Blind signal separation using overcomplete subband representation

Document type: Journal Articles
Article type: Original article
Peer reviewed: Yes
Author(s): Nedelko Grbic, Xiao-Jiao Tao, Sven Nordholm, Ingvar Claesson
Title: Blind signal separation using overcomplete subband representation
Journal: IEEE Transactions on Speech and Audio Processing
Year: 2001
Volume: 9
Issue: 5
Pagination: 524-533
ISSN: 1063-6676
Publisher: IEEE
ISI number: 000169421000006
Organization: Blekinge Institute of Technology
Department: Dept. of Mechanical Engineering (Institutionen för maskinteknik)
Dept. of Mechanical Engineering S-371 79 Karlskrona
+46 455 38 50 00
Authors e-mail:,,,
Language: English
Abstract: This paper discusses a multirate filterbank-based extended infomax algorithm for real-world signal separation, i.e., convolved mixtures separation. Since convolution in the time domain corresponds to instantaneous mixing in the frequency domain, polyphase subband projection naturally becomes an efficient alternative to the Fourier transform based frequency domain approach. The online implementation proposed is featured by a simultaneous inverse channel identification in the frequency domain and signal filtering in the time domain. It is shown that an over-representation structure reduces aliasing between different bands and results in more accurate inverse channel estimates. Therefore, it provides better performance than the Fourier transform based structure in the measures of both separation and distortion. The performance limitation of the method is also evaluated in terms of the Wiener solution.
Subject: Signal Processing\Speech Enhancement
Signal Processing\Beamforming
Keywords: Blind system identification, microphone array