X射线源/地心矢量观测的卫星自主导航应用

针对X射线探测器的卫星自主导航应用,提出基于X射线源/地心矢量观测的航天器自主天文导航方法。研究了X射线源/地心矢量自主导航原理并给出自主导航系统方案。通过X射线源和地心矢量提取,合成了X射线星光角距和星光仰角观测模型。对X射线源矢量方位观测误差和地心矢量方位观测误差引起的系统观测量残差进行了理论分析,并将其建模为缓变量。建立了卫星运动状态方程模型，并将无迹卡尔曼滤波(unscented Kalman filter,UKF)算法应用于自主导航过程中,针对观测量周期与导航周期异步的情况给出了导航解算方案。近地圆轨道卫星的自主导航仿真结果验证了该方法的有效性。

Satellite autonomous navigation using X-ray source/geocentric vector observation

Aiming at the application of X-ray detector in satellite autonomous navigation,a spacecraft autonomous celestial navigation method based on X-ray source/geocentric vector observation is proposed. The principle of X-ray source/geocentric vector autonomous navigation is studied and the autonomous navigation system scheme is presented. The system observation residual which is caused by X-ray source vector orientation error and Earth-central vector orientation error is theoretically analyzed,and then the residual is modeled as mitigable value. The satellite state model equation is established and the unscented Kalman filter (UKF) algorithm is applied to the autonomous navigation process. Navigation algorithm proposal is carried out considering the asynchronism of the observation period and the navigation period. Near earth satellite autonomous navigation simulation results verify the effectiveness of the proposed method.