Low loss planar dielectric waveguide filter with cross coupling using LTCC technology at 60GHz band

This paper proposes a filter with on transmission zero based on a combination of a vertically stacked and a horizontally arranged planar dielectric waveguide with cross coupling and low insertion loss were developed for 60 GHz band applications. The fabricated BPF exhibited one transmission zero at the higher frequency side of the pass band due to the post gap coupled waveguide. At the center operation frequency of 57.7 GHz, the 20 dB bandwidth of the BPF is 1.0 GHz, which is almost 2% of the center operation frequency, and the insertion loss is 1.12 dB. One transmission zero reach approximately 25 dB at 59.0 GHz. Unlike shifted frequency, demanded specifications were satisfied with the measured result.