一种近地航天器脉冲星地固系动力学定轨方法

摘要

To improve the navigation accuracy by properly incorporating the Earth gravity model in the near-Earth spacecraft pulsar-based navigation,this paper proposes the method of dynamic orbit determination in the Earth-fixed reference frame.Based on the geopotential and the inertial force model,the obit dynamics equation is constructed in the Earth-fixed reference frame.The pulse phase measurement is used in the extended Kalman filter for real-time estimation. The proposed method decreases the nonlinearity of the dynamics equation,which is especially applicable for the geostationary satellites.Numerical simulation validates the effectiveness and the accuracy of this method.%为改善近地航天器脉冲星导航的定轨精度，设计一种地固系动力学定轨方法。该方法结合了更精确的地球引力场模型，在求地球引力势梯度基础上引入惯性力，建立了地固系下轨道动力学方程；并结合脉冲相位量测，使用扩展卡尔曼滤波实现航天器轨道参数实时估计。此方法可以降低动力学方程非线性度，尤其适用于地球静止轨道卫星。通过数学仿真校验了新方法的有效性与精度。