动力学模型对简化动力学定轨精度影响仿真

Simulation of Impact of Force Models on Orbiting Accuracy of Reduced-Dynamic Orbit Determination

仔细分析各种力学模型对简化动力学定轨精度影响,对有效提高定轨精度和效率有着重要作用。首先回顾了简化动力学定轨的数学模型,然后结合两个CHAMP卫星星载GPS观测值的仿真算例,分析了各种力学模型对简化动力学定轨精度的影响。结果表明,在简化动力学定轨中,随机脉冲可有效吸收模型误差的影响,即使不考虑难以精确模型化的辐射压、Albedo和大气阻力等的影响,也不会降低定轨精度;使用展开到100阶后的、包含CHAMP跟踪数据的重力场的定轨结果较好。这些结论对简化动力学定轨中力学模型的选取有一定的参考价值。

Careful analyses of impacts of various force models on reduced-dynamic orbit determination may play great role in improving orbiting accuracy and efficiency. Mathematical model of reduced-dynamic orbit was discussed firstly, and then the impacts of various force models on this orbiting method were illustrated with two simulation examples of onboard GPS observations on CHAMP satellite. The simulated results show that the pseudo-stochastic pulses can effectively absorb force model errors in reduced-dynamic orbit determination, Therefore, even if the impacts of some rather implicated force models such as atmospheric drag, direct solar radiation pressure and earth Albedo in reduced-dynamic orbit determination were not considered, the orbit accuracy might not drop. The orbiting results of gravity model with expansions of degree and order 100 or more generated by including some CHAMP tracking data are the best, These conclusions can be a great value in selection of proper force models in reduced-dynamic orbit determination.