Study On Methods Of Target Recognition With Vehicle Millimeter Wave Radar

In recent years,cars become a common means of transport for people with the rapid development of the automotive.And people pay more attention to the safety when they drive.As an important vehicle sensor,automobile millimeter wave radar plays an important role in automobile safety system.This paper discusses the method of target recognition with vehicle radars based on the research of millimeter wave radar system and does some research on target recognition method based on single-radar and dual-radar system.First of all,the working principle of radar is studied.The relevant factors affecting the effectiveness of radar are discussed.The radar operating system used in this paper is the continuous wave system and the working frequency band is 77GHz,which means it is a MMW radar.The intermediate frequency signal is introduced.The structural composition of the millimeter wave radar system can be divided into three modules:antenna module,RF front-end and micro processing module.It helps understand the function of the main electronic components of each module and the influence on the radar system.The working process of millimeter wave radar system is presented according to the millimeter wave radar used in this paper.Secondly,a target recognition method based on velocity feature is proposed.The radar operating system is set to a constant frequency continuous wave,so the extraction of velocity feature can be easier.The fast Fourier transform method is used for the frequency spectrum analysis,and the improved algorithm is used to refine the spectrum.The Gauss function is used to estimate frequency,and the accuracy of velocity measurement is improved.Threshold judgment classifier is established based on velocity feature.Then,a target recognition method based on dual radar system is proposed.The method uses two millimeter wave radar installed in the car,so information each radar obtained is different.Then the same type of characteristics is extracted to establish characteristic matrixes.Distance and velocity features of the target can reflect the shape and motion characteristics,so the distance and velocity matrixes are established.There is a transition matrix between the two radars,which can be used to represent the target's action mode and shape feature.In the recognition stage,calculation results of a primitive feature matrix and transformation matrix are operated with the other primitive feature matrix for column correlation analysis.Degree of correlation between the characteristic matrix and transformation matrix can be obtained,expressed by the correlation coefficient.Correlation coefficient can be analyzed to finish the target recognition with dual-radar system.Finally,the experiment and simulation of the radar target recognition methods with the single-radar and dual-radar system are presented in this paper.Experimental and simulation results show that target recognition method based on single radar can distinguish most of the targets,but there are still some defects;and target recognition method based on dual radar system can accurately identify the target,which is important to the research of the target recognition method.