Time as observable in integrated ground and space-based GNSS analysis

综合地面和空基 GNSS 分析中可观测的时间

• 批准号: 513034573
• 负责人: Professor Dr. Urs Hugentobler
• 金额: --
• 依托单位: Sektion 1.1: Geodätische Weltraumverfahren
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/513034573?language=en
• 关键词: Time; observable; integrated; ground; space

In the future, ultra-stable clocks will be available on the ground and in space, as well as high-precision time and frequency transmission systems. The goal of this project is to integrate data from these new tools into GNSS geodetic data analysis and to analyse their potential for computing global geodetic precision products derived from GNSS. The project is part of the FOR5456 research group, whose overarching goal is to fully exploit ultra-stable clocks and high-precision frequency and time transmission in geodesy. Within the research group the technology for a lossless link between clocks and GNSS signals will be developed, a high-precision laser space link between the Wettzell (GOW) and Potsdam geodetic observatories will be provided, an ultra-stable optical clock at the GOW will installed and operated, and a link between the Potsdam observatory and the PTB optical clocks in Braunschweig via a compensated optical fiber or, alternatively, an optical clock operated in Potsdam is planned. The resulting opportunities will be investigated in detail in this project with a focus on GNSS. The benefits of lossless linking of GNSS receivers to a common clock on short baselines on the GOW campus and on the long baseline between GOW and Potsdam will be evaluated using closure experiments. In parallel, the full potential of modelling the available ground and space clocks for satellite orbit improvement, decorrelation of estimated parameters, and determination of geodetic parameters in a global network will be explored. The obtained findings are extrapolated to global GNSS networks using simulations and real data to evaluate, by means of the developed methods, the potential of time coherence realized by ground and space links in a global network and of modelling highly stable ground and space clocks for the estimation of global geodetic parameters.

未来，超稳定时钟将在地面和太空中使用，以及高精度的时间和频率传输系统。该项目的目标是将来自这些新工具的数据纳入全球导航卫星系统大地测量数据分析，并分析它们在计算全球导航卫星系统产生的全球大地测量精度产品方面的潜力。该项目是FOR5456研究小组的一部分，该小组的首要目标是充分利用大地测量中的超稳定时钟和高精度频率和时间传输。在研究小组内，将开发时钟和全球导航卫星系统信号之间的无损链接技术，将在Wettzell大地观测站和波茨坦大地观测台之间提供高精度激光空间链接，将在GOW安装和运行一个超稳定光学钟，并计划通过补偿光纤或在波茨坦运行的光学钟，在波茨坦天文台和布伦施韦格的PTB光学钟之间建立一个链接。本项目将详细调查由此产生的机会，重点是全球导航卫星系统。将利用闭合实验评估全球导航卫星系统接收器与全球导航卫星系统接收器在全球海洋观测系统园区的短基线上以及在全球海洋观测组织和波茨坦之间的长基线上无损连接的好处。同时，还将探讨为卫星轨道改进、估计参数的去相关性和确定全球网络中的大地测量参数建立可用地面时钟和空间时钟的全部潜力。利用模拟和真实数据将所获得的结果外推到全球导航卫星系统网络，以通过所开发的方法评估全球网络中地面和空间链路实现的时间一致性的潜力，以及为估计全球大地测量参数而对高度稳定的地面和空间时钟进行建模的潜力。