海水包裹空心椭球体的低频散射场计算及分析  

Low-frequency scattering fields of a hollow ellipsoid enclosed by sea water

作　　者：徐龙飞 郑奎松[1] 张世田[2] 李亚静 XU Longfei;ZHENG Kuisong;ZHANG Shitian;LI Yajing(School of Electronics and Information,Northwestern Polytechnical University,Xi’an 710072,China;National key Laboratory of Electromagnetic Environment,China Research Institute of Radiowave Propagation, Qingdao 266107,China)

机构地区：[1]西北工业大学电子信息学院,西安710072 [2]中国电波传播研究所电波环境特性及模化技术重点实验室,青岛266107

出　　处：《电波科学学报》2018年第5期613-618,共6页Chinese Journal of Radio Science

基　　金：国家自然科学基金(61401361)

摘　　要：为了分析水下金属壳体目标的散射场,提出了一种基于移位算子时域有限差分方法的加速计算方法.利用该方法对海水、空气和金属三种媒质材料进行了建模,并计算了水下金属椭球状壳体目标低频散射场的空间分布和起伏海面对低频电磁波传播的影响.通过数值算例测试了所提方法的加速性能,可以得到接近线性的加速比和95%以上的加速效率.计算结果表明,海面会影响水下壳体目标散射场的空间分布,特别是对于电场的空间分布影响比较大,并且由于水下电导率的存在导致海面上方散射场的传播速度要比海面下方的快.In order to analyze the scattering fields of an underwater metal shell target,we propose a novel accelerating computation algorithm based on the shift operator finite difference time domain(FDTD)method for solving the case of a lossy dispersive medium.The spatial distribution of underwater low-frequency scattering fields of a hollow metal ellipsoid and the propagation properties of the low frequency electromagnetic wave across the rough sea surface are considered by the proposed method.For testing the acceleration performance,we obtain close linear speedup and get an acceleration efficiency of more than 95%through numerical cases.By calculating the radiation fields of an underwater electric dipole,it is shown that the results of the proposed method agree well with those analytic results.Numerical results show that the sea surface affects the spatial distribution of the scattering fields,especially the spatial distribution of electric field.Moreover,we get the propagating velocity of scattering fields which is faster above the sea surface than that below the sea surface.

关 键 词：色散介质 海面 低频 时域有限差分方法 电磁散射 

分 类 号：O451[理学—无线电物理]