Convolutive blind source separation of speech signals based on amplitude modulation decorrelation

Abstract

The problem of blind separation of a convolutive mixture of speech signals is considered. Signal separation is performed in the frequency domain. The amplitude modulation decorrelation algorithm for convolutive blind source separation of speech is described, the first ideas of which were presented by Anemüller at the joint ASA/EAA/DAGA meeting, Berlin, 1999. The algorithm is based on the fact that the frequency-specific envelopes of speech signals exhibit correlation across different frequencies. This feature can be used to solve the ‘‘permutation problem’’ of frequency-domain-based blind source separation algorithms. Furthermore, it leads to separation of good quality since it results in a high number of constraints which must be fulfilled by the unmixed signals. Results for the separation of speech signals are presented for different mixing scenarios, including real-room reverberant mixing.