Acoustic echo reduction robust against echo-path change with instant echo-power-level adjustment

This paper proposes a new method of residual echo reduction (ER) to track abrupt increases in the residual echo. The method assumes that the spectral structure of the residual echo is maintained even if the residual echo abruptly increases; then, estimates only of the echo power level can be made in a short observation time. The proposed method instantaneously obtains the echo power level by focusing on all frequency-spectral components, and recalculates the echo component using bothe the obtained power level and the spectral structure estimated with the conventional method. The outstanding performance of the proposed method is demonstrated through objective and subjective experiments. The results revealed that the degradation in speech quality was mitigated even if the echo power level increased during the double-talk periods.