空间目标红外成像特性建模与仿真

基于空间目标成像特性的几何模型,引入了区域分解、网格划分的思想,利用双向反射分布函数建立了空间目标红外光谱特性与成像特性的数学模型,给出了目标在探测器入瞳处及像面上的能量分布计算公式。基于目标和探测器的轨道参数,分析了空间目标的成像条件,给出了成像角度和成像尺度判断的数学依据。以风云一号卫星和伽利略卫星为例,根据目标的结构特性、材料特性、轨道特性等确定输入条件,计算获得了目标在探测器入瞳处的辐射照度及目标红外星等随时间的变化关系,同时获得了目标灰度图像随时间的变化特征。仿真结果验证了建模方法的正确性,实现了空间目标红外成像特性的动态模拟。

Modeling and simulation on infrared imaging characteristics of space target

Modeling method of infrared imaging characteristics of space target was proposed.Based on the geometrical model of imaging characteristics,mathematical models of spectral and imaging characteristics of space target were established with bidirectional reflectance distribution function(BRDF) by introducing region and grid division.Calculation formulas of target irradiance on entrance pupil and image plane of detector were derived.Imaging condition of space target was analyzed in accordance with the orbital parameters of target and detector,and mathematical basis of imaging angle and scale was given.Taking the properties of structure,material and orbit as the input parameters,variation features of pupil irradiance,infrared magnitude and gray image of FY-1 and Galileo satellites were demonstrated.The calculation results verify the validity of modeling method.The dynamic simulation of infrared imaging characteristics of space target is achieved.