Research On The Measurement Method Of Space Scattering Parameters Of Periodic Electromagnetic Structures

With the continuous development of microwave technology,various new electromagnetic materials have sprung up.The production and research of materials are closely related to electromagnetic parameters,and the difference in electromagnetic parameters fundamentally determines the different characteristics of materials.Therefore,while the combination and development of material science and microwave technology brings convenience to people,the study of electromagnetic parameters of microwave materials plays a very important role in scientific theory and engineering practice.Based on the research needs of electromagnetic parameters of microwave materials,it is very important to build a test system for electromagnetic parameters of microwave materials.Based on the theoretical basis of the network parameter method,this article proposes two test methods: free space method and the parallel plate waveguide method to meet the needs of wide frequency band and wide application.The specific research contents is as follows:(1)A free-space method test system for broadband measurement of electromagnetic parameters has been designed and built.According to the research on the measurement principle of the free space method,combined with the vector network analyzer,a free space method test system for broadband measurement of electromagnetic parameters has been built,which meets the requirements of measuring electromagnetic parameters in the range of 2 to 15 GHz.To verify the validity of the free space method test system,the existing periodic electromagnetic structure was tested.The test results show that the built free space method test system can measure the electromagnetic parameters of periodic electromagnetic structures,and has the advantages of broadband measurement,high precision,simple test,and non-contact and non-destructive properties.(2)A parallel-plate waveguide test system for broadband measurement of electromagnetic parameters was designed and built.According to the theory of parallel-plate waveguide and the measurement principle of transmission/reflection method,a parallel-plate waveguide test system for broadband measurement of electromagnetic parameters has been built,which meets the requirements of measuring electromagnetic parameters in the range of 1-10 GHz.In order to verify the effectiveness of the parallel-plate waveguide test system,a periodic electromagnetic structure was designed and tested.The test results show that the parallel plate test system can be used to test the electromagnetic parameters of the periodic electromagnetic structure.(3)The dielectric constant measurement of materials is investigated using parallel-plate waveguides.First,provide corresponding answers to questions that may arise during the testing process.Then,combined with the parallel plate test system,the existing dielectric plate is tested to obtain the scattering coefficient,and the electromagnetic parameters are reversed.The inverse results show that in the 4-8 GHz operating frequency band,the dielectric constant of microwave electromagnetic materials can be measured by using the parallel-plate waveguide,with a maximum measurement error of 8% and a measurement bandwidth of 68%.(4)An adaptive intelligent software is designed by using a high-level programming language combined with MATLAB.According to the design theory of software,adaptive intelligent application software is designed.The software mainly includes a data reading module,data processing module,image generation module,etc.Finally,the running result of the software is shown.The running results show that the designed adaptive and intelligent software can meet the function of measuring electromagnetic parameters with the designed test system.