A compact dual-band bandpass SIW filter

A novel method for the design of substrate integrated waveguide (SIW) dual-band bandpass filter is presented in this paper. Dual-band response is achieved by TE101 mode and diagonal TE201 (TE102) mode. The resonant frequency of TE101 mode can be adjusted by the location of perturbation vias while the resonant frequency of diagonal TE201 (TE102) mode keeps unchanged. A design example with second-order filter response is given and verified by experiments. The vertically stacked SIW resonators are used here to save the size.