一种校准编目定轨初始速度的方法 1)
A METHOD TO CORRECT CATALOG ORBIT DETERMINATION VELOCITY 1)
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摘要: 对于大批量空间目标,监测资源有限,测轨数据稀疏,导致编目定轨结果误差较大。本文分析了不同轨道类型的编目轨道预报误差演化特性,分析结果表明,轨道预报误差主要分布在沿迹方向,且主要是由于大气阻力摄动模型误差和初始径向速度误差引起的。进一步的理论推导显示,在忽略初始位置误差的假设条件下,轨道初值误差引起的预报位置误差前后具有近似对称特性,利用仿真数据,验证了近似对称特性的正确性。基于上述分析,本文提出了一种校准编目定轨初始速度的方法,即通过减小向前预报的位置与已知位置的偏差来迭代地校准定轨结果的速度,从而提高目标向后预报的轨道精度。利用实际轨道数据的试验结果表明,该方法对于采用稀疏数据的近圆轨道目标定轨结果修正效果明显,可以有效改进自主编目定轨结果的精度,对提高大批量空间目标的编目管理能力具有重要价值。Abstract: For the utilization space activities, the number of man-made space objects increases fast. Due to the limitation of the detect resource, the detected data of the mass space objects are less than what is adequate, which means a worse accuracy of the orbital calculated result. In this paper, the space objects are classified by the orbit altitude, and the influence on different perturbation factors are analyzed. It is indicated that with the perturbation model,the error of the atmospheric drag and the velocity of the initial radial direction is the major cause of the orbit propagation error, which is distributed along the track. By ignoring the error of the initial position, the values before and after the perturbation error caused by the orbit initial position error are approximately symmetric, which is confirmed in the simulation experiment. A method is then proposed to correct the catalog orbit determination velocity by reducing the position error propagated before the given point to improve the position precision propagated after the given point. In the experiment with the real observation data, the method works effectively in modifying the orbital result within the sparse data of the near-circular space object, and the accuracy of the self-catalogue space object is improved. The method improves the ability of the catalogue managing the space object.