Rohde & Schwarz R&S FSP Series, Operating Manual

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R&S FSP Instrument Functions
Analyzer Mode
4.46 Operating Manual 1164.4556.12 - 06
Average detector
The average detector forms the average value of the measured values within a
pixel.
To this effect, R&S FSP uses the linear voltage after envelope detection. The sam-
pled linear values are summed up and the sum is divided by the number of samples
(= linear average value). For logarithmic display the logarithm is formed from the
average value. For linear display the average value is displayed. Each pixel thus
corresponds to the average of the measured values summed up in the pixel.
The average detector supplies the average value of the signal irrespective of the
waveform (CW carrier, modulated carrier, white noise or impulsive signal).
Quasipeak detector
The quasipeak detector resembles the behavior of an analog voltmeter by evaluat-
ing the measured values in a pixel.
The quasipeak detector is especially designed for the requirements of EMC mea-
surements and is used for evaluating pulse-shaped spurious.
DETECTOR
The DETECTOR softkey opens a submenu for selecting the detector for the selected
trace. The softkey is highlighted if the detector is not selected with AUTO SELECT .
The detector can be selected independently for each trace. The AUTO SELECT
mode selects the optimum detector for each display mode of the trace (Clear/Write,
Max Hold or Min Hold).
The softkeys for the detectors are mutually exclusive selection keys.
During a frequency sweep, R&S FSP increments the 1st local oscillator in steps
that are smaller than approximately 1/10 of the bandwidth. This is to ensure that
the signal level is correctly measured. For narrow bandwidths and wide frequency
spans a very large number of measured values is thus obtained. The number of
frequency steps, however, always is a multiple of 625 (= number of pixels that can
be displayed). With the sample detector selected, only every n
th
value is dis-
played. The value of n depends on the number of measured values, i.e. on the fre-
quency span, the resolution bandwidth and the measurement rate.
AUTO SELECT
DETECTOR AUTO PEAK
DETECTOR MAX PEAK
DETECTOR MIN PEAK
DETECTOR SAMPLE
DETECTOR RMS
DETECTOR AVERAGE
DETECTOR QPK