用非差分方法确定单颗导航卫星的轨道  

Orbit Determination for Single Navigation Satellite Using Non-Difference Method

作　　者：雷辉[1,2,3] 胡小工[1] 黄珹[1] 

机构地区：[1]中国科学院上海天文台 [2]中国科学院研究生院,北京,100049 [3]中国科学院国家授时中心,临潼,710600

出　　处：《天文学进展》2008年第2期192-201,共10页Progress In Astronomy

基　　金：国家自然科学基金(10703011);上海市科学技术委员会资助课题(06DZ22101)

摘　　要：在导航系统中有时需要对单颗导航卫星进行定轨.此时由于无法组成常用的同历元单差或双差以消除卫星钟差或接收机钟差,有必要发展新的定轨策略和精度分析.该文以GPS为例,讨论在不依赖于星站间时间同步的情况下,对单颗导航卫星进行精密定轨.首先分析了GPS卫星钟差以及GPS接收机钟差的特性,发现在一定间隔内钟差主要表现为线性变化,而在去除这一线性项后,非线性钟差在3 m以内.利用GPS的伪距对单颗卫星定轨,在将钟差的主要部分作为测距的偏差和偏差变化率后,伪距测量量等价于常见的测距测量量.在利用等价的测距测量量定轨时可同时解算出偏差和偏差变化率参数.为验证该方案的可行性及其定轨精度,利用实测GPS观测数据进行了试验.结果表明,此种定轨方案定轨的径向精度优于4 m.考虑到GPS接收机的频率信号是由普通的晶振产生的,如果地面接收机采用原子钟提供的频率标准,其钟差的非线性部分将更小.模拟计算表明,采用本方案可以期望得到更高的定轨精度.In some situation of navigation system, such as there is only one satellite in early stages or some satellite was carried out orbit control or maneuver, we need determine the orbit of single navigation satellite. Temporarily single difference or double difference in common use can＇t build up to eliminates the clock error of satellite or receiver, it is necessary develop new strategy of orbit determination and analyses of precision. This paper discussed the orbit determination for single navigation satellite independent of time synchronization, taking the GPS navigation system as background. First, the clock error of satellite and receiver are analyzed; there is an obvious linear item in them and the residuals is less than 3 meters when such item is removed. This paper perform orbit determination using pseudo-range data, the pseudo-range is equal to range if the main part of clock error seemed as range bias and bias drift. Together with orbit determination, the range bias and bias drift are estimated. To verify the feasibility and accuracy of this strategy, we perform orbit determination using real GPS data. It indicates that the precision in radial of this orbit determination scheme is better than 4 m. The stability of the clock error would be better, considering the frequency standard of the signal and the receivers for orbit determination is provided by atomic clock. We perform orbit determination using simulation data; it indicates that better precision can be expected using this orbit determination strategy.

关 键 词：天体测量学 非差 导航卫星 定轨 测距偏差 

分 类 号：P135[天文地球—天体力学]