使用LMMSE接收机的V-BLAST系统容量和导频优化  

Capacity and training optimization for V-BLAST system with LMMSE receiver

作　　者：李强 李云洲[1] 周世东[1] 姚彦[1] 

机构地区：[1]清华大学电子工程系,清华信息科学与技术国家实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2008年第7期1116-1118,1122,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(90204001)

摘　　要：为了得到使用线性最小均方误差(LMMSE)接收机的空间复用系统(V-BLAST)在连续时变平衰落多天线信道环境中的容量,并分析信道估计误差对于LMMSE接收机输出信干噪比的影响,该文使用随机矩阵理论分析了以训练为基础的信道估计对于接收机性能的影响,得到了渐进表达的容量公式。仿真结果表明:在尺度受限的系统中,分析仍然有效。在得到容量解的基础上,进一步考虑了训练长度和训练间隔的优化,采用数值计算的方法得到了相应的优化结果,它们是信道相关时间和信噪比的函数。The capacity of a vertical Bell Lab layered space-time （V-BLAST） system with a linear minimum-mean-square error （LMMSE） receiver in a continuous flat fading channel was considered. The effect of the channel estimation error was analyzed to obtain an expression for the output signal-to-interference and noise-ratio of LMMSE receiver. Random matrix theory was then used to get a closed-form solution with the training-based channel estimate. Since the analysis uses large system analyses via the distribution law of random matrices, the results are asymptotic in nature. Simulations show that the solution is still valid for limited-scale systems. The optimization over training length and training interval to maximize the capacity are also given. The optimal results are found numerically due to the complexity of capacity formula as functions of the Doppler frequency and signal-nolse-ratio.

关 键 词：移动通信 空间复用 信道估计 Doppler频谱 渐进容量 训练优化 

分 类 号：TN929.5[电子电信—通信与信息系统]