Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Research Article Combining Superdirective Beamforming and Frequency-Domain Blind Source Separation for Highly Reverberant Signals | Hindawi Publishing Corporation EURASIP Journal on Audio Speech and Music Processing Volume 2010 Article ID 797962 13 pages doi 2010 797962 Research Article Combining Superdirective Beamforming and Frequency-Domain Blind Source Separation for Highly Reverberant Signals Lin Wang 1 2 Heping Ding 2 and Fuliang Yin1 1 School of Electronic and Information Engineering Dalian University of Technology Dalian 116023 China 2 Institute for Microstructural Sciences National Research Council Canada Ottawa Canada K1A0R6 Correspondence should be addressed to Lin Wang wanglin_2k@ Received 14 January 2010 Accepted 1 June 2010 Academic Editor Harvey Thornburg Copyright 2010 Lin Wang et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Frequency-domain blind source separation BSS performs poorly in high reverberation because the independence assumption collapses at each frequency bins when the number of bins increases. To improve the separation result this paper proposes a method which combines two techniques by using beamforming as a preprocessor of blind source separation. With the sound source locations supposed to be known the mixed signals are dereverberated and enhanced by beamforming then the beamformed signals are further separated by blind source separation. To implement the proposed method a superdirective fixed beamformer is designed for beamforming and an interfrequency dependence-based permutation alignment scheme is presented for frequencydomain blind source separation. With beamforming shortening mixing filters and reducing noise before blind source separation the combined method works better in reverberation. The performance of the proposed method is investigated by separating up to 4 sources in different environments with reverberation time from 100 ms to 700 ms. Simulation results verify .
