Residual FM

(E8257D Option H42 and E8257N and E8663D Option HE3 Only)

Residual FM measures the unwanted frequency variation in the CW signal of the DUT.

There are two sets of procedures depending on the PSG-D model being tested:

Select from the links below depending on the model number of the DUT.

For E8257D and E8257N PSG-D models, .

Required Test Equipment

Test Equipment

Recommended Models

Alternative Models

Spectrum Analyzer

N9030B Opt 5xx1 with N9063EM0E Analog Demodulation Measurement application

N9030A2 Opt 5xx1 with N9063EM0E Analog Demodulation Measurement application

E444xA3 Opt 233 Measuring Receiver Personality
  1. Select any option of PXA spectrum analyzer (503, 508, 513, 526, 543, 544, 550) that has a maximum frequency greater than or equal to the maximum frequency of the unit under test. The N9030A/B Option 550 is required for units with Option 567. The N9030A/B Option 550 frequency range is adequate for all PSG-D frequency configurations.
  2. To use the PXA N9030A with N9063EM0E Analog Demodulation Measurement application functionality above 3.5 GHz, the N9030A must be upgraded with either Option MTU or TES. Refer to the section in the Required Test Equipment topic.
  3. Select any model of PSA spectrum analyzer (E4440A, E4443A,E4445A, E4446A, E4447A, E4448A) that has a maximum frequency greater than or equal to the maximum frequency of the unit under test. An E4448A is required for units with Option 567. The E4448A frequency range is adequate for all PSG-D frequency configurations.

 

Connections and Setup Procedures

  • All test equipment requires a 30 minute warmup period to ensure accurate performance.

  • In the following test setup, cables are designated as solid lines and direct connections are designated as dashed lines.

  • This performance test has a smart connection feature.

  1. Connect all test equipment as shown.

  2. Connect GPIB cables to all GPIB-controlled test equipment.

  3. While performing this performance test, follow all instructions on the controller display.

Spectrum Analyzer Test Setup

Setup for Residual FM

 

For E8663D Option HE3, .

 

For the E8663D Option HE3 PSG-D, a Phase Noise Test System is used to measure the Residual FM by taking a single sideband phase noise measurement of the DUT. The area under the phase noise plot between 300 Hz and 3 kHz or 50 Hz and 15 kHz is the Residual FM. If the DUT fails, it may be due to the DUT phase noise specifications being better than the reference source. (For information on performing a three-source measurement, click here.)

Required Test Equipment

Test Equipment

Recommended Models

Alternate Model(s)

Phase Noise System

N5511A Options 540, CH21

  1. CH2 is not required but recommended for future capability.

E5505A
E5504A/B
E5503A/B

Reference Source

E8663D Opt HY2

  1. Option HE3 is also allowed since it includes Option HY2.

 

Connections and Setup Procedures for a Manual Residual FM Measurement

There are two sets of procedures depending on the model of the phase noise test system used:

Select from the links below according to the phase noise test system being used.

N5511A PNTS, .

 

 

  1. Connect all test equipment as shown.

  2. Connect GPIB cables to all GPIB-controlled test equipment.

  3. Preset all test equipment and the DUT.

  4. Change the following parameters in the N5510A PNTS user interface:

    1. Select the View pull-down menu.

    2. Select Display Preferences and un-check the Spurs box.

    3. Select OK to close Display Preferences.

    4. Select the System pull-down menu and select Server Hardware Connections.

    5. Select or ensure the following:

      1. Test Set has Keysight M9550A selected.

      2. FFT Analyzer has Keysight M9551A selected.

    6. Select Close to close Server Hardware Connections.

    7. Select the Define pull-down menu, select Measurement, and select the following settings:
       

Parameter

Setting

 

 

Type and Range Tab

Measurement Type

Absolute phase noise (using a phase locked loop)

Measurement Method

Fast

Start Offset Resolution Expansion

10

Channel Setup

Single

Start Offset Frequency

290 Hz (must be < 300 Hz)

Stop Offset Frequency

3.1 kHz (must be > 3 kHz)

FFT Analyzer Minimum Number of Trace Averages

4

RBW %

1.96 (1024 point FFT)

FFT Overlap %

75

FFT Window Type

Flat Top

 

 

Sources Tab

Carrier Source Frequency

Obtain tested frequencies from the TME data entry form.

Carrier Source Power

+10 dBm

Detector Input Frequency

Same as Carrier Source Frequency

Reference Source Power

+15 dBm to 3 GHz

+10 dBm > 3 GHz

VCO Nominal Tune Constant

0.1 ppm x carrier source frequency

VCO Tune Range

5 Volts

VCO Input Resistance

50 Ω

Center Voltage

0 V

 

 

Cal Tab

Phase Detector Constant

Derive detector constant from measured beat note

VCO Tune Constant

Measure VCO Tune Constant

Verify calculated phase lock loop suppression

Blank

 

 

Block Diagram Tab

Carrier Source

Manual

Reference Source

Model number of reference source

Phase Detector

Automatic Detector Selection

Test Set Tune Voltage Output

Front Panel

Test Set Tune Voltage Destination

Reference Source

VCO Tune Mode

DCFM

 

 

Test Set Tab

LNA Low Pass Filter

Internal — Selected

Auto — Checked

LNA Gain

Auto Gain — Selected

Minimum Auto Gain — 14 dB

PLL Integrator Attenuation

0 dB

Use Channel #2

Unchecked

 

 

Graph Tab

Title

User specified

Graph Type

Spectral Density of Phase Fluctuations (dB/Hz)

X Scale minimum

Same as start offset frequency

X Scale maximum

Same as stop offset frequency

Y Scale maximum

0 dB/Hz

Y Scale minimum

–170 dB/Hz

Normalize Trace Data

1 Hz bandwidth

Making the Measurement

  1. Set the DUT frequency to the first carrier frequency and power in the TME data entry form.

  2. Set the DUT RF Output to On.

  3. Perform a phase noise measurement.

  4. Place markers on the Sφ(f) plot at 300 Hz and 3 kHz.

    Note that the E8663D HE3 also tests with the markers set at 50 Hz and 15 kHz. Use a start offset of 49 Hz and a stop offset of 15 kHz.

    When specifying a marker offset, the marker will be set to the closest frequency on the graph as indicated in the following table:

    Nominal Offset

    Actual Offset

    50 Hz

    49.918 Hz

    300 Hz

    299.54 Hz

    3 kHz

    3.0034 kHz

    15 kHz

    14.974 kHz

     

  5. Click on the Analyze pull-down menu and select Trace Integration.

  6. Use the following settings:

    Parameter

    Actual Offset

    Data Type

    Snu(f) (Spectral density of frequency fluctuations)

    CCIT Weighting

    checked

    Start Offset

    Same as start offset frequency

    Stop Offset

    Same as stop offset frequency

    Data to Integrate

    Noise

     

  7. Click on the Integrate field and read the Residual FM value from under the Value of definite integral.

  8. Enter the Residual FM value into the TME user interface for Residual FM and compare it to the specification.

  9. Repeat steps 1 through 8 for each frequency test point through 3 GHz.

  10. For test points > 3 GHz, a connection change is required.

    1. Connect the UUT RF Output to the 1.2 GHz to 40 GHz Sig/RF Input of the M9550A Phase Detector module in the N5511A PNTS.

    2. Connect the Reference Source Output to the 1.2 GHz to 40 GHz Ref/LO Input of the M9550A Phase Detector module in the N5511A PNTS.

    3. Repeat steps 1 through 8 for each frequency test point > 3 GHz.

 

For E5505A, E5504A/B, and E5503A/B legacy phase noise test system, .

  1. Connect all test equipment as shown.

  2. Connect GPIB cables to all GPIB-controlled test equipment.

  3. Preset all test equipment and the DUT.

  4. Set the DUT to the following settings:

    DUT Settings

    Manual Procedure

    SNR mode On

    Preset the DUT sets the SNR mode On.

    To do this, perform the following steps:

    1. Press Amplitude > More > More > Optimize S/N Off On and select On.
    2. Press Frequency > More > RF Path and select Low Phase Noise.

    3. Press Frequency > More > Low Pass Filter Below 2 GHz and select On.

     

    Modulation mode Off

    Press Mod On/Off > select Off.

     

  5. In the E5505A Phase Noise System user interface, change the following parameters:

    1. Select the View pull-down menu.

    2. Select Display Preferences and un-check the Spurs box.

    3. Select OK to close Display Preferences.

    4. Select the System pull-down menu and select Server Hardware Connections.

    5. Select or ensure that the FFT Analyzer has NI PCI6111-1, 11 PCI20428W-1, or 89410A selected.

    6. Select Close to close Server Hardware Connections.

    7. Select the Define pull-down menu, select Measurement, and select the following settings:

       

      Table 1: E8663D Option HE3 Test Frequency and Power

      Frequency (MHz)

      DUT Power (dBm)

      10

      +10

      20

      +10

      50

      +10

      100

      +10

      200

      +10

      500

      +10

      1000

      +10

      2000

      +10

      3000

      +10

     

    Parameter

    Setting

     

     

    Type and Range Tab

     

    Measurement Type

    Absolute phase noise (using a phase locked loop)

    Start Offset Frequency

    10 Hz

    Stop Offset Frequency

    100 kHz

    FFT Averages

    4

    FFT Quality

    High Resolution

    Swept Quality

    Normal

     

     

    Sources Tab

     

    Carrier Source Connected

    Test Set

    Carrier Source Frequency

    See Table 1 above

    Carrier Source Power

    See Table 1 above

    Detector Input Frequency

    Same as carrier source frequency

    Reference Source Power

    +16 dBm to 250 MHz, +10 dBm > 250 MHz

    Nominal Tune Constant

    1 ppm x carrier source frequency

    Nominal Tune Range

    1 Volt

    Input Resistance

    50 ohms

    Center Voltage

    0 Volt

     

     

    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

    E8257D

    Phase Detector Mode

    Automatic Detector Selection

    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 Gain

    PLL Integrator Attenuation

    0 dB

     

     

    Graph Tab

     

    Title

    User specific

    Graph Type

    Spectral Density of Phase Fluctuations (dB/Hz)

    X Scale minimum

    Same as start offset frequency

    X Scale maximum

    Same as start offset frequency

    Y Scale maximum

    0 dBm

    Y Scale minimum

    -170 dBm

    Normalize Trace Data

    1 Hz bandwidth

Making the Measurement

  1. Set the DUT frequency to the first carrier frequency and power in Table 1 above.

  2. Ensure the Optimize φ Noise is set to Optimize φ Noise Offset < 150 kHz (Mode 1). To do this, select Frequency > More > More > Optimize φ Noise.

  3. Set the DUT RF Output to On.

  4. Perform a phase noise measurement.

    1. If using a release of the phase noise measurement software older than A.04.05.0001, when the window appears, ensure the Input Impedance on the Reference Source’s Ext 1 Input is set to 50 Ohms. To do this, select FM/ φM > More > Ext Impedance and select 50 Ohm.

  5. Place markers on the Sphi (f) plot at 300 Hz and 3 kHz, or 50 Hz and 15 kHz according to the Bandwidth tested.

  6. Left mouse click on the Analyze pull-down menu and select Trace Integration.

    Setup

    Parameter

    Setting

    Data Type

    Snu(f) (Spectral Density of Frquency Fluctuations)

    Start Offset

    300 Hz (for 300 Hz to 3 kHz Bandwidth)

    50 Hz (for 50 Hz to 15 kHz Bandwidth)

    Stop Offset

    3 kHz (for 300 Hz to 3 kHz Bandwidth)

    15 kHz (for 50 Hz to 15 kHz Bandwidth)

    CCITT Weighting

    Unchecked

    Data to Integrate

    Noise and Spurs

    Checkmarked

     

  7. Click on the Integrate field and read the Residual FM value from under the Value of definite integral.

  8. Enter the Residual FM value into the TME user interface for Residual FM and compare it to the specification.

  9. Make two integrations for 300 Hz to 3 kHz Bandwidth and 50 Hz to 15 kHz Bandwidth.

  10. Continue to the next carrier setup and repeat the measurement. If the next carrier is > 1 GHz, then connect the reference generator signal to the 1.2 GHz to 26.5 GHz N5500A Reference input.

    If a failure occurs, it may not be due to the signal generator. For some test conditions, the signal generator specifications are better than the reference source specifications. If a failure occurs, a three-source measurement should be performed at this carrier frequency to identify a true failure. (For information on performing a three-source measurement, click here.)

 

Entering the Data

The measurement data must be entered into the following form displayed on-screen when the test is run. Shown below is the input form for the E8663D Option HE3.

Residual FM column — The measured Residual FM value from the phase noise test set system.

In Case of Difficulty

If this performance test fails, perform the following steps in order:

  1. Check the equipment setup (see above). If the setup is incorrect, make the necessary corrections and rerun the Performance Test.

  2. If this test fails with the equipment set up 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 Keysight Website.

  3. If you cannot correct the problem using the troubleshooting procedures in the Service Guide, obtain service from Keysight Technologies. Refer to Contacting Keysight Technologies.