利用DCT_LMS方法分别对锯齿波、方波、正弦波进行了滤波，滤波效果较好的恢复出了真实信号，相比单纯LMS滤波方法有了极大的提高。(The DCT_LMS method is used to filter the sawtooth wave, Fang Bo and sine wave. The real signal is recovered with better filtering effect, which has been greatly improved compared with