Robust Acoustic ECHO Control using a Simple ECHO Path Model

In handsfree tele or video conferencing acoustic echoes arise due to the coupling between the loudspeaker and microphone. Usually an acoustic echo canceler (AEC) is used for eliminating the undesired echoes. The weaknesses of AEC are that it is relatively complex and that it is not robust against non-linearities occurring when using low-end components such as small loudspeakers. We are describing an algorithm which models the acoustic echo path by means of an overall delay and a coloration effect filter. The echo is removed by means of short-time spectral modification. The algorithm design aims at low computational complexity and high robustness. The effect of echo path changes and non-linearities on the performance of this algorithm are investigated