An algebraic principle for blind source separation is presented in this pap
er. This separation principle identifies a (smaller) set of equations whose
solutions can blindly extract non-Gaussian signals. The concept of "M th-o
rder uncorrelatedness" is introduced and it is proven that for Mth-order un
correlated source signals, signals with nonzero kth-order cumulant (2 < k l
ess than or equal to M) can always be extracted by setting a small set of k
th-order cross-cumulants of output signals to zero. The set of kth-order cr
oss-cumulants specified here is a sub-set of those used by other existing m
ethods. The relationship between the algebraic principle and several existi
ng algorithms is presented. The contributions of this principle are the red
uction of the number of cross-cumulants used and the flexibility it affords
in designing algorithms for blind source separation. (C) 1999 Published by
Elsevier Science B.V. All rights reserved.