Design and implementation of microstrip Ultra-Wide Band Bandpass filter with and without dual notched band

Abstract

This work presents a novel compact ultra-wideband bandpass filter (UWB BPF) with and without dual notched band. It is based on symmetrical structure of a simple uniform line loaded by a stepped-impedance stub (SIS) connected at its center. Two notches are inserted at 5.8 and 8.0 GHz to eliminate WiMAX and satellite communication interferences by embedding two U-shaped slots in the ground plane. The proposed UWB BPF with dual-notch is simulated, fabricated and measured. Satisfactory results are obtained, achieving good performances in terms of ultra-wide impedance bandwidth of 7.7 GHz (2.9 - 10.6 GHz) with a fractional bandwidth of 118.8 %, return loss better than 13 dB, an upper stopband attenuation higher than 20 dB up to 16 GHz, and a sharp selectivity.