Research On IF And Baseband Signal Processing For 24GHz Automotive Collision Avoidance Radar

Millimeter-wave radar becomes the mainstream technology of the international automotive radar in recent years. In this paper, in terms of 24GHz LFMCW automotive collision avoidance radar signal processing problems, three aspects about circuit system design, signal processing algorithms improvement and signal processing circuit implementation are studied in depth.First completed 24GHz automotive radar system design, designed back-end IF and baseband signal processing circuit based on the principle of FMCW radar and the radar front-end parameter index. IF signal processing performance affects the baseband signal processing directly, so select the best parameter through ADS simulation and repeated experiments. The baseband signal processing circuit includes DAC,ADC,gain control,FPGA and LCD, to complete controlling peripheral module and algorithm.Based on current radar algorithm and experimental initial results, we propose converting Triangular-wave frequency algorithm and spectrum matching algorithm. Baseband signal processing includes multiple frequency triangle wave modulation module, sub-gain module, FFT, spectrum matching and object extraction. The accuracy of radar range is improved by converting Triangular-wave frequency, when from 5 meters to 100 meters, ranging error is 0.15 meters to 0.7 meters, spectrum matching algorithm implementation is still in progress.Finally, analyzed the main reason for ranging error, will provide the reliable practical foundation for further performance optimization.