CSRR Loaded HMSIW Filtering Power Divider with Embedded Snake-shaped Slots

A filtering power divider is developed by using snake-shaped slots complementary split-ring resonators (SSCSRRs) with substrate integrated waveguide (SIW) and half-mode SIW (HMSIW) in this paper. As the proposed SSCSRR, which mainly consists of conventional CSRR and inside-embedded snake-shaped slots, is loaded into SIW and HMSIW, it can generate stronger evanescent-mode transmission effect than that in the conventional CSRR counterparts and eventually achieves more size reduction. In addition, by adding a connection slot between the face-to-face SSCSRRs, a dual-mode resonator can be constituted based on the cross-coupling scheme, which can generate an extra transmission zero near the passband and ultimately improve the selectivity. Based on the proposed SSCSRR and its cross-coupled version, a SIW/HMSIW filtering power divider is designed, which exhibits a center frequency of 2.58 GHz, a fractional bandwidth of 7.7%, an isolation over 15 dB and a return loss over 20 dB.