多材质目标电磁散射仿真与成像特征分析方法研究

Research on Electromagnetic Scattering Simulation and Imaging Feature Analysis for Multi-material Targets

利用电磁计算方法对电大尺寸目标进行仿真成像是进行雷达目标特性分析的重要手段,多极化、多角度参数下获取的仿真图像可为雷达目标探测与识别提供大数据样本支撑。针对大巴车这种电大尺寸多材质目标的电磁成像仿真,提出了采用近景摄影测量技术来构建目标精细化几何三维模型和材质模型,基于射线寻迹几何光学(Ray-Launching Geometrical Optics, RL-GO)高频算法实现不同方位下的多材质目标雷达散射截面积(Radar Cross Section, RCS)计算和目标仿真成像,利用典型角度下的二维成像结果与目标三维几何模型之间的对应关系,进行散射中心位置的定量分析。实验结果表明了所提仿真方法的正确性,可实现对电大尺寸多材质目标进行精细成像仿真,并为雷达目标特性分析提供定量化解析依据。

Simulation imaging of electrically large targets using electromagnetic calculation method is an important way to analyze the features of targets in radar images.The simulation images obtained under multi-polarization and multi-angle parameters can provide a lot of data support for target detection and recognition.For the electromagnetic imaging simulation of electrically large size and multi-material targets such as buses,it is proposed to use close-range photogrammetry technology to build the refined geometric 3D model and material model of the target.Based on the high-frequency algorithm of Ray-Launching Geometrical Optics(RL-GO),the Radar Cross Section(RCS)calculation and target simulation imaging of the multi-material target in different directions are realized.The corresponding relationship between the two-dimensional imaging results at typical angles and the three-dimensional geometric model of the target is utilized to quantitatively analyze the scattering center position.The experimental results show that the simulation method proposed can realize the accurate simulation imaging of electrically large multi-material targets,and provide a quantitative basis for the analysis of radar target characteristics.