Joint Beamforming and Reflection Design for RIS-assisted ISAC Systems

Abstract

In this paper, we investigate the potential of employing reconfigurable intelligent surface (RIS) in integrated sensing and communication (ISAC) systems. In particular, we consider an RIS-assisted ISAC system in which a multi-antenna base station (BS) simultaneously performs multi-user multi-input singleoutput (MU-MISO) communication and target detection. We aim to jointly design the transmit beamforming and receive filter of the BS, and the reflection coefficients of the RIS to maximize the sum-rate of the communication users, while satisfying a worst-case radar output signal-to-noise ratio (SNR), the transmit power constraint, and the unit modulus property of the reflecting coefficients. An efficient iterative algorithm based on fractional programming (FP), majorization-minimization (MM), and alternative direction method of multipliers (ADMM) is developed to solve the complicated non-convex problem. Simulation results verify the advantage of the proposed RIS-assisted ISAC scheme and the effectiveness of the developed algorithm.

Beyond 5G RIS mmWave Systems: Where Communication and Localization Meet

“…In particular, SLAC is limited to bi-static operation (communication and sensing and localization of connected devices), while ISAC also considers monostatic operation. While the focus of this paper is limited to SLAC, RIS is also expected to play an important role in ISAC, as shown in, e.g., [5]- [8].…”