一种基于空时相关的MIMO OFDM系统信道估计算法  

An Algorithm of Channel Estimation Based on Space-Time Correlation in MIMO OFDM System

作　　者：耿欣[1] 胡捍英[1] 敦亚南[1] 

机构地区：[1]信息工程大学信息工程学院,郑州450002

出　　处：《电信科学》2011年第11期84-89,共6页Telecommunications Science

基　　金：国家"十一五""863"计划重点项目"高频段无线通信基础技术研究开发与示范系统"子课题"高频段无线链路技术研究"基金资助项目(No.20090AA011504);国家重大专项"新一代宽带无线移动通信网"子课题"IMT-Advanced关键技术仿真平台开发"基金资助项目(No.2009ZX03003-008)

摘　　要：提出了一种基于空时相关的MIMO OFDM系统信道估计算法,该算法以时域最小二乘信道估计(TD-LS-CE)为初始估计,充分利用在接收端已知的空时相关性,通过最小化FIR窗内多符号平均意义上的信道估计均方误差(MSE),获得对初始信道估计进行空时滤波的最优权系数,并进一步利用奇异值分解的方法大大降低该信道估计算法的复杂度。最后仿真结果表明,在相同的条件下,该信道估计算法在MSE、BER方面优于传统滑动平均(MA)信道估计算法在其最佳窗长时的性能,且在一定条件下可逼近理想信道估计性能。此外,空时相关性的增强还可进一步改善该信道估计算法的性能。In this paper,an algorithm of channel estimation based on space-time correlation in MIMO OFDM systems is proposed,which adopts an LS channel estimation scheme of time domain for initial estimation and exploits full information of the space-time correlation known at the receiver.The optimal weight of the space-time filter for the initial estimation is obtained by minimizing the MSE of channel estimation in average sense of multiple symbols in the FIR window.Further,the complexity of the algorithm is greatly decreased by the SVD method.Finally,simulations show that this algorithm derived outperforms the conventional MA algorithm of channel estimation in the performances of the MSE and BER when the optimal length of the FIR window reaches under the same conditions.And at some conditions,the performance of the algorithm can approach the performance of the ideal channel estimation,and can be improved with the space-time correlation increased.

关 键 词：MIMO OFDM系统 时域最小二乘信道估计 空时相关 滑动平均 时域归一化均方误差 

分 类 号：TN948.14[电子电信—信号与信息处理]