Dual Circularly Polarized Aperture Array Antenna in Gap Waveguide for High-Efficiency Ka-Band Satellite Communications

Abstract

A novel fully metallic Ka-band dual circularly polarized antenna array is presented in this contribution. It consists of 64 circular apertures (8×8) and it is implemented in gap waveguide technology. The antenna includes 4 layers, which are completely metallic, leading to a highly efficient performance. The experimental results confirm reflection coefficient values lower than-10 dB from 29 GHz to 31 GHz as well as stable radiation patterns throughout the whole frequency range. Good average axial ratio (AR) of 1.5 dB has been measured in the working band for both polarizations. Measured directivity is 28 dBi and antenna efficiency keeps close to 80%.