A Substrate Integrated Waveguide Bandpass Filter Based on the Modified CSRRs and the Z shaped slot.

In this paper, a substrate-integrated waveguide (SIW) bandpass filter using the modified complementary spilt-ring resonators (MCSRRs) and the Z-shaped slot is presented. Based on the combination of MCSRRs and the Z-shaped slot, four layouts with MCSRRs in different directions are designed and their distributions of electromagnetic fields are analyzed in some detail. Simultaneously, the causes of the passband generation and change are explained. By comparing the performance of the four layouts, a bandpass filter with the advantages of compact structure, easy integration, and low insertion loss is designed on the basis of face-to-face layout. An additional transmission zero is obtained by introducing the Z-shaped slot. The selectivity is improved duo to two transmission zeros. The proposed filter allows the electromagnetic wave to be propagated in the passband below the cutoff frequency of the waveguide characteristic. To validate the design, the filter is fabricated and tested, and the tested results are consistent with the simulated results. [ABSTRACT FROM AUTHOR]