Analysis And Improvement Measures On Electromagnetic Compatibility Of Tire Pressure Monitoring System

Tire pressure Monitoring System(TPMS)is used to monitor tire pressure and temperature automatic in the tire of vehicle and it can emit early alarm about abnormal condition such as flat tire,lower or higher pressure and higher temperature, so this system has the features of shorten the using cycle of tire,decreasing the frication damage of vehicle components and reducing the fuel consumption of environment-friendly.With the increasing number of automotive electronic equipment to be used, such as Wiper,GPS,Audio System and PEPS system and so on, the electronic environment in the vehicle has been increasingly complexity. Additionally, the outside electromagnetic environmental which mainly come from power network,thunder and light,radar,neighbor cars and high frequency induction furnace produced is also bad. Those electromagnetic interference could make TPMS ineffective, so analysis EMC,test EMC and design strategy of EMC have certain realistic meanings.In order to improve the EMC robustness and reliability of TPMS,this dissertation has researched two points containing EMC analysis and EMC improvement. To be aimed at these two aspects, the main contents are illustrated as follows.Firstly, the dissertation have presented the status of TPMS and EMC in china and abroad in detail and elaborated on the fundamental theory of EMC. And those work would laid the foundation for blow contents.Additionally, analyze the EMC performance of TPMS and actually testing EMC performance of TPMS in two aspects containing EMI and EMS. Then, simulate the bearing interference ability of various modulations in TPMS communication channel by various simulations.Then,sorts of strategies to restraining the electromagnetic coupling between antenna were proposed. Firstly, an antenna system which conforms to TPMS was designed. This content contains the structure design and the matching circuit design of antenna. And then simulate the antenna system using the source routing simulation software HFSS. Finally, according to the antenna system designed before, a coupling model was proposed. Next, sorts of strategies to restraining the electromagnetic coupling between antenna were proposed, and those work based on simulation by Matlab. Finally, taking design of TPMS receiver module as example, we put forward the way to improve the EMC of PCB. Then, outputting the DXF file of the PCB which designed by the Protel to the "YSYE" (You See, You Get) application software which is called Ansoft designer. Then simulate the anti-interference characteristics of PCB. And the simulation result shows that these strategies are reasonable.