Research On Wireless Traffic Flow Detection Technology Based On Geomagnetic Sensors

City traffic congestion affects the city traffic operation efficiency,slows down the social productivity and becomes one of the important factors restricting the development of our urban.Intelligent Transportation System(ITS)has attracted attention of countries gradually as a means of mitigating the urban traffic block and improving the operation efficiency of traffic.Vehicle detection technology as an important part of Intelligent Transportation System,through accurate obtain the real-time traffic information,to provide the necessary data for ITS,real-time monitoring and intelligent traffic management.And then realize the vehicle detector based on magnetoresistive sensor has the advantages of small size,high sensitivity and easy installation features,it makes up for the shortcomings of traditional detectors.At the same time,the increasingly complex network of cities,mostly no traffic control equipment network withthe monitoring center,the existing equipment upgrade potential network is imperative,for vehicle inspection the development of measurement technology provides a new direction.The research contents and achievements of this paper include the following aspects: 1,This paper focuses on the research of ITS in vehicle detection and traffic monitoring equipment network upgrade method,based on the design of the new vehicle detector and based on magnetoresistive sensor and intelligent gateway nodes in STM32F407.The data acquisition,the design optimization model and algorithm of traffic data collection based on ZigBee wireless sensor network,to achieve the vehicle classification such as vehicle flow,speed and real time traffic data.The wireless sensor network without wiring,flexible networking and large-scale deployment,has an excellent application prospect in ITS.2,Comprehensive research and analysis the method of traffic monitoring equipment connected to the network at home and abroad,a design based on intelligent gateway module STM32F407 has been presented.At the same time the design of coordinator and data transmission protocol of intelligent gateway protocol has been proposed,mainly includes host ID,ID node and traffic information system,etc.The received data from gateway in TXT format to the SD card.The gateway module with low power consumption,high performance,low cost and easy to use development advantages,to achieve the traffic data upload,storage,WEB access and other functions,to achieve the network vehicle detection system of the target.3,We design the whole software and hardware for the wireless sensor node and geomagnetic intelligent gateway module.The acquisition vehicle detector experimental data through the detection area,in-depth analysis of the vehicle detection signal is proposed based on the mean square deviation of vehicle detection algorithm based on adaptive threshold,by analyzing the experimental data,detection algorithm this paper designs the detection accuracy reached 99.4%.For speed detection,by using the method of double point velocity measurement,the experimental results show that the detection accuracy of 90%.this algorithm has high detection accuracy,leakage detection and low false detection rate,can detect the traffic information timely and accurately,provide timely and efficient traffic flow data for dynamic traffic light regulation.