Folded-Waveguide Resonator Filter With Asymmetric Frequency Response

A new 4-pole bandpass tiller design based on a folded-waveguide (FWG) resonator structure is presented. The filter uses an advanced coupling scheme to achieve a desired asymmetric frequency response with an attenuation pole of finite frequency on the high side of the passband. A full-wave simulator has been employed for designing the filter. The proposed filter circuit design has been implemented. It has been found that the experimental results of constructed filter are in close agreement with simulation results. This filter also provides an improved selectivity characteristic with compact size compared with the conventional resonator filters