Time and Frequency Activities at the U.S. Naval Observatory

Abstract

The U.S. Naval Observatory (USNO) has provided timing for the Navy since 1830 and, in cooperation with other institutions, has also provided timing for the United States and the international community. Its Master Clock (MC) is the source of UTC (USNO), USNO's realization of Coordinated Universal Time (UTC), which has stayed within 5 ns rms of UTC since 1999 and within 2.7 ns rms in 2007. The data used to generate UTC (USNO) are based upon 70 cesium and 24 hydrogen maser frequency standards in three buildings at two sites. USNO disseminates time via voice, telephone modem, LORAN, Network Time Protocol (NTP), GPS, and Two-Way Satellite Time Transfer (TWSTT). This paper describes some of the changes being made to meet the future needs for precision, accuracy, and robustness.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 2007
Accession Number
ADA485484

Entities

People

  • Demetrios N. Matsakis

Organizations

  • United States Naval Observatory

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Accuracy
  • Artificial Satellites
  • Atomic Beam Masers
  • California
  • Clocks
  • Frequency
  • Frequency Standards
  • Jet Propulsion
  • Masers
  • Measurement
  • Navigation
  • Observatories
  • Precision
  • Standards
  • Time Intervals
  • United States
  • Urban Areas

Readers

  • Positioning, Navigation, and Timing (PNT) Technology.

Technology Areas

  • Space