A Wideband Crossover Based on E-Plane Groove Gap Waveguide for Antenna Feed Networks

This communication proposes the design and fabrication of a novel wideband millimeter-wave crossover using gap waveguide (GW) technology, aimed at low-loss and high-power applications in Ka-band. To address fabrication challenges at millimeter-wave frequencies, GW technology is employed. An E-plane GW-based crossover is designed to offer broadband performance, high return loss, acceptable coupling flatness, and high isolation. To validate the performance of the proposed designs, a prototype of a crossover with input WR-28 rectangular waveguides is manufactured and tested. Measurement results indicate that the fabricated crossover achieves return and insertion losses better than 17.3 dB and 0.58 dB, respectively, and an isolation level exceeding 26.7 dB within the 26.5 to 40 GHz frequency range. Additionally, the proposed millimeter-wave structures exhibit a breakdown power level in the kilowatt range, meeting high-power requirements of antenna feed networks.