利用预报误差分布拟合实现卫星历史轨道机动检测的方法

Method to detect satellite historical orbit maneuver based on fitting of prediction error distribution

轨道机动会引起在轨卫星的轨道异常,是空间态势感知的重点关注对象之一。为此,提出一种从卫星的两行轨道要素编目数据中检测历史机动的方法。通过分析预报误差检测轨道参数的异常编目值,进而获得相应的历史机动信息。对卫星的两行轨道要素编目数据两两预报求差得到预报误差的样本数据后,利用期望最大化算法可以拟合得到以高斯混合模型表达的预报误差的概率分布模型;以此为基础,可以确定利用预报误差检测轨道参数异常编目值的门限;利用轨道机动与异常编目值之间的对应关系,最终实现机动检测。对典型活动卫星的机动检测结果表明,所提方法能够在准确检出历史机动事件的同时保持较低的误检率。

Orbit maneuvers can cause satellite orbital anomalies and are one of the key concerns of the space situational awareness.A method to detect historical orbital maneuvers from satellite TLE(two line element)data was proposed.By analyzing the prediction errors,the abnormal cataloging values of the selected orbital parameter were detected,and then the corresponding historical maneuvering information was obtained.Firstly,a large number of sample data of prediction errors were obtained from the historical TLE data,and the probability distribution model of the prediction errors expressed by the Gaussian mixture model was fitted from these sample data by the EM(expectation maximization)algorithm.Then,based on the fitted distribution model,the threshold of detecting abnormal cataloging values of orbital parameter through prediction errors was determined.Finally,taking into account the relationship between orbital maneuvers and abnormal cataloging values of the orbital parameter,the method to detect orbital maneuver from the cataloging sequence of the orbital parameter was determined.The results of maneuver detection on typical active satellites show that the proposed method can detect historical maneuvers accurately while maintaining a low false detection rate.