提出了一种空间目标红外动态辐射特性的建模方法。目标红外辐射包括自身发射辐射和对背景的反射辐射。根据目标与背景特征建立了空间目标辐射特性的物理模型。基于表面材料属性对目标表面进行区域与面元划分, 根据能量守恒定律, 利用目标在宇宙空间的热平衡方程建立了空间目标自身红外辐射特性的数学模型。同时, 引入双向反射分布函数模型描述目标表面面元的反射特性, 将目标所有面元反射分量叠加建立了目标红外反射特性的数学模型。最后, 构建目标本体坐标系, 通过坐标变换确定目标、背景辐射源与探测器的相对位置关系。根据给定的轨道参数、目标几何尺寸和表面物性参数仿真获得空间目标在轨红外特性。计算结果验证了模型的有效性, 为空间目标的红外探测与识别提供参考数据。

A modeling method of infrared dynamic radiation characteristics of the space target was presented. Infrared radiation of the target consists of self-emitted infrared radiation and reflected background infrared radiation. A physical model of radiation characteristics of the space target was established according to target and background characteristics. The target surface was divided into regions and grids based on material properties. According to thermal equilibrium equation of outer space target, a mathematical model on infrared radiation characteristics of the space target was presented based on conservation of energy principle. Bidirectional Reflection Distribution Function (BRDF) was introduced to describe infrared reflection characteristics of the target surface element, and a mathematical model on infrared reflection characteristics of the target was built by superimposing all the reflection components of surface elements. Finally, a body coordinate system was set and the relative positions of the target, the background radiation sources and the detector were determined in terms of coordinate conversion. Simulation of the target infrared characteristics in orbit was achieved according to its given orbital parameters, physical dimension and physical parameter of the target. The calculations show the model is valid and it can provide reference data to visible detection and recognition of space targets.