脉冲压缩在激光测距中的应用

摘要

The pulse laser range⁃finding and phase laser range⁃finding are the main methods of laser range⁃finding presently, but they may lose efficiency easily in complex noise environment due to oblivion of echo signal covered in the noise. Since the weak echo signal is difficult to extract,the pulse compression laser range⁃finding method is proposed. The pulse laser of linear frequency modulation is emitted,and received with pulse compression technology to increase the pulse peak power,improve the signal⁃to⁃noise ratio,and obtain the echo signal covered in noise. The method has important research significance and application value to improve the range⁃finding distance and reduce the laser power. The mathematical model of pulse compression method in laser range⁃finding was established. The typical Gaussian white noise environment was simulated. The influence of pulse compres⁃sion parameters on the laser range⁃finding is analyzed. The laser signal source of linear frequency modulation was designed,and the pulse compression signal processing was realized based on FPGA.%脉冲式激光测距和相位式激光测距是目前主要的激光测距方法，但是在复杂噪声环境中，容易因回波信号湮没于噪声中而失效。针对微弱回波信号的提取难题，提出了脉冲压缩式激光测距法。通过发射线性调频的脉冲激光，接收时采用脉冲压缩技术提高脉冲峰值功率，改善信噪比，从而获得湮没于噪声中的回波信号。该方法对于提高测距距离和降低激光功率具有重要的研究意义和应用价值。建立了激光测距中脉冲压缩方法的数学模型，并针对典型高斯白噪声环境进行了仿真，分析了脉冲压缩参数对测距的影响，设计了线性调频的激光信号源并基于FPGA实现了脉冲压缩信号处理。