Extreme-Angle Transmission Enhancement for TM- Polarized Waves Empowered by Brewster Effect of Metasurface

Abstract

Impedance mismatch generally exists upon interfaces between different media. This is undoubted for TM- polarized waves, when the angles of incidence increase. Despite Brewster effect for transverse-magnetic (TM)-polarization, permittivity of dielectric in nature is usually small and relatively limited. Therefore, it’s difficult to achieve transmission enhancement at extreme incident angles. In this work, we propose a novel metasurface to expand Brewster effect of dielectric and obtain high-efficiency transmission at extreme incident angles. The 90°-counterclockwise-rotated "L"-shaped structure is etched on the surface of F4B substrate, while a combination of both is vertically placed on the middle of Fiber Reinforced Polymers (FRP) plate. Two arms of "L"-shaped structure are equivalent to electric dipoles and synthesized to new Brewster effect (incident angle over 70°), due to intense standing wave effect. Thus, transmission amplitude of electromagnetic (EM) waves is increased by more than 1dB compared with pure FR4 plate in X-band. This work provides an effective method of enhancing extreme-angle transmission of EM waves and may find applications in radar, communications, and others.