弹道中段微动目标的回波中蕴含了目标的电磁特性和运动特性,为雷达目标识别提供了重要依据。本文研究了中段微动目标的宽带雷达回波模拟问题,提出了一种基于散射中心模型的回波模拟方法。通过对弹道中段目标的运动特性进行建模,分析了目标微动时各散射中心的位置变化规律,针对旋转对称体目标的外形特征,将目标的进动等效为二维平面内的转动,并基于物理光学法提出了一种计算散射中心遮挡效应的方法,解决了目标运动过程中姿态变化带来的遮挡问题。仿真实验与暗室测量数据的对比结果表明,所提方法可以有效模拟目标微动时各姿态的回波数据,为中段目标特征提取、目标识别提供了技术基础。
Radar echo of ballistic midcourse targets containing electromagnetic and motion information provides important evidence for target recognition.The problem of wideband radar echo simulation for micro-motion targets in ballistic midcourse is studied,and an echo simulation method based on the scattering center model is proposed in this paper.First,the position variation of each scattering center of circles of micro-motion targets is analyzed.Further,a method to judge the masking effect of scattering centers is proposed based on the physical optical principle by considering the structure of rotary symmetrical targets,under which the precession of the targets is equivalent to the rotation in a two-dimension plane.Therefore,the invisible problem of scattering centers arising from the variation of target attitude can be solved.Comparison between the numerical simulation and measurements in anechoic chamber indicates that the proposed method can effectively simulate radar echo of micro-motion targets,and provide a technical foundation for the feature extraction and recognition of midcourse targets.