EOP Products of IVS Analysis Center and Its Precision Evaluation

The organization and subordinate analysis center of International Very Long Baseline Interferometry (VLBI) Service for Geodesy and Astrometry (IVS) are introduced. The types of earth orientation parameters (EOP) products currently released by IVS and the uses of different observation types are summarized systematically. Based on the observation data published from 2010 to 2019, this paper evaluates the overall service capacity of IVS regular observation and intensive observation products of different analysis centers. By constructing the geometric volume formed by observation stations, the relationship between EOP accuracy and the number of observation stations,the distribution of the station network is analyzed, and the calculation accuracy of EOP for different observation types of IVS is counted. Besides, compared with observation data of regional networks in the United States and Europe publically on the website, the differences between the regular observation and intensive observation results of regional networks in different regions and IVS results are analysed. The results showed that the accuracy of EOP is closely related to the distribution of observation stations. The external coincidence precision of the polar motion component determined by IVS conventional observation is better than 0.2mas, the precision of UT1-UTC (the difference between Universal Time (UT1) and Coordinated Universal Time (UTC)) is about 0.015 ms, and the UT1-UTC value of intensive observation has a difference of 0.02--0.03ms from International Earth Rotation Service (IERS) C04 products.\lk The precision of the regional observation network is restricted by the shape of the observation network and the length of the baseline, which is generally inferior to the observation precision of IVS. Among them, the regular and intensive observation results of the Very Long Baseline Array (VLBA) network in the United States are the closest to the global observation results of IVS.