摘要
针对卫星钟差预报(SCB)中周期项选取方法存在的问题,在分析卫星钟周期波动特性的基础上,给出了正确的周期项选取方法,并与现有方法进行了比较.利用IGS(International GNSS Service)的卫星钟差数据,比较分析了二次多项式加周期项模型与传统模型的预报精度.从理论上分析了周期项对传统模型的改善程度及适用条件.结果表明:按照提出方法得到的周期项更符合实际,将其应用于钟差预报时能获得更高的预报精度,大量仿真实验还表明卫星钟周期性波动相对较大时周期项对传统模型有明显改善.
In order to solve the issues of selecting periodic items existing in prediction of satellite clock bias （SCB）, the problems of traditional selecting methods are analyzed, and a proper selecting method is put forward. To obtain periodic items, the spectrum analysis technology is carried out in this paper on a group of clock products of the International GNSS Service （IGS） for the satellite clocks, PRN01, PRN09, PRNll, and PRN27. On the basis of the method of periodic items selecting, a prediction model, i.e. quadratic polynomial with periodic items, is studied, and given with specific steps. Besides, a comparison of the proposed model and the traditional model, is given to illustrate the influence of periodic items on the SCB prediction. Finally, the improvement in prediction accuracy by using pe- riodic items is conducted in theory. And the prerequisite for periodic term is analyzed. The result shows that the selected periodic items are in accordance with the actual situation, and a higher accuracy is gained by employing the proposed model. However, a large number of simulations demonstrate that a significant improvement can only be obtained when the satellite clock has a marked periodic variation behavior.
出处
《天文学报》
CSCD
北大核心
2013年第3期282-290,共9页
Acta Astronomica Sinica
关键词
天体测量学
时间
天体力学
轨道计算和定轨
方法
数值
astrometry, time, celestial mechanics： orbit calculation and determination,methods： numerical
