English

应用科学学报 ›› 1997, Vol. 15 ›› Issue (4): 394-401.

• 论文 • 上一篇    下一篇

半无限大空间中二维目标的探测

卿安永, 李敬, 任朗   

  1. 西南交通大学
  • 收稿日期:1996-07-29 修回日期:1996-11-01 出版日期:1997-12-31 发布日期:1997-12-31
  • 作者简介:卿安永:博士,西南交通大学电磁场与微波技术研究所,成都 610031
  • 基金资助:
    国家自然科学基金

DETECTION OF TWO-DIMENSIONAL OBJECTS IN HALF SPACE

QING ANYONG, LI JING, REN LANG   

  1. Institute of Electromagnetic Theory and Microwave Technology, Southwest Jiaotong University, Chengdu 610031
  • Received:1996-07-29 Revised:1996-11-01 Online:1997-12-31 Published:1997-12-31

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78

被引次数

3

摘要： 该文探讨利用时域散射场信息探测半无限大空间中二维目标.半无限大空间中目标的探测具有明显的实际应用价值,但相对自由空间而言,这种探测要困难得多,因而至今很少有人进行这方面的研究.该文给出一种基于体等效原理的探测半无限大空间中二维目标的方法,利用体等效原理,得到反映时域散射场和目标介电参数分布之间关系的体积分方程,经傅立叶变换并离散化后得到反演方程.这是一种选代方法,从一阶玻恩近似开始迭代,每次迭代过程中正问题和逆问题各计算一次,正问题采用FDTD方法.为了克服问题的病态,采用了伪求逆技术.文中用平面波展开法推导了半无限大空间中线源激励下的格林函数.文中列举了几个具有代表性的例子,最后讨论了有关的几个问题.

关键词: 时域有限差分, 伪求逆技术, 半无限大空间, 二维目标, 平面波展开

Abstract: The detection of shallow two-dimensional objects in layered media by using time domain scattering data is considered in this paper. A volumn integral equation which relates the scattering fields in time domain with the permittivity of the objects is obtained by volumn equivalence principle. The equation is transfered into frequency domain and the inversion equation is obtained after discretion. With our iterative method both forward and inverse problems are solved in each iteration. The forward problem is solved by using finite-difference time-domian method. The inverse problem is carried out by using a pseudoinverse technique. The Green function excited by line current source is derived by using plane wave expansion method. Several examples are given to show the ability of this metohd to invert arbitrarily shaped objects.

Key words: layered media, shallow two-dimensional objects, finite-difference time-doman, plane wave expansion method, pseudoinverse texhnique