Computation of Consistent Geodetic Reference Frames by Combination of Space Geodetic Techniques over a Long Time Period (DGFI)
It is the goal of this work package to compute and to validate rigorously combined multi-year solutions based on the observation time series of the different techniques (daily or weekly SINEX files) provided by WP3000. The major result of these multi-year solutions will be consistent, highly accurate realizations of the terrestrial and celestial reference system, i.e. station coordinates and velocities (TRF: Terrestrial Reference Frame) and quasar coordinates (CRF: Celestial Reference Frame). A refined realization of these reference frames also requires a proper handling of non-linear motions of stations and temporal variations of quasars.
Work package WP4000 is divided into the intra-technique combination (WP4100, combinations within one observation technique), inter-technique combination (WP4200, combination of different techniques), comparisons within this joint project (WP4300, internal comparisons), and external comparisons and validation (WP4400). Within this joint project, WP4000 is performed at DGFI (with the DOGS software) and at GFZ (with the Bernese GPS software), whereas GIUB contributes to the intra-technique combination (WP4100) and thereby concentrates on the combination of VLBI observation series. This redundancy is mandatory and ensures an optimal control and validation of the developments and the combination results.
Results of Work Package 4000 (German)