星载GPS低轨卫星几何法精密定轨研究

本文讨论了星载ＧＰＳ接收机为单频情形的代轨卫星几何法定轨，包括载波一相对定轨法和动态网定轨法，并利用Ｔｏｐｅｘ／Ｐｏｓｅｉｄｏｎ卫星星载ＧＰＳ实测数据中Ｌ１载波相位观测值进行验证，结果表明，载波相位相对定轨精度与地面基准站的观测质量有关，其三轨道位置精度为分米级；载波相位动态风定轨精度介于各基准站皮相位相对定轨之间，它相当于在各基准站相对定轨之间加权均衡，而且提高了定轨的可靠性。

THE THEORY OF GPS-BASED GEOMETRIC ORBIT DETERMINATION FOR LOW-EARTH SATELLITE

Methods of single frequency carrier phase-based relative orbit determination(OD) and kinematic network OD for low-earth satellite are developed. From theresults calculated using L1 data collected by GPS/DR onboard Topex/Poseidon,we can draw following conclusions: (a) the accuracy of single frequency carrierphase-based relative OD may attain the order of a few decimeters; (b) the accuracyof relative OD depends on the data quality of ground tracking stations; (c) theaccuracy of kinematic network OD is equavalent to a weighting among relative ODsof different ground tracking stations and can improve the reliability and precisionof OD due to its redundant condition and good geometric configuration.