A DSP based long distance echo canceller using short length centered adaptive filters

This paper describes an implementation of a long distance echo canceller which copes with double talking situations and exceeds the CCITT G.165 recommendation. The proposed solution is based on short length adaptive filters centered on the positions of the most significant echoes, which are tracked by time-delay estimators. To deal with double talking situations a speech detector is employed. The resulting algorithm enables long-distance echo cancellation with low computational requirements. It reaches greater echo return loss enhancement and shows faster convergence speed as compared with results reported in recent literature.