Listing the Input Impedances, VSWR, and S11

To analyze the impedance matching and power efficiency of your antenna across the simulated frequency range, use the following procedure:

1. Select the Source Wire: Right-click on the wire containing the source to open the pop-up menu.
2. Activate the Toolbar: Click the List Currents command to bring up the List Currents toolbar (Fig. 1).
3. Target the Source Segment: Use the slider to select the specific segment where the source is located. If you positioned the source at the exact center, the 50% button will jump there instantly.
4. Access the Input List: Click the Input List button. This opens the Input List dialog box containing:
   • Input Impedance: Real and imaginary parts.
   • Source Data: Input current, voltage, and power.
   • Matching Parameters: Reflection coefficient, VSWR, and $S_{11}$ (Return Loss) in decibels.
5. Visualize the Data:
   • XY Plot: Select a parameter (like VSWR or $S_{11}$) from the list in the upper right corner and press Plot to see its frequency response.
   • Smith Chart: Press the Smith button to visualize how the input impedance moves across the complex plane relative to the characteristic impedance.

Tips

To ensure your reflection data (VSWR, $S_{11}$, and Return Loss) is accurate for your specific system, you can customize the reference parameters and use shortcuts for single-source models.

Setting the Reference Impedance

By default, calculations are often referenced to $50\ \Omega$, but you can adjust this to match your specific feedline or connector:

1. Navigate to the Setup tab in the main workspace.
2. Locate the Settings panel.
3. Enter your desired value in the VSWR Ref. Impedance field.

Quick Access for Single-Source Models

If your antenna has only one source, you can bypass the segment selection slider and access the input data directly:

• Main Menu: Go to Results > List Input Impedances.
• Toolbar: Click the List Input Impedances icon (Z_IN).