DSP implementation and performance evaluation of a compact stereo echo canceller

This paper presents a stereo echo canceller implemented by digital signal processors (DSPs) and its performance evaluation. The implemented echo canceller, which takes the cross-correlation between stereo signals into account, has a single adaptive filter per channel. This structure reduces the number of adaptive filters by half compared with the conventional stereo echo canceller which requires two adaptive filters per channel. Analytical results with real impulse responses clarify the conditions in which this echo canceller achieves better performance with a smaller number of taps than the conventional one. Applicable arrangements of microphones and a talker at the far-end are shown. Evaluation by the implemented hardware supports the analytical results. Satisfactory performance is obtained for both white-noise and real-speech inputs