Implementation Of Ferromagnetic Resonance Linewidth And Of Microwave Ferrite Materials

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.