Special Considerations For Phase Noise Measurements - Agilent Technologies 89410A Operator's Manual

1.
Select PM demodulation:
Press [
Instrument Mode
], [ ], [
demod type Analog Demodulation
Mode
Press [
demodulation setup
2.
Select PSD measurement data:
Press [
Measurement Data
3.
Set the x-axis scale to log:
Press [ ], [
Data Format
4.
Turn on averaging:
Press [ ], [
Average average on
5.
Run (or start) the measurement and scale the results:
Press [ ] to make the measurement.
Meas Restart
Press [ ] to scale the trace data.
Auto Scale
The display should now appear as shown below.
Phase Noise Plot

Special Considerations for phase noise measurements:

l
This is a measurement of S
the phase noise. L
(f)
l
RBW must be small enough so that the low frequency portion of the log X-axis is
valid. RBW should be less than the start frequency.
l
Note that the span in demodulation mode is one-half the span of the instrument.
], [ ] (with option AYH, press [
Analog Demodulation
], [ ]).
Return
], [ ], [ ].
ch1 result PM
], [ ] ([ ] for a 2-channel analyzer).
PSD PSD ch1
].
x-axis log
], [ ], 100, [
num averages
which is defined as the power in both sidebands of
0
is typically defined as the power in one sideband.
Measuring Phase Noise
Instrument
fast avg on
], [ ].
enter
2-3