Rohde & Schwarz R&S FSP Series, Operating Manual

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R&S FSP Instrument Functions
Analyzer Mode
4.48 Operating Manual 1164.4556.12 - 06
The rms detector supplies the power of the signal independent of the waveform. For
this effect the root mean square of all sampled level values is formed during the
sweep of a pixel. The sweep time thus determines the number of averaged values
and with increasing sweep time better averaging is obtained. The rms detector is
thus an alternative for averaging over several sweeps (see TRACE AVERAGE).
Since the video bandwidth must be at least 10 times the resolution bandwidth
(RBW) to ensure that video filtering does not invalidate the rms values of the signal,
this ratio is set automatically upon activating the detector.
Remote command:
DET RMS
DETECTOR
AVERAGE
The DETECTOR AVERAGE softkey activates the average detector.
In contrast to the rms detector, the average detector supplies the linear average of
all sampled level values during the sweep of a pixel.
The same relations as for the rms detector apply (see above).
Remote command:
DET AVER
DETECTOR
QPK
The DETECTOR QPK softkey activates the quasipeak detector.
This detector evaluates the sampled level values during the sweep of a pixel like an
analog voltmeter.
On switching the quasipeak detector on the video bandwidth is automatically set to
10*RBW so as to exclude the influence of the video filter on the signal evaluation.
With an active quasipeak detector only the resolution bandwidths 200 Hz, 9 kHz and
120 kHz are available.
Remote command:
DET QPE
4.5.8.2 Mathematical Functions for Traces
TRACE MATH
The TRACE MATH softkey opens a submenu in which the difference between the
selected trace to trace 1 is calculated. The softkey is highlighted if a math function is
activated.
T1-T2->T1 |
T1-T3->T1
The T1-T2 and T1-T3 softkeys subtract the corresponding traces. The result dis-
played is referred to the zero point defined by TRACE POSITION .
To indicate that the trace has been obtained by subtraction, the difference "1 - 2" or
"1 - 3" is indicated on the trace info of trace 1 and in the
TRACE main menu the
TRACE MATH softkey is highlighted.
Remote command:
CALC:MATH (TRACE1–TRACE2)
CALC:MATH (TRACE1–TRACE3)
T1-T2->T1 |
T1-T3->T1
TRACE POSITION
TRACE MATH OFF