Design And Implementation Of 77G Millimeter Wave Automotive Anti-Collision Radar

With the development of automotive advanced driver assistance systems(ADAS),millimeter-wave radar,as an active sensor,has the advantages of working all-weather,long detection distance,high ranging accuracy,and strong weather adaptability.Compared with expensive Lidar It has obvious cost advantages and has become a key sensor for vehicle assisted driving.However,the traditional single-channel vehicle radar solution has the shortcomings of limited detection range and low angular resolution,which severely restricts the application of millimeter wave radar.This article focuses on the signal processing flow of the automotive radar,studies the methods to improve the performance of the radar,and presents the software and hardware schemes of the two-chip cascaded vehicle millimeter wave radar overall system.The main tasks of the thesis are:Firstly,the signal processing principle of LFMCW millimeter wave radar is analyzed,and the basic formulas of range,speed and angle measurement are derived.In ranging,the maximum detection range is obtained by combining the radar equation;In speed measurement,according to the principle of speed measurement,the causes of speed ambiguity are analyzed.In the aspect of angle measurement,from the angle of increasing angle resolution,this paper analyzes the working principle of MIMO(multi input multi output)array antenna and the improvement of angle measurement resolution by beamforming.Finally,for target detection,constant false alarm detection(CFAR)algorithm is analyzed to lay a theoretical foundation for the follow-up research.Then,the factors affecting the radar precision in the actual signal processing are studied,including the influence of radar power on range range,spectrum leakage,Doppler phase deviation,and the derivation and Simulation of near-field effect.Then,for the speed fuzzy problem,the maximum speed measurement range is increased to three times that of the original one by using the algorithm of solving the speed fuzzy algorithm based on the Chinese residual theorem.Then,the signal processing and analysis of echo data collected in different scenes are carried out to verify the feasibility of two-dimensional distance velocity FFT ranging.Finally,complete the schematic design of the hardware power supply and peripheral interface of the automotive millimeter wave radar system,and then complete the production and testing of the prototype of the two AWR1243P cascaded radio frequency board and TDA3x signal processing board.Finally,two basic working modes of TDM-MIMO and beamforming scanning are set up to meet the requirements of long-distance and shortdistance 3° angular resolution detection,and the software implementation of the vehicle radar signal processing algorithm in the TDA3x processor is given.