摘要
为避免将传统的频域方法直接用于复合模型瞬态场求解时面临计算量大的问题,运用时域有限差分(FDTD)方法计算了粗糙地面与下方同轴电缆复合电磁散射,其中,照射波选用平面微分高斯脉冲,粗糙土壤地面由Monte Carlo方法结合高斯功率谱密度来构建。通过FDTD近场迭代、近⁃远场外推、傅里叶变换、归一化散射截面计算得到了后向复合散射系数随入射波频率变化的曲线,分析了粗糙面几何统计参数、电缆参数、介质本构参数对散射系数的影响规律,获得了粗糙地面与下方同轴电缆较完整的宽带电磁散射特性,这些数值结果对粗糙背景下电缆的无损检测技术的发展具有重要意义。
In order to avoid the fact that the computation burden will be large when the traditional frequency domain method is used directly to solve the transient field problem of the composite model,the finite⁃difference time⁃domain(FDTD)method is used to calculate the composite electromagnetic scattering of the rough ground and the buried coaxial cables.The planar differential Gaussian pulse is chosen as the illuminating wave,and the rough soil surface is generated by means of the Monte Carlo method and in combination with Gaussian power spectral density.By the FDTD near field iteration,the near⁃to⁃far field transform,the Fourier transform and the computation of normalized radar cross section(NRCS),the curves of the composite backscattering coefficient in relation to the incident wave frequency are obtained.The influence of geometric statistical parameters of rough surface,cable parameters and dielectric constitutive parameters on scattering coefficient is analyzed.The relatively complete wide⁃band electromagnetic scattering characteristics of the rough ground and the buried coaxial cable are obtained.These numerical results are of great significance for the development of nondestructive examination technology of cables under rough background.
作者
王鹏飞
田炜
王玺
WANG Pengfei;TIAN Wei;WANG Xi(School of Physics and Electronic Information,Yan’an University,Yan’an 716000,China;Management Center for Solid Waste,Yulin Ecology and Environment Bureau,Yulin 719000,China)
出处
《现代电子技术》
2022年第23期161-165,共5页
Modern Electronics Technique
基金
榆林市科技计划项目(2015⁃02)。