The effect of tracking network configuration on Global Positioning System (GPS) baseline estimates for the CASA (Central and South America) Uno experiment

Journal Article · Sun Apr 01 04:00:00 EDT 1990 · Geophysical Research Letters (American Geophysical Union); (United States)

DOI:https://doi.org/10.1029/GL017i005p00647· OSTI ID:5455587

Wolf, S K; Dixon, T H ^[1]; Freymueller, J T ^[2]

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1. California Institute of Technology, Pasadena (USA)
2. Univ. of South Carolina, Columbia (USA)

Geodetic monitoring of subduction of the Nazca and Cocos plates is a goal of the CASA (Central and South America) Global Positioning System (GPS) experiments, and requires measurement of intersite distances (baselines) in excess of 500 km. The major error source in these measurements is the uncertainty in the position of the GPS satellites at the time of observation. A key aspect of the first CASA experiment, CASA Uno, was the initiation of a global network of tracking stations minimize these errors. The authors studied the effect of using various subsets of this global tracking network on long (>100 km) baseline estimates in the CASA region. Best results were obtained with a global tracking network consisting of three U.S. fiducial stations, two sites in the southwest pacific and two sites in Europe. Relative to smaller subsets, this global network improved baseline repeatability, resolution of carrier phase cycle ambiguities, and formal errors of the orbit estimates. Describing baseline repeatability for horizontal components as {sigma}=(a{sup 2} + b{sup 2}L{sup 2}){sup 1/2} where L is baseline length, the authors obtained a = 4 and 9 mm and b = 2.8{times}10{sup {minus}8} and 2.3{times}10{sup {minus}8} for north and east components, respectively, on CASA baselines up to 1,000 km in length with this global network.

• OSTI ID: 5455587
• Journal Information: Geophysical Research Letters (American Geophysical Union); (United States), Journal Name: Geophysical Research Letters (American Geophysical Union); (United States) Vol. 17:5; ISSN GPRLA; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
CENTRAL AMERICA
CONFIGURATION
CONTINENTAL CRUST
DATA ANALYSIS
DEFORMATION
EARTH CRUST
GEODETIC SURVEYS
GEOPHYSICAL SURVEYS
LATIN AMERICA
MEASURING INSTRUMENTS
MONITORING
MONITORS
PLATE TECTONICS
POSITIONING
REMOTE SENSING
SATELLITES
SOUTH AMERICA
SUBDUCTION ZONES
SURVEYS
TECTONICS