Computer aided design of asymmetric e-plane bandpass filters with improved stopband performance

Computer Aided Design method has been developed to synthesise E-plane band-pass filters with improved stopband performance. The theoretical investigation of a novel type of E-plane bandpass filters with improved stopband performance composed of a metal insert which when mounted in the rectangular waveguide housing introduce ridges in the resonators is presented. The solution not only maintaining the simplicity of the structure, but also providing good stopband performance and reducing the overall length of the filter. Design data for a five resonator X-band (8.2 - 12.4 GHz) E-plane bandpass filter with ridges at 9.5 GHz midband frequency are given.