应用天文研究组知识库

非合作目标的激光测距预报一般是基于双行根数(TLE)外推出来的,往往有较大偏差,对激光测距的成功率有较大影响。结合空间目标的轨道理论和实测的数据分析,预报的偏差主要是预测模型外推的空间目标在运行轨道上的平近点角与实际平近点角存在偏差。根据非合作目标在望远镜跟踪视场中的脱靶量,利用相关算法可以找到一个最佳的时间根数偏差量修正空间目标的平近点角。经过修正,空间目标的视位置偏差得到改善,距离偏差能够从几百米减小到几十米,提升了预期回波到达时刻的准确度,可以给单光子探测器提供更高精度的距离门控,提高测距成功率

Prediction for laser ranging of non-cooperative target is extrapolated from the Two Line Elements (TLE) normally, which has relatively large deviation and affects the success rate of laser ranging mission. Based on the orbital theory and the measured data of space target, the deviation of the forecast is mainly due to the deviation of mean anomaly from the prediction model and the real mean anomaly of the spatial target in the orbit. According to the target's miss distance in the field of view of tracking telescope, the relative algorithm can be used to find the optimal time element deviation to correct the mean anomaly of the spatial target. After modification, the visual position deviation of the space target is improved, the distance deviation can be reduced from several hundred meters to tens of meters, which makes the echo arrival time expectation more accurate, and can provide a more precise range gate control for the single-photon detector, and improves the mission success rate of laser ranging.