Movable Antenna-enabled RIS-aided Integrated Sensing and Communication

TL;DR

This paper introduces a movable antenna-enabled RIS system for integrated sensing and communication, optimizing beamforming, RIS coefficients, and antenna positions to improve performance in dead zones.

Contribution

It proposes a joint optimization framework for movable antennas and RIS in ISAC systems, employing advanced algorithms to enhance wireless sensing and communication.

Findings

MA and RIS-aided system outperforms fixed antenna systems

Movable antennas reduce user channel similarity

System enhances channel gain and sensing performance

Abstract

In this paper, we investigate a movable antenna (MA)-aided integrated sensing and communication (ISAC) system, where a reconfigurable intelligent surface (RIS) is employed to enhance wireless communication and sensing performance in dead zones. Specifically, this paper aims to maximize the minimum beampattern gain at the RIS by jointly optimizing beamforming matrix at the base station (BS), the reflecting coefficients at the RIS and the positions of the MAs, subject to signal-to-interference-plus-noise ratio (SINR) constraint for the users and maximum transmit power at the BS. To tackle this non-convex optimization problem, we propose an alternating optimization (AO) algorithm and employ semidefinite relaxation (SDR), sequential rank-one constraint relaxation (SRCR) and successive convex approximation (SCA) techniques. Numerical results indicate that the MA and RIS-aided ISAC system outperforms conventional fixed position antenna (FPA) and RIS-aided systems. In addition, the application of MAs can reduce the similarity of user channels and enhance channel gain in the ISAC system.