6
Demonstration 4:
Spot frequency measurement
Spot frequency measurement inves-
tigates the phase noise behavior at a
specific offset frequency by providing
the time domain view.
With the signal tracking function
on (the defaulted state), the carrier
frequency drift can be observed.
Figure 5. Spot frequency measurement provides carrier frequency drift view and phase noise change
versus time in a specific offset
Instructions
Keystrokes
On the X-Series signal analyzer:
Start Spot frequency
[Meas] {Power Stat CCDF}
Set the signal analyzer with a carrier
frequency of 1 GHz
[Trace/Detector] {Store Ref Trace}
Set the spot offset frequency to 10 kHz
[Trace/Detector] {Ref Trace On}
On the MXG
Set the incremental frequency at 10 Hz
per step
[FREQ] [Incr Set] [10] {kHz}, then [↑]
or [↓] to manually adjust the carrier
frequency drift by 10 kHz/step
On the X-Series Phase Noise mode:
Adjust the signal analyzer’s Y-axis scale
according to the 10 Hz/step set on the MXG.
Manually adjust the RF carrier frequency
from the output of the signal generator up or
down by 10 Hz steps to see the stair shaped
trace in the delta frequency pane.
Press the third button from the power
switch at the analyzer’s front panel to
activate the “Delta Freq” pane (with
a light green frame), then [AMPTD]
{Scale/Div} [10] {Hz}
View the spot frequency phase noise along
with the numerical results of the SSB phase
noise table
[View/Display] {Numerical}
Turn the signal tracking off
[FREQ Channel] {Signal Tracking Off}
