Compact and low-loss bandpass filter realized in silica-based post-wall waveguide for 60-GHz applications

This paper presents compact and low-loss bandpass filters (BPFs) with ground-signal-ground interfaces that can easily be integrated with RFICs. The filters are realized by post-wall waveguide fabricated into a silica-substrate for the first time. A 59.11-GHz five-pole BPF with a 3.10% fractional bandwidth and a 2.62-dB insertion loss including input- and output- transitions is presented. Its intrinsic area is 8.4 mm by 2.0 mm. The proposed technology can offer practical integrated passive solutions for millimeter-wave applications.