Design And Implementation Of Vehicle Monitoring Centre Based On GPRS/SMS

Intelligent Transportation System (ITS) is the front of the present international road traffic and development in science and technology for transportation. As an important component of ITS, Vehicle Monitoring System becomes the focus of studying.This paper analyses the advantage and disadvantage of the commonly used communication scheme in detail, introduces the new characteristic of GPRS network and proposes the communication scheme based on GPRS/SMS. The realization principle of GPRS network is analysed. In addition, SMPP interface protocol of SMSC and China Mobile CMPP interface protocol of ISMG are also researched, and then this paper designs and realizes the communication server of the Vehicle Monitoring Centre.SMS has advantage of widely covered and GPRS has advantage of high transmission rate, so combining GPRS with SMS to realize Vehicle Monitoring System is the best choice at present, which has the large coverage and high user capacity. In the area where GPRS network covers, vehicle can use GPRS network to transmit data. Without GPRS network, vehicle can use SMS to transmit data.A large number of vehicles are connected to communication server through TCP/IP, so communication server must provide service for a large amount of I/O request at the same time. In order to realize the high-performance network application program, "Winsock I/O Model" should be used, in which "I/O CompletionPort Model" can manage lots of winsocks and obtain the best system function. With "I/O CompletionPort Model", vehicle winsock can be managed, the highest transmission rate can be obtained, and the high-performance communication service can be realized.In the Vehicle Monitoring System, GIS occupies very important position. It can show vehicle position in real time and provide graphic user interface. MapX is a GIS componet that MapInfo company provides. Besides finishing GIS function, it also has characteristic of succinct system structure, strong graphic function and small system scale. Finally, on the basis of MapX, this paper designs the system architecture of the software and describes the realization of all function modules in detail.