Estimating UTC - UTC (APL) at the JHU Applied Physics Laboratory

reportActive / Technical Report | Accession Number: ADA503339 | Open PDF

Abstract:

Our master clock accuracy goal at the Time and Frequency Laboratory of the Johns Hopkins University Applied Physics Laboratory JHUAPL is to maintain UTC APL within plus-or-minus 20 nanoseconds of UTC. This is a challenging goal, because it requires the estimation of the future character of UTC - UTC APL up to 6 weeks beyond the latest issue of Circular T from the BIPM. Furthermore, the accuracy of our timescale-based estimation is challenged by the environmental influence on our ensemble of six clocks and the statistical limits to the dynamic characterization of these sources. This paper will describe the estimation algorithm used to determine the steering of UTC APL. We will describe how the residual drift within the JHUAPL timescale affects our ability to estimate UTC - UTC APL and how we have modified the algorithm to remove this drift from the timescale prior to computing the estimation.

Author(s):
Miranian, Mihran ; Weaver, Gregory L. ; Reinhart, Matthew J.
Author Organization(s):
JOHNS HOPKINS UNIV LAUREL MD APPLIED PHYSICS LAB
Descriptive Note:
Conference paper
Supplementary Note:
See also ADM002186. Presented at the Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting (40th) held in Reston, Virginia on 1-4 December 2008. Published in the Proceedings of the Annual Precise Time and Time Interval (PTTI) Systems and Applications Meeting (40th), p219-226, 2008. The original document contains color images.
Pagination:
0009

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release
Distribution Statement:
Approved For Public Release; Distribution Is Unlimited.

RECORD

Collection: TR
Identifying Numbers
Monitor Series:
XD
 Subject Terms
Joint Capability Areas:
JCA_8_Building Partnerships
Modernization Areas:
Quantum Science and Computing
Communities of Interest:
Materials and Manufacturing Processes
Descriptor(s):
*ATOMIC CLOCKS, *ALGORITHMS, *ESTIMATES, *TIME STANDARDS, ACCURACY, DRIFT, LIMITATIONS, LABORATORIES, TIME STUDIES, FREQUENCY STANDARDS, STATISTICS, SYMPOSIA, REPRINTS, NANOSECOND TIME, FREQUENCY
Field(s)/Group(s):
Computer Programming and Software, Test Facilities, Equipment and Methods
Keyword(s):
*UTC(UNIVERSAL TIME COORDINATED), BIPM(BUREAU INTERNATIONAL DES POIDS ET MESURES), CIRCULAR T, ESTIMATION ALGORITHMS
Report Date:
2008 Dec 01
Creation Date:
2009 Aug 26