Design and implementation of an ultra-wide stopband microstrip Low-Pass Filter

Abstract

In this project, a microstrip low pass filter (LPF) with wide rejection band, low insertion loss and compact size is investigated. The designed LPF is composed of three open stubs, three identical new shapes (named hourglass) and two rectangular shapes etched in the ground plane. The proposed LPF has acceptable performances in terms of insertion loss, less than 1.5 dB, return loss in the pass-band, less than 9.5 dB, wide stop-band at -20 dB suppression level ranging from 3.88 GHz to more than 20 GHz and size of 35x14 mm 2 .