电磁超材料吸波结构的设计和应用

发布时间：2018-01-06 23:40

本文关键词：电磁超材料吸波结构的设计和应用　出处：《西安电子科技大学》2014年硕士论文　论文类型：学位论文

【摘要】：电磁超材料作为一种新兴的科研领域，自从1996年左手材料的实现至今，得到越来越多的重视。而作为电磁超材料的一个分支——电磁超材料吸波结构，因为其特殊的电磁波吸收特性，更使其得到学者们的广泛关注，从人体、仪器的电磁防护到武装单位的电磁隐身，，甚至是THz成像，都可以看到吸波材料的“身影”。本文首先介绍了电磁超材料以及吸波材料的概念，研究背景和意义。并详细阐述了吸波材料的演变过程和现阶段的科研进展，介绍了吸波材料的吸波机理。进而设计了一种以“耶路撒冷”吸波结构为基础衍生出来的新型超薄双频吸波结构——DSJ，该结构有着良好的吸波率，并且带有极化不敏感以及宽入射角度等特点，并采用了波导法对其进行测量。本文对DSJ进行了较为深入的分析，从表面电流、阻抗以及介质损耗三个方面递进式的阐述了吸波材料的吸波原理，并在此基础上，通过优化已有结构的极化特性，加之采用增加LC共振结构以及改变单元大小比例的方法，设计了另外两种新型多频带吸波材料，且均具有良好的吸波特性。其次，本文还对已有的宽频带材料进行了两种优化。一种是用氮化钽类电阻材质与复层吸波结构相结合，获得更薄的，吸波率曲线更平稳的吸波结构，且带宽保持不变。另一种是在原有的超宽频吸波材料的基础上，通过改变单元的对称性，以实现极化稳定的特点。证实了改变材质和单元形状对优化吸波材料的吸波特性存在可行性。最后，本文将DSJ运用到天线RCS减缩问题，结合缝隙耦合天线，实现天线在工作频带内电磁隐身的特性。表明了在电磁隐身方面有很好的应用前景。
[Abstract]:Electromagnetic metamaterials as a new research field, since the 1996 implementation of left-handed materials has attracted more and more attention. As a branch of electromagnetic metamaterials, electromagnetic metamaterials absorbing structure, because of the special electromagnetic wave absorption properties of the obtained widespread attention of scholars from the human body. Electromagnetic instrument electromagnetic protection to the armed units of stealth, even THz imaging, can see the absorbing material in the shadow.
In this paper, the concept, background and significance of electromagnetic metamaterials and microwave absorbing materials are introduced. The evolution process and research progress of microwave absorbing materials are introduced in detail. The absorbing mechanism of microwave absorbing materials is introduced.
To design a new ultra-thin dual band to "Jerusalem" absorbing structure derived based on wave absorbing structure -- DSJ, the structure has a good absorbing rate, and a polarization insensitive and wide incident angle and other characteristics, and the measurement of the waveguide method.
This article makes a deep analysis of DSJ from the surface current, impedance and dielectric loss of three aspects of progressive elaborated absorbing material principle, and on this basis, the polarization characteristics of the existing structure optimization, and the method to increase the LC resonance structure and change in proportion to the size of the unit, design the other two new multi band microwave absorbing material, and have good absorption characteristics.
Secondly, this paper on the existing broadband band material of two kinds of optimization. One is combined with multi layer absorbing structure with tantalum nitride resistor material, get thinner, the absorbing rate curve of absorbing structure is more stable, and the bandwidth remains unchanged. The other one is in the original ultra wideband absorbing materials on the basis of the symmetry change unit, in order to realize the characteristics of polarization stability. Confirmed the feasibility of changing the characteristics of absorbing material and absorbing material on the element shape optimization.
Finally, we apply DSJ to the RCS reduction problem of antenna, and combine the slot coupling antenna to realize the electromagnetic stealth characteristic of antenna in the working frequency band. It shows that it has a very good application prospect in the electromagnetic stealth aspect.

【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN820

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