An adaptive decision feedback equalizer using error feedback

The decision feedback equalizer (DFE) can compensate for channels with severe intersymbol interference (ISI) without as much noise enhancement as the linear equalizer (LE). We propose a new DFE which can increase the performance of the DFE further by using error feedback. The performance increase is achieved by reducing the error signal correlation (using an error feedback filter), which cannot be reduced by the feedforward or feedback filter. The hardware complexity for the proposed approach is minimal since it requires only the addition of a few taps to the conventional DFE. Based on theoretical analysis and computer simulations, the proposed approach is shown to be much more effective than the conventional DFE, especially for channels with large ISI and small AWGN.