To Next Page

To Previous Page

Measurements and Results

R&S

FSW

141User Manual 1173.9411.02 ─ 43

is equal to the frequency spacing, the spectrum display shows a level drop of 3 dB pre-

cisely in the center of the two signals. Decreasing the resolution bandwidth makes the

level drop larger, which thus makes the individual signals clearer.

In this measurement example we will analyze two signals with a level of -30 dBm each

and a frequency spacing of 30 kHz.

Figure 7-5: Test setup

Table 7-3: Signal generator settings (e.g. R&S SMW)

Level Frequency

Signal generator 1 -30 dBm 128,00 MHz

Signal generator 2 -30 dBm 128,03 MHz

1. Select [PRESET] to reset the instrument.

2. Set the center frequency to 128.015

MHz.

3. Set the frequency span to 300

kHz.

4. Set the resolution bandwidth to 30

kHz and the video bandwidth to 1

kHz.

Note: Larger video bandwidths. The video bandwidth is set to 1 kHz in order to

make the level drop in the center of the two signals clearly visible. At larger video

bandwidths, the video voltage that results from envelope detection is not suffi-

ciently suppressed. This produces additional voltages, which are visible in the

trace, in the transition area between the two signals.

Basic Measurements

R&S FSW Series User Manual

Questions and Answers: