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arXiv · 2606.22897

Adaptive Joint Beamforming and Fluid Antenna System Design for 6G ISAC

Abstract

Fixed-Position Antennas (FPAs) are constrained by static physical topologies and struggle to adapt to rapidly varying wireless environments. By dynamically reconfiguring the antenna positions, Fluid Antenna Systems (FASs) introduce additional spatial Degrees of Freedom (DoF) for wireless optimization. This paper investigates the joint optimization of Fluid Antenna System (FAS) topology reconfiguration and active beamforming for mobile Integrated Sensing and Communication (ISAC) systems. To enable real-time decision making, an end-to-end optimization framework based on the Soft Actor-Critic (SAC) algorithm is proposed. Simulation results show that the proposed scheme achieves an online inference latency of only 4 ms. Compared to the widely used alternating optimization, it improves communication performance by 42%. Moreover, it achieves performance comparable to the SCA-SDR benchmark while requiring 57% fewer antennas, demonstrating superior hardware efficiency.

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BibTeXRIS

Haoyu Quan, Junhui Zhao, Dongming Wang. 2026-06-22. Adaptive Joint Beamforming and Fluid Antenna System Design for 6G ISAC. https://arxiv.org/abs/2606.22897

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