Decoupling of Antipodal Vivaldi Antenna Array with Polarization Conversion Metasurface

By means of polarization isolation and transmission cancellation, a transmission-type polarization conversion metasurface is employed to suppress the low-band couplings of H-plane wideband antipodal Vivaldi antenna arrays. The meta-atom is composed of one-layer split ring resonator (SRR) and two-layer mutually perpendicular gratings, and has a transmittance of up to 90% in the working bandwidth of 97.8%, which can effectively convert one polarized wave into its cross-polarized wave. Through employed to the decoupling of two-element H-plane antipodal Vivaldi antenna array, the in-band isolation of the array is increased to more than 20 dB. Compared with the original antenna array, the 20 dB isolation bandwidth is increased by 20.8%, and the radiation performance is significantly improved.