(EN)
An echo cancelling system for communication systems. The system includes an adaptive filter (34) that processes the speech signal re-constructed by a speech decoder (30) to generate an echo estimate. The echo estimate is subtracted from the echo containing signal propagating in the communication link to remove or at least reduce the echo corruption. The tap coefficients of the adaptive filter are established on the basis of an error signal that is representative of difference between the echo estimate and the actual echo and on the basis of a signal element that is a component of the re-constructed speech signal. The signal element is highly decorrelated using a decorrelation filter (38) to enable the adaptive filter to converge faster and manifest an improved echo return loss enhancement.
(ZH) 一种用于通讯系统的回声消除系统。该系统包括一个自适应滤波器(34),该滤波器处理由语音解码器(30)重构的语音信号来产生回声估计值。该回声估计值被从在通讯链路中传播的包括回声的信号中减去来除去或至少减少回声噪声。自适应滤波器的抽头系数在误差信号和重构语音信号分量信号的基础上确立,其中的误差信号表示回声估计值与实际回声之间的差值。通过使用解相关滤波器(38),该信号分量被高度解相关使得自适应滤波器更快收敛并表现出提高的回声返回损耗改善。