预警卫星对主动段弹道跟踪算法研究

针对预警卫星视线（LOS，Line-of-Sight）测量下对弹道导弹目标的跟踪问题，传统的方法（如EKF）存在易发散、不稳定的现象。引入一种更为稳健和有效的滤波估计算法UKF，其通过特别选取一些样点，给出随机变量经过非线性变化后的均值和方差，从而得到滤波器基于非线性方程的更新，避免了非线性方程的线性化。解析表达了导弹推力加速度值和导弹在重力作用下姿态的变化特性，提出了基于弹体旋转的主动段运动方程。通过Mortte-Carlo仿真，与其它算法比较，说明该算法跟踪性能更好，在空间预警系统应用中具有较好的适应能力。

Research on the Trajectory Tracking in Boost Phase from Satellite Observations

This paper describes trajectory tracking using the satellite LOS measurement. The traditional method has the divergence and unsteadiness. This paper inducts the new robust tracking algorithm, UKF, in which the updating of filter is realized by designing a few points and calculating the propagation of these points via nonlinear functions. This method avoids the linearization of nonlinear equation. This paper analytically expresses the variety of the thrust acceleration and the missile attitude upon gravitation, and then presents the missile rotational model. Using the Monte-Carle simulation, compared with the other methods, the result shows that this technique has the higher accuracy and the apphcability in space based early warning system.