Research On Radar Signal Processing Of Vehicle Active Anti-collision Warning System

Vehicle Active Anti-collision Warning System can prevent the happening of theaccidents effectively and improve vehicle active safety significantly. This system can alsoassist the driver and reduce the driver’s fatigue. So its research and application has get moreand more attention. Based on the innovation project of Science and Technology Departmentof Jilin Province------"Vehicle Active Anti-collision Warning System Research andDevelopment", this paper has researched on the radar system and Intermediate Frequency(IF)signal denoising for this system. Its main contents are as following:At first, this paper puts forward the performance requirements of Vehicle ActiveAnti-collision Warning System. It chooses to use Frequency Modulated ContinuousWave(FMCW) radar system and discusses the basic structure and working principle of thisradar. Then the principle of Linear Frequency Modulated Continuous Wave(LFMCW),Frequency Shift Keying(FSK) and Stepping Frequency Modulated ContinuousWave(SFCW) system was reaserched. By comparing these three typical FMCW system letsthe radar work on LFMCW-FSK joint system and analyzes target information acquisition ofthis system.Secondly, it analyzes the IF signal of active anti-collision warning radar and thecharacteristics of its noise. And the basic algorithms of Kalman Filter, Empirical ModeDecomposition(EMD) and wavelet transform was learned. Then based on the algorithms ofthree methods designed the flow chart and procedure for IF signal denoising. These analysisestablished the theory and application foundation for IF signal denoising simulation.Thirdly, this paper built simulation model of active anti-collision warning radar whichcontains the target model, radar transmitter model and radar receiver model. Based on thesystem requirements it desinges the radar system parameters. Combined the radar modeland parameters do the simulation on relative static and relative motion targets. The analysisof the simulation results reflect that the system and parameters that this paper designed are reasonable and effective.Finally on the basis of the previous reaseach,it uses the MATLAB do the simulation ofIF signal denoising. And then compares and analyzes the denoising effect of kalman filter,EMD and wavelet transform. At last discussed the internal relations between the threedenoising methods and the modulation waveform types.The research results of the collision warning radar system and its IF signal denoisingare conducive to achieving rapid and accurate detection and recognition of targets, thediscrimination of targets’ dangerous level and automotive active warning. These lay thetheoretical foundation for the development of signal processing in anti-collision warningradar and also have a certain guiding significance and practical value in its futureapplication and promotion.