UWB BPF with triple notched bands using novel dual-mode SIR and asymmetrical coupling structure

Abstract

A novel ultra-wideband (UWB) bandpass filter (BPF) with triple notched bands is presented in this paper. The basic UWB BPF is realized by a Y-shaped multi-mode resonator. In order to reject the interfered signals, a novel dual-mode stepped impedance resonator is embedded to introduce dual notched bands at 5.85/8.13 GHz. Due to the asymmetrical coupling structure, another notched band centered at 7.12 GHz is implemented as well. Analysis of the filter has been done with classical even- and odd-mode methods. For verification, two sample filters have been simulated, fabricated, and measured. Good agreement is found between the simulations and measurements. The implementation area of the proposed filter is 14.7 × 10.1 mm².