Robust and fast converging decision feedback equalizer based on a new adaptive semi-blind channel estimation algorithm

Abstract

An adaptive equalization scheme based on channel estimation is proposed. The structure of the whole scheme is novel as well as some of its most important constituent parts. The equalization part comprises an adaptive decision feedback equalizer (DFE) whose performance is significantly improved due to the information provided by the channel estimation part. To estimate the channel impulse response (CIR) a new adaptive semi-blind scheme based on the sub-channel response matching (SRM) criterion and implemented in the frequency domain has been developed. The equalization part exhibits a much faster convergence rate as compared to the conventional DFE, hence a much shorter training sequence is required. Moreover a significant reduction of the error propagation phenomenon can be achieved. The above advantages are offered with only a slight increase in computational load compared to classical LMS-based DFE.