说明：  由于通常的通信信道的冲激响应的稀疏性，使得NLMS算法的收敛速度还有待提高。所以，近年来，有学者提出了成比例的归一化的均方误差算法(PNLMS)。PNLMS在自适应过程的开始阶段有着很快的收敛的速度，但是迭代过程越往后，收敛速度越慢。于是，众多学者提出了许多的改进算法。本程序是通过matlab仿真对近年来流行的PNLMS,IPNLMS,MPNLMS等算法进行的仿真程序
(As usual communication channel impulse response sparse, making the convergence rate of NLMS algorithm to be improved. Therefore, in recent years, some scholars have proposed a proportional to the normalized mean square error algorithm (PNLMS). PNLMS the beginning of the adaptive process has a fast convergence speed, but the more backward iterative process, convergence slower. Thus, many scholars have made many improvements in algorithms. Matlab simulation of this program is popular in recent years PNLMS, IPNLMS, MPNLMS other algorithms of the simulation program)