An Experimental Proof of Concept for Sensing Using Hybrid Reconfigurable Intelligent Surfaces

This paper presents experimental proof-of-concept of a hybrid reconfigurable intelligent surface (HRIS) that can detect incident angles of arrivals (AoAs). Reconfigurable intelligent surfaces (RISs) can improve wireless communication by reflecting the incident signal in prescribed directions. This operation, however, requires knowledge about the intended transmitter and users (e.g., their AoAs) to be available at RISs. To achieve this operation without requiring extra feedback loops or complicated channel sensing algorithms, a sensing mechanism needs to be introduced into RISs. To address this challenge, we have designed HRISs that can couple a small portion of the incident signal on a few elements of the HRIS to be used for sensing purposes. We will outline and experimentally demonstrate a compressive sensing algorithm to utilize measurements at these few sparse sampling locations for detecting AoA. The proposed HRIS can be used to implement smart and autonomous wireless communication networks, wireless power transfer, and sensing systems.