SIGNAL PROCESSING DEVICE, SIGNAL PROCESSING METHOD, INFORMATION STORAGE DEVICE, AND INFORMATION REPRODUCING DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce bit-shift without increasing a recording frequency by Nyquist-equalizing a bit string obtained from a processed result in which processing of (1-D) (D is delayed by 1 bit) is performed for an input bit. SOLUTION: A NRZI recording system 101 performs operation of 1/(1-D)}×(1-D), and outputs a signal of step type. A magnetic reproducing system 103 filters a signal impulsed by a differential detecting section 102 and samples it. An equalizer 14 constitutes a Nyquist equalizer with the magnetic reproducing system 103, and product with a transfer characteristic of the magnetic reproducing system 103 is made a cosine roll-off characteristic. Thereby, a partial response equalization wave-form having any amplitude out of +1, 0, -1 in the prescribed time is outputted to an output of the equalizer 104. A level detecting section 105 detects a signal from the equalizer 104 with a ternary level, and a maximum likelihood detecting section 106 detects maximum likelihood detected result and decodes an output code.