基于随机矩阵理论的大规模MIMO系统窃听用户检测  

Active eavesdropper detection based on large dimension random matrix theory for massive MIMO systems

作　　者：刘铭 徐丽 王晓懿 陈佳奇 LIU Ming;XU Li;WANG Xiaoyi;CHEN Jiaqi(School of Computer and Information Technology,Beijing Jiaotong University,Beijing 100044,China;China Railway Fifth Survey and Design Institute Group Co.,Ltd.,Beijing 102699,China;School of Mathematics,Harbin Institute of Technology,Harbin 150000,China)

机构地区：[1]北京交通大学计算机与信息技术学院,北京100044 [2]中铁第五勘察设计院集团有限公司,北京102699 [3]哈尔滨工业大学数学学院,哈尔滨150006

出　　处：《北京交通大学学报》2020年第2期58-65,共8页JOURNAL OF BEIJING JIAOTONG UNIVERSITY

基　　金：国家自然科学基金(61971029)。

摘　　要：针对传统的利用信息论准则检测主动窃听用户方法的弊端,提出了适用于样本数目小于基站天线数目的检测主动窃听用户的算法.通过将线性收缩方法和子空间方法结合,有效地在小样本场景下进行主动窃听用户检测,而不产生额外的计算开销.提出利用大维随机矩阵理论获得对噪声方差更为精确的估计.同时采用线性收缩方法对样本协方差矩阵的特征值进行线性收缩,使其更好地拟合总体协方差矩阵,以提升小样本情况下的检测性能.最后利用子空间方法对线性收缩后的样本特征值进行检测,准确地检测是否存在主动窃听用户.蒙特卡洛仿真结果表明,结合大维随机矩阵理论与线性收缩的检测算法可以在小样本场景中有效检测主动窃听用户.According to the traditional method of using information theoretic approach to detect active eavesdropper,this paper proposes an algorithm for detecting active eavesdropper with a sample number smaller than the number of base station antennas.The proposed method combines the linear shrinkage method with the subspace method,and can detect active eavesdropper effectively when the number of samples is not large,without a significant increase of computational overhead.Specifically it proposes to employ the large-dimensional random matrix theory to obtain a more accurate estimate of noise variance.Linear shrinkage method is adopted to process the sample covariance matrix such that it can better fit the population covariance matrix and yield a better detection performance when the number of samples is not large.With the assistance of linearly shrinked sample covariance matrix,the subspace method is used to determine whether there exists active eavesdropper.The Monte Carlo simulation results show that the combination of large-dimensional random matrix theory and linear shrinkage detection algorithm can effectively detect the existence of the active eavesdropper when the number of samples is not large.

关 键 词：无线通信 大规模MIMO 主动窃听用户检测 随机矩阵理论 线性收缩 

分 类 号：TN92[电子电信—通信与信息系统]