Patent · US Expired

Method and apparatus for precision time distribution in telecommunication networks

US4926446A · kind A · utility

23Cited by
2References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 25, 1988
Grant dateMay 15, 1990
Priority date
Expiry dateNov 25, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04J3/065
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A series of nodes in a telecommunications network are connected by a bi-directional transmission path. An outgoing signal passes each of the intermediate nodes in the path and sets a counter timing at each intermediate node. The outgoing signal then returns from the loop node with time information attached to it. As the returning trigger signal passes the intermediate nodes, the intermediate nodes stop counting the elapsed time since the trigger signal passed the intermediate node, and latches the time information. Precision time synchronization information is then determined for each intermediate node by halfing the two way travel time from the intermediate node to the loop node, adjusting for propagation and processing delays, and adding it to the time information from the loop node.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.