Integrated sensing and communication (ISAC) has been recognized as one of the key technologies capable of simultaneously improving communication and sensing services in future wireless networks. Moreover, the introduction of recently developed movable antennas (MAs) has the potential to further increase the performance gains of ISAC systems. Achieving these gains can pose a significant challenge for MA-enabled ISAC systems operating in the near-field due to the corresponding spherical wave propagation. Motivated by this, in this paper we maximize the weighted sum rate (WSR) for communication users while maintaining a minimal sensing requirement in an MA-enabled near-field ISAC system. To achieve this goal, we propose an algorithm that optimizes the sensing receive combiner, the communication precoding matrices, the sensing transmit beamformer and the positions of the users' MAs in an alternating manner. Simulation results show that using MAs in near-field ISAC systems provides a substantial performance advantage compared to near-field ISAC systems with only fixed antennas. Additionally, we demonstrate that the highest WSR is obtained when larger weights are allocated to the users placed closer to the BS, and that the sensing performance is significantly more affected by the minimum sensing signal-to-interference-plus-noise ratio (SINR) threshold compared to the communication performance.

翻译：集成感知与通信（ISAC）已被公认为未来无线网络中能够同时提升通信与感知服务能力的关键技术之一。此外，近期发展的移动天线（MAs）技术有望进一步增加ISAC系统的性能增益。对于工作在近场区域的移动天线使能ISAC系统而言，实现这些增益会因相应的球面波传播而面临重大挑战。基于此，本文在移动天线使能近场ISAC系统中，以维持最小感知需求为约束条件，最大化通信用户的加权和速率（WSR）。为实现该目标，我们提出一种交替优化感知接收合并器、通信预编码矩阵、感知发射波束赋形器以及用户移动天线位置的算法。仿真结果表明，相比仅采用固定天线的近场ISAC系统，在近场ISAC系统中使用移动天线可提供显著性能优势。此外，我们证明当距离基站较近的用户被分配更大权重时能获得最高WSR，且与通信性能相比，感知性能受最小感知信干噪比（SINR）阈值的影响更为显著。