The Application of Coherent Local Time for Optical Time Transfer and the Quantification of Systematic Errors in Satellite Laser Ranging
The Application of Coherent Local Time for Optical Time Transfer and the Quantification of Systematic Errors in Satellite Laser Ranging
复制标题
相干本地时间在光学时间传递中的应用以及卫星激光测距系统误差的量化
DOI：
10.1007/s11214-017-0457-2
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发表时间：
2018-02
影响因子：
10.3
通讯作者：
K. U. Schreiber;J. Kodet
中科院分区：
文献类型：
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作者：
K. U. Schreiber;J. Kodet
高精度的时间和稳定的参考频率是空间大地测量的基本要求。卫星激光测距(SLR)是其中的一种技术，它不同于甚长基线干涉测量(VLBI)、全球导航卫星系统(GNSS)以及最终的多普勒轨道成像和卫星综合无线电定位(DORIS)等所有其他应用，因为它是一种光学双向测量技术。这意味着在测量技术覆盖的距离两端之间不需要时钟同步过程。在光速各向同性的假设下，SLR建立了迄今为止爱因斯坦同步过程的唯一实际实现。因此，它是一种强大的时间传递技术。然而，为了在两个远程时钟之间传递时间，还必须严格控制测距过程中所有可能的信号延迟。本文讨论了时间和频率在SLR中的作用，以及在解决地面和空间之间的时间传递之前的误差源。由于需要改进信号延迟控制，导致对大地观测站Wettzell的当地时间和频率分布进行了重大重新设计。闭合测量现在可以用来识别和消除单反测量中的系统误差。
Highly precise time and stable reference frequencies are fundamental requirements for space geodesy. Satellite laser ranging (SLR) is one of these techniques, which differs from all other applications like Very Long Baseline Interferometry (VLBI), Global Navigation Satellite Systems (GNSS) and finally Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) by the fact that it is an optical two-way measurement technique. That means that there is no need for a clock synchronization process between both ends of the distance covered by the measurement technique. Under the assumption of isotropy for the speed of light, SLR establishes the only practical realization of theEinstein Synchronizationprocess so far. Therefore it is a powerful time transfer technique. However, in order to transfer time between two remote clocks, it is also necessary to tightly control all possible signal delays in the ranging process. This paper discusses the role of time and frequency in SLR as well as the error sources before it address the transfer of time between ground and space. The need of an improved signal delay control led to a major redesign of the local time and frequency distribution at the Geodetic Observatory Wettzell. Closure measurements can now be used to identify and remove systematic errors in SLR measurements.