A SUBSTRATE INTEGRATED WAVEGUIDE BANDPASS FILTER USING NOVEL DEFECTED GROUND STRUCTURE SHAPE

In this paper, a X-band wideband bandpass filter based on a novel substrate integrated waveguide-to-defected ground structure (SIW-DGS) cell is proposed. In the cell, the DGS is etched on the top plane of the SIW with high accuracy, so that the performance of the filter can be kept as good as possible. Finally, the filter, consisting of three cascaded cells, is designed and measured to meet compact size, low insertion loss, good return loss as well as smooth group delay. There is good agreement between the measurement and simulation results.