LEO Satellite Clock Modeling and Its Benefits for LEO Kinematic POD

doi:10.3390/rs15123149

	LEO Satellite Clock Modeling and Its Benefits for LEO Kinematic POD
	Wang, Kan 1,2; El-Mowafy, Ahmed 3; Yang, Xuhai 1,2
	2023-06-01
发表期刊	REMOTE SENSING
卷号	15 期号:12 页码:22
摘要	High-accuracy Low Earth Orbit (LEO) satellite clock and orbital products are preconditions to realize LEO augmentation for high-accuracy GNSS-based positioning on the ground. There is a high correlation between the orbit and clock parameters in the kinematic Precise Orbit Determination (POD) process. While future LEO satellites are planned to be equipped with better clocks, the benefits of modeling high-stability LEO satellite clocks are not yet thoroughly investigated, particularly when mid- to long-term systematic effects induced by the complex LEO relativistic effects and the external environment remain in the clocks. Through clock modeling, this study attempts to reduce not only the short-term noise of radial kinematic orbits, but also mis-modeled effects caused by, e.g., real-time GNSS orbital and clock errors. To explore the benefits of clock modeling, the clocks need to be first detrended by the mid- to long-term systematic effects. While over-detrending limits the orbital improvements, weak detrending would also hamper strong clock modeling and easily lead to performance degradations. A balance between the strengths of the detrending and the model thus needs to be investigated for different clock types. In this study, the Piece-Wise Linear (PWL) model of different time lengths and a 2.5-state filter with different strengths (h values) are tested using real data from GRACE FO-1 with an Ultra-Stable Oscillator (USO) on board. Using the CNES real-time GPS products, it was found that when detrending the clocks with a smoothing window of 300 to 500 s, one could generally expect an improvement larger than 10% in the estimation of radial orbits when applying a PWL model with a length from 300 to 1200 s. Improvements of this size can also be expected when using the 2.5-state model with h(-1) (for Flicker Frequency Noise) from 10(-28) to 10(-30).
关键词	Low Earth Orbit (LEO) clock modeling Precise Orbit Determination (POD) USO
资助者	National Time Service Center, Chinese Academy of Sciences (CAS) ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; CAS "Light of West China" Program ; CAS "Light of West China" Program ; Shaanxi Province Key Ramp;D Program Project ; Shaanxi Province Key Ramp;D Program Project ; Australian Research Council-discovery project ; Australian Research Council-discovery project ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; CAS "Light of West China" Program ; CAS "Light of West China" Program ; Shaanxi Province Key Ramp;D Program Project ; Shaanxi Province Key Ramp;D Program Project ; Australian Research Council-discovery project ; Australian Research Council-discovery project ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; CAS "Light of West China" Program ; CAS "Light of West China" Program ; Shaanxi Province Key Ramp;D Program Project ; Shaanxi Province Key Ramp;D Program Project ; Australian Research Council-discovery project ; Australian Research Council-discovery project ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; CAS "Light of West China" Program ; CAS "Light of West China" Program ; Shaanxi Province Key Ramp;D Program Project ; Shaanxi Province Key Ramp;D Program Project ; Australian Research Council-discovery project ; Australian Research Council-discovery project
DOI	10.3390/rs15123149
关键词[WOS]	PRECISE ORBIT DETERMINATION ; LOW EARTH ORBITERS ; TIME
语种	英语
资助项目	National Time Service Center, Chinese Academy of Sciences (CAS)[E167SC14] ; National Natural Science Foundation of China[12073034] ; CAS "Light of West China" Program[XAB2021YN25] ; Shaanxi Province Key Ramp;D Program Project[2022KW-29] ; Australian Research Council-discovery project[DP 190102444]
资助者	National Time Service Center, Chinese Academy of Sciences (CAS) ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; CAS "Light of West China" Program ; CAS "Light of West China" Program ; Shaanxi Province Key Ramp;D Program Project ; Shaanxi Province Key Ramp;D Program Project ; Australian Research Council-discovery project ; Australian Research Council-discovery project ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; CAS "Light of West China" Program ; CAS "Light of West China" Program ; Shaanxi Province Key Ramp;D Program Project ; Shaanxi Province Key Ramp;D Program Project ; Australian Research Council-discovery project ; Australian Research Council-discovery project ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; CAS "Light of West China" Program ; CAS "Light of West China" Program ; Shaanxi Province Key Ramp;D Program Project ; Shaanxi Province Key Ramp;D Program Project ; Australian Research Council-discovery project ; Australian Research Council-discovery project ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Time Service Center, Chinese Academy of Sciences (CAS) ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; CAS "Light of West China" Program ; CAS "Light of West China" Program ; Shaanxi Province Key Ramp;D Program Project ; Shaanxi Province Key Ramp;D Program Project ; Australian Research Council-discovery project ; Australian Research Council-discovery project
WOS研究方向	Environmental Sciences & Ecology ; Geology ; Remote Sensing ; Imaging Science & Photographic Technology
WOS类目	Environmental Sciences ; Geosciences, Multidisciplinary ; Remote Sensing ; Imaging Science & Photographic Technology
WOS记录号	WOS:001018306600001
出版者	MDPI
引用统计
文献类型	期刊论文
条目标识符	http://210.72.145.45/handle/361003/14205
专题	高精度时间传递与精密测定轨研究室
通讯作者	Wang, Kan
作者单位	1.Chinese Acad Sci, Natl Time Serv Ctr, Xian 710600, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Curtin Univ, Sch Earth & Planetary Sci, Perth, WA 6845, Australia
推荐引用方式 GB/T 7714	Wang, Kan,El-Mowafy, Ahmed,Yang, Xuhai. LEO Satellite Clock Modeling and Its Benefits for LEO Kinematic POD[J]. REMOTE SENSING,2023,15(12):22.
APA	Wang, Kan,El-Mowafy, Ahmed,&Yang, Xuhai.(2023).LEO Satellite Clock Modeling and Its Benefits for LEO Kinematic POD.REMOTE SENSING,15(12),22.
MLA	Wang, Kan,et al."LEO Satellite Clock Modeling and Its Benefits for LEO Kinematic POD".REMOTE SENSING 15.12(2023):22.