Fourth-order criteria for blind sources separation

In the problem of blind separation of sources, we define usually a function ( cost, contrast, . . . ) and the solution is based on the search of the extremum of that function. The choice of cost function is then very important, both to have simple computation and to guarantee unicity and convergence to a good solution. In this paper, in the case of instantaneous mixtures of 2 sources, we study two cost functions based on the fourth order cumulant and we prove theoretically and experimentally that the cross cumulant is a simple and good cost function.