卫星褶皱表面的光学散射特性

Optical Scattering Characteristics of Satellite with Fold Surface

卫星表面褶皱会对卫星的光学散射特性产生显著影响,进而影响光学设备对目标的探测,而关于卫星褶皱表面光学散射特性的研究大多将褶皱近似为漫反射材料,导致近似误差大且缺乏依据的问题。以卫星表面常用包覆材料银色聚酰亚胺薄膜为研究对象,借助三维(3D)建模技术实现对空间目标褶皱表面的模拟,通过计算不同入射角和观测角时目标的光学横截面积,定量研究了不同程度的褶皱对目标光学散射特性的影响。结果表明:褶皱使目标峰值散射变暗,但使探测器的可观测范围变大,由平整表面5°镜面反射角发散至褶皱表面约42°可观测反射角,对散射特性产生了巨大影响;在对卫星进行光学特性研究时,需结合卫星的加工情况对目标表面进行相应的褶皱处理,以提高分析精度。

The folds on the surface of a satellite have a significant effect on optical scattering properties of the satellite, thereby affect the detection of the satellite by using optical devices. As far as the optical scattering characteristics of the satellite fold surface are concerned, most previous studies treat the folds as diffuse reflection materials, which results in large approximation errors and lack of basis. Taking the silver coated polyimide film of the satellite as the research object, we adopt the three-dimensional （3D） modeling technology to simulate the space target fold surface. The effect of folds with different degrees on optical scattering characteristics of the target is quantitatively investigated by calculating the optical cross section （OCS） of the target with different incidence angles and observation angles. The results show that the folds make the scattering peak of the target lower, but make the observation range of the detector extended, which is from specular reflection angle of 5° of the flat surface to the observable reflection angle of about 42° of the fold surface. Thus a huge impact on the scattering characteristics is produced. In the study of optical properties of the satellite, the corresponding surface fold treatment of the space target should be implemented by considering processing situations of the satellite to improve the accuracy of the analysis.