AI 中文总结
研究提出用于单射频链无源多目标DOA估计的紧凑型可重构天线，由加载PIN二极管的扇形圆形贴片构成，通过切换二极管状态实现频率和辐射图重构，结合虚拟空间采样与频率分集实现DOA估计，为ISAC系统提供高效传感方案。
AI 中文摘要
本文提出了一种紧凑且硬件高效的频率和辐射方向图可重构天线（FPRA），用于使用单个接收射频链的无源多目标到达方向（DOA）估计。该天线由加载16个PIN二极管的扇形圆形贴片组成。通过切换二极管状态，可移动贴片上的电流集中边界，实现工作频率和辐射方向图的重构。单个接收射频链下，该天线实现了-40度到40度的波束扫描，并在S和C波段提供多个工作频率。基于这些可重构观测状态，利用辐射方向图切换模拟传统天线阵列的空间采样，多频率观测引入相位分集以降低来自同一发射机照射的多个无源目标回波之间的相关性。实验结果表明，虚拟空间采样和频率分集相结合，无需传统天线阵列或多个接收射频链即可实现无源多目标DOA估计。所提出的FPRA为未来的集成传感与通信（ISAC）系统提供了一种紧凑且硬件高效的传感解决方案。
英文摘要
This work proposes a compact and hardware-efficient frequency- and radiation-pattern-reconfigurable antenna (FPRA) for passive multi-target direction-of-arrival (DOA) estimation using a single receive RF chain. The antenna consists of a sectorized circular patch loaded with 16 PIN diodes. By switching the diode states, the current-concentration boundary on the patch is shifted, enabling reconfiguration of both the operating frequency and radiation pattern. With a single receive RF chain, the proposed antenna achieves beam scanning from -40 degrees to 40 degrees and provides multiple operating frequencies across the S- and C-bands. Based on these reconfigurable observation states, radiation-pattern switching is used to emulate the spatial sampling of a conventional antenna array, while multi-frequency observations introduce phase diversity to reduce the correlation among echoes from multiple passive targets illuminated by the same transmitter. Experimental results demonstrate that the combined virtual spatial sampling and frequency diversity enable passive multi-target DOA estimation without a conventional antenna array or multiple receive RF chains. The proposed FPRA offers a compact and hardware-efficient sensing solution for future integrated sensing and communication (ISAC) systems.
Comments10 pages, 15figures
