Design of wideband millimeter-wave bandpass filter using substrate integrated waveguide

This paper presents the design of wideband millimeter-wave bandpass filter based on Substrate Integrated Waveguide technology. The filter is constructed by etching rectangular slots on the top metallic plane of SIW cavity. An effective lossy circuit model at mm-Wave frequencies is proposed with accurate parameters which have been extracted from full-wave electromagnetic simulations for the proposed wideband filters. As sample, two SIW filters are designed: A wideband fifth-order SIW BPF which has insertion loss of less than 1.5 dB and 28% bandwidth at a center frequency of 45GHz. The other a fourth-order BPF with less than 2Db as insertion loss and 20% bandwidth at a center frequency of 55GHz.