12:30pm
EQuad E415
Title:
Blind Separation of Disjoint Orthogonal Signals: Demixing N Sources From
2 Mixtures
(joint work with Alexander Jourjine and Scott Rickard)
Abstract:
We present a novel method for blind separation of any number of
sources using only two mixtures. The method applies when sources are (W-)
disjoint orthogonal, that is, when the supports of the (windowed) Fourier
transform of any two signals in the mixture are disjoint sets.
We show that, for anechoic mixtures of attenuated and delayed sources,
the method allows one to estimate the mixing parameters by clustering
ratios of time-frequency representations of the mixtures. The estimates
of the mixing parameters are then used to partition the support of the
(windowed) Fourier transform of one mixture to recover the original
sources. The technique is valid even in the case when the number of
sources is larger than the number of mixtures. The general results are
verified on both speech and wireless signals. Sample sound files can be
found at:
http://www.princeton.edu/~srickard/bss.html