Blind adaptive decision feedback equalization: A class of channels resulting in ill-convergence from a zero initialization

This paper addresses the ill-convergence of blind adaptive decision feedback equalizers using the decision-directed algorithm under a zero initialization. In particular, the paper identifies analytically a class of channels for which the adaptive equalizer parameters converge to an undesired minimum where incorrect decision estimates can be made under zero noise. This misbehaviour occurs despite the existence of a DFE parameter setting that perfectly equalizes the channel.