阐述回声消除技术原理,介绍自适应回声消除器基本结构,分析两类消除回声的基本算法,并提出基于两类算法的几种改进型算法,为提高IP电话的话音质量提供一定的参考。-　The element of the echo cancellation and the configuration of the adaptive echo canceller is first in troduced in this paper. It also analyzed two kinds of basical go ri