A NOVEL COMPACT SUBSTRATE INTEGRATED WAVEGUIDE FILTER USING MINIATURIZED STEPPED IMPEDANCE METAMATERIAL UNIT CELL

Novel substrate integrated waveguide bandpass filters are presented by using a complementary split-ring resonator. The proposed stepped impedance octagonal complementary split-ring resonator (SI-OCSRR) presents high miniaturization compared to the classical octagonal complementary split-ring resonator (O-CSRR). Additionally, two different filter configurations consisting of two cascaded cells with different coupling between the CSRR are proposed. A comparison between the proposed filters and the other ones reported in the literature has proven the advantages of the proposed filters, namely compact size, high in-band return loss, and ease of integration. A good agreement between the simulated and measured results has been reached, which verifies the validity of the design methodology.