一种无双端会话检测的回声抵消算法

Echo canceling algorithm without double-talk detection

为了解决回声抵消器中双端会话检测器计算量大,以及由于其时间的延迟而导致回声抵消性能恶化的问题,提出了一种无双端会话检测的信号的时变功率谱声回声抵消算法。根据双端会话时近端会话与远端会话相互之间的独立性,推导出远端会话信号的时变功率通过回声路径的冲激响应系统与麦克风输入信号的时变互功率相等,利用最小均方误差的自适应滤波来估计回声路径的冲激响应,从而将回声抵消掉。该算法不同于现有的回声抵消算法,它在进行回声抵消的过程中,不需要进行双端会话检测。通过将该算法的步长进行归一化处理,使得自适应滤波器的系数收敛变快,稳定性变强。仿真实验表明,该算法能够在各种会话情况下进行有效的回声抵消。

In order to reduce the high computational complexity load of the double-talk detector in the echo canceller and solve the time-delay problem which leads to the deterioration of the echo canceling performance,a without double-talk detectors based on signal time-varying power spectrum for acoustic echo canceling has been proposed.With the assumption,the near end and the far end speech are independent each other,the far end signal power passing the impulse response of the loudspeaker-enclosure-microphone-system equals the input microphone speech signal power,then using the Least Mean Square error principle for the adaptive filter to cancel the acoustic echo.This method is different from the traditional methods which need to detect the double-talk cases in solving the echo problem during the double-talk periods.Through making the step size normalization,the convergence time of the filter coefficients is reduced.At the same time,the filter becomes more robust.Simulation results show that the proposed algorithm can effectively work in all talking conditions.