Electromagnetic Design of Folded-Waveguide Resonator Filter with Single Finite-Frequency Transmission Zero

摘要

This article presents electromagnetic (EM) design of a new folded-waveguide resonator filter that uses an advanced coupling scheme to achieve the desired asymmetric frequency response with an attenuation pole of finite frequency on the high side of the pass-band. A filter of this type with a fraction bandwidth about 5% at a center frequency of 4.45 GHz has been successfully designed using a commercially available electromagnetic simulator. The designed filter has been fabricated and tested. Simulations and experimental results are presented to validate the design and to show the advantages of this type of filter. This filter also provides a compact size compared with conventional cavity resonator filters.