精确标定导航卫星发射天线相位中心对于高精度GNSS(global navigation satellite system)数据处理十分重要,对于低轨卫星(low earth orbit,LEO)精密定轨更是如此。本文以GPS为例,首先探讨了一种基于LEO简化动力学精密定轨残差建模的方法,对导航卫星发射天线相位中心变化(phase center variation,PCV)进行标定,与IGS08_1745.atx(international GNSS service,IGS)的PCV比较结果表明,本文所得PCV在天底角低于14°部分与IGS的PCV差异约1mm,并且有效地将天底角(nadirangle)拓展至17°;最后采用多种方案讨论了导航卫星PCV对JASON-2精密定轨的影响。结果表明,导航卫星PCV可导致1~2cm的定轨误差。其中利用本文所得PCV可实现3D-RMS约3cm、径向约1cm的定轨精度,与采用IGS的PCV定轨精度相当,本方法可为北斗卫星发射天线相位中心变化的标定提供参考。
Accurate calibration of GPS satellite transmitting antenna phase centers is very important for precise GNSS data processing, as well as for precise orbit determination of LEOs. This paper takes GPS as the starting point for a new method based on residuals from space-borne data to calibrate GPS satellite antenna PCVs. PCVs obtained from JASON-2 GPS residuals are compared with igs08_ 1745. atx. Results show that the agreement is about 1 mm-2 mm below 14° , and the estimated GPS PCVs values is extended up to nadir angle of precisely 17°. Several schemes were designed to consider the effects of GPS PCVs on the precise orbit determination of LEOs. Results show that errors about 2 cm can be caused by GPS PCVs. The resulting PCVs obtained the same accuracy orbits as ones using IGS PCVs, with accuracy at about 3cm in 3D, and lcm in the radial direction. The method used in this paper can provide references for calibrating the antenna phase center variation of BEIDOU satellites.