Research On Vehicle Acoustic Characteristics Analysis And Vehicle Recognition

With the electronic information technology's flying development, the collection of transportation information becomes more and more important to the management of the transportation intellectualization. The core of transportation information collecting system is transportation flow detection, the key is vehicle detection, velocity estimation and vehicle recognition. As an important part of intellectualized transportation, it applies widely in charge system, data statistics and so on, especially in highway automatic charge system, vehicle recognition play an extremely important role, because it is not only the main factor that determine the efficient of road transportation, but also the one of the important criterions for charging. In the present, the main method is to berry cable and induction coil under road, use camera to grasp the vehicle picture to carry on recognition. In addition, other methods also used in vehicle recognition, such as ultrasonic, microwave, infrared. Although these methods have matured sufficiently, they either are destructive to road, cost too much for later maintenance, or don't suit for use on a large area. With the development of sound recognition, these problem will be solved gradually, sound recognition including speech recognition, vehicle acoustic recognition, mechanical noise recognition, water acoustic and so on. Although it has simple equipment and convenient, it doesn't reach the mature stage, so if it uses with another method, it will be play an important role. This paper primarily carries on the analysis to the vehicle acoustic characteristic, then, researched on the vehicle recognition scheme by moving vehicle acoustic signal.In this paper, the development of vehicle recognition technology has been outlined by going through a lot of material in newspaper and references firstly, and then makes a contrast between vehicle acoustic and speech signal after analyzing their mechanism of the generation. The feasibility which process vehicle acoustic signal using speech signal processing method had been analyzed, and have a research on the extracting of vehicle's characteristic. This paper chose hidden Markov model as the foundation of recognition system, its principle is presented, give a sketch of three problem and basic algorithm, put forward a scheme procedure for vehicle recognition based on vehicle acoustic signal, discussed the realization of LPCC and MFCC with Matlab speech toolbox in detail. But in the recognition, this paper uses short-time energy, zero-crossing rate and pitch period as the basic of recognition. Since the paper is focus on analyzing vehicle's acoustic signal, it is the basic of recognition, so it only did a plan research in recognition.