Vienna contribution to ITRF2020

Abstract

The next realisation of the International Terrestrial Reference System, the ITRF2020 is currently under evaluation. The special analysis center of the International Very Long Baseline Interferometry (VLBI) Service for Geodesy and Astrometry (IVS) at TU Wien (VIE) provided one set of the normal equation systems which was combined together with contributions from other VLBI analysis centers to the VLBI input to ITRF2020. We give a documentation of the included sessions and stations as well as of the parametrisation. In addition to that, our own terrestrial reference frame, VIETRF2020, which is based on the Vienna input to ITRF2020, is presented and compared to previous TRF solutions as well as to preliminary release of ITRF2020, designated as ITRF2020P. As indicated by presentations of the IERS ITRS Product Center, the scale of ITRF2020P was constructed by ”using inner/internal constraints” and as ”average of SLR (1997.7 – 2021.0) and VLBI (selected sessions up to 2014.0)”. This seems to lead to deviations of the scale of our VLBI solution and probably also of the IVS combined data after 2014.0.