Recursive methods for ARMA parameter estimation is attractive for speech spectrum analysis . ǰhese methods can
not be applied directly to speech analysis where the input signal (the excitation source of the vocal tract) is unknown .
In this paper, after clarifying the mechanism, in the case of unknown input signal, that limits the estimation
precision, we describe a solution based on the impuls detection and suppression in the residue . ǰhis approach can
improve the parameter estimation accuracy mainly for the case where the residue is close to an impuls train . It has
been shown that this method improves the spectrum estimation of speech signais .On veut montrer que lorsqu'on ne connaît pas le signal d'excitation, la précision de l'estimation des paramètres est très limité
