Design And Brodband Researh Of Polarization Converter Based On Metamaterial

Polarization is one of the most important characteristics of electromagnetic wave.For the control of various polarization states,it needs the help of polarization converter.Polarization converters have important application value in satellite communication,electromagnetic stealth,antenna design,imaging and beam control.The traditional polarization converter mainly uses the materials existing in nature,and controls the polarization state depending on the birefringence effect and circular dichroism of the materials itself.However,this often requires massive volume to achieve sufficient phase accumulation in the direction of propagation.The emergence of metamaterials provides a new direction for the development of polarization converters.Based on the design idea of metamaterials,thesis studies the polarization converter.The main contents are as follows:First,thesis presents a triple-band polarization converter based on double seal,which has a relatively wide bandwidth.The modeling process of the polarization converter is introduced in detail by using CST software.Then,the performance of the polarization converter is studied under the incident of the linear and the circular polarization waves.The simulation results show that the triple-band polarization converter can realize efficient polarization conversion of the linearly and circularly polarized waves in the range of 8.31 GHz-12.67 GHz,18.09 GHz-20.63 GHz and 25.02 GHz-26.34 GHz.And the above phenomena are analyzed theoretically.Second,we design a broadband polarization converter which can work in C-and X-band.The polarization converter has the advantages of simple structure,high conversion efficiency and wide bandwidth.The structural parameters are analyzed and the principle is explained.It is found that the polarization converter can maintain good performance over a wide range of angles.Finally,the ability of the broadband polarization converter is further verified through experiments,and it has the potential of practical application.