Design of Broadband Gap Waveguide Transitions for Millimeter-Wave Antenna Arrays

This paper presents two novel transitions in gap-waveguide technology. The first transition, a rectangular waveguide to groove-gap waveguide in the V band, shows a return loss better than 15 dB within a 15% bandwidth. The second transition, a rectangular waveguide to ridge-gap waveguide in the Ka band, exhibits 20% bandwidth with a return loss level above 20 dB. These transitions are aimed to serve as input ports in corporate feeding networks designed in gap-waveguide technology. Such technology has recently demonstrated to be advantageous to properly distribute the energy in high-gain array antennas.