Patent ID: 6269161
Filing Date: 2001-07-31
Classification: H04M

Abstract:
A method of detecting a near-end signal component within an echo-filtered outgoing signal in an acoustic echo canceller system comprising steps of:receiving an incoming signal from a far-end source;transmitting an initial outgoing signal from a near-end source;adaptively filtering an echo of said incoming signal within said initial outgoing signal to produce said echo-filtered outgoing signal; andestimating an amount of said near-end signal component within said outgoing echo-filtered signal that originated from said near-end source by performing Fourier Transform of said echo-filtered outgoing signal and said incoming signal for a defined frequency spectrum, said step of estimating including:(1) examining an energy distribution of said echo-filtered outgoing signal using a threshold energy distribution that is based on said incoming signal for said defined frequency spectrum;(2) computing threshold energy values of said threshold energy distribution for said defined frequency spectrum;(3) computing energy values of said energy distribution of said echo-filtered outgoing signal for said defined frequency spectrum;(4) estimating an energy of a noise floor for said defined frequency spectrum; and(5) selecting near-end energy estimate values for frequency components of said defined frequency spectrum, each of said near-end energy estimate values being the largest frequency-corresponding value of (a) said noise floor, and (b) said energy distribution of said echo-filtered outgoing signal minus said threshold energy distribution.