Modeling and Analysis of Novel CSRRs-Loaded Dual-Band Bandpass SIW Filters

Dual-band substrate integrated waveguide (SIW) bandpass filter (BPF) operating at 6 GHz and 12 GHz is presented. The two identical complementary split-ring resonators (CSRRs) make up the resonant unit. And the two CSRRs are strongly coupled. For the first time, two resonant units are horizontally etched on the upper metal of SIW. The equivalent circuit model of the novel dual-band SIW BPF is established and analyzed in detail. To realize the miniaturization design of the filter, a dual-band half-mode SIW BPF is proposed. The center frequencies of the passbands are located at 4.56 GHz and 9.36 GHz. The filter exhibits the characteristics of higher slope selectivity, lower insertion loss, wider 3 dB fractional bandwidths and compact size.