宽带Fabry-Perot谐振腔天线及可重构技术在其中的应用

发布时间：2017-12-27 07:27

本文关键词：宽带Fabry-Perot谐振腔天线及可重构技术在其中的应用　出处：《西安电子科技大学》2016年博士论文　论文类型：学位论文

【摘要】：Fabry-Perot干涉仪于1899年由C.Fabry和A.Perot共同发明。它利用多光束干涉原理产生了半宽度很小的细锐条纹,具有极高的色分辨本领,能够精确地测量和控制光的频率和波长,因此被广泛地应用在光通信和光谱学领域。Fabry-Perot干涉仪的特性是当入射光的频率满足共振条件,其透射频谱会出现很高的峰值,对应着很高的透射率。随着激光技术的进一步发展,Fabry-Perot干涉仪有了新的表现形式——Fabry-Perot谐振腔,并且它也成为激光器的重要组成部分。Fabry-Perot谐振腔天线由于具有低剖面、高增益、馈电结构简单等优点,成功地替代了传统的高增益天线,成为近些年微波与毫米波天线领域的研究热点。Fabry-Perot谐振腔天线通常基于频率选择表面,通过在馈源天线上方的适当位置放置一个具有部分反射特性的反射覆层,使之与天线地板形成一个谐振腔结构。Fabry-Perot谐振腔天线克服了传统微带贴片天线增益低、效率低等缺点,无需通过构建阵列天线或加载复杂的馈电网络即可显著地提高天线的增益。但由于频率选择表面以及谐振腔自身的结构都具有窄带特性,因此Fabry-Perot谐振腔天线的阻抗带宽和增益带宽通常都比较窄,这在一定程度上限制了它在一些领域的应用。如果能够拓展这类天线的阻抗和增益带宽,将给其提供更为广阔的应用前景。另一方面,由于可重构天线具有功能多样性的特点,不仅能满足当代通讯信道多变,高速率的要求,又能极大地降低通讯平台上天线的数量,简化电磁环境,因此这类天线具有很重要的应用价值。为了使天线同时满足高增益和多功能的通信需求,可重构概念也被引入Fabry-Perot谐振腔天线的设计当中。然而,由于天线的频率特性和辐射特性是相互影响,紧密相联的。在对天线的某一特性实现重构的同时,往往会对天线的其它性能造成影响。此外,如何设计结构简单并且对天线性能影响较小的直流偏置电路也是实现可重构天线过程中的难点。基于此研究背景,本文以宽带Fabry-Perot谐振腔天线和可重构Fabry-Perot谐振腔天线为主要研究对象,首先介绍了Fabry-Perot谐振腔天线的基本概念,并基于四种模型介绍并分析了Fabry-Perot谐振腔天线的工作原理,总结归纳了谐振腔天线实现宽带和实现可重构的方法,并根据以上理论和方法对Fabry-Perot谐振腔天线的宽频带技术和可重构技术进行了深入的研究和探讨,最终提出、加工并测试了多种新型Fabry-Perot谐振腔天线,有效地解决了该天线领域中存在的一些关键技术问题。具体来讲,本文的主要贡献可以概括为以下四个部分:1、作者提出了一种拓展Fabry-Perot谐振腔天线增益带宽的新方法——在传统的地板上加载金属楔形结构。这种方法通过改善谐振腔的内部结构,降低谐振腔的品质因数,补偿了电磁波因反射路径不同引起的相位差。基于以上理论分析,提出了一种新型宽带Fabry-Perot谐振腔天线,并对其进行了仿真和实测,结果表明该天线可以在不影响其他性能(阻抗匹配、最高增益、辐射方向图等)的同时显著地提高谐振腔天线的增益带宽。最终设计天线的实测3dB增益带宽为20.8%。2、作者分析了三种具有正相位梯度特性的反射覆层单元。通过对其反射性能的比较,最终将一种具有双层双面印制正方形环结构的反射覆层单元运用在可以实现宽带性能的Fabry-Perot谐振腔天线设计中,并给出了不同的结构参数对该反射覆层电磁特性的影响。结果表明,该天线也可以在不改变天线的阻抗匹配特性的同时,显著地提高谐振腔的增益(17.4dBi)和增益带宽(17.3%)。3、作者结合改变馈电结构和改变反射覆层的反射相位这两种方法,提出了一种以相控阵天线作为馈源,可以实现离散波束扫描的方向图可重构Fabry-Perot谐振腔天线。通过加载基于可重构缺陷微带结构的馈电网络,谐振腔天线的波束可以在-10°,0°,10°的角度范围内进行调节。在此基础上引入可重构反射覆层结构,通过控制反射覆层上开关二极管的状态,该天线的波束可以在±15?的范围内进行调节。相比其他文献中提及的方向图可重构Fabry-Perot谐振腔天线,该设计馈电结构简单,不需引入其他阻抗匹配网络,并且波束调节的范围也更宽。4、作者提出了一种新型可重构馈电网络,并将该网络应用在短路环天线中,以此天线作为馈源激励Fabry-Perot谐振腔,最终设计了一种具有宽带性能的极化可重构Fabry-Perot谐振腔天线。该天线最终可以在4.7GHz~5.36GHz(13.1%)的频带范围内实现线极化、左旋圆极化和右旋圆极化之间的切换。实验结果验证了以上的设计理论与方法。相较于其他极化可重构天线,该设计不仅具有宽带特性,同时还具有较高的增益,这些特点使其更适应现代无线通信系统的需要。
[Abstract]:The Fabry-Perot interferometer was co invented by C.Fabry and A.Perot in 1899. It uses the principle of multi beam interference to produce half width and small fine stripe. It has very high color resolving power. It can accurately measure and control the frequency and wavelength of light, so it is widely applied in the field of optical communication and spectroscopy. The characteristic of the Fabry-Perot interferometer is that when the frequency of the incident light satisfies the resonance condition, the transmission spectrum will have a very high peak value, which corresponds to a high transmittance. With the further development of laser technology, the Fabry-Perot interferometer has a new form -- Fabry-Perot resonator, and it has also become an important part of laser. Because of its advantages of low profile, high gain and simple feeding structure, Fabry-Perot resonant cavity successfully has replaced the traditional high gain antenna, and has become a research hotspot in recent years in the field of microwave and millimeter wave antenna. The Fabry-Perot cavity antenna is usually based on frequency selective surface, and a reflective cavity with partial reflection characteristics is placed at the appropriate position above the feed antenna, so that it can form a resonant cavity with the antenna floor. The Fabry-Perot cavity antenna overcomes the shortcomings of traditional microstrip patch antenna, such as low gain and low efficiency. It can significantly improve antenna gain without constructing array antenna or loading complex feed network. However, because the structure of the frequency selective surface and the cavity itself has narrowband characteristics, the impedance bandwidth and gain bandwidth of the Fabry-Perot cavity antenna are usually relatively narrow, which limits its application in some fields to a certain extent. If we can expand the impedance and gain bandwidth of this type of antenna, it will provide a wider application prospect. On the other hand, due to the versatile characteristics of reconfigurable antennas, it can not only meet the requirements of modern communication channels, but also greatly reduce the number of antennas on the communication platform and simplify the electromagnetic environment. Therefore, such antennas have very important application value. In order to make the antenna meet the high gain and multifunction communication requirements, the reconfigurable concept is also introduced into the design of the Fabry-Perot resonator antenna. However, the frequency and radiation characteristics of the antenna are closely related to each other. While one characteristic of the antenna is reconstructed, it often affects the other performance of the antenna. In addition, how to design a DC bias circuit with simple structure and less impact on the performance of the antenna is also a difficult problem in the process of reconfigurable antenna. Based on this research background, this paper based on broadband Fabry-Perot resonator antenna and reconfigurable Fabry-Perot resonator antenna as the main research object, first introduced the basic concept of Fabry-Perot resonator antenna, and four kinds of models based on introduction and analysis of the working principle of Fabry-Perot resonant cavity antenna, summed up the implementation of broadband antenna resonant cavity and implementation method reconstruction, and according to the above theory and method of broadband Fabry-Perot resonant cavity antenna technology and reconfigurable technology are deeply studied and discussed, finally put forward and tested a novel Fabry-Perot resonator antenna and processing, effectively solved some key technical problems in the field of the antenna. Specifically, the main contributions of this paper can be summarized into the following four parts: 1, the author proposed a new method to expand the gain bandwidth of the Fabry-Perot resonator antenna, which is to load the metal wedge structure on the traditional floor. This method through the internal structure to improve the resonant cavity, reducing the quality factor of resonant cavity, the electromagnetic wave reflection path compensation caused by different phase difference. Based on the above analysis, put forward a new kind of broadband Fabry-Perot resonator antenna, and has carried on the simulation and measurement, the results show that the antenna can not affect other properties (impedance matching, maximum gain and radiation pattern) and significantly improve the gain bandwidth of the resonant cavity antenna. The measured 3dB gain bandwidth of the final design antenna is 20.8%. 2. Three kinds of reflective coating units with positive phase gradient characteristics are analyzed. By comparing the reflectivity, will eventually have a double sided printed square ring structure reflecting coating unit application in the design of Fabry-Perot resonator antenna can achieve wideband performance, and the influence of different structural parameters on the reflection layer electromagnetic characteristics are given. The results show that the antenna can also significantly improve the gain (17.4dBi) and gain bandwidth (17.3%) of the resonator without changing the impedance matching characteristics of the antenna. 3, the author changed the reflection phase feeding structure and the change of antireflective coating of these two methods is presented using a phased array antenna as a feed, can realize the discrete beam scanning pattern reconfigurable Fabry-Perot resonator antenna. By loading a feed network based on the reconfigurable defect microstrip structure, the beam of the resonant cavity antenna can be adjusted in the angle range of -10, 0, and 10 degrees. On this basis, a reconfigurable reflector structure is introduced. By controlling the state of the switch diode on the reflector, the beam of the antenna can be adjusted within the range of + 15. Compared to other documents mentioned in the pattern reconfigurable Fabry-Perot resonator antenna, the design of the feed structure is simple and does not require the addition of any impedance matching network, and the wider beam adjusting range. 4, the authors propose a new reconfigurable feed network, and apply the network to the short circuited loop antenna. The antenna is used as a feed to stimulate the Fabry-Perot resonant cavity. Finally, a broadband reconfigurable Fabry-Perot resonant cavity antenna is designed. The antenna can eventually switch between the linear polarization, the left circular polarization and the right circular polarization in the range of 4.7GHz~5.36GHz (13.1%). experimental result
【学位授予单位】：西安电子科技大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TN820

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