A Subband Decision Feedback Equalizer for ATCS DTV Receivers with Improved Efficiency of Train Sequency

LMS-DFE is preferred as an effective solution to coping with inter-symbol interference (ISI) for ATSC DTV receivers. In the DTV channel, echo delay often covers hundreds of symbols, by performance constrains, which leads to very large-scale equalizer with huge computational complexity. One consequence of the adaptive large-scale equalizer is that of very slow convergence. It is combined with error propagation, the inherent drawback of DFE, seriously deteriorating the performance of the receivers, especially in severe channels. In this paper, we apply the sub band processing to LMS DFE for sufficient speed of convergence, trying to open the eye diagram until the end of train sequence. It is ready for the decision-directed mode. Simulation results show that the proposed scheme improves the performance of the equalizer, especially in severe channels.