Spurious Free Non Uniform Width Dielectric Loaded Filters

This paper presents the design of dielectric loaded waveguide filters with wide spurious free bandwidth. Resonators loaded with non-uniform width ceramic blocks are used to spread out the higher order spurious resonances along with the silver plated hole/ridged ceramic blocks in I/O resonators to reduce the overall size of the filter. The proposed designs demonstrate 2.44 times fo spurious free bandwidth. Simulated results for a six pole Chebyshev non-uniform width ceramic blocks mixed with a hole plated ceramic loaded filter and a non-uniform width ceramic blocks mixed with a silver plated ridged ceramic loaded filter are presented in the paper exhibiting excellent spurious performance.