Enhanced holdover for synchronous networks employing packet switched network backhaul
US7606541B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 12, 2006 |
| Grant date | Oct 20, 2009 |
| Priority date | — |
| Expiry date | Sep 10, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/0667
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Systems and methods are disclosed to maintain synchronous communications that uses a global positioning system satellite, a primary communication unit, and a secondary communication unit. The satellite based time reference broadcasts a reference signal to the primary communication unit and the secondary communication unit. The primary communication unit contains a high quality oscillator, and operates a virtual model of a secondary oscillator which is located in the secondary communication unit. The primary and secondary units have synchronous communications with each other by using a global positioning system satellite broadcast as a reference signal. If the secondary unit loses its signal from the global positioning system, the secondary oscillator enters a holdover state and transmits a notification of the holdover state to the primary communications unit. The primary communication unit then transmits time insensitive synchronization data based upon the virtual model through the packet switched network to the secondary communications unit to maintain synchronization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.