L.O./I.F. Dist. unit

85309A

LO in

Pin =

0 to 6 dBm

LO out

Po =

22.5 dBm

(2 - 8.85 GHz)

Opt H3x

ALC

85320A/B

Dwn conv. mixers

14.5 dB max.

Pmxr =

8 to 16 dBm

Ref chan.

Test chan.

6 - 26.5 GHz

1

L.O./I.F. Dist. unit

85309A

LO in

Pin =

0 to 6 dBm

LO out

Po =

22.5 dBm

Opt H3x

(2 - 18 GHz)

ALC

85320A/B

Opt H50

Dwn conv. mixers

10.5 dB max.

Pmxr =

12 to 17 dBm

Ref chan.

Test chan.

2 - 18 GHz

L.O./I.F. Dist. unit

85309A

LO in

Pin =

0 to 6 dBm

LO out

Po =

22.5 dBm

Opt H3x

(2 - 16.7 GHz)

ALC

85320A/B

Opt H50

Dwn conv. mixers

Ref chan.

Pmxr =

12 to 17 dBm

Test chan.

10.5 dB max.

18 - 50 GHz

1

Figure 28. 85309A Option H30, 31, 32 external mixer configurations

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46

85320A/B mixer modules

Figure 29. 85320A/B mixer module

The 85320A/B, 85320A/B-H20, and 85320A/B-H50 mixer modules are designed for use with the 85309A LO/IF distribution unit. Each antenna range should have one reference mixer (B model numbers) and one to three text mixers (A model numbers). In conjunction with the 85309A, the mixers serve to downconvert microwave frequencies to an IF signal for measurement by the PNA network analyzer.

Features

The mixer modules are broadband with various operating frequencies which are designated by option number. The 85320A/B-H20 are low frequency modules that operate from 300 MHz to 3 GHz in fundamental mixing mode. The 85320A/B operate in fundamental mixing mode from 1 to 18 GHz and third-harmonic mixing can be used for the frequency range of 6 to 26.5 GHz. The 85320A/B-H50 operates in fundamental mixing mode from 2 to 18 GHz and in third-harmonic mode from 18 to 50 GHz. Fundamental mixing mode provides the lowest conversion loss and best sensitivity.

85320A test mixers

The 85320A, 85320A-H20 and 85320A-H50 contain a diplexer that combines the LO input and IF output onto a single coaxial connector, which is useful for systems using a rotary joint.

Mixer

IF

3 dB attenuator RF input

Connector type varies with option number

LO

Diplexer

Type-N

connector

LO input

IF output

Figure 30. 85320A test mixer

85320B reference mixers

The 85320B, 85320B-H20, 85320B-H50 contain a leveling coupler/detector that provides a leveling signal to the 85309A LO/IF distribution unit, ensuring leveled LO drive power to the mixer.

IF

Mixer

LO

3 dB attenuator RF input

Connector type varies with option number

IF out

LO in

Det. out

Type-N female connector

Figure 31. 85320B reference mixer

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48

Specifications

Frequency range

85320A/B-H20

85320A/B

85320A-H50

85320A-H50

Fundamental mixing mode

Fundamental mixing mode

Fundamental mixing mode

Third-harmonic mode

Maximum input levels

Maximum DC voltage at input

Maximum signal level at RF or LO inputs

300 MHz to 3 GHz

1 to 18 GHz

2 to 18 GHz

18 to 50 GHz

10 volts

+20 dBm (Option H20)

+26 dBm (standard, Option H50)

Table 9. LO signal power

LO frequency

85320A/B-H20

0.3 to 3 GHz

85320A/B

1 to 18 GHz

85320A/B-H50

2 to 18 GHz

Minimum power Typical power Maximum power

+8 dBm

+7.5 dBm

+10 dBm

+11 dBm

+16 dBm

+16 dBm

+12 dBm +14 dBm +17 dBm

Table 10. Conversion loss

Frequency range LO harmonic

85320A/B-H20

300 MHz to 3 GHz 1

85320A/B

1 to 2 GHz 1

2 to 3 GHz

3 to 5 GHz

1

1

5 to 18 GHz

6 to 8 GHz

8 to 16 GHz

16 to 26.5 GHz

1

3

3

3

85320A/B-H50

2 to 18 GHz

18 to 50 GHz

1

3

–10 dB

18.0 dB

12.0 dB

11.0 dB

14.7 dB

23.8 dB

26.5 dB

28.5 dB

–12 dB

–28 dB

Typical loss Maximum loss

–14 dB

22 dB

16 dB

15 dB

17 dB

26 dB

28 dB

33 dB

Connector types

RF input

All other connectors type-N female (Option H20)

3.5 mm male (standard)

2.4 mm male (Option H50) type-N female

Environmental characteristics

Operating conditions

Non-operating conditions ing.

0 to +55 °C

0 to +45 °C (Option H50)

–40 to +75 °C; 5 to 90% relative humidity, non-condens-

Size

85320A (excluding connectors) 97 mm (3.8 in) W x 122 mm (4.8 in) L x 34 mm (1.3 in) D

(Option H20, H50)

83 mm (3.25 in) W x 122 mm (4.8 in) L x 33 mm (1.3 in) D

(standard)

85320B (excluding connectors) 97 mm (3.8 in) W x 186 mm (7.3 in) L x 31 mm (1.2 in) D

(Option H20, H50)

92 mm (3.6 in) W x 185 mm (7.3 in) L x 25 mm (1.0 in) D

Weight

85320A-H20

85320A

85320A-H50

85320B-H20

85320B

85320B-H50

700 g (1.52 lb)

615 g (1.35 lb)

794 g (1.75 lb)

840 g (1.85 lb)

840 g (1.85 lb)

1021 g (2.25 lb)

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