中文说明：
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。
English Description：
LS (least square) algorithm is one of the most basic channel estimation algorithms. In MIMO-OFDM system, LS algorithm or its improved algorithm is often used to estimate the channel. Using LS algorithm to design channel estimator, the structure of the algorithm is simple and easy to implement, and the estimator does not need to know the autocorrelation matrix and noise between each antenna pair in the channel.