Compact microstrip lowpass filter with sharp roll‐off and ultra‐wide stop‐band

Abstract

A compact microstrip lowpass filter (LPF) with sharp roll-off and ultra-wide stop-band bandwidth is presented. The structure consists of high-impedance meandered transmission lines loaded by triangular and polygonal resonant patches. The cutoff frequency of the proposed LPF is 2.44 GHz and the measured results show good performance such as sharp roll-off, good insertion loss and an ultra-wide stop-band from 2.53 to 35 GHz with the insertion-loss higher than 20 dB. There is a good agreement between the electromagnetic-simulation and measurement results.