REAL TIME TRACKING CONVEYANCES AND BIDIRECTIONAL DATA COMMUNICATION

Due to substantial progress in (micro )electronics and the fast growing calculating capabilities of small computing systems real time remote vehicle tracking even with high precision became available for a lot of potential users. At this moment a lot of different equipment became available on the market based upon different techniques so that it is actually complex to make a choice. Depending on specific requirements (maximum time delay- confidentiality- ... ), needs (coverage of one country- more countries - ... ) and other limitations (a few vehicles at a moment or more than one hundred vehicles simultaneously to be tracked) there can be different solutions to cover a case. Basically a system will consist of three main constituents : • a system to locate the vehicle (positioning); • a system to transmit this information to the tracking station; • a system to visualise this information. In its most simplified fonn a tracking system could consist in a driver transmitting his position on a regular time schedule by radio or mobilophone. In order to enhance confidentiality, and in the case of a predetermined routing, fixed points can be coded and this code transmitted by mobilophone or HF radio transmitter to the tracking station at the moment that each point is reached. Although such a system could still work, nowadays easier and more perfonnant systems should be preferred.