A wideband bandpass filter based on stepped impedance stubs and substrate integrated coaxial line

In this paper, a novel wideband bandpass filter is proposed using a stepped impedance stubs resonator and substrate integrated coaxial line (SICL) technology. The resonator produces three resonant frequencies and two attenuation poles near the edges of the passband, so a wide bandwidth and a sharp rejection can be obtained. A filter prototype with compact size is simulated and the results indicate that the proposed filter centered at 13.16 GHz is realized with a bandwidth of 28.3%. The filter features low insertion loss, wide stopband, and low crosstalk.