Design Of Ka Band Dual Circularly Polarized Antenna And Its Application In LEO Satellite Communication

In order to improve the satellite data transmission rate and relieve the shortage of spectrum resources,this paper presents a design scheme of Ka band dual circular polarization antenna.Firstly,this paper introduces the research background of LEO satellite communication,such as working frequency,antenna technology,constellation networking and so on.Secondly,this paper analyzes the application of LEO satellite in the emerging fields such as satellite to ground 5G fusion,and puts forward some ideas and suggestions for the application of Ka band LEO satellite communication system in the field of emergency communication based on the author’s actual work and research.Thirdly,the polarization theory,circular polarization technology and important performance parameters of the antenna are analyzed,and the antenna design scheme is given.Finally,a Ka Band Dual circularly polarized antenna is designed and verified according to the antenna specifications.The input port of the antenna is a standard waveguide,Transition to broadband diaphragm polarizer and square waveguide body through a section of turning structure,The back end of the waveguide is connected with the horn antenna to radiate the signal.In this paper,the basic principle of realizing double circular polarization of antenna is analyzed.By using CST software and a lot of simulation optimization,the optimal structure is determined.The simulation results show that in the working-band(23%),the VSWR is lower than 1.3,the isolation between the two input port is lower than-20 d B,gain is larger than 14.7 d B,the axial ratio is lower than 3d B,the simulation results are good and meet the requirements.Finally,the antenna was been measured.The VSWR of the antenna was been measured by vector network analyzer,spectrum analyzer and other instruments.The antenna pattern was been measured in the microwave anechoic chamber,and the measurement results meet the requirements.