EOP Precision of the Operational IVS-R1 and IVS-R4 sessions
Abstract
This presentation focuses on the EOP (Earth Orientation Parameter) performance of the operational IVS-R1 and IVS-R4 sessions from 2002 through 2017. The IVS-R series began in January 2002 with a network of five to six stations and increased over time to a network size of 11 to 13 stations in 2017. The formal uncertainties of the R1 and R4 EOP improved over the period of 2002 through 2017. We consider how much this improvement can be attributed to the increased size of the networks, changes in data rate, the number of observed sources, and/or the scheduling parameters. We estimated the observed precision of R1s and R4s by differencing VLBI EOP relative to GNSS. Generally, the observed EOP precision as well as formal EOP uncertainties improved from 2002-2017 by about a factor of 2. However, there is significant variation in observed precision determined for 2-month periods. This precision is better over different time periods, for instance, the precision in the time period around the continuous observing campaign CONT14 was close to the precision of CONT14. We investigate the possible factors that could produce better or worse precision for the R1/R4 networks. Some factors that could help explain the variability in observed EOP precision are network station variation, data loss, observed SNR vs. scheduled SNR, and observed SEFDs vs. scheduled SEFDs. All of these factors are examined in our analysis of the performance of the R1 and R4 series from 2002 through 2017.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.G33C0695T
- Keywords:
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- 1229 Reference systems;
- GEODESY AND GRAVITYDE: 1299 General or miscellaneous;
- GEODESY AND GRAVITY