Complex-Valued Maximum Joint Entropy Algorithm for Blind Decision Feedback Equalizer

This paper proposes the complex domain solution of the blind decision feedback equalizer (DFE) based on joint entropy maximization (JEM) criterion. For the feedback filter of DFE, a new complex activation function is defined and then the stochastic gradient algorithm of the JEM type is derived. The fact that the JEM cost is a real function of complex quantities suggests the method associated to a least man-square criterion.