R&S ZVH
Cable and Antenna Test Mode
Performing Cable and Antenna Measurements
Operating Manual 1309.6946.12 - 09
41
2.1.3 1-Port Cable Loss Measurements
The cable loss measurement is a
reflection measurement on an open
cable. It evaluates the amount of
energy that a signal loses while
traveling through a cable. .The amount
of lost energy depends on the
frequency and the length of the cable
► Press the MEAS key.
► Press the "1-Port Cable Loss"
softkey.
The R&S ZVH shows the result (graphically) over the specified frequency range
(span) in dB. The numerical result is the average cable loss over the specified
span. The image above shows a typical cable loss result, with a steadily declining
loss over the selected frequency range and several maximums and minimums.
By default, the R&S ZVH evaluates the cable loss over its entire frequency range (full
span of the R&S ZVH). When you reduce the span, make sure to define a span that is
appropriate for the measurement, especially for high center frequencies, and consider
the cable length and the wavelength of the selected center frequency. For a typical
cable loss trace, you should select a span that is large enough to evaluate at least one
peak and one minimum. Otherwise, the result might not be valid.
If the cable loss is constant over a large span (for example in case of low center
frequencies), you can select any span.
Note that if the cable loss is greater than 20 dB, you are better off using the S21
measurement, because the cable loss measurement might yield invalid results.
