近年来,因特网技术快速发展,其业务类型已进入传统电信的实时话音通信。文中首先论述了VoIP(Voice Over IP)技术中的延迟和回声问题,并回顾了IP电话中基本的回声抵消算法,最后结合IP网络的长延迟特性给出了一种基于延迟估计的回声抵消优化算法。 In recent years, with the rapid development of Internet technology, its business type has entered the real-time voice communication of the traditional telecommunications. Firstly, the problems of delay and echo in VoIP (Voice over IP) are discussed. The basic echo cancellation algorithm in IP phone is reviewed. Finally, an echo canceling optimization based on delay estimation is given based on the long delay of IP network algorithm.