回波抵消器中常用的几种自适应滤波算法有LMS, NLMS, RLS等算法。对现有主要算法的性能进行了分析，并对优缺点进行评价和比较。为了在收敛速度和运算量之间得到很好的折衷，对NLMS算法改进，得到了 PNLMS,Echo cancellation devices commonly used in adaptive filtering algorithm has several LMS, NLMS, RLS, such as algorithms. The main algorithm of the existing performance analysis, and evaluation and comparison of the advantages and disadvantages. For the convergence between computing speed and a good compromise on the NLMS algorithm improvements have been PNLMS