Getting Started
R&S
®
FSPN
67
User Manual 1179.4363.02 ─ 01
DUT
R&S FSPN
RF
V
aux
V
tune
V
supply
required connections
optional connections
Figure 3-5: Typical test setup for basic noise measurements
Measuring phase noise
1. Perform a [PRESET].
The application automatically starts a continuous measurement.
First, it searches for a carrier signal (see
been found, it measures the noise characteristics of the DUT in the default mea-
surement (or frequency offset) range.
If no carrier could be found, a corresponding error message is displayed in the sta-
tus bar below the diagram.
2. You can stop the measurement (to analyze the measurement data in detail) with
the [RUN SGL] or [RUN CONT] key; [RUN SGL] performs one more measurement,
then stops, [RUN CONT] stops immediately.
By default, two traces are displayed: the first trace shows the smoothed data with-
out spurs, the second trace the raw data including spurs.
Measuring amplitude noise
The test setup is the same as shown above.
The default phase noise trace shows the phase noise characteristics of the DUT. In
addition, you can also display the amplitude noise characteristics (or both together).
1. Enter the "Overview" dialog box and, from there, enter the "Analysis" dialog box.
2. Select the vertical "Trace" tab, and then the horizontal "Traces" tab.
3. For any trace, select "AM Noise" from the "Result" dropdown menu.
4. Start a new measurement to determine the AM noise of the DUT.
(The "Phase + AM Noise" menu item displays the sum of phase and amplitude
noise.)
Tip:
If you'd like to view both results separately at the same time, open two phase
noise diagrams, one that shows the phase noise, the other showing the AM noise
and perform a measurement.
Trying Out the Instrument
