Antenna Design Applied In Tire Pressure Monitoring System

Tire pressure monitoring system(TPMS)is an automotive safety assistance system that monitors tire pressure and temperature in real time and warns drivers of abnormal tire conditions in advance.Although the tire pressure monitoring system has been successfully commercialized,there are still many areas that can be improved to save the overall energy consumption of the system.This paper designs a miniaturized,high-bandwidth,high-gain,high-radiation-efficiency transmitting antenna in the Bluetooth frequency band(2.4-2.4835GHz)for the transmitter of TPMS to reduce the volume of the transmitter and improve the stability of data transmission.It can save energy and improve the service life of the equipment.The structure and main contents of this paper are as follows:The structure and main contents of this paper are as follows:(1)Investigated the development of TPMS,expounded the development and current situation of TPMS at home and abroad.Some current TPMS antenna design schemes are studied and their advantages and disadvantages are analyzed.The development of loop slot antenna(WHEMS antenna)is briefly introduced.(2)Introduces the basic knowledge about antennas,including some basic parameters of antennas,and expounds some methods to improve antenna gain and antenna miniaturization,and use these knowledge and methods to assist the design of antennas in this paper.(3)According to the existing problems of TPMS,the design index of the antenna in this paper is put forward,and the design process of the antenna applied in TPMS is introduced in detail,including the research and design of the antenna parameters in the simulation,and the comparison and analysis of the actual measurement and simulation results are carried out.The antenna is miniaturized,and at the same time meets the characteristics of high bandwidth,high gain,and high radiation efficiency.(4)Put the antenna designed in this paper into the tire to simulate the actual situation simulation and measurement,observe the electromagnetic radiation characteristics inside the tire,and observe the radiation performance of the antenna designed in this paper inside the tire to meet the design requirements of the antennaThe antenna has been simulated and measured,and the final size of the antenna is controlled at 42*21.5*10mm.The actual measurement results show that in the Bluetooth frequency band,the maximum gain in the single antenna test band can reach 2.6d Bi,the impedance bandwidth can reach about 250 MHz,and the antenna efficiency is about 85%.;Put the antenna into the tire for actual measurement.Since the hub of the tire and the metal mesh face the antenna and act as a reflector,it is measured in the darkroom that the maximum gain in the far-field band can reach 8d Bi,and the radiation efficiency can reach about 80%.The characteristics of high gain,high bandwidth and high radiation efficiency can meet the use of energy-saving TPMS transmitting antennas.