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Common Analysis and Display Functions
R&S
®
FSW
491
User Manual 1173.9411.02 ─ 19
Fig. 7-14: n dB down marker function
The following marker function results are displayed:
Table 7-4: n dB down marker function results
Label
Description
M1
Current position and level of marker 1
ndB
Offset value (n dB down)
ndB down Bw /
PWid
Determined bandwidth or pulse width (zero span) at the offset
Q-factor
Quality factor of the determined bandwidth (characteristic of damping or resonance)
T1, T2
Current position and level of the temporary markers
If the required position for the temporary markers cannot be determined uniquely, for
example due to noise, dashes are displayed as a result.
7.4.1.10
Measuring the Power in a Channel (Band)
When you want to determine the noise power in a transmission channel, you could use
a noise marker and multiply the result with the channel bandwidth. However, the
results would only be accurate for flat noise.
Band power markers allow you to measure the integrated power for a defined span
(band) around a marker (similar to ACP measurements). By default, 5 % of the current
span is used. The span is indicated by limit lines in the diagram. The results can be
displayed either as a power (dBm) or density (dBm/Hz) value and are indicated in the
marker table for each band power marker.
Marker Usage