基于双频星载GPS数据的LEO卫星运动学定轨研究

摘要

distinctive approach of space-borne GPS technique, and well suited for orbit determination of Low Earth orbiting (LEO) satellites which are strongly perturbed by atmosphere. Firstly, an algorithm of kinematic POD is developed by using the zero-difference space-borne dual-frequency GPS measurements in this paper. And then, how to pre-process the space-borne dual-frequency GPS data and how to set the estimated parameters of kinematic POD are discussed in detail. Finally, the observational data from GRACE (Gravity Recovery And Climate Experiment) satellites covering the whole month of February 2008 are employed to validate the effectiveness and reliability of the method introduced in this paper. It is demon-strated that kinematic POD reaches an accuracy of about 5 cm (with respect to satellite laser ranging), which is at the same level of accuracy as dynamic and reduced-dynamic POD.%运动学定轨是星载GPS特有的定轨方法,该方法不依赖于任何力学模型(地球重力场、大气阻力及太阳辐射压等),尤其适用于受大气阻力影响严重的低轨卫星定轨.基于双频星载GPS数据,研究了运动学定轨原理,讨论了数据预处理方法,建立了一套非差运动学定轨算法.并以GRACE (Gravity Recovery And Climate Experiment)-A、B卫星2008年2月实测数据作为试算验证了本研究方法的有效性和可靠性.GRACE 卫星实测数据计算结果表明:运动学定轨能达到5 cm精度(相对于SLR (Satellite Laser Ranging)),与动力学和简化动力学定轨精度相当.