公开(公告)号：KR100392365B1

公开(公告)日：2003-07-23

申请号：KR1020010047654

申请日：2001-08-08

Applicant: 한국전자통신연구원

Inventor： 최민석 ,  변경진 ,  김경수 ,  배건성

IPC: H04B7/015

Abstract: PURPOSE: An apparatus for canceling the detection delay of an end point of a double-talk interval and a method therefor are provided to efficiently cancel an echo although an impulse response of an echo path is changed in a point in which a double-talk is ended by detecting the double-talk interval, periodically estimating a power of a signal, and reducing the detection delay of the end point of the double-talk interval. CONSTITUTION: An echo signal estimating unit(21) estimates an echo signal from a reference input signal and a previous residual error signal through an adaptive filtering. A residual error signal generating unit(22) subtracts the estimated echo signal from an expected signal and generates a residual error signal. A power and correlation degree estimation calculating unit(23) estimates and calculates a power of the expected signal, a power of the residual error signal, and a correlation degree between the expected signal and the residual error signal using a forgetting index from the residual error signal and the expected signal generated in the residual error signal generating unit(22). A cross correlation coefficient calculating unit(24) calculates a cross correlation coefficient between the expected signal and the residual error signal using the power of the expected signal, the power of the residual error signal, and the correlation degree calculated in the power and correlation degree estimation calculating unit(23). A cross correlation coefficient comparing unit(25) compares the cross correlation coefficient calculated in the cross correlation coefficient calculating unit(24) with a predetermined threshold value and outputs confirmation information about a double talk interval. An adaptive filter coefficient updating unit(26) updates a coefficient by the adaptive filtering on the basis of confirmation information of a single-talk interval output from the cross correlation coefficient comparing unit(25). A power estimating unit(27) estimates a power on the basis of the double-talk interval output from the cross correlation coefficient comparing unit(25).

Abstract translation: 目的：提供了一种用于消除双方讲话间隔的结束点的检测延迟的装置及其方法，以有效地消除回波，尽管回声路径的脉冲响应在双方对话为 通过检测双方讲话间隔来结束，周期性地估计信号的功率，并且减少双方讲话间隔的结束点的检测延迟。 组成：回波信号估计单元（21）通过自适应滤波来估计来自参考输入信号和先前残余误差信号的回波信号。 残留误差信号生成单元（22）从预期信号中减去估计回声信号并生成残余误差信号。 功率和相关度估计计算单元（23）使用来自残差的遗忘指数来估计和计算期望信号的功率，残差信号的功率以及期望信号和残差信号之间的相关度 信号和在残留误差信号生成单元（22）中生成的预期信号。 互相关系数计算单元（24）使用期望信号的功率，残差信号的功率以及在功率和相关度中计算的相关度来计算期望信号和残差信号之间的互相关系数 估计计算单元（23）。 互相关系数比较单元（25）将在互相关系数计算单元（24）中计算的互相关系数与预定阈值进行比较，并输出关于双通话间隔的确认信息。 自适应滤波器系数更新单元（26）基于从互相关系数比较单元（25）输出的单方讲话区间的确认信息，通过自适应滤波来更新系数。 功率估计单元（27）基于从互相关系数比较单元（25）输出的双端讲话间隔来估计功率。