22-06-2011, 03:14 PM
Abstract
Tracking systems were first developed for the shipping industry because they wanted to determine where each vehicle was at any given time. Passive systems were developed in the beginning to fulfill these requirements. For the applications which require real time location information of the vehicle, these systems can’t be employed because they save the location information in the internal storage and location information can only be accessed when vehicle is available. To achieve Automatic Vehicle Location system that can transmit the location information in real time, Active systems are developed. Real time vehicular tracking system incorporates a hardware device installed in the vehicle (In-Vehicle Unit) and a remote Tracking server. The information is transmitted to Tracking server using GSM/GPRS modem on GSM network by using SMS or using direct TCP/IP connection with Tracking server through GPRS. Tracking server also has GSM/GPRS modem that receives vehicle location information via GSM network and stores this information in database. This information is available to authorized users of the system via website over the internet
Keywords—GSM, GPS, GPRS, GM862
I. INTRODUCTION
THE roots of Vehicle Tracking Systems lie in shipping industry. When large fleet of vehicles were spread out over the vast expanses of ocean, the owner corporations often found it difficult to keep track of what was happening. They required some sort of system to determine where each vehicle was at any given time and for how long it travelled. The need of vehicle tracking in consumer’s vehicle rose to prevent any kind of theft because Police can use tracking reports to locate stolen vehicle. [11] Initially vehicle tracking systems developed for fleet management were passive tracking system. In passive tracking system a hardware device installed in the vehicle store GPS location, speed, heading and a trigger event such as key on/off, door open/closed. When vehicle returns to a specific location device is removed and data downloaded to computer. Passive systems also included auto download type that transfer data via wireless download but the system was not real time. [10, 11] Passive systems weren’t useful to track consumer’s vehicle for theft prevention. Real time tracking system was required that can transmit the collected information about the vehicle after regular intervals or at least could transmit the information when required by monitoring station. Active systems were developed that transmit vehicle’s data in real time via cellular or satellite networks to a remote computer or data centre. [10, 11] Many vehicle systems that are in use now days are some form of Automatic Vehicle Location (AVL). It is a concept for determining the geographic location of a vehicle and transmitting this information to a remotely located server. The location is determined using GPS and transmission mechanism could be a satellite, terrestrial radio or cellular connection from the vehicle to a radio receiver, satellite or nearby cell tower. Other options for determining actual location, for example in environments where GPS illumination is poor, are dead reckoning, i.e. inertial navigation or active RFID systems or cooperative RTLS systems. After capture, the tracking data can be transmitted using any choice of telemetry or wireless communications systems. GSM is the most common used service for this purpose. [10, 11] A. Objective
