How to feed a waveguide dielectric resonator filter

This article is a practical guide on how to feed a waveguide dielectric resonator filter.

As an example, we will look at a waveguide filter with dielectric resonators solved using the finite element method (FEM). The outer waveguide faces are set to perfect electric conductor (PEC).

The dielectric resonator filter model.



The dielectric resonator filter model with mesh with an active cutplane showing the FEM dielectric regions.


Since this shielded waveguide filter is a non-radiating microwave component containing dielectric regions, the example is well suited to be solved using FEM. For this example [1], the waveguide structure will be excited using a waveguide port.

A good approximation of the physical model is to place the waveguide port in the plane where the waveguide transitions into the coaxial adaptor. The waveguide port must cover the full cross-section of the face. Boundary edges forming the port shape must be set to PEC.

To excite the filter:

A face is selected on one side of the filter.


A waveguide port is added to the filter.



See Ports and sources in Feko for more information on ports, sources as well as practical examples on how to feed typical structures in Feko.



[1]: Hiroshi Shigesawa et al., “Two-path cutoff waveguide dielectric resonator for filters”, IEEE Trans. Microwave Theory and Techniques, vol. 7, pp.1105-1112, July 1989.