You can export the frequency-dependent network data that results from a linear network analysis to a TouchstoneÔ file for use by other analyses. Results can be exported from a design created with either the Schematic Editor or the Netlist Editor.
- Define and run the Linear Network Analysis.
- In a schematic design, expand the icon for the design. Expand the Analysis entry, right-click the LNA solution setup and select Export Solution.
In a netlist design, right-click the icon for the netlist design and select Export Solution to open the Solutions window.
- From a schematic, ensure the chosen setup name and simulation name are shown in the listings in the Simulation fields. (With a netlist design, these fields are read-only.)
- Select the type of data to be saved (S, Y, Z, Zo, or Gamma). The choices depend on the results that are available.
- Select the frequencies for which data can be saved:
- To save the data for all frequencies, check Display All Freqs.
- To save the data for selected frequencies, leave Display All Freqs unchecked and make a selection on the frequencies drop-down menu.
- Optionally, select Check Passivity. EM Design reports any passivity violations in the matrix data. Optionally, set the Passivity Tolerance (default 0.0001 or .01%). (See the S-Parameter Technical Notes for details.
- Select the results and frequencies to
be exported, then click Export. The Export Network Data
Solution window opens:
Select a directory for the export in the Save in: field. Select a file name for the exported data in the File name: field. Select a file type on the Save as type: list, , then click Save.
Options for file format are:
- Data Table (spreadsheet) (.txt file extension)
- Touchstone (.sNp file extension)
- Neutral Model Format (NMF) (.nmf file extension)
- MATLAB (.m file extension)
- CITIfile (.cit file extension)
- The Specify Export Reference Impedance window opens to specify the reference impedance for the Touchstone data:
- Select Override Solution Renormalization (the default) and set the impedance as chosen (50 Ohms is the default). The Touchstone file data are renormalized to the port impedance you specify, if the impedance is not the same as that used for the original analysis. Selecting Do Not Override Solution Renormalization inactivates the Impedance field.
- Choose to Export Noise Data with Touchstone files in Electronics Desktop.
- Choose to include Gamma and impedance comments in the Touchstone file (the default), or to omit them. Omitting the comments can make the Touchstone file much smaller.
- When the impedance information is complete, click OK.
- Click Close on the Solutions window, or leave the window open to make multiple exports, as described next.
Making Multiple Exports
If you want to export several solutions representing variations on the design, leave the Solutions window open. Make the chosen changes to the circuit. The box at the upper-right of the Solutions window displays a red X to show the solution is invalid:
Now, rerun the analysis. The red X disappears to show that a valid solution is available for export. Save the new result as described earlier.