空间目标视星等曲线仿真

人类航天活动日益频繁，空间目标种类和数量不断增多，识别未知空间目标的关键特征具有重要的科学价值。本文通过辅助图形软件建模分割，获取球体、圆锥体和圆柱体带法向量的面元坐标；基于卫星仿真工具包，得到了目标轨道及位置参数，并结合双向反射分布函数各向异性Phong 模型和四元数姿态更新模型，完成了地基观测条件下4种形状空间目标的视星等仿真。仿真结果表明，目标受空间位置、形状和姿态的影响程度不同，其光度曲线具有各自特点。球体由于形状完全中心对称，光度曲线主要受空间位置的影响；圆锥体、正方体、圆柱体光度曲线的波形受形状影响较大，曲线走向受位置影响较大，波动频率受姿态角速率影响较大。通过统计分析相关数据，可为后续空间目标位置、姿态和形状的反演提供先验模型。 

Simulation of Apparent Magnitude Curves of Space Objects

With the increasing frequency of human space activities and the increasing variety and number of space targets, it is of great scientific value to identify the key features of unknown space targets. By segmentation using auxiliary graphics software, the surface coordinates of sphere, cone and cylinder with a normal vector are built. Based on the satellite simulation toolkit, the target orbit and position parameters are obtained. Combining with isotropic Phong BRDF model and attitude quaternion update model, the apparent magnitudes of these four shape space targets under ground observation conditions are simulated. Simulation results show that the target is affected by the spatial position, shape and attitude in different degrees, and each light curve has its own characteristics. Because the sphere is completely centrosymmetric, the light curve is mainly affected by the space position. Light curve waveforms of the cone, cube and cylinder are mainly influenced by shape, the curve trends are mainly influenced by position, and wave frequencies are mainly influenced by attitude angular rate. By statistical analysis of the data, a prior model can be provided for the subsequent inversion of space target position, attitude and shape.