Clock recovery system in digital rotary scan magnetic playback devices
US4607296A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 17, 1985 |
| Grant date | Aug 19, 1986 |
| Priority date | — |
| Expiry date | Jul 17, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/1403
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved clock recovery system for use in digital rotary scan magnetic playback devices utilizing a phase locked loop. The clock signal recovered from the playback data has a phase error with a periodic component caused by time base variations in the playback data and a random noise component due to playback channel noise. The phase locked loop of the invention tracks the periodic component, while it suppresses the random noise component. The improved system is suitable for tracking wide bandwidth dynamic time base variations in the playback data without introducing phase errors caused by random noise into the recovered clock signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.