Simplified EPR4 detection

A new detector implementation for the extended class 4 partial response channel is presented. This implementation uses two, interleaved ternary 1-D detectors followed by a post-processor to detect the recorded data. The post-processor consists of a sequence check followed by a determination of the N most-likely paths through the two 1-D detectors, if necessary. This system is shown via simulation to perform as well as the standard EPRI maximum likelihood detector.