| Title |
Joint Optimization of Beamforming, Active RIS, and Movable Antennas for Improving Integrated Sensing and Communication Performance |
| Authors |
신승석(Seungseok Sin) ; 김재혁(Jaehyeok Kim) ; 조인식(Insik Cho) ; 김태홍(Taehong Kim) ; 문상미(Sangmi Moon) ; 황인태(Intae Hwang) |
| DOI |
https://doi.org/10.5573/ieie.2026.63.3.11 |
| Keywords |
Alternating Optimization (AO); Integrated Sensing and Communication (ISAC); Joint Optimization; Majorization-Minimization (MM); Movable Antenna (MA); Reconfigurable Intelligent Surface (RIS); |
| Abstract |
In next-generation 6G wireless networks, Integrated Sensing and Communication (ISAC) has emerged as a key technology that combines communication and sensing functionalities within a unified framework. Meanwhile, Reconfigurable Intelligent Surfaces (RIS) and Movable Antennas (MA) are promising technologies for enhancing channel quality and spatial diversity. This paper considers an ISAC system that integrates an active RIS and MA, and proposes a joint optimization algorithm that maximizes radar sensing performance by simultaneously optimizing base station (BS) transmit beamforming, RIS reflection and amplification coefficients, and MA positions. The formulated problem is a non-convex optimization due to the strong coupling among the three variables. To tackle this, an Alternating Optimization (AO) framework is developed, where MM (Majorization?Minimization) and SCA (Successive Convex Approximation)-based SDP are used for BS beamforming, MM?SDR (Semidefinite Relaxation) is applied to active RIS optimization, and a first-order Taylor approximation-based SCA method is employed for MA positioning. The proposed algorithm ensures a monotonic increase of the surrogate function and stable convergence. Simulation results verify that combining MA and active RIS achieves significant Radar SINR improvements over conventional fixed-antenna and passive-RIS systems. This study demonstrates the effectiveness of the proposed Active RIS and MA-aided ISAC framework and provides insights for reliable and high-precision 6G system design. |