Analysis and control of the stability of a differential separation method for underdetermined convolutive mixtures

Our contributions in this paper are twofold. We first analyze the stability of a differential blind source separation method for underdetermined convolutive mixtures that we proposed elsewhere. This shows that the adaptation gains of this method should be selected depending on the signs of the differential powers of the sources in order to control its stability. As these signs are unknown in a blind context, we then develop a method for deriving them from the observed mixed signals.