Getting Started
R&S
®
FSPN
69
User Manual 1179.4363.02 ─ 01
Tip:
You can define
in the "Integration Ranges" tab of
the "Noise Config" dialog box.
3.4.2.3
Baseband Noise Measurement
Baseband Noise measurements measure the noise characteristics of a DUT over an
absolute frequency span (not relative to carrier).
You can use either the RF input for these measurements, or the baseband input. The
baseband input is DC coupled and extend the lower frequency range to 1
mHz (the
lowest supported frequency on the RF input is 1
MHz). Using the baseband input, you
can, for example, test the voltage supply of DC sources.
Test setup
DUT
R&S FSPN
RF / BB*
V
aux
V
tune
V
supply
required connections
optional connections
* = See text below for instructions on how to use the baseband input.
How to measure baseband noise at the RF input
For baseband noise measurements on the RF input, proceed as follows.
1. Connect the DUT to the RF input.
2. Perform a [PRESET].
The application automatically starts a continuous measurement and measures the
noise characteristics of the DUT in the default frequency range.
3. Select the "Baseband Noise" measurement via the [MEAS] key.
4. 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.
Tip:
Integrated measurement results. Note that the "PM", "FM" and "Jitter" results
are always "0" for baseband noise measurements.
How to measure baseband noise at the baseband input
For baseband noise measurements on the baseband input, proceed as follows.
1. Connect the DUT to the baseband input.
Trying Out the Instrument
