中文摘要：

提出一种利用X射线脉冲星的晕轨道自主导航方法。以高精度星历轨道动力学模型构建晕轨道状态方程，并利用二级微分修正方法获取惯性系下晕轨道的标称轨道。基于微分修正原理，利用X射线脉冲星的导航结果和小推力推进器，对晕轨道探测器进行轨道维持和控制，并以地月系L2点晕轨道为例进行了仿真实验。结果表明，该方法能够有效完成地月系L2点晕轨道探测器的自主导航和轨道维持任务。

英文摘要：

To improve the independent capacity of the halo orbit spacecraft, we propose an autonomous navigation and control system based on the X-ray pulsar-based navigation （XNAV） principle. XNAV theory is applied in the construction of a measurement equation. The full ephemeris dynamical model is adopted in the establishment of the system state equation. We use the two-level differential correc- tion method to obtain a nominal halo orbit in the inertial coordinate system. Based on the differential correction method, the halo orbit spacecraft is controlled using the navigation results from XNAV and the small thrust propeller. A numerical simulation is carried out in the Earth-Moon L2 halo orbit. The results demonstrate that the proposed method can accomplish autonomous navigation and control tasks effectively and the spacecraft can be maintained in the nominal orbit.