面向移动用户的RIS波束追踪与覆盖增强技术  

RIS Beam Tracking and Coverage Enhancement Technology for Mobile Users

作　　者：呼和 费丹 韩福勇 张天乐 郑鹏 陈浩然 张思宇[1] 艾渤[2] HU He;FEI Dan;HAN Fuyong;ZHANG Tianle;ZHENG Peng;CHEN Haoran;ZHANG Siyu;AI Bo(School of Information and Communication Engineering,Beijing Information Science and Technology University,Beijing 102206,China;School of Electronic and information Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京信息科技大学信息与通信工程学院,北京102206 [2]北京交通大学电子信息工程学院,北京100044

出　　处：《信号处理》2024年第8期1460-1468,共9页Journal of Signal Processing

基　　金：中央高校基本科研业务费(2022JBZY018);国家自然科学基金(62301058);国防科技工业海洋防务技术创新中心创新基金(2021-40);江苏省前沿引领技术基础研究专项(BK20212002-3)。

摘　　要：智能超表面(Reconfigurable Intelligent Surface,RIS)技术因其能够灵活操控信道环境的电磁特性,一经出现就引起了学术界和工业界的广泛关注。目前对于RIS辅助无线通信系统的理论研究与实际测试以静止场景为主,缺乏移动场景的研究。而由于RIS反射波束较窄,存在着移动场景下RIS反射波束难以对准目标,导致覆盖增强效果较差的问题。针对此问题,本文创新性地结合了波达方向(Direction Of Arrival,DOA)估计理论与RIS覆盖增强技术,实现了针对移动用户的RIS波束追踪与覆盖增强,并在此基础上搭建了Sub 6G频段下RIS辅助的移动场景原型平台。此外,本文在实验室对比了不同速度下,发射端移动而接收端保持静止、接收端移动而发射端保持静止两种场景下,经RIS反射后的接收信号功率与信干噪比(Signal Interference plus Noise Ratio,SINR)值。实测结果表明,在两种实测动态场景下RIS编码前后的接收信号功率与SINR均有提升,证明RIS在移动场景下仍然具有较好的性能提升。本文的研究结果可对后续移动场景下RIS辅助通信提供数据支撑与可参考原型平台。Reconfigurable intelligent surface(RIS)technology has attracted extensive attention from academia and industry since its emergence owing to its ability to flexibly control the electromagnetic characteristics of the channel environment.Currently,the theoretical research and practical testing of RIS-assisted wireless communication systems are focusing on stationary scenarios,and studies on mobile scenarios are lacking.However,because of the narrow RIS reflected beam,the RIS reflected beam cannot easily aim at the target in mobile scenarios,resulting in a poor coverage enhancement effect.To address this limitation,this study introduces an innovative solution that synergistically combines the principles of direction-of-arrival estimation and RIS coverage enhancement techniques.This novel approach facilitates accurate RIS beam tracking for mobile users,ensuring consistent signal quality and coverage even in highly dynamic environments.Based on this conceptual breakthrough,we developed a prototype platform tailored for RISassisted communication within the sub-6G frequency spectrum.This platform serves as a practical testament to theoretical advancements,providing a tangible basis for further exploration and validation.To evaluate the performance of the proposed solution,we conducted a series of experiments within a controlled laboratory setting.These experiments were designed to assess the variations in received signal power and signal interference plus noise ratio(SINR)under two distinct conditions:scenarios where the transmitter is in motion relative to a stationary receiver and vice versa,across various speeds.The measured results show that the received signal power and SINR are improved before and after RIS coding in the two dynamic scenarios,proving that RIS still has scope for performance improvements in mobile communication scenarios.Our research results can provide data support and a reference prototype platform for RIS-assisted communication in future mobile communication scenarios.

关 键 词：智能超表面 波束追踪 覆盖增强 

分 类 号：TN929.5[电子电信—通信与信息系统]