协作多小区大规模MIMO系统中基于协方差的活跃设备检测  

Covariance-Based Activity Detection in Cooperative Multi-Cell Massive MIMO

作　　者：王子岳 刘亚锋 王兆瑞 WANG Ziyue;LIU Yafeng;WANG Zhaorui(LSEC,ICMSEC,AMSS,Chinese Academy of Sciences,Beijing 100190,China;FNii and SSE,The Chinese University of Hong Kong,and Guangdong Provincial Key Laboratory of Future Networks of Intelligence,Shenzhen 518172,China)

机构地区：[1]中国科学院数学与系统科学研究院,计算数学与科学工程计算研究所,科学与工程计算国家重点实验室,北京100190 [2]深圳市未来智联网络研究院,香港中文大学(深圳)理工学院,广东省未来智联网络重点实验室,广东深圳518172

出　　处：《移动通信》2025年第1期122-129,共8页Mobile Communications

基　　金：国家自然科学基金委员会“5G和后5G通信系统设计中的两类优化问题和方法研究”(12371314);国家自然科学基金委员会,创新研究群体项目“最优化计算方法、理论及其应用”(12021001);国家基金委基础科学中心项目“流形上的几何、分析与计算”(12288201);河套深港科技创新合作区基础研究项目(HZQB-KCZYZ-2021067)。

摘　　要：聚焦于多小区大规模多输入多输出(MIMO,Multiple-Input Multiple-Output)系统中基于协方差的活跃设备检测问题。在该系统中,活跃设备向多个基站传输其导频序列,基站根据接收到的信号协作地检测活跃设备。在单小区场景下,基于协方差的活跃设备检测模型的尺度定律(Scaling Law)已在文献中得到广泛分析,旨在分析基于协方差的活跃设备检测模型在多小区大规模MIMO系统中的尺度定律。具体来说,在衰落信道的路径损耗指数γ>2的情况下,建立了多小区系统中的二次尺度定律。这一结果表明,在多小区大规模MIMO系统中,当天线数趋于无穷大时,每个小区能够正确检测出的活跃设备数量的最大值随导频序列的长度呈二次方增长,且随着小区数量呈对数减少。此外,除了分析由球面上均匀分布生成的导频序列的尺度定律,还建立了由有限字母表生成的导频序列的尺度定律,这类序列更易于生成和存储。最后,提出了两种高效的加速坐标下降(CD,Coordinate Descent)算法来求解活跃设备检测问题,它们都具有收敛性保证。第一种算法通过非精确坐标更新策略来降低CD算法的复杂度;第二种算法利用积极集选择策略避免了CD算法中不必要的计算。仿真结果表明,所提出的算法在计算效率和检测错误概率方面表现出色。This paper focuses on the covariance-based activity detection problem in a multi-cell massive multiple-input multiple-output(MIMO)system.In this system,active devices transmit their signature sequences to multiple base stations(BSs),and the BSs cooperatively detect the active devices based on the received signals.While the scaling law for the covariance-based activity detection in the single-cell scenario has been extensively analyzed in the literature,this paper aims to analyze the scaling law for the covariance-based activity detection in the multi-cell massive MIMO system.Specifically,this paper demonstrates a quadratic scaling law in the multi-cell system,under the assumption that the path-loss exponent of the fading channelγ>2.This finding shows that,in the multi-cell massive MIMO system,the maximum number of active devices that can be correctly detected in each cell increases quadratically with the length of the signature sequence and decreases logarithmically with the number of cells(as the number of antennas tends to infinity).Moreover,in addition to analyzing the scaling law for the signature sequences randomly and uniformly distributed on a sphere,the paper also establishes the scaling law for signature sequences based on a finite alphabet,which are easier to generate and store.Finally,this paper proposes two efficient accelerated coordinate descent(CD)algorithms with a convergence guarantee for solving the device activity detection problem.The first algorithm reduces the complexity of CD by using an inexact coordinate update strategy.The second algorithm avoids unnecessary computations of CD by using an active set selection strategy.Simulation results show that the proposed algorithms exhibit excellent performance in terms of computational efficiency and detection error probability.

关 键 词：加速坐标下降算法 协作活跃设备检测 大规模随机接入 多小区大规模多输入多输出 尺度定律分析 导频序列 

分 类 号：TN929.5[电子电信—通信与信息系统]