Unbiased decision feedback equalization
Constantinos B. Papadias, Arogyaswami J. Paulraj · 2002
We consider the problem of decision feedback equalization (DFE) with the use of finite impulse response (FIR) filters. We show that, contrarily to what seems to be believed, unbiased finite-length DFE solutions exist for any FIR channel, provided that the feed-forward (FFF) and feedback (FBF) filter lengths are properly chosen. This allows for the derivation of the expressions for the optimal zero-forcing (ZF) and minimum-mean-square-error (MMSE) finite-length solutions. The result can be also used as a guideline for choosing the lengths of the FFF and FBF DFE filters.