Rohde & Schwarz Cable Rider ZPH, User Manual

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Cable and Antenna Test Mode
R&S
®
Cable Rider ZPH
102 User Manual 1321.0950.02 ─ 03
12 = Cable frequency information
13 =
Config Overview
14 = CAT softkey menu
● Performing Cable and Antenna Measurements ....................................................102
● Configuring Cable and Antenna Tests .................................................................. 114
● Analyzing Measurement Results ...........................................................................124
7.1 Performing Cable and Antenna Measurements
In order to get an idea about the problems in a transmission system that is as accurate
as possible, the R&S Cable Rider ZPH features several measurements. Each mea-
surement shows a different aspect of the cable characteristics.
● Reflection Measurements ..................................................................................... 102
● Distance to Fault Measurements .......................................................................... 103
● 1-Port Cable Loss Measurement .......................................................................... 105
● Smith Chart ........................................................................................................... 106
● Phase Measurement .............................................................................................108
● Calibrating Measurements .................................................................................... 109
7.1.1 Reflection Measurements
The reflection (S11) measurement is a good way to get an idea if the transmission sys-
tem works properly. If unusual amounts of signal power are being reflected, you can
guess that there is something wrong in the system.
A reference signal is transmitted along the transmission system, and this signal is
reflected back by a discontinuity along the transmission line, usually by an impedance
mismatch. This reflected signal is measured and compared with the reference signal to
determine the loss of power.
The reflection measurement can be performed in the following measurement formats:
●
Magnitude (return loss in dB)
Return loss is power loss in dB, measured over the specified frequency range of
the transmission system. The return loss is the default measurement mode in R&S
Cable Rider ZPH.
●
SWR
The standing wave ratio, SWR provides the ratio of the maximum and minimum AC
voltages along the transmission line caused by the reflections.
1. Press the MEAS key
2. Select the "SWR" or "Return Loss" softkey.
The R&S Cable Rider ZPH starts the reflection measurement over its entire fre-
quency range with the selected measurement format.
Figure 7-3 shows an example of a reflection measurement in magnitude and SWR for-
mat without any major faults in the cable or the antenna.
Performing Cable and Antenna Measurements