MIMO decision feedback equalization from an H-infinity perspective

Abstract

We approach the multiple input multiple output (MIMO) decision feedback equalization (DFE) problem in digital communications from an H-infinity estimation point of view. Using the standard (and simplifying) assumption, that all previous decisions are correct, we obtain an explicit parameterization of all H-infinity optimal DFEs. In particular, we show that, under the above assumption, minimum mean square error (MMSE) DFEs are H-infinity optimal. The H-infinity approach also suggests a method for dealing with errors in previous decisions.