Ultra-Reconfigurable VO 2 -Based Reflectarrays for 5G Applications

We present an ultra-reconfigurable reflectarray platform based on the insulator-to-metal transition property of VO 2 . A VO 2 layer is placed on a high-density micro-heater matrix consisting of pixels that can be switched on via electronic control. Controlling the pixels in this manner, heat can be transferred to the selected areas of the VO 2 layer and convert it to highly conductive metallic phase. This technique allows dynamically changing the shape of the reflection antenna surface with high speed. We numerically investigated the heat activated switching and RF reflection characteristics of a reflectarray designed for potential 5G applications operating in 32–86 GHz. It consists of heating pixels with the size of 100 × 100 um which can generate metallic VO 2 patches or arbitrary shapes with the same spatial resolution. Our analyses resulted in large phase range of ~310° and low loss between −0.14 dB to −0.18 dB. The proposed device can serve as a novel platform for ultra-reconfigurable reflectarrays and metasurfaces for various of RF applications in wide a spectral range.