A novel filtering crossover based on ridged substrate integrated circular cavity with flexibly allocated channel frequencies

A novel filtering crossover based on ridged substrate integrated waveguide (RSIW) circular cavity with flexibly allocated channel frequencies is proposed in this paper. The crossover functionality is realized through exploitation of orthogonally TM110 (mode A) and TM110 (mode B) modes within the central RSIW circular cavity. Due to the loading of the ridges in the central RSIW cavity, the resonant frequencies of the TM110 (mode A) and TM110 (mode B) modes are split and the central frequencies of the two channels can be allocated flexibly. A filtering crossover prototype operating at 3 GHz/4 GHz is designed, fabricated and measured. The measured results are in good agreement with the simulated results.