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arXiv · 2203.00265

Joint Beamforming and Reflection Design for RIS-assisted ISAC Systems

Rang Liu·Ming Li·A. Lee Swindlehurst
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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 single-output (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.

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Rang Liu, Ming Li, A. Lee Swindlehurst. 2022-03-01. Joint Beamforming and Reflection Design for RIS-assisted ISAC Systems. https://doi.org/10.23919/eusipco55093.2022.9909807

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