Design of dual-band bandpass SIW filter with DGS

The proposed filter is implemented using substrate integrated waveguide (SIW) technology featuring compact size, low cost, and high power-capacity. The stopband improvement is achieved by using defected ground structure (DGS) which is etched on the ground plane of the SIW cavity. Based on the concept of DGS, a new class of SIW double bandpass filters are designed, fabricated, and measured around 4.87 GHz and 5.61 GHz, respectively. The proposed filter, fabricated using standard printed circuit board technology, has the advantages of compact size, good S-parameters characteristics and low cost. Simulated and measured results are presented and discussed to show promising performances of the proposed filters.