HFSS15: Renormalizing S-Matrices

You can renormalize an S-matrix to a specific port impedance when you set up a wave port. (It is the final step in the Wave Port wizard.) Or you can return to the Wave Port dialog box by double-clicking the wave port icon in the project tree, and then clicking the Post Processing tab. For driven modal problems, you can also edit the renormalization settings and impedance value in the wave port Properties dialog.

To renormalize an S-matrix to a specific port impedance:

1. If you have already set up the wave port on the desired object face, double-click the wave port’s icon in the project tree.

The Wave Port dialog box appears.

2. Click the Post Processing tab.

The Port Renormalization choices include:

• Do Not Renormalize (the default)

• Renormalize All Modes. This enables the Full Port Impedance text box. The default impedance for re-normalization of each port is 50 ohms.

For a driven modal solution, if you want to enter a complex impedance, enter it in the following form:

<re> + <im>j

(For a driven terminal solution using a waveport, only the real part of the impedance is required.)

• If there are multiple modes, you can select Renormalize Specific Modes. This enables the Edit Mode Impedances button. This opens a editable table with the impedances for each mode.

3. Click OK to apply the selected values and close the dialog.

For wave ports in driven modal problems, if you choose to edit the renormalize values through the Properties dialog:

1. Select the wave port to edit.

The docked Properties dialog shows the properties for the wave port.

2. Check the Renormalize All Modes box.

This enables the Renorm Imped field.

3. Set the Impedance value.