This paper presents a reconfigurable intelligent sensing surface (RISS) that combines passive and active elements to achieve simultaneous reflection and direction of arrival (DOA) estimation tasks. By utilizing DOA information from the RISS instead of conventional channel estimation, the pilot overhead is reduced and the RISS becomes independent of the hybrid access point (HAP), enabling efficient operation. Specifically, the RISS autonomously estimates the DOA of uplink signals from single-antenna users and reflects them using the HAP's slowly varying DOA information. During downlink transmission, it updates the HAP's DOA information and designs the reflection phase of energy signals based on the latest user DOA information. The paper includes a comprehensive performance analysis, covering system design, protocol details, receiving performance, and RISS deployment suggestions. We derive a closed-form expression to analyze system performance under DOA errors, and calculate the statistical distribution of user received energy using the moment-matching technique. We provide a recommended transmit power to meet a specified outage probability and energy threshold. Numerical results demonstrate that the proposed system outperforms the conventional counterpart by 2.3 dB and 4.7 dB for Rician factors $\kappa_h=\kappa_G=1$ and $\kappa_h=\kappa_G=10$, respectively.

翻译：本文提出了一种结合无源和有源元件的可重构智能感知表面（RISS），能够同时实现信号反射与波达方向（DOA）估计任务。通过利用RISS获取的DOA信息替代传统信道估计方法，可降低导频开销，并使RISS独立于混合接入点（HAP）工作，从而实现高效运行。具体地，RISS自主估计单天线用户上行链路的DOA，并利用HAP缓慢变化的DOA信息反射信号；在下行链路传输中，它更新HAP的DOA信息，并基于最新的用户DOA信息设计能量信号的反射相位。本文对系统进行了全面的性能分析，包括系统设计、协议细节、接收性能及RISS部署建议。我们推导了存在DOA误差时系统性能的闭式表达式，并采用矩匹配技术计算用户接收能量的统计分布。通过满足指定中断概率与能量阈值，给出了推荐发射功率。数值结果表明，在莱斯因子分别为$\kappa_h=\kappa_G=1$和$\kappa_h=\kappa_G=10$时，所提系统性能较传统方案分别提升2.3 dB和4.7 dB。