Miniaturized Hmsiw Bandpass Filter Based on the Coupling of Dual-Iris With Nested Stepped-Impedance CSRRS

Abstract

A novel miniaturized bandpass half-mode substrate integrated waveguide (HMSIW) filter which uses dual-iris coupling method to load complementary split-ring resonators (CSRRs) into HMSIW is proposed in this paper. By modifying traditional CSRRs through nesting method combined with step impedance structure, a nested stepped-impedance complementary split-ring resonator (NSICSRR) structure with higher equivalent capacitance and inductance of CSRR is obtained. Based on the traditional single-iris coupling method, a dual-iris coupling method is developed. And NSICSRR is loaded into HMSIW by using the dual-iris coupling method, which can reduce the resonant frequency of the structure. In order to verify the effectiveness of the technology above in realizing the miniaturization of HMSIW filter, a second-order HMSIW filter is designed and measured. It can be found in the measured results that the filter has the center frequency of 6.35 GHz, the 3 dB bandwidth of 690 MHz, the return loss of better than 14 dB within the passband, and the size of 0.0396λ 2 g. The experimental results are basically consistent with the simulation ones.

Miniaturization Trends in Substrate Integrated Waveguide (SIW) Filters: A Review

“…The authors of [67] designed a novel and miniaturized HMSIW filter. Dual-iris coupling topology is used to couple the resonators together to form a bandpass filter.…”

Design of substrate integrated-waveguide wide stopband bandpass filter for 5G applications

“…Complementary split ring resonator (CSRR) has the characteristic of band-stop [22]. By coupling with CSRRs, just single SIW cavity can exhibit the characteristics of high selectivity [23] [24]. In this brief, a wide stopband bandpass filter (WSBPF) is designed for 5G applications.…”