An improved detector for channels with nonlinear intersymbol interference
N.P. Sands, J.M. Cioffi · 2002
The magnetic storage channel exhibits nonlinear intersymbol interference (ISI) at high recording density, which can seriously degrade performance compared to a similar channel with purely linear distortion. The decision feedback equalizer with RAM feedback (RAM-DFE) has been suggested as a receiver for these nonlinear channels, however its performance is limited to canceling the strictly post-cursor nonlinear ISI. We suggest an enhancement to RAM-DFE which can further reduce the effects of nonlinear ISI. Past decisions are combined with channel output samples in the forward filter of a modified DFE to form a nonlinear estimator for the current symbol.>