Keysight N9068A, Демонстрационное руководство

Страница: 4 / 8

4
Demonstration 2:
Log plot measurement
The log plot is the most-frequently
used presentation of a DUT’s phase
noise performance. It measures
single-sideband phase noise (in dBc/
Hz) versus offset frequencies from the
carrier on a logarithmic scale.
View the entire phase noise behavior
across decades of offset frequencies.
Adjust the number of decades by
selecting the appropriate start and
stop offsets.
Perform trace smoothing with the
user-adjustable smoothing segment
length and view it superimposed with
the raw data trace.
Figure 3. Log plot phase noise with a smoothed trace and decade table turned on
Instructions Keystrokes
On the X-Series in Phase Noise mode:
View log plot [Meas] {Log Plot}
Set the signal analyzer with a carrier fre-
quency of 1 GHz and an amplitude reference
level of 0 dBm
[FREQ Channel] {Carrie Freq} [1]
{GHz}; [AMPTD Y Scale] {Ref Value}
[0] {dBm}
Set the start offset to 100 Hz and stop
offset to 100 MHz and restart the log plot
measurement
[SPAN X Scale] {Start Offset} [100]
{Hz}; {Stop Offset} [100] {MHz}, then
[Restart]
Turn the Decade table on, so that you can
have both graphic and tabular presentations
[Meas Setup] {More 1 of 2},
{Decade Table on}