大规模MIMO LEO卫星通信系统上行链路的信道估计  

Channel Estimation for Massive MIMO LEO Satellite Communication Systems

作　　者：雷芳[1] 侯康宁 莫刘燕 LEI Fang;HOU Kangning;MO Liuyan(School of Communication and Information Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)

机构地区：[1]重庆邮电大学通信与信息工程学院,重庆400065

出　　处：《小型微型计算机系统》2025年第2期424-429,共6页Journal of Chinese Computer Systems

基　　金：重庆市自然科学基金面上项目(cstc2021jcyj-msxmX0454)资助。

摘　　要：本文利用非地面网络抽头延迟线(NTN-TDL)模型建立低轨(LEO)卫星通信系统并引入了大规模MIMO技术,信道模型由确定性视距路径(LoS)和空间相关的随机非视距路径(NLoS)组成,使其信道服从空间相关的莱斯衰落.通过推导出该模型的最小均方误差(MMSE)、线性最小均方误差(LMMSE)和最小二乘(LS)信道估计的统计特性及其估计值,并使用这些估计值进行最大比合并(MRC)和预编码来补偿衰落的影响,计算出具有严格封闭形式的上行频谱效率表达式并评估了系统性能.仿真结果显示在具有空间相关的莱斯衰落环境下的低轨卫星系统比瑞利衰落环境下的低轨卫星系统的频谱效率更高并且使用MMSE估计器时的频谱效率最高,随着天线数量的增加系统性能的差距也更明显.In this paper,a LEO satellite communication system is established using the non-terrestrial network tap delay line(NTN-TDL)model and massive MIMO technology is introduced,that channel model consists of deterministic line-of-sight paths(LoS)and spatially related random non-line-of-sight paths(NLoS)that make it channel with space-related Rician fading.By deducing the statistical properties of the model′s minimum mean square error(MMSE),linear least mean square error(LMMSE)and least square(LS)channel estimates,and using these estimates for maximum ratio merging(MRC)and precoding to compensate for fading effects,the upstream spectral efficiency expression with strict closed form is calculated and the system performance is evaluated.Simulation results show that LEO satellite systems with space-related Rician fading environments are more spectrally efficient than Rayleigh fading environments,with the highest spectral efficiency when using MMSE estimators,and the difference in system performance becomes more pronounced as the number of antennas increases.

关 键 词：低轨卫星 大规模MIMO 信道估计 频谱效率 

分 类 号：TN927[电子电信—通信与信息系统]