MIMO MMSE-DFE: a general framework

We investigate and revisit the structure and performance of a multiple input/multiple output (MIMO) decision feedback equalizer (DFE) for a minimum mean square error (MMSE) criterion. The output model dealt with is very general, and applies to filter bank-based multicarrier transmission, CDMA, TDMA, FDMA systems, systems with transmitter-induced cyclostationarity and so on. Moreover, the transmission model and the associated receiver account for excess bandwidth and multi-sensor configurations. The purpose of the paper is to derive MIMO MMSE DFE in a concise manner by means of fractionally spaced devices. From the receiver derived here it clearly appears that the first operation to be performed is matched filtering. Besides, it is also demonstrated why geometrical MSE is the criterion to be used. As an illustrative example, an OFDM transmission scheme is considered