Network Analyzers using S4VNA software

The Analyzer allows to save S-parameters to a Touchstone file. Files in this format are typical for most circuit simulator programs. The Touchstone file contains frequency values and S-parameters.

The Touchstone file saving function is applied to individual channels. Activate the channel to use this function (See Selection of Active Trace/Channel).

The *.S1P files are used for saving S11 and S22 parameters of a one-port device.

The *.S2P files are used for saving all four S-parameters of a two-port device.

The *.S3P files are used for saving all the nine S-parameters of a three-port device.

The *.S4P files are used for saving all the sixteen S-parameters of a four-port device.

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The Touchstone file contains comments, header, and trace data lines. The header starts from the «#» symbol. Comments start from the «!» symbol. Comment contains following strings:

•Model, serial number, software version.

•Save date (in dd.mm.yyyy hh:mm:ss format).

•The name of the saved parameters and their units.

The *.S1P Touchstone file for one-port measurements:

The *.S2P Touchstone file for two-port measurements:

The  *.S3P Touchstone file format for three-port measurements:

The *.S4P Touchstone file format for four-port measurements:

Hz — frequency measurement units (kHz, MHz, GHz);

FMT — data format:

•RI — real and imaginary parts;

•MA — linear magnitude and phase in degrees;

•DB — logarithmic magnitude in dB and phase in degrees;

Z0 — reference impedance value;

F[n] — frequency at measurement point n;

{…}’ — {real part (RI) | linear magnitude (MA) | logarithmic magnitude (DB)};

{…}” — {imaginary part (RI) | phase in degrees (MA) | phase in degrees (DB)}.

Touchstone File Saving

 

 

 

 

 

Touchstone File Recalling

The Analyzer allows to recall data from the Touchstone files. Data can be loaded to memory traces or to data traces. When loading data to data traces, the Analyzer switches to  hold mode to avoid writing  over the recalled data with current data. When loading data to the memory traces, the sweep hold does not occur.

If the frequency scale of the Touchstone file does not correspond with the current Analyzer frequency settings, the user is prompted to choose between interpolating the data on recall or changing the Analyzer settings. The following message appears: