RESULTS OF THE WEGENER GPS-92 CAMPAIGN

During the International GPS Service for Geodynamics (IGS) Epoch '92 c ampaign a special sub-campaign was Organized to occupy all WEGENER/MED LAS SLR sites with Trimble SST GPS receivers. This campaign, WEGENER/G PS-92, was initiated by the Institute for Applied Geodesy in cooperati on with Delft University of Technology. The purpose was to observe the whole SLR network, for the first time, with GPS to establish a connec tion between the SLR and GPS reference frames. The dataset was analyze d at the Section Space Research and Technology, using the GIPSY softwa re developed at the Jet Propulsion Laboratory and the Bernese GPS soft ware version 3.4. In the analysis a weighted combination of the orbits provided by the IGS was used to model the motion of the GPS satellite s. The results show a baseline length repeatability, which is a measur e for the precision, in the order of 5 mm. More importantly the GPS co ordinate solution compares very well with the most recent SLR coordina te solution computed at Delft University of Technology. The rms differ ences are 3.8, 5.2 and 12.5 mm in North, East and Up, respectively, us ing 14 sites. It is therefore obvious that GPS will play an increasing ly important role in the monitoring of the deformation and a further d ensification of this network. Especially since starting January 1, 199 4 the IGS has become operational and combined orbits are being produce d and made available with only a few week delay.