Broadband Cross Polarization Conversion for Linear Transmission via Bi-layered Chiral Metasurface

In this paper, bi-layered chiral metasurface is used to achieve the broadband cross polarization conversion (CPC) for linearly polarization transmission. It allows directional control behavior for electromagnetic waves (EM). To enhance the chirality, the unit cell geometry based on split ring resonators (SRRs) is proposed in bi-layer structure. Broadband CPC for linear polarization is achieved through strong chirality. The CPC operates from 13.50 GHz to 16.23 GHz (fractional bandwidth 18.31%) with transmission efficiency greater than 90%. Moreover, the polarization conversion ratio (PCR) for linear transmitted waves are obtained higher than 0.95 and its response maintained stable for incident angle up to 30°. Due to broadband response, high efficiency, and angular stability, the proposed design finds its application in satellite communication systems.