ECHO CANCELLATION METHOD AND ECHO CANCELLER IMPLEMENTING SUCH A PROCESS

摘要

A reception signal (x(n)) is input to an echogenerator system (1). An observation signal (z(n)) isgathered from the system. The reception signal isfiltered to produce an echo prediction signal (y(n)). Theecho prediction signal is subtracted from the observationsignal to produce an error signal (e(n)). The observationsignal (z(n)) is decomposed into M spectral componentsrelating to different frequencies of the spectrum. Mcorresponding spectral components of the echo predictionsignal (y(n)) are obtained. M quantities, each having avalue with progressive variation representative of adegree of similitude between, respectively, one of the Mspectral components of the observation signal and thecorresponding spectral component of the echo predictionsignal, are calculated. At least one spectral shaping ofthe error signal (e(n)) is carried out as a function ofthese M calculated quantities so as to adapt thefiltering and/or to deliver the output signal from theecho canceller.