Several main adaptive filters (1)LMS adaptive filter(闭环结构) (2)RLS (Recursive least-squares) adaptive filter （开环结构） (3)IIR adaptive filter ■■■■■ 77 Several main adaptive filters (1) LMS adaptive filter ( 闭 环 结 构 ） (2) RLS (Recursive least – squares) adaptive filter （ 开 环 结 构 ） (3) IIR adaptive filter 2222