Wideband dual-mode bandpass filter using a modified right-triangular patch resonator overlapped with input/output DMS

Abstract

A novel and compact dual-mode wideband bandpass filter (BPF) with multiple transmission zeros is designed, fabricated, and measured in this paper. This filter consists of a modified right-triangle patch resonator with two orthogonal narrow-strip stubs and improved input/output defected microstrip structure (DMS). The designed resonator and DMS show dual-mode and dual-bandgap characteristics, respectively. The equivalent circuit models are described and their element values are also extracted by the full-wave EM simulator. The presented BPF is constructed by cascading the stub of patch resonator with the input/output DMS and overlapping partly with each other between the stub of resonator and middle conductor strip of input/output DMS. The EM simulated result has been confirmed by an experimental one and they have shown good agreement with each other. The measured result exhibits wide passband and low insertion loss characteristics for the proposed filter.