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A GPS measurement system for precise satellite tracking and geodesyNASA is pursuing two key applications of differential positioning with the Global Positioning System (GPS): sub-decimeter tracking of earth satellites and few-centimeter determination of ground-fixed baselines. Key requirements of the two applications include the use of dual-frequency carrier phase data, multiple ground receivers to serve as reference points, simultaneous solution for use position and GPS orbits, and calibration of atmospheric delays using water vapor radiometers. Sub-decimeter tracking will be first demonstrated on the TOPEX oceanographic satellite to be launched in 1991. A GPS flight receiver together with at least six ground receivers will acquire delta range data from the GPS carriers for non-real-time analysis. Altitude accuracies of 5 to 10 cm are expected. For baseline measurements, efforts will be made to obtain precise differential pseudorange by resolving the cycle ambiguity in differential carrier phase. This could lead to accuracies of 2 or 3 cm over a few thousand kilometers. To achieve this, a high-performance receiver is being developed, along with improved calibration and data processing techniques. Demonstrations may begin in 1986.
Document ID
19860036361
Document Type
Reprint (Version printed in journal)
Authors
Yunck, T. P. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Wu, S.-C. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Lichten, S. M. (California Institute of Technology Jet Propulsion Laboratory, Pasadena, United States)
Date Acquired
August 12, 2013
Publication Date
December 1, 1985
Publication Information
Publication: Journal of the Astronautical Sciences
Volume: 33
ISSN: 0021-9142
Subject Category
GEOPHYSICS
Distribution Limits
Public
Copyright
Other