【作者】 李林；

【导师】 郝永德；

【作者基本信息】 华中科技大学 ， 软件工程， 2017， 硕士

【摘要】 近年来,利用微波铁氧体材料成功研制出隔离器、电调滤波器、法拉第旋转器、环形器和相移器等微波器件。这些微波器件在雷达、电子对抗、人造卫星等方面得到广泛应用。而铁磁共振线宽,作为衡量这些器件的主要指标,其测试平台的标准化显得非常重要。现有的线宽测试系统主要有:能得到共振曲线但不能准确测量线宽值的传统教学仪器和精度高但价格昂贵的矢量网络分析仪构成的线宽测试系统,基于以上情况,研究出既用于实验教学又用于科研,性价比高的线宽测试系统具有重要意义。本论文结合铁磁共振线宽的国内外测试标准和测试系统制定的指标需求下,设计并实现一套既满足教学又满足科研的微波铁氧体材料线宽测试系统。在分析原理的基础上,推导了线宽的计算公式和线宽与磁损耗的关系。同时采用HFSS电磁仿真软件对线宽测试过程进行模拟,找出了吸收功率最大时的一半所对应的两个磁场值。本文采用自带方波调制幅度的微波源产生微波频率信号;采用精密衰减器间接地调节半功率点对应的两个直流磁场值;采用TE₁₀₆单模矩形谐振腔进行选频以及存储被测铁氧体小球发生铁磁共振前后的能量;采用检波器检波并通过示波器显示电压值,大大提高了测试系统的性价比。根据线宽测试流程,选取西南应用磁学研究所提供的微波铁氧体小球样品进行测试,得到的测试结果与样品的标称值对比并做相应的数据分析。实验结果对比可知,建立的测试系统达到相应的测试功能及系统测试技术指标。同时,本仪器通过分隔时间测量,获得的测量值相差很小,证明仪器的稳定性很好。系统模块化的构成,有利于学生对测试原理的理解,在实验教学方面有利于推广。更多还原

【Abstract】 In recent years,the use of microwave ferrite material successfully developed isolator,electric filter,Faraday rotator,circulator,phase shifter and other microwave devices.These microwave devices are widely used in radar,electronic countermeasures,artificial satellites and so on.And the ferromagnetic resonance linewidth,as a measure of the main indicators of these devices,the standardization of its test platform is very important.Existing line width test system mainly include: to get resonance curve but not accurate measuring line width values of the traditional teaching instruments and high precision but expensive line width testing system consisting of the vector network analyzer,based on the above situation,the research is used in the experiment teaching and for scientific research,cost-effective line width of the test system is of great significance.In this paper,based on the domestic and international standards of ferromagnetic resonance linewidth and the requirements of the test system,a set of measurement system for microwave ferrite material,which satisfies both teaching and scientific research,is designed and realized.On the basis of the analysis principle,the formula of linewidth and the relationship between linewidth and magnetic loss are deduced.At the same time,HFSS electromagnetic simulation software was used to simulate the linewidth measurement process,and two magnetic fields corresponding to half of the maximum absorbed power were found.In this paper,a microwave signal generator is used to emit microwaves with the amplitude of the square wave modulation microwave source,using precision attenuator to indirectly adjust the half-power point corresponding to the two DC magnetic field value,TE106 single-mode rectangular resonator is used to select the frequency and store the measured ferrite beads before and after ferromagnetic resonance energy and the use of detector detection and oscilloscope display voltage,all this greatly improving the test system cost-effective.According to the width of the test process,we select the Southwest Institute of Applied Magnetism provided by the microwave ferrite beads for testing samples,the obtained test results are compared with the nominal value of the sample and the corresponding data analysis is made.Comparison of the experimental results shows that the establishment of the test system to achieve the appropriate test function and system testing technical indicators.At the same time,the system through the separation time measurement,the measurement results are basically the same and the stability of the system is very good.The modularity of the system is conducive to the students’ understanding of the testing principle,which is conducive to the popularization of experimental teaching.更多还原