R&S FSW Series, Руководство пользователя

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Measurements and Results
R&S
®
FSW
146 User Manual 1173.9411.02 ─ 43
3. Set the frequency span to 0 Hz or select "Zero Span".
4. Set the sweep time to 2.5 ms .
5. Set the reference level to 6 dBm and the display range to linear ([AMPT] > "Scale
Config" > "Scaling": "Linear Percent").
6. Define triggering in response to the AF signal using the video trigger to produce a
static image.
a) Press the [TRIG] key.
b) Select "Video".
c) Set the "Trg/Gate Level" to
50% .
The trigger level is displayed as a horizontal line across the entire measurement
diagram. The R&S
FSW displays the 1 kHz AF signal as a static image in zero
span.
Figure 7-12: Measurement of the AF signal of a carrier that is AM-modulated with 1 kHz
7. Activate the internal AM demodulator to output the audio signal.
a) Press the [MKR FUNC] key.
b) Select "Marker Demodulation".
The R&S FSW automatically switches on the AM audio demodulator. A 1 kHz
tone can be heard over headset (via the PHONES connector). If necessary,
use the volume control to turn up the volume.
7.1.6 Measurement Examples in Zero Span
For radio transmission systems that use the TDMA method (for example, GSM), trans-
mission quality is determined not only by spectral characteristics but also by character-
istics in zero span. A timeslot is assigned to each user since several users share the
Basic Measurements