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在利略太空部分为框架链接的VLBI发射器的最佳分布
1Department of Geodesy and Geoinformation, TU Wien, 1040 Vienna, Austria.
概括
配备VLBI发射器的利略卫星允许直接轨道估计和框架绑定实现. 模拟显示,在使用2-3颗卫星和30%-40%的卫星观测比率的情况下,最优准确度.
科学领域:
- 地质测量是指地质测量.
- 卫星导航 卫星导航 卫星导航 卫星导航
- 无线电天文学 无线电天文学
背景情况:
- 利略卫星可以配备VLBI发射器 (VT),用于直接轨道估计.
- 这使得通过将空间联系转移到地球表面,可以在地质站点实现框架绑定.
研究的目的:
- 通过使用利略卫星的VLBI观测来评估框架结合实现的准确性.
- 从这些观测中模拟站点坐标的估计.
主要方法:
- 模拟VLBI对利略卫星和类星体的观测.
- 对站点坐标估计准确性的分析.
- 对不同数量的卫星和观测比率的评估.
主要成果:
- 在同一平面上使用2-3颗卫星实现最佳准确性.
- 最佳的卫星观测比率为30-40%,用于平衡站坐标和热层参数估计.
- 具有两颗卫星的7.5-10毫米 (水平) 和9.5-12毫米 (垂直) 的重复性.
- 通过第三颗卫星进行了进一步的改进,将误差减少了多达2-4毫米.
结论:
- 利略卫星的VLBI观测提供了直接轨道估计和框架结合实现的可行方法.
- 配备的卫星数量和观测策略显著影响准确性.
- 在利略星座的10天重复周期中保持一致的精度.
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