Receiver Mode
R&S
®
ESR
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User Manual 1175.7068.02 ─ 12
If the prescan is performed in parallel with several detectors, typically Peak and Aver-
age, the maxima are determined separately for the two detectors so that the distribu-
tion of narrowband and wideband sources of interference can be taken into account.
For example, the frequency of the maximum determined with the average detector can
be used for the final measurement performed with the CISPR Avg detector and the fre-
quency found in the prescan carried out with the peak detector is taken for the final
measurement using the quasipeak detector.
Consideration of the limit lines ensures that the final measurement is not performed at
frequencies at which the inference level is far below the limit value. A margin below the
limit line can be defined (in dB). Peak values measured in the margin area are also
considered in the final measurement. The margin is valid for all limit lines. Each limit
line is allocated to a trace, i.e. different limit lines are taken for the different detectors.
If no limit lines are activated, the measurement procedure is as if all measured values
would exceed the limit line.
Data Reduction by Editing the Peak List
As an alternative method, it is possible to preset a list of frequencies at which the final
measurements are performed. A typical application is, for example, the statistical
analysis of several units.
The peak list can be either edited manually or can be filled with desired values by
adopting the marker values.
5.1.5
Final Measurement
A final measurement is performed after data reduction, thus reducing the overall mea-
surement time.
The final measurement analyzes only the data that still remains after the preliminary
measurement stages, in other words those frequencies that have been collected in the
peak list. Detectors defined for the final measurement replace those that have been
used during preliminary measurements.
Because the peak list contains a manageable set of frequencies only, the final mea-
surement is also usable in combination with a configuration that requires long mea-
surement times. It is then still possible to perform the measurement in a reasonable
time frame.
During the final measurement, the R&S
ESR performs a measurement on each fre-
quency in the peak list. When done, it updates the preliminary results in the peak list
with those found during the final measurement.
Automatic vs interactive final measurements
The R&S
ESR provides two methods to perform a final measurement: an automatic
and interactive final measurement.
An automatic final measurement measures all frequencies in the peak list automati-
cally. The measurement can be interrupted or aborted, or the measurement mode can
Measurements and Result Displays
