IEEE transactions ON SIGNAL PROCESSING VOL. 44. NO. 3, MARCH 1996

A Direct solution for Blind Separation of Sources

A. Mansour and C. Jutten

Abstract-This correspondance proposes a direct estimation of the
  mixing matrix in the source separation problem. As a new result, we prove
  that for non-Gaussian sources, the mixing matrix can be obtained by
solving a fourth-degree polynomial equation that derives from nonlinear
equations only involving fourth-order cumulants.