Air-Filled Substrate Integrated Waveguide (AFSIW) Cavity-Backed Slot Antenna for 5G Applications

A cavity-backed slot antenna based on air-filled substrate integrated waveguide (AFSIW) with the technology of multilayer printed circuit board (PCB) is proposed for the 5th generation (5G) mobile communication system at 28 GHz for the first time. The whole antenna is made of five layers and its size is 10 mm ×9 mm. The top and bottom layers are Rogers RT6002 and the medium layer is based on an air-filled substrate integrated waveguide. According to simulation results, compared with the antenna which has the same structure but based on a substrate integrated waveguide (DFSIW), the antenna proposed in this paper increases the gain by 5.8 dB (4.8 dB), the total efficiency by 92.0% (69.7%) and the bandwidth by 990 MHz (207 MHz).