并行FDTD方法在海面及其上方漂浮目标复合电磁散射中的应用  

Application of parallel FDTD to EM scattering from a target floating on sea surface

作　　者：贾春刚 郭立新[1,2] 刘伟[1] 尤立志[3] 

机构地区：[1]西安电子科技大学物理与光电工程学院,西安710071 [2]西安电子科技大学综合业务网理论及关键技术国家重点实验室,西安710071 [3]中航工业雷达与电子设备研究院航空电子系统射频综合仿真航空科技重点实验室,无锡214063

出　　处：《电波科学学报》2016年第1期116-122,共7页Chinese Journal of Radio Science

基　　金：国家杰出青年科学基金(61225002);航空科学基金与航空电子系统射频综合仿真航空科技重点实验室联合资助(20132081015)

摘　　要：利用基于图形处理器(Graphics Processing Unit,GPU)的并行时域有限差分(Finite Difference Time Domain,FDTD)法计算一维粗糙海面及其上方二维漂浮目标的复合电磁散射.采用各向异性完全匹配层(Uniaxial Perfectly Matched Layer,UPML)吸收边界作为截断边界,为了便于并行程序的设计,在整个计算区域使用UPML吸收边界差分公式进行迭代.利用异步通信技术来隐藏主机和设备之间的通信时间,同时使用片上的共享存储器提高读取速度,进一步对程序进行优化,得到很好的加速比,证明了该方法的计算高效性.通过与串行FDTD法以及串行矩量法获得的数值结果进行比较,验证了该并行方法的正确性,进而研究了海面上方类似舰船漂浮目标的电磁散射特性,讨论了入射角、海面风速以及目标吃水深度对双站散射系数的影响.In this paper,GPU-based FDTD algorithm is applied to study the electromagnetic（EM）scattering from two-dimensional（2-D）target floating on one-dimensional（1-D）rough sea surface with Pierson-Moskowitz（PM）spectrum.The FDTD lattices are truncated by uniaxial perfectly matched layer（UPML）,and the finite-difference equations are employed in the whole computation domain for the parallelization convenient to carry out.Also,the parallelism design is limited to the iteration of the near field that is extremely time consuming.To improve the performance,asynchronous transfers is implemented to mask the memory transfers time and the shared memory is used to achieve high memory bandwidth.Using compute unified device architecture（CUDA）technology,significant speedup ratios are achieved,which demonstrates the efficiency of GPU accelerated the FDTD method.The validation of our method is verified by comparing the numerical results with these obtained by sequential FDTD executing on CPU as well as method of moments（MOM）,which shows favorable agreements.Furthermore,our parallel implementation is employed to study the influences of the incident angle,the wind speed,the depth of the target on the EM scattering from the target and a sea surface composite model.

关 键 词：复合散射 海面 漂浮目标 FDTD GPU 

分 类 号：TN011[电子电信—物理电子学]