Independently Controllable and Dual-polarized Reconfigurable Intelligent Surface with Wide-angle Insensitivity

In this paper, a dual-polarized reconfigurable intelligent surface (RIS) structure with a wide angle of incidence is proposed. The unit is composed of two layers of the dielectric substrate, radiation patches, ground layer, bias line, PIN diodes and metallic vias. The square metal patch is connected to the metal strip through two PIN diodes in two directions (X or Y direction) to achieve dual polarization and independent control. Additionally, metallic vias are introduced into the RIS unit, which can reduce the interference caused by multiple reflections between adjacent units to realize wide-angle insensitivity. The simulation results show that the unit can achieve good 1-bit phase control capability at 27 GHz under incidence angle ranging from 0° to 60°, and the insertion loss is lower than 0.8 dB.