Trying Out the Instrument
R&S
®
FSWP
56
Getting Started 1177.5756.02 ─ 13
5.2.2
The Phase Noise Measurement
Test setup
Connect the DUT via cable to the RF input of the R&S
FSWP as shown in the
illustration.
DUT
R&S FSWP
RF
V
aux
V
tune
V
supply
required connections
optional connections
Figure 5-1: 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
one has been found, it measures the noise characteristics of the DUT in the
default measurement (or frequency offset) range.
If no carrier could be found, a corresponding error message is displayed in the
status 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
without 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.
Measurements
