基于表面等离子体的透波增强特性及应用研究

发布时间：2019-01-29 19:51

【摘要】：透波增强现象自发现以来吸引了众多学者的关注。对透波增强现象的产生机理和应用潜力研究,在微波新型材料、微波性能调控以及新型微波器件设计等领域有着重要的意义。本文从表面等离子体理论出发,设计了金属-介质-金属三层透波增强结构,分析了该结构的透波机理。将透波增强现象应用在多频天线中,设计了一款新型双频高增益天线。本文的主要工作如下:(1)对透波增强特性和表面等离子体理论进行研究。研究发现:金属表面激发的传播型表面等离子体在低频时其色散曲线接近光在介质中的色散曲线,高频则趋近一条水平线,也就是传播型表面等离子体的共振频率;微小金属颗粒激发局域型表面等离子体,而典型的局域型表面等离子体具有横模和纵模两种模式。(2)为了研究表面等离子体对透射增强现象的影响,本文设计了金属-介质-金属三层透波增强结构。金属层分布周期性亚波长圆孔,在每个圆孔中添加金属圆柱来激发局域型表面等离子体。仿真结果表明,对比传统亚波长孔阵列结构,本文设计的三层结构出现了第二个透射峰,说明两类表面等离子体在透射增强现象中都有重要的作用。最后结合两类表面等离子体的特性研究了结构参数变化对透射特性的影响。(3)将透波增强现象应用在天线设计中,设计一种新型的双频高增益天线。在金属板中心开两个相交圆孔,圆孔周围分布环形凹槽,每个圆孔中心添加金属圆柱,使用标准矩形波导馈电。仿真结果表明天线的中心频率为11.9GHz和16.2GHz,增益分别为11.4dB和12.4dB,实物测试与仿真结果较吻合。该天线在天线设计和无线通信领域有较高的指导意义及应用价值。
[Abstract]:The phenomenon of wave penetration enhancement has attracted the attention of many scholars since it was discovered. It is of great significance to study the mechanism and application potential of wave-permeation enhancement in the fields of new microwave materials, microwave performance control and new microwave device design. Based on the surface plasma theory, a metal-dielectric metal three-layer wave-permeable structure is designed, and the mechanism of the structure is analyzed. A new dual frequency high gain antenna is designed by applying the phenomenon of wave transmission enhancement to the multi-frequency antenna. The main work of this paper is as follows: (1) the enhancement characteristics and surface plasma theory are studied. It is found that the dispersion curve of the propagating surface plasma excited by the metal surface is close to that of the light in the medium at low frequency, while the high frequency tends to a horizontal line, that is, the resonance frequency of the propagating surface plasma. Small metal particles excite local surface plasmas, while typical local surface plasmas have two modes: transverse mode and longitudinal mode. (2) in order to study the effect of surface plasma on transmission enhancement, In this paper, a three-layer structure of metal-dielectric-metal reinforced wave transmission is designed. The metal layer distributes periodic subwavelength circular holes, and the metal cylinder is added to each hole to excite the local surface plasma. The simulation results show that a second transmission peak appears in the three-layer structure compared with the traditional sub-wavelength aperture array structure, which indicates that both kinds of surface plasmas play an important role in the transmission enhancement phenomenon. Finally, the effects of structural parameters on transmission characteristics are studied by combining the characteristics of two kinds of surface plasmas. (3) A new dual-frequency high-gain antenna is designed by applying the phenomenon of enhanced wave transmission to antenna design. Two intersecting circular holes are opened in the center of the metal plate. Circular grooves are distributed around the circular holes. Metal cylinders are added to the center of each hole, and the standard rectangular waveguide is used to feed the holes. The simulation results show that the center frequency of the antenna is 11.9GHz and 16.2 GHz, and the gain is 11.4dB and 12.4dBrespectively. The results of the physical test are in good agreement with the simulation results. The antenna has high guiding significance and application value in the field of antenna design and wireless communication.
【学位授予单位】：安徽大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN820

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