基于张量分解和流形优化的双IRS辅助毫米波MIMO系统信道估计  

Channel estimation for double IRS-assisted millimeter wave MIMO systems based on tensor decomposition and manifold optimization

作　　者：冯凯辉 刘陈[1] 黄钲 宋云超 高润勤 FENG Kaihui;LIU Chen;HUANG Zheng;SONG Yunchao;GAO Runqin(School of Electronic and Optical Engineering&School of Flexible Electronics(Future Technology),Nanjing University of Posts and Telecommunications,Nanjing 210023,China)

机构地区：[1]南京邮电大学电子与光学工程学院、柔性电子(未来技术)学院,江苏南京210023

出　　处：《物联网学报》2024年第4期119-128,共10页Chinese Journal on Internet of Things

基　　金：国家自然科学基金资助项目(No.62101282)。

摘　　要：针对双智能反射面(IRS,intelligent reflecting surface)辅助毫米波多入多出(MIMO,multiple-input multiple-output)系统信道估计问题,提出一种基于张量分解和流形优化的信道估计方案。首先,利用接收信号的高维特征构建张量模型,并基于张量的Tucker2分解形式给出信道估计问题的目标函数;其次,利用交替优化理论将信道估计问题拆分为多个子问题,为双IRS场景下用户与IRS、双IRS之间和IRS与基站之间信道的分别估计提供了可行方案;最后,考虑毫米波信道本身的低秩特性,将各个信道估计子问题转化为在复定秩矩阵流形上的优化问题,利用复定秩流形优化求解秩受限优化问题的优势,提出基于流形优化的交替信道估计方案。不同于传统方案,所提方案考虑了毫米波信道的低秩特性,对信道进行了准确描述,并应用流形优化理论有效处理定秩约束,提高了信道估计精度。仿真结果表明,在不同场景下所提方案的估计性能均优于现有参考方案。The issue of channel estimation for a double intelligent reflecting surface(IRS)assisted millimeter wave multiple-input multiple-output(MIMO)system was addressed and a channel estimation scheme based on tensor decomposition and manifold optimization was proposed.Specifically,a tensor model was constructed based on the highdimensional features of received signals,and the objective function of the channel estimation problem was formulated based on the Tucker2 decomposition of the tensor.Then,the channel estimation problem was decomposed into multiple sub-problems using alternating optimization theory,providing feasible solutions for estimating the channel of each hop in the double IRS scenario.Finally,considering the low-rank characteristics of the millimeter wave channel itself,each channel estimation sub-problem was transformed into an optimization problem on the complex fixed-rank matrix manifold,and a manifold optimization-based alternating channel estimation scheme was proposed by leveraging the advantages of fixed-rank manifold optimization in solving rank-constrained optimization problems.Unlike traditional schemes,the proposed scheme takes into account the low-rank characteristics of millimeter wave channels,accurately describes the channels,and effectively handles fixed-rank constraints using manifold optimization theory,thus improving the accuracy of channel estimation.Simulation results show that the proposed channel estimation scheme outperforms existing reference schemes in terms of estimation performance in different scenarios.

关 键 词：毫米波MIMO系统 双智能反射面 信道估计 流形优化 张量分解 

分 类 号：TN928[电子电信—通信与信息系统]