Consistent Realization of CRF, TRF, and EOP
Abstract
The International Celestial Reference Frame (ICRF) and the International Terrestrial Reference Frame (ITRF) are the realizations of the International Celestial Reference System (ICRS) and the International Terrestrial Reference System (ITRS), respectively. The Earth orientation parameters (EOP) are the parameters linking these two frames, and they are common parameters between the space geodetic techniques whose observations are used to estimate the ICRF and ITRF. Both realizations have been computed separately based on different data sets and by fixing parameters corresponding to the other frame, respectively. This causes inconsistencies between the frames themselves but also between the EOP series resulting from the two computations even though they should be the same. To gain consistency between the two reference frames, a common adjustment is performed. This implies the usage of identical input data, a consistent parameterization and that no parameters are fixed. The realizations benefit in many ways: consistency of the frames and EOP is reached, poorly estimated parameters of one technique could be strengthened by information from the other techniques and consequently the quasar coordinates are improved. In this study, we simultaneously estimate the celestial and terrestrial reference frames together with the full set of EOP based on homogeneously processed GNSS, VLBI, and SLR data over a time period of 11 years (2005.0-2016.0). We present the impact of various combination setups for the EOP and for the local tie handling and discuss the benefits of a simultaneous estimation.
- Publication:
-
42nd COSPAR Scientific Assembly
- Pub Date:
- July 2018
- Bibcode:
- 2018cosp...42E1901K