Characteristics of acoustic echo cancellers using sub-band sampling and decorrelation methods

Abstract

An acoustic sub-band echo canceller offering high speech quality has been implemented. Echo cancellation in excess of 40 dB was obtained over the 7 kHz frequency band in the hardware with 4000-tap FIR filters. It was confirmed using a decorrelation algorithm that the convergence speed for coloured signals was about three times faster than the conventional NLMS algorithm.