Research And Implementation Of High Resolution Lidar Ranging Technology Based On FMCW

Since its inception,lidar ranging technology has been widely used in various fields such as military battlefield reconnaissance,weapon guidance,unmanned autonomous positioning and navigation,underwater detection and marine resource exploration,and atmospheric environment monitoring.It has very broad application development prospects..How to improve the resolution of laser ranging is a hotspot and frontier in the research field of laser ranging radar,and it is also a key technology that needs to be solved continuously in this field.The thesis mainly focuses on related research on laser ranging technology based on Frequency Modulated Continuous Wave(FMCW),focusing on the direction of improving the ranging resolution through the refinement algorithm of spectral resolution.The principle of FMCW laser ranging is to establish the relationship between the signal frequency and the flight time of the laser in the air through the modulation of the optical frequency,thereby converting the measurement of the distance into the measurement of the frequency.In the FMCW laser ranging system,digital signal processing technology based on spectrum analysis is usually used to process data at a high speed.The most typical representative is FFT(Fast Fourier Transform),which can be combined with hardware chip technology and computer technology.Fast processing of data calculations with a huge amount of calculations.Based on the research and analysis of the frequency correction algorithm based on FFT theory,the paper designs a spectrum refinement scheme for the difference frequency signal of the FMCW ranging system,and proposes a comprehensive spectrum processing algorithm strategy: through ZFFT(complex modulation fine The FFT algorithm locally refines the frequency spectrum of the difference frequency signal to improve the frequency accuracy and indirectly achieve the purpose of improving the ranging accuracy.Considering the real-time requirements of algorithm applications,the paper designs a comprehensive spectrum analysis and processing method based on SFFT(Sparse Fourier Transform),which achieves the design goal of reducing the complexity of the algorithm without serious degradation of the estimation accuracy.Then,the paper verifies the feasibility of the algorithm scheme in the signal processing application of FMCW laser ranging system to improve the system's ranging resolution through theoretical derivation and simulation analysis.In the final paper,the actual distance measurement experiment was carried out,and the analysis of the experimental results showed that the comprehensive algorithm improved the frequency resolution in the signal processing of the actual FMCW laser distance measurement experiment,and the calculation efficiency was high,and the operation time and resources were saved,thus verifying The feasibility and effectiveness of the design of the thesis have engineering application value.