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New VLBI2010 scheduling strategies and implications on the terrestrial reference frames
Jing Sun1, Johannes Böhm2, Tobias Nilsson3
1Department of Geodesy and Geoinformation, Vienna University of Technology, Vienna, Austria ; National Key Laboratory of Science and Technology on Aerospace Flight Dynamics, Beijing Aerospace Control Center, Beijing, China.
Journal of Geodesy
|October 30, 2015
Summary
A new source-based scheduling strategy for the VLBI2010 Global Observing System (VGOS) shows comparable performance to traditional methods. This approach offers improved sky coverage and coordinate repeatability for future geodetic applications.
Area of Science:
- Geodesy
- Astronomy
- Computer Science
Background:
- Development of the next-generation VLBI2010 Global Observing System (VGOS) requires advanced scheduling.
- Existing scheduling methods are primarily station-based.
Purpose of the Study:
- Introduce and evaluate a novel source-based scheduling strategy for VLBI2010.
- Investigate the performance implications of this new approach on geodetic schedules.
Main Methods:
- Developed a new scheduling package, Vie_Sched, at Vienna University of Technology.
- Implemented and tested source-based scheduling configurations.
- Compared results with existing VLBI schedules (CONT11) and simulated networks.
Main Results:
- Source-based scheduling with two sources matches station-based performance in observation count, sky coverage, and geodetic parameters.
- Source-based scheduling with four sources improves observation distribution on the celestial sphere for a 16-station network.
- Monte Carlo simulations indicate slightly better repeatability of station coordinates with source-based approaches.
Conclusions:
- The new source-based scheduling strategy in Vie_Sched is a promising alternative for VGOS applications.
- This approach offers comparable or improved performance over traditional methods.
- Further investigation into source-based scheduling configurations is warranted.
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