Computation of a Terrestrial Reference Frame based on homogeneously processed data of different space geodetic techniques
The computation of a Terrestrial Reference Frame (TRF) is done by combining time series derived from the space geodetic techniques VLBI, SLR, GPS and DORIS. To obtain a TRF of high accuracy, consistency of the different techniques is required, which was not completely achieved for the current ITRF2005 solution. To guarantee for consistency, the observations of the different techniques have to be analyzed using software packages, which are adapted concerning modelling and parameterization. The presented TRF solution is based on such homogeneously processed data, that were generated within the German GGOS-D project, a joint activity of four geodetic institutions. The applied combination model consists of two main parts. In the first one, the computation of multi-year solutions per technique is performed. It comprises the generation and analysis of the station position time series to identify systematic effects, e.g. jumps and periodical variations, the detection of outliers and finally the accumulation of the time series using the results of the time series analysis to model the temporal behavior of the station positions. In the second part the different techniques are combined to a terrestrial reference frame solution. The major issues of the combination process are: the selection of co- location sites, the estimation of relative weighting factors to consider differences between the variance levels of the techniques and the realization of the geodetic datum. The combination procedure is presented and the TRF results are discussed in terms of consistency and accuracy.
AGU Fall Meeting Abstracts
- Pub Date:
- December 2007
- 1229 Reference systems