本文提出了一种与线性预测编解码器相结合的新声学回声消除器,由去相关可变步长的NLMS自适应算法和基于回声路径失配方差的双端通话检测算法所组成.Matlab仿真结果表明,与Gordy所提出的回声消除算法相比,本文提出的算法在双端通话和回声路径改变时判别更准确,收敛速度更快;在收敛状态时,ERLE值平均提高了15dB,失调误差平均降低了10dB,具备更好的回声消除性能.
This paper presents a new acoustic echo canceller combined with the linear predictive speech coders, which includes an adaptive FIR (Finite Impulse Response) filter employing the variable step-size de-correlation NLMS (Normalized Least Mean Square) algorithm and a double-talk detector based on the variance of echo-path mismatch. The simulation results conducted by Matlab demonstrate that the proposed algorithms have better echo cancellation performances compared with the echo cancellation algorithms proposed by Gordy. It detects more correctly in both double-talk and echo-path change, converges faster and achieves an average 15dB higher ERLE and 10dB lower misalignment during convergence.