Design of a novel type of narrow band BPFs using high-Q M-PhC resonators

This paper presents a design of a novel class of high-performance bandpass filters using various types of metallic-photonic-crystal point-defect resonators (M-PhC PDRs). After a brief discussion on the bandgap of PhC structure and resonant modes of M-PhC PDRs, two new filters are designed using proposed M-PhC PDRs. Firstly, a novel trisection filter composed of M-PhC PDRs with hexagonal-lattice is designed at the first time. To realize attenuation pole, a new coupling window is proposed/introduced to realize negative coupling. The coaxial-probe-excitation is applied at ports, while the filter is synthesized in terms of coupling matrix scheme. Then, a novel planar-PhC-filter consisting of M-PhC PDRs and microstrip-line-excitation is synthesized and experimentally realized to validate the possibility of seamless integration of two types of transmission lines. The performances of designed filters are confirmed.