PRML regenerating apparatus having adjusted slice levels
US6002538A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 1995 |
| Grant date | Dec 14, 1999 |
| Priority date | — |
| Expiry date | Mar 8, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/044
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is a PRML regenerating apparatus for regenerating a signal read by a head from a storage medium. This PRML regenerating apparatus has a waveform equalizing circuit for waveform-equalizing the read signal, a maximum-likelihood decoder for maximum-likelihood-decoding, after obtaining a determination value by comparing the equalized output with upper and lower slice levels, this determination value and a control circuit for setting variable a distance between the upper slice level and the lower slice level of the maximum-likelihood decoder. The distance between the upper and lower slice levels can be thereby set variable in accordance with an equalization characteristic. A ternary determination circuit of the maximum-likelihood decoder is constructed of a memory for storing a correspondence table of the equalized output and the upper or lower slice level versus the determination result and the next upper or lower slice level. The ternary determination circuit can be thereby actualized with a simple configuration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.