Mathematical Modelling of Adaptive Acoustic Echo Cancellation Algorithm for Speech Signals
Abstract
In the use of hands-free telephone, loud speaker and microphone placed a significant distance from each other, as in a teleconferencing environment. In such an environment, the microphone picks up not only the speech signal radiated by the loudspeaker,
but also its echo from the borders of the enclosure. The users of the system become annoyed by having to listen to their own speech, delayed by the round-trip time of the system. To overcome the annoying presence of acoustic echo in these telecommunication environments, the common practice is to use an adaptive echo canceller. The basic principle of acoustic echo cancellation is to adaptively synthesize a replica of the echo and subtract it from the echo-corrupted signal. A remote speaker’s signal is radiated by the loudspeaker, picked up by the microphone, and convolved with near speaker’s signal. The adapted far end signal is subtracted from the convolved signal to give an echo free signal by using various adaptive filtering algorithms such as LMS and NLMS; the performance analysis and mathematical modeling
Author
Gopal Thangavel
Gunasekaran Thangavel
N. Veluthambi
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