Research On Multi-beam Angle Measurement Technology Of 77G Vehicle Radar

With the rapid development of driverless technology,advanced driver assistance system technology has become more mature.The vehicle radar is an important part of advanced driver assistance systems,which can detect the front and rear directions of a vehicle and blind spots in the driver's field of vision.So it can reduce the incidence of traffic accidents and protecting pedestrians.The 77 GHz millimeter wave radar is widely used in advanced driver assistance systems due to its large bandwidth and high resolution.Compared with ultrasonic,camera,LiDAR and other sensors,it has strong antiinterference ability and can adapt to the environment well.Therefore it has a good detection effect under severe weather conditions.This thesis studies the angle measurement method of the vehicle radar based on the platform of 77 GHz millimeter-wave radar AWR1642.Firstly,the simulation analysis of signal processing flow in the fast slope mode and traditional angle measurement methods is carried out.This thesis focuses on virtual aperture angle measurement method for MIMO radar(using FFT to form multiple beams).Then,some new improved methods for different vehicle radar applications has been proposed.Finally,the radar signal processing flow is implemented on the AWR1642 evaluation board.The purpose of this thesis is to study the angle measurement method of vehicle radar.The main work is as follows:1.Aiming at the shortcomings of traditional LFMCW in range and velocity measurement,the fast slope mode waveform is selected as the transmit waveform in this work.The waveform characteristics and related simulations of signal processing flow are analyzed,including range and velocity measurement and constant false alarm detection.2.The related methods of LFMCW radar angle measurement are studied.The advantages and disadvantages of several methods such as three antenna phase angle measurement,virtual aperture angle measurement method for MIMO radar,DOA estimation MUSIC algorithm,Doppler beam sharpening method are analyzed.The virtual aperture angle measurement method for MIMO radar is deeply studied as the chosen angle measurement method in this thesis.3.According to the requirements of different vehicle radar applications,three improved methods based on virtual aperture angle measurement method for MIMO radar are proposed.Including virtual aperture angle measurement method for MIMO radar based on frequency division multiplexing technology,the method simultaneously resolving ambiguous speed and measuring angle,and the angle measurement method by using sum and difference beam of vehicle LFMCW radar.Simulation analysis is performed to verify the feasibility of each method.4.By studying the hardware and software implementation of AWR1642,the hardware block diagram,software signal processing flowchart and software data flow diagram are presented.The RF subsystem of the AWR1642 hardware platform is configured on the CCS development platform,and finally the signal processing flow has been debugged.