Research Of Satellite Communication Antenna In UHF And S Band

With the rapid development of science and technology,wireless communication has become an indispensable role in life.Among them,satellite communication antenna is widely used in communication service.In wireless communication system,antenna,as the part of transmitting and receiving electromagnetic wave,occupies an important position in the whole communication system.The performance of antenna directly determines the quality of the whole wireless communication system.Modern information technology has higher requirements for antenna performance.The antenna has a variety of forms,among which circular polarization antenna has more advantages than linear polarization antenna.For example,it can effectively suppress rain and fog interference,reduce multipath reflection,and reduce the effect of Faraday rotation effect.Therefore,circular polarization antenna is widely used in satellite communication,navigation and other fields.In this paper,the antenna of satellite communication in UHF and S band is studied.The main work is to combine the two antennas so that they can work well in both UHF and S bands.The main contents of the study are as follows:1.Research and design of the combined antenna in the UHF and S bands in the form of microstrip: The antenna radiates the right-handed circular polarization wave and left-handed circular polarization wave in two frequency bands,respectively.Firstly,the microstrip slot antenna in UHF band is designed.The antenna is fed by double H slot coupling and radiates electromagnetic waves outward through the patch above the slot.Two linear polarization waves with equal amplitude can be excited by the coupling feed of two H slots.Two H-slots are fed by Wilkinson power divider to produce two linear polarization waves with 90 degrees phase difference and finally form right-handed circular polarization waves.Secondly,the S-band antenna is designed: the antenna unit adopts a planar single-arm spiral antenna,and a metal disk is attached to the back of the spiral arm,which can adjust the input impedance of the antenna very well,and at the same time,reduce the height of the antenna.The antenna unit meets the performance requirements of the working frequency band well.In order to achieve the gain target,a 2 × 4 array antenna is used,which radiates left-handed circular polarization waves.In order to reduce the influence between the antennas of two different bands,the position of the antennas is adjusted so that the antennas in the two bands can meet the requirements in the frequency band.The antenna is processed and tested,and the test results are in good agreement with the simulation results.2.Research and design of the combined antenna in the UHF and S bands in the form of symmetric Dipole: The antenna radiates the right-handed circular polarization wave and left-handed circular polarization wave in two frequency bands,respectively.Both UHF and S band antenna elements use symmetrical dipole antennas,and two vertical currents can be generated by two orthogonal symmetrical dipole elements.In order to meet the condition of forming circular polarization,the elements of array antenna are fed by Wilkinson power divider to satisfy the phase difference of 90 degrees between the two antenna elements.In order to achieve the gain target,the UHF band antenna uses a binary array,S band antenna is 2 × 2 array.The feed network adopts the Wilkinson power divider.The S band antenna is placed in the UHF band antenna.Through the simulation of software HFSS,the simulation results meet the performance requirements.