Soft signal-space detection for the Lorentzian magnetic recording channel

The feasibility of soft signal-space detection (SSD) is demonstrated for the Lorentzian magnetic recording channel. The exact form of soft SSD detectors operating in intersymbol interference channels is presented. The SSD detectors can be realized with lower complexity in the log-domain, but without appreciable performance degradation, by parametric modeling. The parametric SSD detectors model the soft a posteriori probability information as the output of a parametric function whose inputs are the distances between the observation vector and the hyperplanes which separate signal constellations of opposite class.