发表机构
Institut für Erdmessung, Leibniz Universität Hannover; Forschungseinrichtung Satellitengeodaesie, Technical University of Munich（汉诺威莱布尼茨大学地球测量研究所; 慕尼黑工业大学卫星大地测量研究中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过模拟ACES任务中的卫星钟比较，验证了利用引力红移信号确定地面站间物理高度差的可行性，光学链路可实现厘米级精度，展示了大陆尺度遥感测高的潜力。
AI 中文摘要
利用高稳定度原子钟确定物理高度差已成为相对论大地测量学中的一种新方法，该方法将引力红移作为地球位势差的直接可观测物理量。在本研究中，我们探讨了基于国际空间站上的空间原子钟组（ACES）进行卫星钟比较的可行性，该任务可通过微波链路（MWL）和光学链路（ELT）实现时间传递。由于目前尚无运行中的光学数据，我们开展了对真实ACES观测场景的全尺度综合模拟，其中包括钟和链路的详细噪声模型。采用基于斜率估计的方法处理钟比较时间序列，以提取相对论红移信号并推导地面站之间的高度差。我们在准共视、非共视和分段非共视三种配置下评估了该方法的性能，其中分段非共视配置将观测期划分为较短的区间。结果表明，光学链路能够实现更快的收敛，在数天内即可达到分米级的高度精度，在更长时间内可达到厘米级精度，而微波链路受噪声和偏差的影响更为显著。非共视处理显著提高了观测可用性，且精度损失较小，分段方法则为更大规模的地面网络提供了稳健的解决方案。这些发现证明了基于卫星的钟比较作为一种遥感技术，在确定大陆尺度物理高度差方面具有巨大潜力。
英文摘要
The determination of physical height differences using highly stable atomic clocks has emerged as a novel approach in relativistic geodesy, exploiting the gravitational redshift as a direct observable of geopotential differences. In this study, we investigate the feasibility of satellite-based clock comparisons using the Atomic Clock Ensemble in Space (ACES) onboard the International Space Station, which enables time transfer via microwave (MWL) and optical (ELT) links. Since operational optical data are not yet available, a comprehensive full-scale simulation of realistic ACES observation scenarios is performed, including detailed noise models of clocks and links. A slope-based estimation method is applied to time series of clock comparisons in order to extract the relativistic redshift signal and derive height differences between the ground stations. The performance of the approach is evaluated for quasi-common view, non-common view, and split non-common view configurations, where the latter divides the observation period into shorter intervals. The results show that optical links enable faster convergence and can achieve height accuracies at the decimeter level within a few days and at the centimeter level over longer periods, while microwave links are more strongly affected by noise and bias contributions. Non-common view processing significantly increases observation availability with only minor loss in accuracy, and the split approach provides robust solutions for larger networks. These findings demonstrate the strong potential of satellite-based clock comparisons as a remote-sensing technique for determining physical height differences on a continental scale.
Comments21 pages, 9 figures. Submitted to Remote Sensing
