Research And Design Of Broadband Multiband Vehicle Antenna

In recent years,the car has gradually become a new multimedia center in people’s life,and the new technologies related to the car,such as intelligent transportation and Internet of vehicles,have been promoted,which makes the vehicle communication system develop in the direction of broadband and multi band.Therefore,the antenna with wider frequency band and covering multiple communication frequency bands has become a research focus of automotive communication.Based on the electromagnetic dipole,this paper focuses on the antenna with broadband and multi band.The main research contents and achievements are as follows:1.Research on broadband and multi band dual polarization antenna based on electromagnetic dipole.By studying the radiation principle of the electromagnetic dipole and the current distribution of the antenna radiator,a broadband antenna with dual polarization characteristics is proposed,and an arrow shaped radiator is designed to improve the current distribution and achieve a more stable pattern.Secondly,the resonance characteristics of theΓ-shaped bending feed structure are analyzed,and the impedance bandwidth of the antenna is further broadened by using the series resonance introduced by the feeder.Based on broadband antenna,a laminated radiator structure is designed.By cutting off part of the current of the lower radiator and redesigning Γ-shaped feeder,the antenna presents multi band characteristics.Finally,through processing and testing,the broadband antenna reaches53% of the bandwidth,and the working frequency of the multi band antenna is 1.9GHz-2.6GHz and 5.4GHz-6.0GHz,both of which have good pattern characteristics of electromagnetic dipole antenna.2.Research on broadband circularly polarized antenna based on electromagnetic dipole.The antenna is based on the dual polarized electromagnetic dipole with broadband characteristics.By introducing a broadband feed network with phase shift function,the circular polarization characteristics are realized.Aiming at the problem of narrow beam width,the influence of radiators and reflectors on beam angle is further studied,and the beam width is effectively broadened by using downward bent radiators and inverted annular reflectors.Finally,after processing and testing,the impedance bandwidth and axial ratio bandwidth of the antenna are 73.6%,and the two vertical plane patterns of the antenna are consistent.The average 3d B axial ratio beam width is about 110° in the navigation frequency band,which meets the requirements of vehicle for satellite navigation and satellite communication.