金属目标对贝塞尔涡旋波束的近场电磁散射特性  

Near-field electromagnetic scattering of Bessel vortex beam by metal target

作　　者：陈鑫淼 李海英[1] 吴涛 孟祥帅 黎凤霞 Chen Xin-Miao;Li Hai-Ying;Wu Tao;Meng Xiang-Shuai;Li Feng-Xia(Institute of Physics,Xidian University,Xi’an 710071,China;Xi’an Institute of Space Radio Technology,Xi’an 710000,China;School of Information and Communication Engineering,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安电子科技大学物理学院,西安710071 [2]西安空间无线电技术研究所,西安710000 [3]西安交通大学信息与通信工程学院,西安710049

出　　处：《物理学报》2023年第10期54-64,共11页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:62171355,62101426,62201415);军委科技委基础加强计划技术领域基金(批准号:2021-JCJQ-JJ-1009);高等学校学科创新引智计划(批准号:B17035);陕西省自然科学基础研究计划(批准号:2021JM-135)资助的课题

摘　　要：相较于平面波,贝塞尔涡旋波束作为典型的涡旋波束,以其携带轨道角动量(orbital angular momentum,OAM)、无衍射、自重建的特性,使其在雷达检测、目标识别与成像等领域具有更加显著的竞争力.本文根据物理光学法和三角形面片建模,并结合贝塞尔涡旋波束的角谱展开法,导出了贝塞尔涡旋波束入射到任意金属目标的散射近场表达式,通过与FEKO软件仿真结果对比验证了本文方法的正确性.数值计算了简单和组合目标的散射近场的幅相和OAM分布以及雷达散射截面(radar cross section,RCS),分析了波束参数、接收面的距离和目标偏移波束距离等因素的影响.结果表明贝塞尔涡旋波束照射下的目标的近场幅相和OAM扰动与多种因素相关,这为进一步利用近场散射特征获得更多的目标信息奠定了基础.Bessel vortex beam,as a typical vortex beam,has the characteristics of carrying orbital angular momentum(OAM),no diffraction,and self-reconstruction,which makes it more competitive than plane wave in the field of future vortex beam target detection and imaging.In order to study the near-field electromagnetic scattering of a vortex beam by a metal target,the expression of the near-scattering field of Bessel vortex beam incident on any metal target is obtained by using the physical optics method,triangular surface element modeling,and the plane wave angular spectrum expansion method of vector Bessel vortex beam.The correctness of the proposed method is verified by comparing with the simulation results of FEKO software.The amplitude distribution and phase distribution of electric field,the OAM spectrum distribution and radar cross section(RCS)of the near-scattering field of the Bessel vortex beam incident on the simple target and the combined target are calculated.The effects of beam parameters,receiving distance,target shape and the positions of beam transmitting and receiving surfaces on near-field scattering results are numerically calculated.In addition,the distributions of near-field OAM spectra under different conditions and the near-field RCS distributions of different targets are given.The numerical results show that the near-field results of Bessel vortex beam incident on metal targets are related to the beam parameters,and conform to the law of Bessel beam changing with parameters.The near-field electric amplitude distribution is affected by the distance between the receiving surface and the target,but the phase distribution is hardly affected.The near-field scattering results reflect the changes of target shape.Under normal incidence,when the target is regular and symmetrical,the amplitude distribution and phase distribution are relatively regular,and the main mode is dominant.When the beam is obliquely incident on or does not fully illuminate the target,the amplitude distribution and phase distribution c

关 键 词：近场散射 角谱展开理论 涡旋波束 轨道角动量 

分 类 号：O441.4[理学—电磁学]