Novel X-band dual-mode bandpass filter based on the substrate integrated waveguide

摘要: This paper presents a novel dual-mode filter with symmetric transmission zeros based on the substrate integrated waveguide(SIW).This contains two SIW rectangular cavities.By making use of inductive discontinuities in an cavity,two coupling degenerate modes can be excited.Due to phase difference between each side passband are created,so out-of-band rejection is significantly increased.An center frequency 12 GHz has been fabricated and measured using proposed method.Experimental results agree well simulation results.