Control of an adaptive echo canceller using a near-end speech detector

Abstract

In the context of hands-free mobile telephony, acoustic echo cancellation (AEC) remains an important problem to deal with. This work addresses the study of an acoustic echo canceller controlled by a near-end speech detector. As a matter of fact, the echo canceller is an adaptive filter whose coefficients are disturbed by the presence of speech coming from the near-end speaker. Consequently, it is useful to stop the adaptation when this signal is detected to get a better estimation of the echo (far-end speaker). In this paper, a near-end speech detector based on the partial coherence – computed from the observations received by two microphones conditioned on the signal emitted by the loudspeaker – is investigated. To improve the performance of the AEC system, two approaches performing a saving of the AEC coefficients are proposed. The system is assessed through the power of the residual echo.