大气流场传输效应对探测系统性能的影响

分析了目标与背景的红外辐射特性,建立了目标与背景辐射温差传递数学模型,研究了大气对红外辐射传输的影响,分别考察了水蒸气、二氧化碳的吸收和大气散射对红外辐射传输的影响;计算了探测系统的主要性能评价参数:调制传递函数、最小可分辨温差和视距,并通过仿真得到了探测系统对目标所成的失真目标图像。研究结果表明,大气流场传输效应会使得探测系统对目标的成像发生像模糊,导致目标与背景之间的对比度下降。

Influence of Atmospheric Transmission Effect on Characteristics of Detection System

The infrared radiation features of targets and background are analyzed. A mathematic model of radiant temperature difference transmission of a target and its background is established. The influence of atmosphere on infrared radiation transmission is studied. The influences of water vapor absorption, carbon dioxide absorption and atmospheric scattering on infrared radiation transmission are investigated respectively. The main performance evaluation parameters of a detection system, such as modulation transfer function, minimum resolvable temperature difference and visual range, are calculated. Through simulation, a distorted target image formed by the detection system is obtained. The research result shows that the atmospheric transmission effect can make the target image formed by the detection system to be blurred and cause the contrast between the target and the background to be decreased.