Millimeter-Wave Double Ridge Gap Waveguide Six-Port Network Based on Multi-Via Mushroom

In this article, a six-port network using double ridge gap waveguide based on the multi-via mushroom (M-DRGW) is proposed at millimeter-wave frequency band, which covers the 5G N260 frequency range. First, the stopband of the multi-via mushroom unit cell has been analyzed. Then, simplified schematic of the six-port network is given, and the power divider/coupler based on the M-DRGW is designed to form the six-port junction. For measurement, the peripheral test circuit of the M-DRGW six-port junction is added, and the transitions between the ridge gap waveguide (RGW) and hollow waveguide are added. For the comparison with the performances of the proposed M-DRGW six-port network, the one based on the traditional metallic double RGW (DRGW) has also been designed, fabricated, and measured. The simulated and measured results show that the phase differences between port 1/2 and four output ports are within ±2.5° and ±5°, respectively, and the average value of transmission coefficient is around −8 dB.