Synthesis of Transversal Bandpass Filters on Stacked Rectangular $ H$ -Plane Waveguide Cavities

Abstract

In this paper, a new transversal configuration is presented for waveguide bandpass filters (BPFs) on stacked rectangular $ H$ -plane waveguide cavities. Different from the conventional ladder BPFs, cavities constituting the proposed transversal BPFs are arrayed in a stacked manner. Odd- and even-mode resonators of transversal BPF are realized by TE101 and TE102 modes of rectangular $ H$ -plane waveguides, respectively. Using the configuration proposed herein, the realization of an $N$ th-order filter could be decomposed into realizations of $N$ first-order subfilters, and each subfilter could be realized independently, which is guaranteed by the unique array of resonators of transversal filters. Therefore, the complexity of realizing BPFs could be reduced, especially for filters with multiple transmission zeros (TZs). A class of transversal filters, including BPFs and dual-band filter, are synthesized, fabricated, and measured to verify the approach.