Method of maximum likelihood decoding and digital information playback apparatus
US5719843A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 21, 1996 |
| Grant date | Feb 17, 1998 |
| Priority date | — |
| Expiry date | Jun 21, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M13/6343
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A digital information playback apparatus comprises A/D converter that converts a playback signal into digital data, a maximum likelihood decoder that decodes the quantized data output from the A/D converter to obtain the original digital information, and a timing signal extractor that generates a sampling clock used in the A/D converter, and wherein the maximum likelihood decoder detects the response characteristic of the record/playback system and obtains level fluctuations contained in the playback signal, based on the survival path obtained as a maximum likelihood decoding result, to control the expected multilevel equalized values used in the maximum likelihood decoder, the timing signal extractor obtains level fluctuations, based on the survival path obtained as a maximum likelihood decoding result, and obtains the component of the level fluctuations due to phase shifts of the sampling clock of the VCO to control the phase of the sampling clock of the VCO.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.