THE GEODYSSEA NETWORK: GFZ RESULTS AND DATUM DEFINITION




D. ANGERMANN, J. KLOTZ, C. REIGBER, AND P. WILSON 1)



In scope of the GEODYSSEA project an extensive GPS network has been established in South and South East Asia. In November/December 1994 and April 1996, two large GPS measurement campaigns have been carried out by GFZ and IfAG, in cooperation with many institutions in the host countries.
The GPS data evaluation with the GFZ software EPOS (Earth Parameter & Orbit System) is described. EPOS is based on undifferenced phase- and pseudorange observations for the parameter determination. The GEODYSSEA network stations have been processed simultaneously with selected IGS stations in the form of a regional and global solution with fixed IGS orbits and EOP's resulting in a daily repeatability of the station coordinates in the order of 3-5 mm for the horizontal components and 9 mm for the vertical.
Furthermore the paper deals with the datum definition of the GEODYSSEA network. In this context two major questions are discussed:
  • 1) What is the effect of different IGS orbits on the station coordinates?
  • 2) What is the effect of a regional or global distribution of the IGS stations included in the solution?


    1) GeoForschungsZentrum Potsdam, (GFZ)
    Telegrafenberg A17
    D-14173 Potsdam, Germany



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