Decision Feedback Equalization from Anh Perspective

We approach the nonlinear decision feedback equalization problem from an H estimation point of view. Using the standard (and simplifying) assumption that all previous decisions are correct, we obtain an explicit parameterization of all H optimal decision feedback equalizers. In particular, under the above assumption, we show that MMSE decision feedback equalizers are H optimal. The H approach also suggests a method for dealing with errors in previous decisions, and results in an equalization scheme with improved performance over other equalizers that do not take such errors into account.