基于超材料的频率可重构天线研究与设计

发布时间：2018-03-18 04:24

本文选题：频率可重构天线　切入点：超材料　出处：《电子科技大学》2016年硕士论文　论文类型：学位论文

【摘要】：随着电子和无线通信行业的快速发展,系统对设备的小型化、高增益、多频段等指标要求越来越高。天线作为系统接收信号和发射信号的部分,它的小型化至关重要。频率可重构天线通过改变其电气特性可完成多个天线的性能,从而减小通信系统的体积、提高系统的兼容性和降低成本。近几年来,超材料以其负介电常数、负磁导率、负折射率等独特的物理性质受到了极大的关注。已有不少研究者提出将超材料应用于天线中,解决一些传统天线设计无法解决的难题以达到天线小型化、多频带的目的。本论文主要研究超材料在频率可重构天线中的应用,通过改变超材料结构单元参数来改变天线的谐振模式从而实现频率的可重构,并利用超材料结构单元的色散特性验证这种方法的可行性。本论文主要内容及成果概括如下:首先,简要介绍了频率可重构天线和超材料的研究背景、国内外研究现状,而后分别介绍了超材料中左手传输线方程、复合左/右手传输线方程以及零阶谐振基本理论,最后简要介绍了天线和共面波导的相关理论。其次,设计了一款基于ENG-TL(Epsilon-Negative Transmission Line,负介电常数传输线)的频率可重构天线,该天线由两个ENG-TL单元构成,分别在两个单元与辐射贴片之间加载开关,通过开关的通断实现频率的可重构。该天线结构简单,性能稳定,可在三种工作模式之间切换,工作频率覆盖WLAN(2.4-2.484GHz)、WiMAX(3.3-3.69GHz)和C波段卫星通信的下行波段(3.7-4.2GHz)。最后,设计了两款基于CRLH-TL(Composite Right/Left-Handed Transmission Line,复合左/右手传输线)的小型频率可重构天线。这两款天线均有两个可重构模式,第一款为两个单频带模式,第二款为一个单频带模式一个双频带模式,可通过控制开关的通断方便的进行工作模式的切换。这两个天线尺寸仅为0.082λ×0.111λ×0.004λ(其中λ对应1.76GHz波长)。仿真和实测结果表明,天线在实现频率可重构的同时保持了稳定的辐射方向图,可用于WLAN(2.4-2.484GHz/5.725-5.825GHz)、WIMAX(2.5-2.69GHz)、ISM2.4GHz和UMTS(1750-1780MHz)系统。
[Abstract]:With the rapid development of the electronic and wireless communication industry, the system requires more and more equipment miniaturization, high gain and multi-frequency band. Antenna is the part of the system to receive and transmit signals. Its miniaturization is very important. The frequency reconfigurable antenna can accomplish the performance of multiple antennas by changing its electrical characteristics, thus reducing the volume of communication system, increasing the compatibility of the system and reducing the cost. Metamaterials have attracted great attention for their unique physical properties, such as negative permittivity, negative permeability and negative refractive index. Many researchers have proposed the application of metamaterials in antennas. In order to achieve the purpose of antenna miniaturization and multi-band, this paper mainly studies the application of metamaterials in frequency reconfigurable antenna, which can not be solved by traditional antenna design. By changing the parameters of the metamaterial structure element to change the resonant mode of the antenna, the frequency can be reconfigurable. The main contents and achievements of this paper are summarized as follows: firstly, the research background of frequency reconfigurable antenna and metamaterials is briefly introduced, and the current research situation at home and abroad is introduced. Then, the left-handed transmission line equation, the composite left-hand transmission line equation and the zero-order resonance theory in the supermaterial are introduced respectively. Finally, the related theories of antenna and coplanar waveguide are briefly introduced. A frequency reconfigurable antenna based on ENG-TL(Epsilon-Negative Transmission line (negative dielectric constant transmission line) is designed. The antenna consists of two ENG-TL elements, which load switches between the two elements and the radiation patch, respectively. The frequency can be reconfigurable by switching on and off of the switch. The antenna is simple in structure, stable in performance, and can be switched between the three operating modes. The operating frequency covers WLAN 2.4-2.484GHzn WiMAX 3.3-3.69 GHz) and the downlink band 3.7-4.2 GHz for C-band satellite communication. Finally, Two small frequency reconfigurable antennas based on CRLH-TL(Composite Right/Left-Handed Transmission line are designed. The second is a single-band mode and a dual-band mode, which can be switched easily by switching on and off of the control switch. The size of the two antennas is only 0.082 位脳 0.111 位脳 0.004 位 (where 位 corresponds to 1.76 GHz wavelength). The simulation and experimental results show that, The antenna can be used in WLAN 2.4-2.484GHz / 5.725-5.825GHz / s WIMAX 2.5-2.69GHz / ISM 2.4GHz and UMTS 1750-1780MHz systems.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TN820

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