Design And Realization Of Auto Access And Tire Pressure Monitoring System

With the rapid development of auto industry,more and more electronic systems are widely used in the vehicles.At present,the system has some problems just like hardware redundancy, big space, the high cost and relatively higher failure rate and so on.Therefore,optimizing automobile electronic system and improving the network integration have become a key research at home and abroad.At present,the remote entry control system and pressure-sensor based tire pressure monitoring system are widely used.For both have the same RF communications characteristics. This paper designs a solution that bases on system integration technology car access and tire pressure monitoring system, by sharing the same base station in the car radio receivers and improving the remote entry control system of the RF communication protocol.According to the system seheme, the design for hardware and software of tire module, keyhead module and base station module. For the system of tire module omni-directional, high-gain ones, The design of a kind of characteristics of small size, high gain mouth type valve omni-directional antenna, this antenna is tire module's antenna.At the same time , it can replace the valve functions such as filling, releasing air, and still can completely dispel rim shielding effect. As for the problems are that key space is small and low power consumption requirements, the the core integration of the IMMO and single chip solutions (RKE CombiChip) PCF7961 to realize engine burglarproof Low-Frequency communication authentication and remote keyless entry commands.To the tire module is a very sensitive equipment for power consumption through the combination of awakening at a fixed time and the acceleration sensor,reducing the RF power transmiting time, in order to realize its power consumption. Due to Keeloq technology's Hardware exists highly cost, full-featured,scalability, issues and so on. On the basis of analysis the Microchip company's Keeloq in hardware encryption algorithm realization mechanism, through introducing the random, using software ways to realize Keeloq encryption algorithm to reduce the hardware overhead and increase the flexibility of the system. Finally, using the product prototype to have an actually loading test,the experimental result suggests that the develop product prototype reaches the design target in cost, power consumption,communication distance and security. At the same time it provides for a practical and effective method for optimization of automotive electronic systems.