Lowloss planar bandpass filters for millimeter-wave application

A new printed planar technology is introduced for efficient TEM bandpass filters in millimeter band. The new technology is self-packaged and shows excellent insertion losses compared to microstrip filters. The designs are based on newly introduced ridge gap waveguide, which is composed of printed parallel plate waveguide surrounded by arrays of bed of mushrooms. Several example are designed and optimized. Sample measured results are presented.