HMSIW bandstop filter loaded with half complementary split-ring resonator

A novel half-mode substrate-integrated waveguide (HMSIW) bandstop filter loaded with a half complementary split-ring resonator (HCSRR) is investigated. The experiment indicates that the novel HCSRR shows almost the same resonant characteristic but half size in contrast with the original CSRR. Then the proposed HCSRR is etched on the middle of the HMSIW and a compact bandstop filter is realised. A practical example for a HMSIW bandstop filter is fabricated and measured. The measured results show good agreement with the simulated ones.