Vehicular Traffic Information Collection System Based On Zigbee Technology Research

Vehicular traffic information collection is an important part of the intelligent transportation system. Some accurate traffic parameters can be obtained through the collection and analysis of vehicle information. It provides reliable data for traffic management, traffic surveillance and traffic guidance, and greatly enhances the utilization of existing infrastructure. The disadvantages of existing detection methods and tools have led to the search for the new detector with the ability of flexibility, easy of installation, remote maintenance, precision and low cost. For the reason, in this thesis a wireless vehicle information acquisition system have been designed, which is based on ZigBee technology.ZigBee Technology has been analyzed deeply in the thesis, especially focusing on the building of ZigBee networks, such as the method for forming and maintaining the networks, the process of adding to the network and leaving the network. The network routing algorithm is also studied. Based on ZigBee protocol and combined with hardware resources, a small-scale star network have been designed and accomplished for the system.In the thesis, CC2430 is the core of the part of control; magnetoresistive sensors and seismic sensors are sensing elements of detection. Using those components designs the system hardware resources. The central node module, the child nodes connected modules, The seismic signal detection module, the magnetic signal detection module and the node power supply module are designed. Then using the above resources achieves the system hardware.Through analyzing the characteristics of magnetic perturbation signal, the thesis has proposed a automotive type recognition algorithm based on the average magnetic disturbance, and has researched a wave-based method to judge the direction of travel; speed estimation method based on the single node and dual nodes has been studied; combination of seismic signal, the thesis has proposed a algorithm mainly depends on magnetic helping with ground motion signals to determine whether vehicles passing by. Then it gives PC software design methods, and achieves initially the test results visualization. Laboratory and field experiments show that, the system has a certain validity and reliability.