A Speed Measuring Method Based On The Vehicle Compound Audio Research

The serious problem of traffic congestion and urban efficiency is received attention withaccelerating the pace of urbanization and automobile holdings soared in China. The traffictransport efficiency and traffic safety can be improved by Intelligent Transportation System(ITS-Intelligent Transportation System). Traffic detection technology has become importantpart of ITS. The traffic detection technology using acoustic, especially the detection using thetraffic noise, is a kind of more economic and convenient detection method. The advantage ofthe detection using the traffic noise is convenient management, small capital investment.Traffic detection can be effectively determined using road real-time noise. The value of thetraffic detection using vehicle noise has been extensively applied in automatic statistics,traffic monitoring, noise control, etc.In order to solve the problem of speed detection in traffic. This paper puts forward a kindof speed measuring method based on the noise of single car. This method collects single car’snoise and then analyzes the noise with Fourier transform by a series of signal processingmethods. The speed of the car is estimated according to the relationship between the speedand the Doppler frequency shift. By taking the experiment, we verify that this method isreliable and efficient under the certain experimental conditions.In this paper, vehicle traffic noise of environmental noise is researched. Thecharacteristic of vehicle noise signal of noise source is analyzed. The traffic detection isachieved using vehicle traffic noise. Experiment of this paper, the received signals is the noisesources generated a single vehicle traffic noise of a signal microphone on the lane. Estimationthe vehicle speed of different types is used to determine the mathematical model of thevehicle traffic noise and Doppler frequency shift. The result of vehicle speed estimation iscompared with the actual vehicle speed. This speed estimation can be applied to the trafficdetection technology.