Reconfigurable Intelligent Surface for NLOS Integrated Sensing and Communications

Reconfigurable intelligent surface (RIS) and inte-grated sensing and communication (ISAC), as two key potential technologies for future sixth generation (6G) wireless commu-nication networks, are jointly studied in this paper. A novel RIS-assisted ISAC system is proposed for the non-line-of-sight (NLOS) communication scenario, where the base station (BS) can simultaneously communicate with the target and estimate its distance and velocity. The RIS can not only provide the line-of-sight (LOS) path for radar sensing, but also improve the quality of communications by concentrating signal power on the target. The maximum likelihood estimation scheme is designed to estimate the distance and velocity. Furthermore, the communication performance of the proposed scheme is evaluated in term of data rate. Simulation results indicate that the proposed joint system can estimate the distance and velocity of the target well, and concurrently achieve required data rate.