Title :
Automatic hierarchy control over Stratum 1 redundant time and frequency systems
Author :
Peled, E. ; Zelitzki, M. ; Nemesh, A.
Author_Institution :
TFL Time & Frequency Ltd., Holon, Israel
Abstract :
The authors describe a system for Stratum 1 telecommunications or for any highly redundant frequency source system. Traditionally, primary reference systems are ensembles of three frequency sources in a 2:1 redundant configuration. One of the sources is used, while the other two are hot standby substitutes. The three frequency sources can be any combination of clocks (such as cesium, rubidium, or OCXO), or of the same kind. Whatever the structure is, the quality of the frequency sources can change in time due to aging, atomic tube degradation, etc. An aid for such systems that can find out which of three clocks is the best by various means and change priorities in accordance with this scaling has been developed
Keywords :
automatic telephone systems; clocks; digital communication systems; redundancy; synchronisation; telecommunications control; telephone exchanges; Stratum 1 telecommunications; automatic hierarchy control; clocks; digital exchange; hot standby substitutes; primary reference systems; redundant frequency source system; redundant time system; Aging; Clocks; Coaxial components; Control systems; Counting circuits; Degradation; Frequency; Switches; Telecommunication control; Time measurement;
Conference_Titel :
Frequency Control, 1991., Proceedings of the 45th Annual Symposium on
Conference_Location :
Los Angeles, CA
Print_ISBN :
0-87942-658-6
DOI :
10.1109/FREQ.1991.145959
