By modeling the effects of slicer errors, we derive an algorithm for determining hybrid DFE coefficients which account for the increase in interference from error propagation. The coefficients of the hybrid DFE can be determined adaptively through the LMS algorithm by including an SINR dependent "leakage" factor in the feedback filter update equation. The hybrid DFE coefficients reduce to those of a linear equalizer (LE) at low SNR and a DFE at high SNR, while achieving an optimal compromise between these extremes. In the SNR region of greatest interest for systems with high spectral efficiency, simulation results show that the hybrid DFE offers significant gains compared to a regular DFE or an LE of comparable complexity.
['Srikant Jayaraman', 'Ivan Jesus Fernandez-Corbaton', 'John Edward Smee']
Hybrid decision feedback equalization