Defining an Infinite Planar Multilayer Substrate

Define an infinite planar multilayer substrate.

Some applications for infinite planar multilayer substrates are as follows:
  • Add a PEC ground plane at the top and bottom layers to model a stripline.
  • Add a PEC ground plane at the bottom layer to model a microstrip.
  • Use the substrate (without a PEC ground plane) to model real earth.
  • Use a finite thickness substrate without any ground plane to model a printed antenna (for example, a log-periodic antenna).
  1. On the Construct tab, in the Structures group, click the  Planes/Arrays icon. From the drop-down list, select  Plane / Ground.
    Figure 1. The Plane / ground dialog.


  2. From the Definition method drop-down list, select Planar multilayer substrate.
  3. Under Infinite layers, specify the top and bottom infinite layers:
    1. In the Top layer medium drop-down list, select the medium for the top layer that extends into infinity.
    2. In the Top layer ground plane drop-down list, specify whether the top layer should have a ground plane.
      • If the top layer has no ground plane, select None.
      • To add a ground plane for the top layer, select PEC.
    3. In the Bottom layer medium drop-down list, select the medium for the bottom layer that extends into infinity.
  4. Click Add to add an additional layer. Click Remove to remove the selected layer from the substrate.
  5. For each layer:
    1. From the Ground plane drop-down list, select one of the following:
      • To remove the PEC ground plane located below the current layer, click None.
      • To add a PEC ground plane located below the current layer, click PEC.
    2. Specify the layer thickness.
    3. Specify the medium.
    Note:
    • The top layer and bottom layer extends into infinity.
    • In the CADFEKO GUI, the first layer is indexed as 0.
    • In the CADFEKO API, the first layer is indexed as 1.
  6. In the Z-value at the top of layer 1 field, specify where the top of layer 1 is located.
  7. Click OK to define the infinite planar multilayer substrate and close the dialog.