说明：  MIMO是移动4G的通信技术，但是受到地形和外部建筑的影响，收到的无线信号含有多径，产生严重的码间干扰，文章中阐述了用MMSE方法对信号进行均衡，很好得恢复MIMO信号
(4G MIMO mobile communication technology, but by the terrain and outside the building, the wireless signal containing the received multipath produce serious inter-symbol interference, the article describes a method of using the MMSE equalization of the signal, the recovery was very good MIMO signal)