An adaptive spline non-linear function for blind signal processing

A new adaptive non linear function for blind signal processing is presented. It is based on a spline approximation whose control points are adaptively changed using information maximization techniques. The monotonously increasing characteristic is obtained using suitable B-spline functions imposing simple constraints on its control points. In particular, the problem of adaptively maximizing the entropy of the output is considered for flattening (make uniform) the probability density function (pdf) of a random signal. We derive a simple form of the adaptation algorithm and present some experimental results that demonstrate the effectiveness of the proposed method.