Mutual Coupling-Aware Localization for RIS-Assisted ISAC Systems
Artikel i vetenskaplig tidskrift, 2025

Integrated sensing and communication (ISAC) is recognized as a promising approach to address the growing spectrum requirements for seamless sensing and communication. This paper investigates the deployment of reconfigurable intelligent surface (RIS) in ISAC systems under line-of-sight (LoS) obstructions, addressing the limited attention given to mutual coupling (MC) among RIS elements and its impact on localization performance. We tackle the joint estimation of the 3D location of a single-antenna user equipment (UE) and MC coefficients in challenging multipath and LoS-blocked environments. To enhance MC estimation, we extend our analysis to scenarios where signals from multiple UE locations are available, leveraging the stability of MC values over extended time intervals. Our methodology encompasses several key steps: first, we estimate the delay using the multiple signal classification (MUSIC) algorithm to mitigate multipath effects; second, we employ an efficient MC-unaware maximum likelihood (ML) approach for initial 2D angle-of-departure (2D-AOD) estimation; third, we propose a novel closed-form solution for the initial estimation of MC coefficients relying on a scattering matrix-based realistic MC modeling; and finally, we introduce a low-complexity alternating optimization algorithm for the joint refinement of the 2D-AODs and MC values. Simulation results demonstrate the effectiveness of the proposed method, outperforming classical MC-unaware ML techniques.

array imperfection

3D localization

mutual coupling

maximum likelihood

alternating optimization

angle of departure estimation

ISAC

RIS

Författare

Alireza Fadakar

University of Southern California

Musa Furkan Keskin

Chalmers, Elektroteknik, Kommunikation, Antenner och Optiska Nätverk

Hui Chen

Chalmers, Elektroteknik, Kommunikation, Antenner och Optiska Nätverk

Henk Wymeersch

Chalmers, Elektroteknik, Kommunikation, Antenner och Optiska Nätverk

IEEE Transactions on Cognitive Communications and Networking

23327731 (eISSN)

Vol. In Press

Ämneskategorier (SSIF 2025)

Kommunikationssystem

Telekommunikation

Signalbehandling

DOI

10.1109/TCCN.2025.3565541

Mer information

Senast uppdaterat

2025-05-09