基于光学数据的地球同步轨道目标定初轨方法

INITIAL ORBIT DETERMINATION METHOD OF GEOSYNCHRONOUS TARGET BASED ON OPTICAL DATA

初轨确定的目的主要有两个,一是为空间目标精密轨道计算提供初值,二是为空间目标轨道测量数据相互关联提供初值,其重要性不言而喻。根据地球同步轨道目标的轨道运行特征,在观测弧段内相对测站几乎保持相对静止。由于光学测角数据中缺乏测距的约束,在基于短弧段的光学测角数据采用传统的Laplace方法计算其初始轨道时,由于观测条件的病态性,迭代过程大多发散,难以得到收敛的初轨结果。鉴于上述原因,本文采用遍历搜索轨道半长轴的方法,提出了基于给定半长轴引入伪测距的初轨确定方法,经过仿真数据检验,该方法初轨确定成功率优于95%,有效地解决了地球同步轨道带近圆轨道目标初轨确定过程中迭代难以收敛的问题。

There are two main objectives to determine the initial orbit of space target.One is to provide the initial value for the target precision orbit determination,and the other is to provide the initial value for the correlation of the target observation data.Its importance is self-evident.According to the orbit characteristics of the geosynchronous orbit target,it remains relatively stationary relative to the station during observation arcs.Due to the lack of ranging constraints,when using the optical angular measurements based on short arcs to calculate the orbit by the traditional Laplace method,most iterative processes diverge due to the ill-condition of the observation condition,and it is difficult to obtain the converged result of the initial orbit.For these reasons,this paper adopts the method of orbit semi-major axis traversal search,that is,it introduces pseudo range based on the given semi-major axis into initial orbit determination to supplement the range constraints.Using the simulated data to determine the initial orbits,the success rate of the method is better than 95%.It effectively solves the difficult convergence problem for the near-circular orbit target in geosynchronous orbit zone during the iteratively calculating of the initial orbit process.