Triply-Redundant Precision Time and Frequency Standard
Abstract
This paper describes a triply-redundant precision time frequency standard. The standard combines three high performance, field-proven Frequency Electronics devices; namely, the cesium beam frequency standard, the rubidium frequency standard and the SC-cut quartz oscillator in a single 5-1/4 inch high rack-mounted instrument. Switching between redundant subsystems is accomplished automatically in a glitch-free manner (i.e., negligible phase perturbation), utilizing a process of dynamic phase-matching in con junction with digital memory circuits. The system design is based upon the incorporation of a Model FE-5600A Rubidium Standard within the Model FE-5440A (military nomenclature O-1824/U) Cesium Frequency Standard, and utilization of disciplining phase lock loop circuitry from the AN/URQ-23A Disciplined Time Frequency Standard. In the primary mode, the system functions as a Cesium Standard with a long-term stability of less than 1 x 10(exp -11). In the secondary (back-up) mode, the rubidium standard provides a thirty day stability of less than 3 x 10(exp -11). The tertiary (backup) mode offers the low drift rate of the SC-cut quartz oscillator, namely less than 1 x 10(exp -11) per day.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1987
- Accession Number
- ADA500457
Entities
People
- D. Silvermetz
- M. Bloch
- M. Meirs