Method and system for calibrating an oscillator circuit using a network based time reference
US6639957B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2002 |
| Grant date | Oct 28, 2003 |
| Priority date | — |
| Expiry date | May 13, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0083
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and system of compensating for reference frequency drift utilizes time stamps from a networked reference clock to adjust a local crystal oscillator of a communications device. In an example embodiment, a microprocessor arrangement of the communications device obtains a synchronization time stamp from a networked clock arrangement and synchronizes the local oscillator clock and a clock circuit of the microprocessor with the time stamp. After a predetermined time duration has transpired, a calibration time stamp is obtained from the network clock and the difference between the calibration time stamp and the current time of the clock circuit is extracted. The clock circuit and the networked clock arrangement are then synchronized and the local crystal oscillator is adjusted for crystal aging as a function of the difference between the calibration time stamp and the current time of the clock circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.