This manual test verifies that the signal generator's single-sideband phase noise meets specifications.
During this test, a phase noise system is used to measure the single-sideband phase noise of the signal generator. An Agilent 8665B or PSG signal generator (reference source) is used to produce reference frequencies for 500 MHz, 1 GHz, 2 GHz, 3 GHz, and 4 GHz. The phase noise is measured at 20 kHz offsets and compared to specifications.
|
Instrument |
Critical Specifications for This Test |
Recommended Model(s) |
|
Phase Noise System |
Input: APC 3.5 (m) |
Agilent E5502B Option 001 |
|
Reference Source |
Output: Type-N (f), |
Agilent 8665B with Option 004 or |
|
Cable |
APC 3.5 (m) to (m) |
Agilent 8120-4921 |
|
Cable |
Type-N (m) to (m) |
Agilent
11500C |
|
Cable |
BNC (m) to (m) |
Agilent 8120-1840 BNC (m) to (m)
cable |
|
Adapter |
BNC Tee (m) (f) (f) |
Agilent E9625A |
|
Adapter |
2.4 mm (f) to APC 3.5 (m) |
Agilent 11901D |
|
Adapter |
APC 3.5 (f) to (f) |
Agilent 1250-1749 |
|
|
All test equipment requires a 30 minute warm-up period to ensure accurate
performance. |
Setup with a carrier frequency of 500 MHz

Connect all test equipment as shown.
Connect GPIB cables to all GPIB-controlled test equipment.
Preset all test equipment and the signal generator.
Connect the 8665B/E82XXX RF output to the 70420A 50 kHz to 1600 MHz reference input.
Connect the 70420A Tune Voltage Output to the 8665B FM input or the E82XXX Ext 1 input.
|
Frequency (MHz) |
DUT Power (dBm) |
Reference Power (dBm) |
|
500 |
14 |
12 |
|
1000 |
14 |
12 |
|
2000 |
10 |
5 |
|
3000 |
10 |
5 |
|
4000 |
10 |
5 |
In the Agilent E5502B Option 001 Phase Noise System user interface, change the following parameters:
Select the View pull down menu.
Select Display Preferences and clear the Spurs box.
Select OK to close Display Preferences.
From the System pull down menu, select Server Hardware Connections.
Ensure the correct FFT Analyzer is selected, either the 11 PCI20428W-1 or the 89410A.
Connect the signal generator's RF OUTPUT to the 70420A signal input.
From the Define pull down menu, select Measurement, and set the following:
|
Parameter |
Setting |
|
|
|
|
Type and Range Tab |
|
|
Measurement Type |
Absolute phase noise |
|
Start Offset Frequency |
1 Hz |
|
Stop Offset Frequency |
1 MHz |
|
FFT Averages |
4 |
|
FFT Quality |
Normal |
|
Swept Quality |
Normal |
|
|
|
|
Sources Tab |
|
|
Carrier Source Connected |
Test Set |
|
Carrier Source Frequency |
See Table 1. |
|
Carrier Source Power |
See Table 1. |
|
Detector Input Frequency |
See Table 1. |
|
Reference Source Power |
See Table 1. |
|
VCO Tune Constant |
10,000 Hz/Volt |
|
VCO Tune Range |
5 volts |
|
VCO Input Resistance |
50 ohms for PSG, 600 ohms for 8665B |
|
|
|
|
Cal Tab |
|
|
Measure Phase Detector Constant |
Checkmark |
|
Measure VCO Tune Constant |
Checkmark |
|
Verify calculated phase lock loop suppression |
Blank |
|
Phase Lock Loop Suppression |
Use theoretical value. |
|
|
|
|
Block Diagram Tab |
|
|
Carrier Source |
Manual |
|
Down Converter |
None |
|
Reference Source |
E82XXA/C/D with Option UNJ or UNR or UNX or 8665B with Option 004 |
|
Phase Detector Mode |
Automatic |
|
Test Set Tune Voltage Destination |
Reference Source |
|
VCO Tune Mode |
DCFM |
|
|
|
|
Test Set Tab |
|
|
Input Attenuation |
0 dB |
|
LNA Low Pass Filter |
Auto |
|
LNA Gain |
Auto |
|
PLL Integrator Attenuation |
0 dB |
|
|
|
|
Downconverter Tab |
|
|
Input Attenuation |
Auto |
|
IF Gain |
Auto |
|
Microwave/Millimeter Band |
Microwave (0 &endash; 26.5 GHz) |
|
Reference Chain Reference |
10 MHz |
|
External Tune Enable |
Blank |
|
|
|
|
Graph Tab |
|
|
Title |
User specific |
|
Graph Type |
Single-sideband phase noise (dBc/Hz) |
|
X Scale minimum |
1 Hz |
|
X Scale maximum |
1E+6 |
|
Y Scale maximum |
0 |
|
Y Scale minimum |
|
|
Normalize Trace Data |
1 Hz bandwidth |
Making the Measurement
Set the signal generator frequency to the first carrier frequency and power in Table 1.
Set the RF Output to on.
Perform a phase noise measurement.
From the Measure pull down menu, select New Measurement.
Place a marker at 20 kHz offset.
Compare the marker amplitude value to the following specifications:
|
Offset from Carrier (dBc/Hz) |
|
|
Carrier Frequency |
20 kHz |
|
500 MHz |
< |
|
1 GHz |
< |
|
2 GHz |
< |
|
3 GHz |
< |
|
4 GHz |
< |
Print out a phase noise plot.
Set the signal generator frequency to the next carrier frequency and power in Table 1.
In the Agilent E5502B Option 001 Phase Noise System user interface make the following changes:
|
Sources Tab |
|
|
Carrier Source Frequency |
See Table 1. |
|
Carrier Source Power |
See Table 1. |
|
Detector Input Frequency |
See Table 1. |
|
Reference Source Power |
See Table 1. |
If the next frequency is greater than 1 GHz, connect the Reference Source RF Output to the 70420A 1.2 GHz to 26.5 GHz RF Input.
Repeat steps 2 through 9 for the remaining frequencies in Table 1.
Check the equipment setup (see above). If the setup is incorrect, make the necessary corrections and rerun the Performance Test.
If this test fails with the equipment setup properly, refer to the troubleshooting section of the signal generator's service guide. If you do not have a printed copy of the service guide (Option OBW), one is available either on the CD-ROM that came with your signal generator shipment, or on the Agilent Website.
If you cannot correct the problem using the troubleshooting procedures in the Service Guide,.refer to Contacting Agilent Technologies for service.