Common Analysis and Display Functions
R&S
®
ESW
201User Manual 1177.6298.02 ─ 08
The Quasipeak Detector
The quasipeak detector displays the maximum value weighted to CISPR 16-1-1 that
was detected during the measurement.
Depending on the selected frequency, the R&S ESW automatically selects the detec-
tors and IF bandwidths defined for bands A, B and C/D listed in the following table:
Band A Band B Band C/D
Frequency range < 150 kHz 150 kHz to 30 MHz > 30 MHz
Resolution bandwidth 200 Hz 9 kHz 120 kHz
Charge time constant 45 ms 1 ms 1 ms
Discharge time constant 500 ms 160 ms 550 ms
Time constant of the
mechanical device
160 ms 160 ms 100 ms
The coupling of the resolution bandwidth to the frequency range with activated quasi-
peak detector can be canceled using the "CISPR RBW uncoupled" softkey.
Tips regarding measurement time:
●
The relatively long time constants of the quasipeak detector result in long measure-
ment times to yield valid results.
●
Unknown signals should be measured with a measurement time of at least 1 s.
This ensures correct weighting of pulses down to a pulse frequency of 5 Hz.
●
Known signals can be measured with a much shorter measurement time.
After internal switching, the R&S ESWwaits until the measurement result has stabilized
before it starts the actual measurement. Since the level does not change during a fre-
quency scan, known signals (e.g. broadband RFI) can be correctly measured with a
much shorter measurement time.
The CISPR Average Detector
The CISPR Average detector displays a weighted average signal level according to
CISPR 16-1-1. The average value according to CISPR 16-1-1 is the maximum value of
the linear average that has been detected during the measurement.
The detector is used, for example, to measure pulsed sinusoidal signals with a low
pulse frequency. It is calibrated with the rms value of an unmodulated sinusoidal signal.
Averaging is with lowpass filters of the 2nd order (simulation of a mechanical instru-
ment).
The lowpass time constants and the IF bandwidths are fixed depending on the fre-
quency. The main parameters are listed in the following table:
Trace Configuration
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