Creating the Model

Create the model in CADFEKO. Define any ports and sources required for the model. Specify the operating frequency or frequency range for the model.

  1. Request a standard configuration and delete the existing S-Parameter configuration.
  2. Delete the FEM line ports.
  3. Expand shielded_filter and delete Feed1 and Feed2.
  4. Set the region properties of both regions back to the the default, namely MoM/MLFMM with surface equivalence principle (SEP) - default.
  5. Set the air region back to Free Space.
  6. Create two vertical plates between the microstrip feeding edges and the ground plane.
    1. Set the Selection type to Edges and select the leading edges of the microstrip line (at the input and output locations of the model).
    2. Create a copy of these edges.
    3. Select the copied edges (parts in the tree) and use the Sweep tool to sweep the edges in the negative Z direction a distance of substrate_height.
  7. Create edges for the edge ports on the vertical plates.
    1. Split the vertical plates on a perpendicular plane at a height exactly halfway between the microstrip line and ground plane.
  8. Union all the parts in the tree.
  9. Create edge ports on the edges separating the two halves of the vertical plates.
    Note: Edge ports must be surrounded on all sides by the same medium - these cannot be on the surface of a finite dielectric.
  10. Set all the face properties to PEC except for the boundary surface between the dielectric layers.
  11. Set a local mesh size on the microstrip faces of strip_width/2.