综合函数矩量法在介质金属混合结构电磁散射特性分析中的应用研究

发布时间：2018-06-14 20:17

本文选题：表面积分方程 + 复杂媒质　；参考：《国防科学技术大学》2015年硕士论文

【摘要】：在计算电磁学领域,目标的电磁散射特性分析是一个重要的研究课题,特别是复杂媒质目标的电磁散射特性分析,一直是该领域的研究重点和难点。本文基于表面积分方程,分析了金属、均匀介质以及介质金属混合三种媒质类型周期性目标的电磁散射特性,分别利用了矩量法和综合函数矩量法作为求解手段。其中,综合函数矩量法是本文的研究重点,特别是针对介质金属混合结构的综合函数矩量法是本文的最大创新点。此外,矩量法作为一种成熟的经典算法,被本文用作综合函数矩量法的结果验证以及性能对比。本文主要工作可分为以下三个部分。第一部分中,介绍了与目标电磁散射分析相关的电磁理论,具体推导了金属、介质以及介质金属混合三类目标的表面积分方程。然后,基于EFIE,PMCHW方程以及EFIE—PMCHW方程,利用矩量法分别分析了这三类目标的电磁散射特性并推导了相关的矢量计算公式。第二部分中,首先介绍了综合函数矩量法的算法思想和基本原理。接下来具体介绍了利用综合函数矩量法分析目标电磁散射特性的操作方法,总结归纳出了综合函数的生成理论并给出了综合函数展开系数空间的生成方程。紧接着,通过具体的仿真算例,验证了算法有效性和准确性,并通过与矩量法对比,凸显了该算法在缩减计算内存方面的巨大优势,特别是在对于周期结构的分析中,计算效率提高明显。最后,根据综合函数矩量法的生成过程,探讨了截断误差和等效源的设置规则,分析了算法性能对于截断误差的敏感性,并为相关参数的设置提供了参考性意见。第三部分中,重点介绍了综合函数矩量法在“类周期”目标中的应用。通过理论分析和数值算例说明了综合函数的生成只与目标模块的几何形状有关。借此,提出了一些算法预处理过程,使得综合函数矩量法可以适用于旋转和缩放等“类周期”结构目标中。并进一步指出,只要待分析目标的不同模块之间的几何形状具有相似性,均可以利用综合函数矩量法进行求解,并不局限于周期的概念。最后,以一些具体的实验算例验证结束本文。通过暗室测量了一些典型微带贴片结构的空间RCS分布特性,并与综合函数矩量法的结果进行了对比,进一步验证了该算法的有效性。并且,针对丛林目标电磁散射特性分析实例,介绍了综合函数矩量法在实际问题中的应用,凸显了其实际应用价值。
[Abstract]:In the field of computational electromagnetics, the analysis of electromagnetic scattering characteristics of targets is an important research topic, especially the electromagnetic scattering characteristics of complex medium targets, which has always been the focus and difficulty in this field. In this paper, based on the surface integral equation, the electromagnetic scattering characteristics of periodic targets in metal, homogeneous medium and mixed medium are analyzed. The method of moment and the method of moment of synthesis function are used as the means to solve the problem, respectively. Among them, the method of moments of synthesis function is the focus of this paper, especially the method of moments of synthesis function for the mixed structure of dielectric metal is the most innovative point in this paper. In addition, as a mature classical algorithm, the method of moments is used in this paper to verify the results of the method of moments of synthetic functions and to compare its performance. The main work of this paper can be divided into the following three parts. In the first part, the electromagnetic theory related to the electromagnetic scattering analysis of the target is introduced, and the surface area fractional equations of metal, medium and dielectric metal mixture are derived in detail. Then, based on the EFIEE-PMCHW equation and EFIE-PMCHW equation, the electromagnetic scattering characteristics of these three kinds of targets are analyzed by the method of moments, and the relevant vector calculation formulas are derived. In the second part, the algorithm and basic principle of the method of moments are introduced. Then the paper introduces the operation method of analyzing the electromagnetic scattering characteristics of the target by using the method of moments, summarizes the generating theory of the synthesis function and gives the generating equation of the expansion coefficient space of the synthesis function. Then, the validity and accuracy of the algorithm are verified by a specific simulation example, and compared with the method of moments, it highlights the huge advantages of the algorithm in reducing the memory, especially in the analysis of the periodic structure. The calculation efficiency is improved obviously. Finally, according to the generation process of the method of moments of synthetic function, the setting rules of truncation error and equivalent source are discussed, the sensitivity of algorithm performance to truncation error is analyzed, and the reference advice is provided for the setting of relevant parameters. In the third part, the application of the method of moments of synthetic function in the object of "class period" is introduced. Theoretical analysis and numerical examples show that the generation of the synthesis function is only related to the geometric shape of the target module. In this paper, some preprocessing processes of the algorithm are proposed, so that the method of moments of synthetic functions can be applied to the "periodic" structure targets such as rotation and scaling. It is further pointed out that as long as the geometric shapes of different modules of the target to be analyzed are similar, they can be solved by using the method of moments of comprehensive functions, and not limited to the concept of periodicity. Finally, some specific experimental examples are given to verify the conclusion of this paper. The spatial RCS distribution characteristics of some typical microstrip patch structures are measured in the darkroom, and compared with the results of the method of moments of synthetic functions, which further verify the effectiveness of the proposed algorithm. Based on the analysis of electromagnetic scattering characteristics of jungle targets, this paper introduces the application of the method of moments of synthetic functions in practical problems, which highlights the practical application value of the method.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN011

【参考文献】