Theory and application of reconfigurable intelligent surfaces with integrated sensing

实现具有高数据速率的不间断无线通信的一个主要挑战是由于传播环境（诸如建筑物的信号阻挡或各种表面的信号衍射）而引起的损耗。为了避免这些问题，使用可重构智能表面（RIS）的技术已经提出。RIS可以将反射信号重定向到目标用户，从而避免信号阻塞，减轻干扰或提高安全性。然而，设计期望的传播环境需要关于重要参数的知识，例如在RIS处可用的用户或发射机的方向。为了满足这一需求，本项目将开发一种新型的混合可重构智能表面（HRIS）。HRIS将被设计为感测整个表面上的入射波，推断相关信息，例如用户和发射机的方向，并相应地重新配置其反射模式。通过开发HRIS，该项目为实现真正智能和自主的传播环境铺平了道路。该项目还研究了HRIS能够以高空间分辨率感知环境的其他机会，例如为环境感知的家庭和建筑物或威胁检测成像对象。该研究项目由一个全面的教育计划补充，以吸引研究生和本科生设计元表面和HRIS，开发压缩传感技术，并设计智能电磁环境。该项目还包括几个本科生主导的努力，他们将学习使用HRIS来跟踪设备，并为它们提供用于无线电力传输（WPT）的聚焦光束。由此产生的自适应WPT演示将用于电磁研究和无线通信和传感的新兴趋势的主题的互动研讨会，以及在outreach events.This研究项目将概述HRIS的设计和实验演示其在典型的无线通信设置的实用程序。因此，它将做出创新性的贡献，包括1）设计一种新的超表面，允许对入射波进行可重构的反射和感测，2）开发和实验验证用于仅使用几个接收单元以高空间分辨率压缩感测传播环境的新算法，3）智能自适应通信链路，其中HRIS检测发射机和用户并相应地变换其反射模式，以及4）新成像配置的开发和实验验证，其中散射的无线通信信号（机会的信号）该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的评估被认为是值得支持的。影响审查标准。

One major challenge in achieving uninterrupted wireless communications with high data rate is the loss due to propagation environment, such as signal blockage by buildings or signal diffraction by various surfaces. To circumvent these issues, the technique of using reconfigurable intelligent surfaces (RIS) has been proposed. RIS can redirect reflected signals toward intended users, thus avoiding signal blockage, mitigating interference, or increasing security. Engineering the desired propagation environment, however, requires knowledge about important parameters such as the directions of the users or transmitters to be available at the RIS. To address this need, this project will develop a new type of hybrid reconfigurable intelligent surfaces (HRIS). The HRIS will be designed to sense the incident waves on the entire surface, deduce relevant information, such as the directions of users and transmitters, and reconfigure their reflection patterns accordingly. By developing the HRIS, this project paves the way for the implementation of a truly smart and autonomous propagation environment. This project also examines other opportunities that can be enabled by the HRIS to sense the environment with high spatial resolution, such as imaging objects for context-aware homes and buildings or threat detection. The research project is complemented by a comprehensive educational plan to engage graduate and undergraduate students in designing metasurfaces and HRIS, developing compressive sensing techniques, and devising intelligent electromagnetic environments. This project also includes several undergraduate-led efforts where they will learn to use the HRIS to track devices and provide them with focused beams for wireless power transfer (WPT). The resulting adaptive WPT demonstrations will be used in interactive workshops on topics of electromagnetic research and emerging trends in wireless communications and sensing, as well as at outreach events.This research project will outline the design of HRIS and experimentally demonstrate their utility in typical wireless communications settings. It will thus make innovative contributions including 1) the design of a novel metasurface that allows for reconfigurable reflection and sensing of the incident wave, 2) the development and experimental validation of novel algorithms for compressive sensing of the propagation environment with high spatial resolution using only a few receiving units, 3) a smart adaptive communications link where the HRIS detects the transmitter and users and transform its reflection patterns accordingly, and 4) development and experimental validation of novel imaging configurations where the scattered wireless communications signals (signals of opportunities) are collected by the HRIS and processed to retrieve reflectivity maps.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.