Compact Dual-band UWB Filters for Wireless Private Network Communication

In this letter, a dual-band bandpass filter using sixteenth-mode substrate integrated waveguide (SMSIW) cavity and a novel ultra-wideband (UWB) bandpass filter (BPF) using eighth-mode SIW (EMSIW) cavity are presented. The TE101, TE102 and TE201 resonant modes of the SIW a circular resonator are used to design the proposed filters. The complementary splitring resonators (CSRRs) are employed in the middle of the circular SIW cavity to produce one transmission zero (TZ), so the dual-band BPF and UWB BPF with high selectivity are realized. The proposed filters possess compact size, because of the EMSIW and SMSIW cavity. The dual-band filter is fabricated in SMSIW cavity and the center frequencies are 8.49 GHz and 12.8 GHz with 3-dB FBWs 30% and 31.25%, respectively. The UWB filter is simulated in EMSIW cavity and its center frequencies are 9 GHz, 11.65 GHz and 14.9 GHz with FBW of 78%. The minimum insertion losses are expected to be 0.53/0.76 dB and 1.25 dB.