Study On The Tire Pressure Monitoring System

With the development of social economy and technology, road transportation has been playing more and more important role in our life. But the traffic accidents do a great damage to our life and make a lot loss to economy. Tire blowout is the main cause. The keypoint to avoid tire blowout is to hold standard pressure and aware of the leakage of tire in time. Tire Pressure Monitoring System (TPMS) is mainly used to monitor tire pressure while running and alarm the leakage and low pressure of tire, so it is a safeguard to drivers and passengers.There are two different kinds of TPMS: Pressure-Sensor Based TPMS and Wheel-Speed Based TPMS. In this thesis, the operational theory of PSB TPMS and WSB TPMS are introduced in detail. A detail description is given from pressure sensor, single-chip controller, RF transmitter and receiver, batteries as well as LCD, based on measurement precision, low power consumption and cost. Then a full TPMS scheme based on the pressure sensor and RF transmitter and receiver of Infineon Technology is given and at last the measurement of tire pressure & temperature are measured timely and correctly.In this thesis, the hardware circuit and software program are introduced in detail. The hardware consists of two parts, tire pressure measurement & transmitting part and receiving & display part. Tire pressure measurement & transmitting part consists of pressure sensor, single-chip controller and wireless transmitting & receiving components, and is used to measure the tire pressure and transmit the information; The receiving & display part consists of wireless receiver, single-chip controller and LCD, and is used to receive and display the tire information. There is a detail study on power consumption, and by taking the wake-up mode the current consumption is reduced and the batteries life-span is prolonged. The software flow as well as the software program is given, and at last the tire pressure and temperature are measured accurately; In the end, there is a analyse about restriction of the scheme, and the solutions to solve the problems are given.