Synchronization method and apparatus for a telephone switching system
US4757521A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 1984 |
| Grant date | Jul 12, 1988 |
| Priority date | — |
| Expiry date | May 17, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/0066
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for synchronizing a digital data signal from a first location, such as a digital telephone station, and which is transmitted to a second location, such as the station interface of a telephone switching system common equipment input, with a digital data signal at the second location, is disclosed. The method includes transmitting a data signal to the second location from the first location, receiving the data signal at the second location and determining if the data signal is present at a selected time. Digital coded data is sent to the first location from the second location for selecting successive delay times at the first location. When the delayed data signal is present at the second location at the selected time, the optimum value of the delay time is determined at the second location, preferably by averaging the values of the delay times at which the data signal was first detected and last detected at the second location. Digital coded data corresponding to the optimum delay time is then sent to the first location to select the optimum delay time at the first location.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.