预警卫星对弹道导弹航迹捕获算法

对弹道导弹目标捕获方法是空间预警系统的关键技术。该文通过对导弹推力加速度的分析，提出了目标在像平面的非线性运动模型。通过概率数据关联(PDA)求得等效的似然函数，利用Lagrange乘数法求得最佳的加权概率，使得对数似然比函数最大。结合量测的灰度信息，改善了其在低SNR情况下的检测性能。Monte-Carlo仿真验证了该方法的目标航迹检测性能和目标状态估计精度，仿真结果表明该方法在两方面都优于原有方法，适用于低SNR情况下预警卫星对弹道导弹目标捕获。

The Track Capture of Ballistic Missile from Satellite Observations

The target capture is the key technology of the space-based early warning system. In this paper,the thrust acceleration is analyzed,and then the nonlinear model of ballistic missile in the image is presented. Combined with the Probabilistic Data Association(PDA) ,the likelihood function is denoted,and the optimal weighted probability is calculated using Lagrange way which causes the logarithmic likelihood ratio maximum. Using the amplitude information of measurement,under low Signal-to-noise(SNR) the detection performance is improved. Via the Monte Carlo simulation,this method has the better detection performance and estimation accuracy than other approaches. It is applicable for the target capture under low SNR in the space-based early warning system.