Research On RF Design And Simulation For Mobile Terminal Of Internet Of Vehicle

Internet of Vehicle is a huge interactive network consisting of information of vehicle position,vehicle speed and vehicle route,which is the future development trend for vehicle and the inevitable requirement of information society.Internet of Vehicle cannot come true without the support of antenna technology,with the development of Internet of Vehicle,the quantity and type of vehicle antennas are increasing.Due to the increase of on-board electronic equipment,mounting space for vehicle antennas is decreasing,and in order to reduce windage coefficient of vehicle and keep the vehicle attractive,vehicle antenna is developing towards the trend of miniaturization and low profile.Microstrip antenna has the advantages of low profile,easy integration and simple feed structure,which can meet the trend of the development of vehicle antennas.According to the requirement of the miniaturization of the antenna mounted on vehicle,based on the theory of compound right-hand transmission line,this paper designs a miniaturized microstrip antenna which can be applied to the mobile terminal by using the meander line technology and the loading technology.The research content of this paper is divided into the following two parts:(1)The realization of miniaturization technology for microstrip antennas has been studied.To solve the problem that the antenna size and actual performance are difficult to be taken into account when designing 433 MHz antenna,a small microstrip antenna working in the ISM 433 MHz Band is designed by using the method of meander line technology and loading technology.By studying the influence of the key structure parameters on the antenna performance,the optimal method for designing antenna is proposed,and the validity and feasibility of the method are verified experimentally.(2)Aiming at the problem that the traditional miniaturization method cannot guarantee the antenna bandwidth and gain at the same time,combined with the demand of antenna polarization mode in vehicle,a small circularly polarized microstrip antenna covering the ISM 2.4GH and satellite TV band is designed based on the theory of compound right-hand transmission line.The feature of multi frequency and circularly polarization of the antenna are realized by constructing two asymmetrical compound right-hand transmission line structural units.By using HFSS software,the key structural parameters of microstrip antennas are optimized,so that the antenna has good input impedance,bandwidth,gain and circularly polarization characteristics at resonant frequency of the zeroth-order mode and the first-order mode.The experimental sample is made and tested to verify the feasibility and reliability of the design.