Development Of Remote Communication Unit And Its Protocol Stack Based On GPRS For Electric Vehicle

Electric vehicle are widely developed because of the scarcity of oil and thepollution of common vehicle. China founded an "863" project for electric vehicle. Inorder to facilitate the development of electric vehicle, it's necessary to develop aremote monitoring system for electric vehicle. The remote monitoring center canmonitor the state data of electric vehicle and also can send commands to electricvehicle to modify some parameters of electric vehicle in order to optimize electricvehicle. The writer has developed the remote communication unit based on GPRS forelectric vehicle.The process of communication, the design and realization of communicationprotocol stack, the design of hardware for communication terminal, the encryptionand decryption of data and the function and design of monitoring center areintroduced in this paper. And also the monitoring center can choose data needed andset the frequency of data. The transition of state machine assures the reliablecommunication. When the link is disturbed, it can be reconnected. The writer alsotested the quality of communication. The maximal communication rate can reach20kb/s. The delay of communication is about 0.5ms.The remote monitoring system based on GPRS has been equipped in electricvehicles. The system is reliable and easy to manipulate. The system can be easilymodified to apply in the remote data sample and control.