大视场龙伯透镜电磁成像超分辨算法

Large field-of-view Luneburg lens electromagnetic imaging super-resolution research

现有的反射面电磁成像系统体积庞大,无法满足机载、车载、无人机等应用平台要求。针对此类问题,研究了龙伯透镜的结构特性和成像特性,设计了大视场龙伯透镜电磁成像系统,利用空不变成像特性进行超分辨图像处理,实现了快速、大视场、宽频带、高分辨电磁辐射源分布成像。计算了口径300 mm带球核分层龙伯透镜参数,仿真了4~18 GHz龙伯透镜焦弧面场强分布,验证了龙伯透镜空不变的成像特性及其超分辨算法的有效性。实验对比了抛物反射面电磁成像系统和本文龙伯透镜电磁成像系统的体积、成像范围、源数目和分辨率,结果证明了本文系统的优越性,同样分辨率下,达到了方位角及俯仰角均为40°的大视场范围。

Due to extensive electromagnetic radiation or interference,the rapid detection and location of electromagnetic interference sources in a large space has become a hot issue to be studied urgently.Electromagnetic imaging technology can visually display the location of radiation sources and solve the problem of rapid detection and localization of electromagnetic interference sources.However,the existing reflector electromagnetic imaging system is bulky and cannot meet the requirements of airborne,vehicle-mounted,UAV and other application platforms.To address this issue,this paper studies the structure and imaging characteristics of Luneburg lens,designs a large field-of-view Luneburg lens electromagnetic imaging(EMI)system,and realizes rapid identification and location of EMI with the advantages of large field of view,wide bandwidth and high resolution.In this paper,the parameters of the 300 mm Luneburg lens with spherical core are calculated,the E-field intensity distribution of the 4~18GHz is simulated,and the space invariant imaging characteristics of Luneburg lens and its super-resolution algorithm are verified.The paper finally compares the volume,field of view,source number and resolution of the parabolic reflector electromagnetic imaging system and the Luneburg lens electromagnetic imaging system.The results demonstrate the superiority of the system proposed in this paper,achieving a large field of view with azimuth and elevation angles of 40°at the same resolution.