A Gap Waveguide Fed Circular Polarization Antenna in the Millimeter-Wave Range

In this paper a simple diamond-shaped slot antenna working in the millimeter-wave 5G band of 60 GHz, with circular polarization (CP), high radiation efficiency and broadband performance both in matching and axial ratio (AR) is presented. The antenna is implemented in Gap Waveguide (GW) technology, namely Ridge Gap Waveguide topology. The feeding system is a standard waveguide (WR-15) to RGW transition. The simulation results demonstrate a 14.52% reflection coefficient and AR bandwidth (|S 11 ˂ -10 dB| and AR ˂ 3dB) covering 59-68 GHz (> 9 GHz) The maximum gain of the system is around 7 dB, with an efficiency close to 98%.