R&S FSH
Spectrum Analyzer Mode
Performing Spectrum Measurements
Operating Manual 1309.6275.12 - 14
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2.1.2.1 Selecting a Standard
If you need to perform measurements that are conform to a telecommunications
standard, you can activate one of the predefined standards that are already stored in
the R&S FSH memory. However, you can create new configurations to perform
measurements on other standards as well.
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Press the MEAS key.
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Press the "Standard" softkey.
The R&S FSH opens a dialog box to select the standard.
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Select one of the available standards.
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Confirm the selection with the "Select" softkey.
The R&S FSH loads the configuration of the selected standard. It automatically
sets the optimal span, resolution bandwidth, video bandwidth, sweep time and
detector for the standard.
You can create and edit standards with the R&S FSH4View software and transfer them
to the R&S FSH via the USB or the LAN interface. The number of standards the
R&S FSH can store in its memory depends on the number of other data sets stored on
the R&S FSH.
For more information see "
Saving and Loading Instrument Settings and Measurement
If you make changes to the settings or create datasets, note that
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the span is always coupled to the channel bandwidth. Changes to either of those
automatically adjust the other (= 5 x channel bandwidth).
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the resolution bandwidth should be between 1 % and 4 % of the channel
bandwidth. This ensures that the occupied bandwidth is measured with high
accuracy.
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the video bandwidth must be at least three times the resolution bandwidth. This
prevents incorrect results due to the compression of signal peaks by the video
filter.
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you use the RMS detector if possible. This ensures that the power measurement is
always correct irrespective of the waveform being investigated.
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the sweep time must be set so that the result is stable. If you increase the sweep
time, the R&S FSH also increases the integration time for the RMS detector and
thus ensures more stable measured values.
2.1.2.2 Setting the Reference Level
The reference level is the power level that the R&S FSH expects at the RF input. When
selecting the reference level, make sure that you do not overload the R&S FSH by
applying a signal whose power exeeds the maximum reference level.
As the power is measured with a small resolution bandwidth compared to the signal
bandwidth, it is still possible to overload the R&S FSH, even if the trace is within the
measurement diagram.
