R&S QAR50, Руководство пользователя

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Measurements and result displays
R&S
®
QAR50
40 User Manual 1179.4992.02 ─ 02
Figure 8-2: Principle of the transmission measurement
1 = Cluster 1
2 = DUT
3 = Cluster 2
straight line = Stimulus signal
dotted line = Attenuated signal
dashed line = Reflected energy
For more information about the result display available for the transmission measure-
ment, see
Chapter 8.3, "Result displays" , on page 41.
8.2.3 Phase measurement
In addition to reflection and transmission characteristics, the phase characteristics of
the DUT are also of interest. When a stimulus signal hits the DUT, the DUT changes
the phase characteristics of a signal by a certain amount, depending on its thickness
and material.
For the phase characteristics, both clusters send a signal that passes through the DUT.
The opposite cluster measures the phase of the received signal. The resulting phase
results are the average of those two measurements.
To calculate the phase difference, the R&S QAR50 compares the phase of the normali-
zation measurement (empty space) to that of the actual measurement.
Measurement