Fully Printed Gap Waveguide With Facilitated Design Properties

An improved concept is introduced to facilitate the design of low-loss planar circuits using printed gap waveguide technology. The method is based on using separate layers to realize the EBG cells and the lines. As a result, the operating bandwidth of the waveguide is increased compared to the printed ridge gap waveguide. Also, the design process is simplified regarding the placement of the cells around the resonators and lines. Measured results of a line with two 90° bends and a quadruplet bandpass filter are presented that prove the concept. A transition to microstrip line is used in order to acquire the ability to use test probe fixture.