This point out that in order to improve the LMS algorithm performance, the gradient are optimally estimated, or the error signal are nonlinearity processed,these methods are equipollent.

最速下降法梯度优化估误差信号非线性处理，是改善LMS算法性能等同措施。

A new variable step-size LMS adaptive filtering algorithm is presented, which makes use of the intercorrelation function of the relative output error signal to control the new variable step-size.

针上述问题，提出了一种新长LMS自适应滤波算法，它采用相误差互相关函数来控制长更新。