R&S ESR Series User Manual page 312

®
R&S ESR
The example is based on the following configuration.
Center frequency
Span
Unit
Reference Level
Attenuation
RBW
VBW
Sweep time
Detector
All other settings are in their default (preset) state.
The first picture shows the resulting noise characteristics in the time domain (zero
span). The x-axis shows the time. The y-axis shows the level of the "signal" in dBm.
P
max
The second picture shows the corresponding CISPR APD function. Here, the x-axis
represents the disturbance levels in dBm. The scale of the axis is arbitrary. By default,
its range is a 100 of the unit you are working with. The end point of the x-axis repre-
sents the reference level.
The y-axis represents the statistical frequency that a particular level value will turn up
with. The y-axis is a logarithmic axis by default. Like the x-axis, its scale is arbitrary.
As you can see, the probability that levels above P
level values, the probability that a particular level occurs increases (until P
reached). Because the noise has no spikes, the APD curve is falling (more or less)
smoothly.
User Manual 1175.7068.02 ─ 12
is the highest level that has been measured, P
Spectrum Measurements
100 MHz
Zero span (0 Hz)
dBm
-30 dBm
20 dB
1 MHz (EMI)
10 MHz
100 ms
Auto Peak
is the lowest level.
min
will occur is zero. With falling
max
Measurements
has been
min
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