R&S ZVL
Measurement Examples
Advanced Tasks
Operating Manual 1303.6580.32-05
110
Advanced Tasks
Time Domain Measurements
With option ZVL-K3,
Time Domain,
you can view the measurement results as a function of time.
To set up a time domain measurement...
Reset the analyzer to ensure that the following operating mode is set: Channel - Sweep - Sweep
Type: Lin. Frequency, Trace - Meas.: S21, Trace - Format: dB Mag.
Open the
Trace - Meas
menu and select the measured quantity to be transformed (preferably: an S-
parameter or ratio).
Click
Trace - Traces - Time Domain Transform - Time Domain
to transform the active trace to the time
domain.
The transformed trace is displayed in the active diagram area. To refine the analysis, you can modify the
number and position of the sweep points
(Channel - Sweep - Number of Points, Channel - Stimulus),
select a different transform type and window for profiling
(Trace - Traces - Time Domain Transform -
Define Transform...)
and vary the time range
(Trace - Traces - Time Domain Transform - Stimulus
Transform).
To eliminate an unwanted response from the measured trace...
Calculate a time domain transform as described above, Setting up a time domain measurement.
Click
Trace - Traces - Time Domain Transform - Define Time Gate
and
place a time gate on the
transformed trace. To remove a single response use a
Notch
gate type. To remove everything outside
a specified area, use a
Bandpass
gate type.
Click
Trace - Traces - Time Domain Transform - Time Gate
to enable the time gate. If necessary, go
back to the
Define Time Gate
dialog to correct your time gate settings.
Click Trace - Trace Func - Transform - Frequency Domain.
The frequency domain trace now corresponds to the modified time domain trace which is transformed
back into the frequency domain
.
Distance-to-Fault Measurements
With option ZVL-K2,
Distance-to-Fault,
the analyzer can locate faults and discontinuities on cables and
transmission lines. The faults produce spikes on the trace; the x-axis shows the distance from the
calibrated reference plane. Most conveniently the reference plane is set to the analyzer test port PORT 2
.
Preparing a Distance-to-Fault Measurement
Consider two RG141A cables of different length. The first cable can be connected to PORT 2 of the
analyzer using a suitable adapter. The second cable is connected to the first cable using a second adapter
and either left open or terminated with a matched load. The first cable contains a fault which is to be
located by the network analyzer. The lengths of the cables and adapters are shown below.
