中文摘要：

针对深空探测器在行星际飞行的轨道确定问题，研究了一种基于视线矢量的自主导航算法．结合深空探测任务的特点，以太阳视线矢量和地球视线矢量作为导航系统的观测量，在详细分析太阳敏感器测量原理的基础上，给出了太阳视线矢量的观测模型及其观测误差表达式．通过分析导航相机观测原理，给出像元像线观测模型，并推导了地球视线矢量的观测误差．根据惯性空间内视线矢量间的几何关系，详细推导了探测器的位置矢量及其误差表达式，结合非线性扩展卡尔曼滤波建立自主导航算法．利用深度撞击任务的实际飞行数据对本文提出的深空自主导航算法进行了仿真验证．

英文摘要：

In this paper, an autonomous navigation algorithm is based on Line-of-Sight （LOS） vector in order to solve the orbit determination problem of deep space probe during the interplanetary phase. Considering the characters of the deep space mission, the Sun LOS vector and Earth LOS vector are served as the measurement of the navigation system. Following the measurement principle of the Sun senor, the corresponding measurement model and error expression of Sun LOS vector are derived. The measurement model of the pixel and line in the camera coordinates is given through the analysis of the navigation camera, and the measurement error of Earth LOS vector is deduced. The position vector and its error expression are derived in detail based on the geometric relation of the LOS vectors in the inertial space. Finally, the autonomous navigation algorithm is established utilizing extended Kalman filter, and is demonstrated by the practical data of Deep Impact mission.