R&S ZVB - Page 204

R&S
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ZVA / R&S
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ZVB / R&S
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ZVT GUI Reference
Trace Menu
Operating Manual 1145.1084.12 – 30 189
Touchstone files use the point as Dec. Separator and contain the reference impedance of the associated
ports in the file header; see Trace File Formats. The following export options are available for Touchstone
file export:
 Output Format selects the format for the exported trace data. In the Real - Imag format, each
complex measurement value is represented by its real and imaginary part. It is also possible to
store the linear magnitude and phase (lin Mag-Phase) or dB magnitude and phase (dB Mag-
Phase) of each value.
 Select Ports opens a dialog to define the port assignment for the created Touchstone (*.s<n>p)
file.
 Ask before Overwriting activates a message box to be displayed before an older trace file with the
same file name and directory is overwritten.
 Export All Channels causes the analyzer to export the trace data for all channels in the current
setup to separate Touchstone files. The selected Touchstone file name is automatically extended
by the channel identifier, e.g.: <File name>Ch1.s2p, <File Name>Ch2.s2p...
 Replace Missing Values by 0 allows the export of incomplete, uncalibrated sets of n-port S-
parameters to an *.s<n>p file (n > 1): at least one of the related S-parameters has to be
measured, the missing S-parameter columns are filled by zeros.
 Renormalize S-Parameter allows for a renormalization of the S-matrix prior to Touchstone file
export.
[See Reference Impedances for background information on renormalization in general, but note
that the reference impedance for the Export S-Matrix function can be selected independently from
the setting in the Port Configuration dialog.]
At the Export S-Matrix function (data access point 1 in the data flow diagram), S-parameters are
normalized to the connector impedances of the related physical ports, as defined in the Connector
column of the Port Configuration dialog and the settings in the Available Connector Types dialog.
If Renormalize S-Parameter is disabled, they are exported according to these original
impedances.
If Renormalize S-Parameter is enabled, the reference impedance of the S-parameters is changed
to the specified target Impedance.
For waveguide "connectors" the impedances are frequency-dependent; the analyzer uses the
"wave impedance of the basic transverse electric mode" as reference impedance:
Zref = Z0 / sqrt [1 – (fc/f)2],
where Z0 denotes the wave impedance of free space, and fc the cut-off frequency of the mode.
 Impedance indicates the reference port impedance that is written into the generated Touchstone
file (irrespective of the renormalization setting) and used as a target impedance for
renormalization (if selected). The default reference impedance is 50 Ω.
Remote control:
MMEMory:STORe:TRACe:PORTs
MMEMory:STORe:TRACe:PORTs:INComplete
MMEMory:SETTings:RENorm:MODE
MMEMory:SETTings:RENorm:RIMPedance
MMEMory:SETTings:RENorm:STATe
Select Ports
Defines the port assignment for the created Touchstone (*.s<n>p) file.