Clock recovery apparatus
US6747826B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 2003 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Jan 28, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/0083
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A reproduction signal 10 is processed in an AD converter 4 and an equalizer 16 to be a decoder input signal 12. The decoder input signal 12 is used to calculate a phase error signal 25 and a quality judgement signal 26. A phase-frequency error detection circuit 22 retains a sign of the phase error signal 25 obtained when the quality judgement signal 26 is changed in quality from “good” to “bad”. The phase-frequency error detection circuit 22 then outputs, as a phase-frequency error signal 27, the phase error signal 25 when the signal quality is “good”, and a given value corresponding to the retained sign when the signal quality is “bad”. A voltage controlled oscillator 9 generates a recovered clock signal 11 whose frequency is based on the oscillation control signal 15 generated by the phase-frequency error signal 27.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.