摘要
大规模MIMO系统中基站(BS)端天线数量很大,用于下行信道估计的导频开销将占用很多系统资源,尤其是在FDD模式下。为了减少导频开销,文中提出一种信道矩阵拆分方案,即利用多用户信道间的空间相关性将角域变换下的信道矩阵拆分为两个更加稀疏的信道矩阵,然后采用压缩感知(CS)技术分别恢复出这两部分信道,最后把两部分信道矩阵相加即得到完整的信道估计。不同于传统的信道估计方案,多个用户(UE)端接收到来自BS的导频信号后不在本地进行信道估计,而是把接收到的信号直接反馈给BS,在BS端进行信道的联合恢复。仿真结果表明,所提方案能够有效降低信道估计所需导频开销,同时保证良好的信道估计性能。
Massive multiple-input-multiple-output（MIMO） system employs a large number of antennas at the base station（BS）,so the overwhelming pilot overhead for the downlink channel estimation will consume a large portion of radio resources,especially for FDD mode. To reduce the pilot overhead,a separation scheme for the channel matrix is proposed. The spatial correlation among multi-user channel matrixes in virtual angular domain is exploited to separate the channel matrix into two parts. Then,compressed sensing（CS） theory is used to estimate the two parts of the channel matrix and the estimated channel matrix can be obtained. Moreover,different from conventional methods of channel estimation,UEs feedback the received symbols from the BS to the BS directly,and the channel state information（CSI） recovery is performed at the BS jointly. Simulation results show that the proposed scheme can effectively reduce the pilot overhead of the channel estimation,thus guaranteeing the performance estimation.
作者
马汝奔
傅友华
王海荣
MA Ruben;FU Youhua;WANG Hairong(College of Electronic and Optical Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210023,China;College of Telecommunications ＆ Information Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210003,China)
出处
《南京邮电大学学报（自然科学版）》
北大核心
2018年第5期56-62,共7页
Journal of Nanjing University of Posts and Telecommunications：Natural Science Edition
基金
国家自然科学基金(61302101)
江苏省自然科学基金(BK20130874)
射频集成与微组装技术国家地方联合工程实验室开放基金(KFJJ20170304)
南京邮电大学校级科研基金(NY218009)资助项目
关键词
多用户大规模MIMO系统
FDD
稀疏信道估计
压缩感知
multi-user massive multiple-input-multiple-output （MIMO） system
FDD
sparse channel es-timation
compressed sensing（CS）
