Measurements and Result Displays
R&S
®
ESW
137
User Manual 1177.6298.02 ─ 08
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The phase selected in the "Phase" block is ignored for both the scan and the
final measurement.
When scan and final measurement are done, the general phase (here: L1)
becomes the selected phase again.
Remote command:
Scan:
Final measurement:
[SENSe:]FMEasurement:LISN:PHASe
High-Pass Filter 150 kHz
Turns the high-pass filter on the LISN on and off.
The filter protects the receiver input from high signal levels below 150 kHz.
Available for measurements with R&S ENV216.
Remote command:
INPut<ip>:LISN:FILTer:HPASs[:STATe]
9.4
CISPR APD Measurements
Access
: [MODE] > "CISPR APD"
The Amplitude Probability Distribution (APD) is a statistical measurement that shows
the "cumulative distribution of the probability of time that the amplitude of disturbance
exceeds a specified level" (CISPR 16-1-1, Amendment 1:2005). So, basically, the mea-
surement determines the likelihood that a disturbance is above a specified level at a
particular frequency (the measurement is usually performed on a fixed frequency).
The amplitude of the disturbance is expressed in terms of the corresponding field
strength or voltage at the receiver input.
The APD is measured at the output of the envelope detector. Therefore, the APD
yields the probability information over the entire disturbance envelope within the mea-
surement bandwidth and a particular period of time.
The APD function has the following advantages.
●
It provides an alternative way to present peak and average measurements (for
example for microwave ovens in accordance with CISPR 11).
●
It is able to calculate true average values.
●
It shows high sensitivity and allows you to measure, for example, a single impulse.
●
It allows you to measure unsteady levels.
CISPR APD Measurements
