典型大气条件下目力光学侦察效能分析

Effectiveness analysis on eyeballing optical reconnaissance under a typical atmospheric condition

目力光学侦察的效能评估的关键是对发现概率或作用距离进行定量计算。影响发现概率的因素主要有:大气能见度、目标与背景对比度、目标的大小与距离以及目标所处的天顶角位置等。利用通用大气辐射传输软件CART可以综合考虑这些因素的影响,在建立的目力光学探测模型的基础上,计算了典型大气条件下目力光学侦察对目标的发现概率与识别概率随距离的变化关系;计算了在不同能见度下、不同天顶角时目力光学侦察对典型目标的作用距离。计算表明:在一段很近的距离内,目力光学侦察对目标的发现概率很高,随着目标距离的增加,发现概率迅速下降;目力光学侦察对目标的作用距离一般随着目标天顶角的增加而减小;能见度对目力光学侦察的距离影响非常大,但在能见度极低时,目力光学侦察距离几乎不随天顶角变化,计算结果对定量评估光学系统的侦察效能有借鉴意义。

The key for effectiveness evaluation of eyeballing optical reconnaissance is to calculate detecting probability or operating range.Detecting probability is determined by many factors,such as atmospheric visibility,target-background contrast,target size and distance,zenith position etc.These factors were all considered with the help of combined atmospheric radiative transfer（CART） software.After setting the detecting model of eyeballing optical system,the relation between detecting（recognition） probability and target distance was obtained under a typical atmospheric condition.Operating range for typical targets were quantitatively calculated under different visibilities and different zeniths.The conclusion shows that detecting probability is strong and steady when the target distance is less than the threshold.Once the distance is more than the threshold,detecting probability decreases quickly as the target goes away.The greater the zenith parameter,the shorter the operating range is.The visibility is very important to operating range.However,operating range almost keeps steady when visibility is very low.These conclusions are helpful for the reconnaissance effectiveness evaluation of optical systems.