EPR4 DETECTOR IN PR4 EQUALIZATION SAMPLING DATA DETECTION CHANNEL, EPR4 DETECTION METHOD, DIGITAL INFORMATION STORAGE AND RETRIEVAL CHANNEL

摘要

PROBLEM TO BE SOLVED: To provide a post processor with low complexity with respect to an EPR4 channel. ;SOLUTION: An EPR4 detector 36 includes a PR4 Viterbi detector 38 and an EPR4 post processor 40 to improve an output sequence estimated by an output of the PR4 Viterbi detector 38. The PR 4 Viterbi detector 38 generates digital estimate of coded digital information in a channel according to a path through a PR4 trellis and generates other path information relating to other path through the PR4 trellis. An EPR4 post processor 40 has a PR4 path storage circuit, an error event selection circuit and a path correction circuit.;COPYRIGHT: (C)1997,JPO