为了对激光雷达探测回波信号去噪进行研究, 基于小波阈值法分析了激光雷达发射和探测回波信号, 创建了基于MATLAB仿真平台的模型,研究了阈值法中选择各参量的策略, 结合激光雷达信号和噪声特性, 选取了去噪处理中的最佳参量, 并进行了4种阈值策略的仿真实验, 实现了对探测回波信号中目标信号的有效提取和去噪。结果表明, 对于低信噪比信号, 同一基函数分解层越高去噪效果越好, 在分解层数j为4~5时去噪效果最好; 对于高信噪比信号, 同一基函数分解层越低去噪效果越好, 在j=3时去噪效果最好, 并且信号db9基函数去噪效果好于db2基函数去噪效果。此研究获得了较为理想的去噪结果。

In order to study the de-noising of laser radar detection echo signal, the laser radar transmitting and detecting echo signal were analyzed based on the wavelet threshold method, and a model based on MATLAB simulation platform was created. The strategy of selecting the parameters in the threshold method was studied, and the best parameters in the denoising were selected combined with the characteristics of the laser radar signal and noise. The simulation experiments of four kinds of threshold strategies were carried out to achieve the effective extraction and denoising of the target signal in the detection echo signal. The results show that, for the low signal-to-noise ratio signal, the higher the decomposition layer of one base function is, the better the denoising effect is. The de-noising effect is the best when the decomposition layer j=4~5. For the high signal-to-noise ratio signal, the lower the decomposition layer is, the better the denoising effect is, the best at j=3. And the denoising effect of the signal db9 base function is better than that of the db2 base function. An ideal denoising result is obtained in this study.