Miniaturized Substrate Integrated Waveguide Bandpass Filters Based on Novel Complementary Split Ring Resonators

In this letter, a miniaturized substrate integrated waveguide (SIW) bandpass filter is proposed. A novel complementary split ring resonator is etched on the top surface of the SIW, which provides a pass band below the initial cut-off frequency of the waveguide TE10 mode. The band width of the filter can be tuned by changing the coupling of the novel structure. A pair of transmission zeros outside the pass band can be produced. The results of simulation and measurement are in good agreement.