由星载GPS双差相位数据进行CHAMP卫星动力学定轨

Determination of CHAMP Orbit from Onboard GPS Double-Difference Phase Data with Dynamic Method

摘要: 为了确定CHAMP卫星的轨道,由星载GPS数据和IGS跟踪站的GPS数据构造星地相位双差观测量,利用EOP、SGO、时间等数据,对GPS数据进行预处理,包括钟差改正、模糊度解算和周跳探测、卫星姿态改正、天线偏差和相位中心改正等,采用CHAMP卫星受力摄动模型,根据动力学原理,对CHAMP卫星进行实际定轨。与德国GFZ定轨结果PSO相比,本方法定轨结果径向精度为0.285 7 m。对于1 d的重叠轨道,径向轨道差异的RMS为0.095 8 m。对于轨道端点比较,径向轨道差异平均为0.066 6 m。

Abstract: In order to determine the CHAMP's orbit,the onboard GPS data of CHAMP,the GPS data of IGS tracking stations,EOP,SGO and time data are necessary.The GPS data should be pre-processed to correct the clock error,solve the ambiguity,detect the cycle slips,determine the satellite attitude,and calculate the antenna phase center offset and correction.Then the air-ground GPS double-difference phase observations are constructed.The CHAMP's orbit is really determined with the dynamic method.Comparing with the PSO from German GFZ,the precision(RMS) in the radial direction is 0.285 7 m.For the 1-day overlapping orbit,the RMS of radial orbit difference is 0.095 8 m.Comparing the orbit endpoints,the mean difference of radial orbit is 0.066 6 m.