新型人工电磁表面的理论、设计及系统级应用

发布时间：2018-06-04 20:29

本文选题：新型人工电磁表面 + 理论分析和建模　；参考：《东南大学》2016年博士论文

【摘要】：新型人工电磁表面是平面型新型人工电磁材料,是由亚波长结构单元按照特殊规律排列的周期或者准周期的二维表面结构。因其相对于三维新型人工电磁材料具有体积小、剖面低、损耗低、成本低以及易共形设计等优势,在近年来对电磁波的调控研究中发挥了巨大作用,从而成为电磁场相关学科的研究热点和焦点。本文详细研究了几种主流的新型人工电磁表面的理论建模方法,基于新型人工电磁表面设计了几类新型电磁器件,并给出新型电磁系统的设计理念。主要研究内容和贡献概括如下：1).基于各向同性新型人工电磁表面单元结构,提出了新型表面波无衍射Bessel透镜的设计方法,且在实验中得到验证。该设计方法利用组合透镜(半麦克斯韦鱼眼透镜加上平板透镜)的思想,可在点源激励下直接产生Bessel波束。2).基于各向同性新型人工电磁表面单元结构,提出了实现新型表面波傅里叶变换透镜的设计方法,且在实验中得到验证。对该透镜进行多馈点激励,可产生不同出射方向的表面平面波。3).将新型人工电磁表面与全息漏波天线原理相结合,分别利用全域和子域阻抗干涉图生成方法实现了新型多波束天线。其中基于全域干涉图生成方法所设计的双波束辐射会发生“兔子耳朵”现象,我们提出用侧馈的方式来解决这一问题,且在实验中得到了验证。结合漏波天线原理,本文给出了一维全息天线与漏波天线的等效性分析,并将其推广到二维。在国际上首次发现了仅用频率便可以控制波束二维空间扫描这一重大现象,并给出计算频扫二维波束角的经验计算公式。4).基于二维类表面等离激元(spoof spp)结构,结合全息天线原理,生成了螺旋式的全息干涉图,由于该新型人工电磁表面没有背面金属,因此可实现在表面正反两个方向分别辐射右旋和左旋圆极化电磁波。5).利用各向同性新型人工电磁表面结构单元设计了两个新型双功能器件：1)相同极化的双向辐射器；2)正交极化的同向辐射器。所设计的两款戏功能辐射器在不同极化激励下具有不同的频率扫描特性：对于水平极化,波束可以完成一维空间波束频率扫描；而对于垂直极化,波束则可以完成二维空间波束频率扫描。本文对第一款双功能器件进行了一维频率扫描特性的实验验证。6).基于表面波透镜和全息漏波天线的设计方法,提出了将两者结合起来实现低剖面天线系统的设计方案,即透镜可视为多端口馈电网络,而全息阻抗结构可作为辐射调制器。最后基于不同位置的馈电配合频率扫描实现了对二维空间进行波束覆盖的天线系统。仿真结果和近场天线的测试结果均证实了该天线系统理论设计的正确性。7).基于混合各向同性和各向异性的新型人工电磁表面单元结构,实现了双传感器“十”字形天线设计。该天线可实现在两个互相正交维度空间中波束的独立频率扫描。基于天线对远场目标的全覆盖照射,结合单雷达成像信号处理方法,实现了基于“十”字形天线的微波成像系统设计。在不同信噪比环境下对目标进行了图像仿真重构,获得了较好的图像分辨率,并证明该成像系统具有良好的抗噪性。
[Abstract]:A new type of artificial electromagnetic surface is a new type of plane type artificial electromagnetic material, which is a periodic or quasi periodic two-dimensional surface structure arranged by a sub wavelength structure unit according to special laws. The study of magnetic wave plays a great role in the research and control of the electromagnetic field. This paper has become the focus and focus of the research on electromagnetic fields. In this paper, the theoretical modeling methods of several mainstream electromagnetic surfaces are studied in detail. Based on the new type of artificial electromagnetic surface, several new types of electromagnetic devices are designed, and the design concept of the new electromagnetic system is given. The research contents and contributions are summarized as follows: 1. Based on the new type of isotropic artificial electromagnetic surface unit structure, a new design method of the new surface wave non diffracting Bessel lens is proposed and verified in the experiment. The design method can be used with the idea of combined lens (half Maxwell fish eye lens plus flat lens), which can be stimulated by point source. Bessel beam.2). Based on the new type of isotropic artificial electromagnetic surface unit structure, a new surface wave Fourier transform lens is designed and verified in the experiment. The surface plane wave.3 with different ejection direction can be generated by the multi feed point excitation of the lens. The principle of wave antenna is combined, and the new multi beam antenna is realized by using the whole domain and the subdomain impedance interferogram, in which the double beam radiation based on the whole domain interferogram generation method will take place "rabbit ears". We propose to use the side feed method to solve this problem, and it has been verified in the experiment. The principle of leaky wave antenna is presented in this paper. The equivalence analysis of one dimensional hologram antenna and leaky wave antenna is given, and it is extended to two-dimensional. In the world, it is the first time to find the important phenomenon that the beam two-dimensional space scanning can be controlled only by frequency, and the empirical formula.4 for calculating the two dimensional beam angle of the frequency sweep is given. Spoof spp structure, combined with the principle of holographic antenna, generates a spiral holographic interferogram. Because the new artificial electromagnetic surface has no back metal, it can radiate right-handed and left-handed circular polarization electromagnetic wave.5 in two directions, respectively. Two new kinds of new artificial electromagnetic surface structure units are designed. Dual function devices: 1) the same polarized two-way radiator; 2) the orthogonal polarization of the same direction radiator. The two play function radiators have different frequency scanning characteristics under different polarization excitation: for horizontal polarization, the beam can complete one dimensional space beam frequency scanning; and for vertical polarization, the beam can be completed. Two dimensional space beam frequency scanning. The first one is tested by the experiment of one dimension frequency scanning characteristic of the first dual function device. Based on the design method of the surface wave lens and the holographic leaky wave antenna, the design of the low profile antenna system is put forward by combining the two methods, that is, the lens can be seen as a multi port feed network, and the holographic hindrance is.6. The anti structure can be used as a radiation modulator. Finally, the antenna system that covers the two-dimensional space is realized based on the feed matching frequency scanning of different positions. The simulation results and the test results of the near field antenna confirm the correctness of the theoretical design of the antenna system. A new type of artificial electricity based on the mixed isotropy and anisotropy of.7). The magnetic surface unit structure is designed to design a dual sensor "ten" shape antenna. The antenna can realize the independent frequency scanning of the beam in two orthogonal dimensional space. Based on the full coverage of the antenna to the far field target, the microwave imaging system based on the "ten" shape antenna is realized with the single radar imaging signal processing method. The image simulation is reconstructed in different signal to noise ratio environment, and better image resolution is obtained. It is proved that the image system has good noise resistance.
【学位授予单位】：东南大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：O441;TN820

【相似文献】