The LFMCW Automobile Anti_collision Radar Signal Processing And Hardware Implementation

Automotive anti-collision radar is mainly used in the field of Driving Assistance,which can effectively reduce the incidence of traffic accidents by providing danger warning for the driver. At present, Automotive anti-collision radar has already applied in Europe and other developed countries, however, The study of this field in our country is still in the laboratory test. The signal processing is the central issues of the while system,so the work of this paper for the signal processing and implement has important engineering sense to the develop of Automotive anti-collision radar.In this paper, we design a hardware platform system for the signal processing,where LFMCW signal based on the triangle wave modulation is used. The picture of real products and the test results are also give in this paper. The hardware circuit design based on FPGA + DSP and the main algorithms for baseband signal processing, such as,baseband signal pre-processing, constant false alarm algorithm, Angle measuring algorithm etc, which are the focus of this paper. The overall writing ideas of this paper are as follows:1. Discussing the application scenarios and the research value of automotive anti-collision radar, introduces the current situation and development trend of the automotive anti-collision radar;2. Introducing the advantages and the basic principle for speed, distance and Angle measurement of LFMCW radar. Next, The general structure of the automotive anti-collision radar system designed in this paper is provided. The system parameter and modules function are also introduced according to the actual demand.3. Designed a hardware platform based on FPGA + DSP for signal processing.Mainly discussed the designing methods of the main modules, such as, the AD sampling circuit, the configuration circuit for FPGA and DSP and the peripheral communication interface circuit. Finally, Giving the design method of PCB and final circuit hardware.4. Introducing the signal processing flow based on Automotive anti-collision radar,and simulation main algorithms of the system. Mainly including digital down-sampling,constant false alarm processing(CFAR) and Angle measuring. The simulation results compared the detection performance and their advantage and disadvantage of different constant false alarm processing(CFAR) algorithm. The simulation performance of thedouble antenna angle measurement algorithm indicate the relationship between the angle measurement accuracy and the Doppler frequency, signal to noise ratio(SNR).Giving the board test results of each module, the test results show that the hardware design for the baseband is corrected. Field test with rf circuit, the field test results show that the radar system designed in this paper can accurately calculate the speed, distance, and other information of the target, meeting the basic requirements of the system.