GPS Solutions

, Volume 10, Issue 1, pp 45–55 | Cite as

Accuracy of OPUS solutions for 1- to 4-h observing sessions

  • T. Soler
  • P. Michalak
  • N. D. Weston
  • R. A. Snay
  • R. H. Foote
Original Article

Abstract

We processed 30 consecutive days of Global Positioning System (GPS) data using the On-line Positioning Users Service (OPUS) provided by the National Geodetic Survey (NGS) to determine how the accuracy of derived three-dimensional positional coordinates depends on the length of the observing session T, for T ranging from 1 h to 4 h. We selected five Continuously Operating Reference Stations (CORS), distributed widely across the USA, and processed the GPS data for each with corresponding data from three of its nearby CORS. Our results support the current OPUS policy that recommends using a minimum of 2 h of static GPS data. In particular, 2 h of data yielded a root mean square error of 0.8, 2.1, and 3.4 cm in the north, east, and up components of the derived positional coordinates, respectively. Results drastically improve for solutions containing 3 h or more of GPS data.

Keywords

GPS Processing services OPUS  Position relative to observation time 

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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • T. Soler
    • 1
  • P. Michalak
    • 2
  • N. D. Weston
    • 1
  • R. A. Snay
    • 1
  • R. H. Foote
    • 1
  1. 1.National Geodetic SurveyNOAASilver SpringUSA
  2. 2.Warsaw University of Technology, Institute of Geodesy and Geodetic AstronomyWarsawPoland

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