美国天基低轨红外系统中段目标探测方法分析

Analysis of Midcourse Target Detecting Method with SBIRS-Low

美国天基红外低轨系统在探测弹道中段目标时,大气辐射和背景星体辐射可能远大于目标辐射,探测存在一定的困难。根据天基红外低轨系统的设计要求,本文估计出一种天基多波段弹道中段目标探测方法。该方法根据星体辐射光谱容易获得这一特点,在大气辐射和目标辐射光谱未知的条件下,对正交子空间(OSP)算法进行改进。采用主成分分析方法,提取大气辐射背景主成分。再结合星体的端元信息,构成新的背景端元矩阵。并采用全一向量替代目标端元。计算机模拟表明该方法在有效地抑制大气和星体背景同时,可靠地探测出中段小目标。

When detecting ballistic midcourse target with the Space-based Infrared System-low（SBIRS-Low）,the background radiation of atmosphere or stellar is usually much stronger than that of target.Detection midcourse target is difficult.Based on design requirements of space-based infrared system-low,a method of detecting ballistic midcourse target with the space-based multi-band image system is inversed.In general,endmembers of target and atmosphere background are uncertain,and endmember of stellar radiation can been obtained by estimating the atmosphere absorbance.In this condition,a new algorithm based on OSP algorithm is proposed.Background endmembers matrix is made up of stellar endmember and atmosphere endmembers extracted with PCA method.Target endmembers is replaced with a unit vector.Computer simulations results show that the algorithm can effective suppress the background clutter of stellar and atmosphere.And midcourse target can been detected reliable.