Compact Ultra-Wideband Bandpass Filter Based on SIW and DGS Technology with a Notch Band

Abstract

A novel compact ultra-wideband (UWB) bandpass filter (BPF) with a notch band is proposed and implemented. The filter is realized by using a half-mode substrate integrated waveguide (HMSIW) and two tapered defected ground structures (DGS). An L-resonator bandstop filter is integrated with the UWB filter to reject the undesired wireless local-area network (WLAN) radio signals. The UWB filter has a very compact size of 13 mm by 11 mm. The measured BPF insert loss is less than 1.2 dB throughout the pass band from 3.0 GHz to 11.1 GHz, the variation of group delay less than 0.15 ns except for the notch band, and a stop band with 20 dB attenuation up to at least 14 GHz.