发表机构
Beihang University; Queen’s University Belfast（北京航空航天大学; 贝尔法斯特女王大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对捏天线系统支持的安全集成感知与通信，本文提出双时间尺度优化框架，结合多/单波导场景设计波束成形方案，可准确跟踪窃听者状态并提升保密速率。
AI 中文摘要
本文提出了一种新型双时间尺度优化框架，用于捏天线系统（PASS）支持的安全集成感知与通信（ISAC）。具体而言，配备捏天线（PA）的基站（BS）向合法用户传输信号，同时存在窃听者（Eve），基站利用泄漏同轴电缆（LCX）接收回波信号以跟踪Eve的移动状态，即位置和速度。考虑到实际的PA激活开销，捏波束成形和基带处理分别在大、小时间尺度上进行优化。本文首先考虑多波导场景，其中基站可同时传输人工噪声与通信信号，用于干扰和感知目的。构建联合基带与捏波束成形设计问题以最大化平均保密速率。为解决该问题，首先采用交替优化算法，结合预测的Eve移动状态联合优化捏波束成形和基带波束成形；在确定PA位置后，利用实时回波信号处理得到的精细Eve状态更新基带波束成形。随后考虑单波导场景，由于单波导最多承载一个独立数据流，本文提出了通信与感知阶段分离的ISAC框架，并将多波导场景下的逐元素算法扩展以求解捏波束成形问题。数值结果表明：1）在多波导和单波导场景下，所提双时间尺度框架均可准确跟踪Eve的速度和位置；2）与传统多天线基准相比，PASS实现了更优的保密速率。
英文摘要
A novel two-timescale optimization framework is proposed for pinching-antenna systems (PASS)-enabled secure integrated sensing and communications (ISAC). Specifically, a base station (BS) equipped with pinching antennas (PAs) transmits signals to a legitimate user under the existence of an eavesdropper (Eve), while employing leaky coaxial cables (LCXs) for receiving echo signals to track Eve's mobility states, i.e., locations and velocities. Considering the practical PAs activation overhead, the pinching beamforming and baseband processing are optimized in the large and small timescales, respectively. The multiple-waveguide scenario is first considered, where the BS can transmit the artificial noise together with communication signals for both jamming and sensing purposes. A joint baseband and pinching beamforming design problem is formulated to maximize the average secrecy rate. To address this problem, an alternating optimization algorithm is first invoked for jointly optimizing the pinching and baseband beamforming with predicted Eve's mobility states. With determined PAs positions, the baseband beamforming is updated with refined Eve's states obtained from real-time echo signal processing. The single-waveguide scenario is then considered. Since a single waveguide carries at most one independent data stream, an ISAC framework with separate communication and sensing phases is proposed. The element-wise algorithm proposed for the multiple-waveguide scenario is extended to solve the resultant pinching beamforming problem. Numerical results demonstrate that: 1) Eve's velocities and positions can be accurately tracked with the proposed two-timescale framework in both multiple- and single-waveguide scenarios; and 2) PASS achieves superior secrecy rate compared to conventional multiple-antenna benchmarks.
