Research On Angle Measurement Of Automotive Millimeter Wave Radar Based On MIMO

With the development of technology,Advanced Driver Assistance Systems are developing rapidly,and Millimeter wave radar has become an important and indispensable part of them.Because of its adaptability,all-weather operation,broad band and narrow beam,Millimeter wave radar is widely used in driving warning,automatic parking and auxiliary control scenarios.However,due to the limitation of its size and cost,the angular resolution of the radar is not high and the angular error is large,which restricts the behavioral decision of the driver assistance system.To address the contradiction between angular resolution and volume limitation,this paper improves the angular measurement method from two levels,focusing on the MIMO radar 3D-FFT angular measurement algorithm and the MIMO radar array optimization algorithm,and verifies the feasibility of the improved angular measurement algorithm on TI’s TDA3 x.In this paper,firstly,on the basis of FMCW radar,the basic theoretical introduction for different modulated signals is induced.And derive and analyze the application scenarios and characteristics of different modulation methods,and finally choose sawtooth wave as the signal basis of this paper research.Next,the array echo model is established,and after multichannel data acquisition and processing,the three-dimensional information of the target can be obtained.Different in-vehicle radar goniometric algorithms are detailed,analyzed and compared for goniometric algorithm performance,and finally 3D-FFT is chosen as the basic method for algorithm implementation in this paper.It is verified through Matlab simulation that the 3D-FFT goniometric method can effectively solve the problem of distance-velocity coupling of the traditional sawtooth wave,and the 3D-FFT algorithm can greatly improve the resolution of the target in terms of angle estimation,while an improved 3D-FFT goniometric method is proposed for the spectral estimation principle of FFT,which can effectively improve the goniometric error and increase the 3D-FFT goniometric accuracy.For the array optimization level,this paper studies the sparse array optimization method of MIMO radar array based on genetic algorithm.Considering that the genetic algorithm itself has the problems of easily falling into local optimal solutions and too many iterations,an improved genetic algorithm is proposed to address the above shortcomings by introducing multiple populations,classifying them into primary and secondary populations,and introducing a migration operator to achieve inter-population communication.By adoptingthe defined new population cooperative iteration method,the shortcomings of the traditional genetic algorithm can be effectively solved,and the iterative process can be ended earlier and the subflaps can be effectively reduced after the same number of iterations.The simulation results show that the proposed method achieves a more robust low-side flap directional map with a 2.6 d B side flap reduction.In terms of algorithm implementation,based on two AWR1243 P chips and TDA3 x multicore heterogeneous system implementation platform,this paper discusses the implementation of the system in detail in modules,and implements the vehicle millimeter wave mentioned in this paper on the multi-core heterogeneous processor of TDA3 x The algorithm flow of radar angle measurement improvement.Finally,experiments are carried out on stationary and moving targets,and the proposed improved angle measurement algorithm is verified.The obtained results show the feasibility and effectiveness of the improved algorithm based on 3D-FFT.