Design And Verification Of Vehicle-mounted ACC System

With the social and economic development and the gradual increase in the number of vehicles, road traffic accidents occur frequently, causing huge economic losses and threaten people’s lives and property. Improve vehicle safety performance and reduce traffic accidents have become an issue of public concern. ACC-vehicle active safety systems as a driving assist device that can accurately detect the distance, speed and angle of the vehicle in front of the goal, to detect potential threats, and to take appropriate measures to ensure traffic safety. ACC-vehicle system is one of the effective measures to improve traffic safety, it gets more and more research attention.This paper designs a ACC-vehicle system using 24 GHz millimeter-wave radar.Millimeter-wave radar has a better environmental adaptability, strong anti-jamming and low-speed moving target detection and identification capability.For lack of traditional frequency-modulated continuous wave(FMCW) In the case of multi-objective, using a modulation waveform FMCW+CW radar, not only can effectively solve the problem of false targets multi-objective case, and help reduce the amount of computation, simplifying system architecture and reduce costs.In this paper, in the form of an antenna to transmit and two receive, To detection target azimuth angle, practical applications can effectively reduce false positives non-threatening to the vehicle in front of the goal footbridge,isolation belt, trees, etc., to reduce false alarm probability and improve reliability.This paper introduces the research background of Car ACC systems, radar works and FMCW radar guns ranging principle, and to study the single-pulse angle measurement methods(including azimuth and elevation). Then, the paper deeply study on hardware circuit design, implementation and interface functions and radar signal processing algorithms and other aspects of the system.The system uses the FPGA and DSP co-processing hardware implementation, full use of the advantages of fast speed DSP and FPGA processing large quantities of data, increasing the co-processor ADSP BF-537 complete with communications and computer network data transmission.This paper then introduced the ACC system radar signal processing algorithms and related processes, including: band pass sampling, digital down conversion, splitting complex sequence based fast Fourier transform, windowing, frequency domain CFAR processing, target cohesion, peak search, multi-target recognition and tracking, and using MATLAB simulation.Finally, the on-board systems within ACC road games live experiments and tests, record test results and analysis of the measured signals, the test results show that the system performance indicators meet the design requirements preliminary to good effect. In addition, summed up shortcomings and problems still exist, the prospect of work and future research directions.