JOURNAL OF COMPUTERS (JCP)
ISSN : 1796-203X
Volume : 2    Issue : 7    Date : September 2007

A Least-Squares Approach to Blind Source Separation in Multispeaker Environments
Robert M. Nickel and Ananth N. Iyer
Page(s): 59-67
Full Text:
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Abstract
We are proposing a new approach to the solution of the cocktail party problem (CPP). The goal of
the CPP is to isolate the speech signals of individuals who are concurrently talking while being
recorded with a properly positioned microphone array. The new approach provides a powerful yet
simple alternative to commonly used methods for the separation of speakers. It relies on the
existence of so called exclusive activity periods (EAPs) in the source signals. EAPs are time
intervals during which only one source is active and all other sources are inactive (i.e. zero). The
existence of EAPs is not guaranteed for arbitrary signal classes. EAPs occur very frequently,
however, in recordings of conversational speech. The methods proposed in this paper show how
EAPs can be detected and how they can be exploited to improve the performance of blind source
separation systems in speech processing applications. We consider both, the instantaneous
mixture and the convolutive mixture case. A comparison of the proposed method with other popular
source separation methods is drawn. The results show an improved performance of the proposed
method over earlier approaches.

Index Terms
blind source separation, least-squares optimization, cocktail party problem, exclusive activity
periods.