International VLBI Service for Geodesy and Astrometry:Earth orientation parameter combination methodologyand quality of the combined products

摘要

The analysis coordinator of the International VLBI Service for Geodesy and Astrometry(IVS) regularly disseminates the official IVS products of Earth orientation parameters(EOPs). For 2 years now, these parameters have been produced by combining datum-free normal equations of up to six IVS analysis centers. In this paper we document thecombination methodology, discuss critical issues, and report on the quality of the products.The agreement of the very long baseline interferometry results with the InternationalGlobal Navigation Satellite Systems (GNSS) Service GPS EOPs is of the order of 18 itsfor length of day and 100 μas (microarc seconds) and 300 μas/d for the polar motioncomponents and their rates, respectively.