Coordination Funds

该研究单位的目标是通过将几何系统与时间联系起来，高精度地长期稳定地实现大地测量参考系，从而显示出一条通向一致实现时空的明确道路。全球参照系是许多应用的计量基础，从量化地球系统在所有定位任务中的变化过程到地面和空间导航。鉴于这些任务具有高度的社会相关性，联合国于2015年2月26日通过了联合国可持续发展全球大地测量参考框架(GGRF)决议。GGRF包括几何形状、地球重力场(包括物理高度)和地球相对于天球参考系的方位。该研究单位将为实施这样一个综合全球全球气候变化框架作出根本性贡献。参照系的最高精确度和长期稳定性对于量化诸如海平面变化等长期趋势至关重要。这些全球参照系是通过各种空间大地测量技术的测量结合起来实现的，这些技术结合在一起，在一些全球分布的核心站，如大地观测站Wettzell和美国国家航空航天局(NASA)的综合基准站进行大地测量。由于当地的测量只参考几何而不参考实际参考，系统误差是不可避免的。我们建议将时间相干性建立为一种新的真实纽带，以便也消除空间大地测量中持续存在的系统误差。利用通用时钟和地面基准进行闭合测量，并量化这一新方法。总之，通过这个研究单位，我们想要利用引入光学钟和长距离光纤线路向空间大地测量传递时间和频率所带来的巨大机会，利用空间原子钟系统(ACE)，以及最后但并非最不重要的一种新的时间和频率分配系统，包括整个大地观测站。

The goal of this research unit is a highly accurate long-term stable realization of the geodetic reference systems by linking the geometric systems to time, thus demonstrating a clear path towards a consistent realization of space-time. Global reference frames are the metrological basis for a multitude of applications, reaching from the quantification of change processes in system Earth over all positioning tasks to terrestrial and space navigation. In view of the high societal relevance of these tasks, the United Nations adopted the UN resolution Global Geodetic Reference Frame for Sustainable Development (GGRF) on February 26, 2015. The GGRF includes the geometry, the gravity field of the Earth (including physical heights) and the orientation of the Earth with respect to the celestial reference frame. This research unit will provide fundamental contributions to the implementation of such an integrated GGRF. Highest accuracy and long-term stability of the reference frame are of paramount importance for the quantification of long-lasting trends, such as sea level changes. These global reference systems are realized by the combination of measurements from a diversity of space geodetic techniques, tied together employing geodetic local surveys at a number of globally distributed core stations, such as the Geodetic Observatory Wettzell (GOW) and the integrated fundamental stations of the National Aeronautics and Space Administration (NASA). Since the local surveys only refer to the geometric but not to the actual reference, systematic errors are inevitable. We propose to establish time coherence as a novel true tie in order to also remove persisting systematic errors from the measurements in space geodesy. Closure measurements utilizing a common clock and ground reference proof and quantify this novel approach. In summary, with this research unit we want to exploit the great opportunity that is presented by the introduction of optical clocks and long distance optical fiber lines for time and frequency transfer to space geodesy, the utilization of the Atomic Clock Ensemble in Space (ACES) and last but not least a novel time and frequency distribution system, enclosing an entire geodetic observatory.