Reconfigurable Intelligent Surfaces Enabling Passive High-Speed Switching

Abstract

In recent years, metasurfaces have been explored for various applications, including reconfigurable intelligent surfaces (RISs). RISs are expected to extend the coverage of nextgeneration communication systems by altering the reflection angle of incident waves in an artificial manner. However, conventional RISs require external direct-current (DC) supplies to switch the reflection angles, which severely limits the relocation of RISs. In contrast, waveformselective metasurfaces have been reported to control the electromagnetic characteristics without any external DC supply by using the transient response of classical DC circuits. However, this response was relatively slow due to the nature of the circuit, more specifically its time constant. For this reason, we propose a new class of waveform-selective metasurfaces composed of a fast-switching circuit component and integrate them with RIS design. In this study, we evaluate the switching response numerically and experimentally.