LS（Least Square，最小二乘法）算法是信道估计算法中最基本的算法之一。在MIMO-OFDM系统中，经常选择LS算法或其改进算法对信道进行估计。利用LS算法设计信道估计器，算法结构简单易于实现，且估计器不需要知道信道中各个收发天线对之间的自相关矩阵和噪声。-LS (further Square, Least Square) algorithm is one of the most basic algorithm of channel estimation algorithm. In MIMO- OFDM systems, often choose LS algorithm and its improved algorithm for channel estimation. Use of channel estimator and the LS algorithm design algorithm structure simple and easy to implement, and the estimator does not need to know in the channel between the sending and receiving antenna for autocorrelation matrix and noise.