Design And Application Of Multi-target Recognition Algorithm For Millimeter Wave Radar Based On Smart Car

The main body of the transportation system is the automobile.The intelligentization of the automobile will improve the active safety of the vehicle,alleviate road traffic congestion and reduce road traffic accidents.As one of the main sensors of smart cars,millimeter wave radar plays an important role in the active safety of automobiles.This paper designs the signal processing algorithm of millimeter wave radar system based on the radar kits of RKB1102 I and RKA1201 models,focusing on the constant false alarm detection algorithm,multi-target recognition algorithm,programming implementation of radar system and performance test of radar system.The main research work includes the following points:(1)Design the algorithm of each module of the radar system and verify it based on MATLAB simulation.First,the FIR filter is designed.Since the radar signal is disturbed by the external environment and internal components,there is high frequency noise,so the FIR filter is designed.Secondly,the design of constant false alarm detection algorithm,multi-target recognition,there are many interference targets,increase the false alarm rate,improve the CMLD-CFAR algorithm,add feedback mechanism,propose CMRFD-CAFR algorithm,reduce false alarm rate,detect Accurate target spectrum peak.Finally,the multi-objective pairing algorithm is designed.Because of the large computational complexity of the variable-cycle symmetric triangular wave multi-target pairing algorithm,the correlation between two different triangular wave signals is used to compress the pairing range and reduce the calculation amount.The feasibility and effectiveness of the algorithm are verified by simulation,which lays a foundation for engineering application.(2)Design a millimeter wave radar prototype system based on MCU.The control radio frequency generation and the radar signal processing are completed in the MCU,and the designed module program includes: a modulation signal module,an AD sampling module,an FFT module,a filtering module,and a communication module.In the modulation signal module,the DAC modulation mode is analyzed and implemented to generate a radar modulation signal.In the AD sampling module,the sampling module is analyzed,the sampling frequency and data bits are designed according to the radar ranging range,and the beat signal is acquired by the ADC.The characteristics of the FFT transform are studied,and its fence effect,spectrum leakage,frequency aliasing,and appropriate FFT transform points and frequency resolution are set to realize the Fourier transform of the beat signal.The radar chip is initialized by the MCU to drive the radar to work.Finally,the calculated target parameters are transmitted to the PC in real time through the communication module.(3)Verification and testing of the millimeter wave radar system.The frequency corresponding to the target is measured by the spectrum analyzer,the distance of the target is calculated according to the radar distance formula,and the result calculated by introducing the beat signal into the MATLB is compared to verify the effectiveness of the signal processing algorithm.Then,the 24 GH millimeter wave radar system is debugged,and different test scenarios are set.The single target and multi-target test are tested respectively,and the test results are analyzed to verify the stability and accuracy of the radar signal processing system.