DORIS星载实时定轨算法仿真及DSP实现

针对我国高分辨率空间对地观测专项的发展需求,文章在星载多普勒无线电定轨定位（Doppler Orbitography and Radio-positioning Intergrated by Satellite,DORIS）系统的实时定轨算法和流程验证基础上,进行了应用背景限制下的模型简化研究,用数字信号处理器（DSP）实现并验证了其星载实现的可行性和有效性。首先介绍法国星载实时定轨软件（DORIS Immediate Orbit Determination by Embarked,DIODE）及定轨原理,给出星载实时定轨算法的流程。通过网站下载的DORIS接收机搭载星数据,对星载多普勒实时定轨算法的观测量修正部分和卡尔曼滤波定轨算法进行验证。针对星载实现的计算简化要求,对算法中计算量较大的地球非球形引力摄动和章动模型进行研究,对比不同模型复杂度对定轨结果的影响,为定轨算法模型的选取提供依据。最后将移植到DSP的程序运行结果与个人计算机下的仿真结果进行了对比,验证其星载实现满足精度要求,同时运行时间满足实时性要求。对如何提高实时定轨算法的性能,文章给出了后续应用的改进方向。

Simulation and DSP Realization of Real-time Onboard Orbit Determination with DORIS

Considering the demand of domestic high-revolution earth observation system,the paper does some research on the model simplification based on some study of DORIS real-time onboard orbit determination.And the simplified model is proved to be available and effective by the DSP result.First,the paper introduces the DIODE software and principle of realtime orbit determination by using Doppler measurment.The processing flow of onboard realtime orbit determination is given too.Then the paper uses real data on CDDIS web site to validate the measurment correction and Kalman filter orbit determination program on personal computer.For the simplification demand of onboard realization,it studies the effects of different nonspherical gravitational potential perturbation and nutation models upon orbit determination result in order to provide foundation for the realization.The program on DSP satisfies the demand in time and precision.At last,the paper gives some way to improve the performance of the real time orbit determination.