空时分组码系统的盲信道估计

空时编码是实现宽带无线数据通信的一种极有潜力的技术,随着发射天线个数的增加,对空时编码进行信道估计时,所需训练符号的个数也将增加,减少了传输数据的有效时间.本文将子空间方法同空时分组码的特性有机地结合,提出了无需训练序列,直接进行信道估计的方法.它充分利用空时分组码的特性,使得接收信号中,表示信道衰落影响的矩阵各向量间存在一定联系,利用这些联系,结合子空间方法,从接收信号中解得信道信息.Monte-Carlo仿真表明,在信噪比较低时,本文算法带来的信道估计误差对于解码性能影响较小.

Blind Channel Estimation in Space-Time Block Code

Space-time codes exploit the presence of multiple transmit and receive antennas to improve communication performance on multipath radio channels. Increasing the number of antennas increases the required training interval for channel estimation and reduces the available time in which data may be transmitted. In this paper, by combining the subspace method with the special structure of space-time block code, we propose a blind channel estimation algorithm, which does not require any training symbol. With the special structure of space-time block code,in the received signal, the vectors of channel fading matrix have some relation with each other. Combining this relation with subspace method, we can accomplish the blind channel estimation. Monte Carlo simulations show that when the SNR is low,the loss in decoding performance incurred by the error of channel estimate is relatively small.