材料非线性的表征及测试方法研究

发布时间：2018-02-09 14:33

本文关键词： 微波大功率材料非线性介电常数　出处：《电子科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,随着雷达、无线通信、遥感探测等技术的快速发展,微波成了现代社会中必不可少的组成部分。由于微波在实际应用中的功率和频率在不断提升,对于材料在微波大功率条件下的电磁性能的研究变得越发紧迫且重要。但是在微波大功率条件下材料的电磁特性往往会有别于直流和低频,而出现一些特殊的现象。目前,关于材料的电磁参数随微波功率变化的研究还非常少。这对于实际应用来说是远远不够的。所以本课题的目的便在于研究材料在微波大功率条件下的特殊现象。此项研究无论在微波领域还是材料领域都具有非常重要的理论和工程意义。材料的非线性是指,材料的电磁参数,如介电常数、损耗正切、磁导率等,随着微波功率或者频率的变化而产生变化的现象。本课题的主要研究材料电磁参数由于微波电场强度的变化而产生的非线性现象。为了完成本课题的研究。首先,以课题的研究内容为方向,了解并分析了课题相关的国内外的理论与测试技术的发展状况。其次,分析了在微波大功率条件下材料可能产生的非线性现象及其机理。并对一些材料的微观机理和特殊性质进行了解和分析。然后,利用矢量网络分析仪和功率放大器组建了高功率微波电场作用和测试实验系统,研制了TM0n0模高功率电场产生谐振系统。最后,选择一些微波大功率条件下的常用的材料,如石蜡、聚四氟乙烯、铁电体、惰性气体等进行实验。实验结果表明,铁电体材料的介电常数和损耗正切都会随着微波功率的变化而产生变化。惰性气体在微波强电场的作用下会被电离而成为等离子体。高损耗的电介质,在微波强电场的作用下会迅速吸收能量而升温,从而导致介电常数和损耗的变化。但是实验中的低损耗电介质材料在目前的实验功率和频率下,未观测出明显变化,不能得出具有非线性特性的结论。相关课题目前在国内报导极少,属开创性的探索工作,作者在该研究方向上作了起步性的研究。本课题的研究为进一步研究微波大功率条件下材料的非线性研究奠定了基础。作者希望通过本课题的研究使业界人士更加的关注材料电磁参数随微波功率的变化,以此来推动材料电磁学的发展。
[Abstract]:In recent years, with the rapid development of radar, wireless communication, remote sensing and other technologies, microwave has become an essential part of modern society. The study of the electromagnetic properties of materials under the condition of microwave power becomes more and more urgent and important. However, the electromagnetic characteristics of materials under the condition of microwave power are often different from those of DC and low frequency, and some special phenomena appear. There are few studies on the electromagnetic parameters of materials varying with microwave power, which is far from enough for practical applications. Therefore, the purpose of this paper is to study the special phenomena of materials under the condition of microwave power. This research is of great theoretical and engineering significance in both microwave and material fields. Electromagnetic parameters of materials, such as dielectric constant, loss tangent, permeability, etc. The main research of this subject is the nonlinear phenomenon caused by the change of the electromagnetic parameters of materials due to the change of the microwave electric field intensity. In order to complete the research of this subject, first of all, Taking the research content of the project as the direction, the development situation of the theory and test technology at home and abroad related to the subject is understood and analyzed. Secondly, In this paper, the possible nonlinear phenomena and mechanism of materials under microwave and high power conditions are analyzed, and the microscopic mechanism and special properties of some materials are analyzed. The experiment system of high power microwave electric field action and measurement is constructed by using vector network analyzer and power amplifier, and the resonant system of TM0n0 mode high power electric field is developed. Finally, some common materials under microwave and high power condition are selected. Such as paraffin, polytetrafluoroethylene, ferroelectrics, inert gases, etc. The experimental results show that, The dielectric constant and loss tangent of ferroelectric materials change with the change of microwave power. The inert gas is ionized into plasma under the strong electric field of microwave. Under the action of the strong electric field of microwave, the energy is absorbed rapidly and the temperature is heated, which leads to the change of dielectric constant and loss. However, the low loss dielectric material in the experiment does not show obvious change at the present experimental power and frequency. It is impossible to draw a conclusion with nonlinear characteristics. The related topics are rarely reported in China and are pioneering explorations. The author has made a preliminary study in this research direction. The research of this subject lays a foundation for further research on the nonlinearity of materials under the condition of microwave and high power. The author hopes that through the research of this subject, people in the industry will become more. The electromagnetic parameters of the added materials vary with microwave power, In order to promote the development of material electromagnetics.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN015

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