Restoration of data and asymmetry compensation in an optical disk reproducing system
US6483793B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 15, 1999 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Jul 15, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2020/1457
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A data restoring apparatus of an optical disk reproducing system restores data recorded on an optical disk from an RF signal read from the optical disk. The apparatus includes an analog to digital converter (ADC) for digitally converting the RF signal in response to a recovery clock signal and generating the digitally converted signal as a digital RF signal, a viterbi decoder for decoding the digital RF signal with a viterbi decoding method and generating a decoded bit stream as restored data, an adaptive phase error compensator for obtaining the phase error between the RF signal and the recovery clock signal and generating a control voltage corresponding to the phase error, and a voltage controlled oscillator for generating the phase-compensated recovery clock signal by varying the frequency of the recovery clock signal corresponding to the control voltage, wherein the adaptive phase error compensator adds a predetermined number of successive digital RF signals generated around a reference voltage and obtains the addition result as the phase error. It is thereby possible to restore correct data since, when the digital RF signal obtained by digitally converting the RF signal passes…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.