A Summary of the GPS Constellation Clock Performance

Abstract

The Naval Research Laboratory (NRL) conducts comprehensive analyses of the Global Positioning System (GPS) atomic frequency standards under the sponsorship of the 2nd Space Operations Squadron (2SOPS) at the Master Control Station (MCS) in Colorado Springs, Colorado. The analysis is based on clock estimates that NRL computes from GPS monitor station carrier-derived pseudo-range measurements and National Geospatial-Intelligence Agency (NGA) computed precise post-fit orbit ephemerides. The purpose of the analyses is to determine the performance of the timing signals originating from the atomic frequency standards onboard the space vehicles. Metrics used in the analyses include frequency, drift, stability profiles, and stability histories based on the Allan and Hadamard variances. The relative performance of the space vehicle clocks is ranked and presented according to the clock types flown in GPS. An overview of the GPS constellation with respect to the lifetimes of space vehicles and space vehicle clocks, both active and deactivated, is also presented.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 2007
Accession Number
ADA485348

Entities

People

  • James A. Buisson
  • Jay Oaks
  • Marie M. Largay

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Air Force
  • Artificial Satellites
  • Clocks
  • Constellations
  • Frequency Standards
  • Global Positioning Systems
  • Measurement
  • Satellite Constellations
  • Spacecraft
  • Specifications
  • Standards
  • Time Intervals
  • Vehicles

Readers

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

Technology Areas

  • Space
  • Space - Satellites