System and method for synchronization of devices across a packet network
US7103072B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2002 |
| Grant date | Sep 5, 2006 |
| Priority date | — |
| Expiry date | Jan 24, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/0685
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A local time of a broadband loop carrier terminal is synchronized to a network time received from a source external to the broadband loop carrier terminal by comparing the local time to the network time to generate an error offset, and adjusting the local time based on the error offset. The network time may be received in response to a Network Time Protocol (NTP) poll transmitted by the broadband loop carrier terminal. In some cases, the poll is transmitted over a communication medium using an asynchronous packet protocol, such as Ethernet or TCP/IP. In one embodiment, the local time is based on the output of a local oscillator (e.g., a voltage controlled oscillator), the frequency of which may be adjusted using control logic which uses a filtered version of the error offset along with a factory calibration and/or temperature compensation to produce a control voltage to control the oscillator frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.