可重构智能表面辅助近场通信感知一体化系统基于嵌套张量的同时定位与通信方法  

Nested Tensor-based Simultaneous Localization and Communication Method for RIS-assisted Near-field Integrated Sensing And Communication Systems

作　　者：罗欣 杜建和 张耀[2] 陈远知[1] 关亚林[1] LUO Xin;DU Jianhe;ZHANG Yao;CHEN Yuanzhi;GUAN Yalin(School of Information and Communication Engineering,Communication University of China,Beijing 100024,China;School of Artificial Intelligence,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]中国传媒大学信息与通信工程学院,北京100024 [2]北京邮电大学人工智能学院,北京100876

出　　处：《电子与信息学报》2025年第4期979-990,共12页Journal of Electronics & Information Technology

基　　金：国家重点研发计划(2022YFB3904603);国家自然科学基金(62471444,U2441236)。

摘　　要：可重构智能表面(RIS)因其能够智能配置无线传输环境而成为增强通信和感知的革新技术。随着RIS孔径的增加,电磁场特性发生根本性变化,近场范围扩大。与远场通信和感知不同,近场通信和感知需要考虑更为复杂的信道结构特性,这使得RIS辅助的毫米波系统在近场通信和感知方面更具挑战。基于此,该文研究一种RIS辅助通信感知一体化(ISAC)的近场传输系统。首先,利用所考虑的ISAC场景的多维度资源和Khatri-Rao空时编码方法,将接收到的ISAC信号构造为4阶嵌套张量。然后,利用嵌套张量的代数结构和对近场信道模型的2阶菲涅耳近似,设计一种基于嵌套张量的同时定位和通信方案,在不发送专用导频的情况下实现近场环境散射点和用户定位以及信息符号检测。仿真结果表明,提出的方案具有较好的ISAC性能并优于现有方案。此外,即使是在高阶调制情况下,所提方案也有良好的定位精度和的误码率性能。Objective As wireless communication technology advances,sensing and communication systems are shifting toward higher frequency bands,larger antenna arrays,and miniaturization.This integration of hardware architecture,channel characteristics,and signal processing enables wireless infrastructure to support environmental sensing in addition to communication.Technologies such as millimeter-wave communication,Reconfigurable Intelligent Surface(RIS),and Integrated Sensing And Communication(ISAC)facilitate this development.Although extensive research has examined RIS applications in ISAC systems,expanding the RIS aperture fundamentally alters electromagnetic field characteristics,extending the near-field range.Unlike farfield scenarios,near-field communication and sensing exhibit more complex channel structures,posing challenges for RIS-assisted millimeter-wave systems.To address these challenges,this study proposes an ISAC framework and develops a nested tensor-based Simultaneous Localization And Communication(SLAC)scheme.This approach localizes scattering points and users while detecting information symbols in near-field environments,eliminating the need for dedicated pilot signals.Methods First,a near-field spherical wave transmission model is established.To mitigate the complexity introduced by spatial path variations across reflection units,a channel model based on the second-order Taylor approximation is derived,incorporating distance,direction of arrival,and angle of arrival.Next,to fully utilize the time redundancy of Khatri-Rao Space-Time(KRST)coding,the received signal is formulated as a nested tensor model comprising outer and inner PARAFAC tensors,enabling the development of a nested tensor-based SLAC scheme.For the outer PARAFAC tensor,an Alternating Least Squares(ALS)algorithm is employed for channel matrix estimation and information symbol detection.For the inner PARAFAC model,a two-stage algorithm is used for channel parameter estimation and User Equipment(UE)and scatterer localization.The Minimum Descri

关 键 词：通信感知一体化 张量 可重构智能表面 近场 毫米波 

分 类 号：TN911.7[电子电信—通信与信息系统]