通过设计成像激光雷达的各种参数, 结合一种大气模式模拟得到了一维激光雷达信号, 并根据高斯分布的特点和实测的光束宽度还原了二维光柱图像。对该原始图像加入不同强度的高斯白噪声和一定强度的平均背景,生成类似于成像激光雷达实测信号的染噪图像。使用二维小波变换的方法对染噪的激光雷达光柱图像进行去噪, 获得了较好的去噪效果。去噪后的回波信号与原始回波信号之间的相对误差均在±12%以内。利用去噪的激光雷达信号反演出气溶胶的消光系数。将反演出的气溶胶消光系数与输入的大气模式下气溶胶的消光系数进行对比, 结果表明二者的相对误差在±15%之内, 并且总体变化趋势一致, 由此验证了所提出的利用小波对激光雷达染噪图像进行去噪的可行性。

One-dimensional lidar signal is achieved by the simulation combining an atmospheric model and the design of parameters of imaging lidar. A two-dimensional light cross image is recovered based on measured beam widths and features of the Gauss distribution. The noised images similar to the real signals detected by imaging lidar are obtained when we add Gauss white noise with different intensities and certain intensity of average background to the original image. The good de-noising effect is obtained when we denoise the noised lidar light cross image by the two-dimensional wavelet transform method. The relative error between echo signal after denoising and original echo signal is in the range of ±12%. The extinction coefficients of aerosol are retrieved with de-noising lidar signals. Comparing extinction coefficients under the input aerosol atmospheric model with retrieved extinction coefficients of aerosol, we find that the relative error is in the range of ±15% and their variation trends are coincident, which verifies the feasibility of the proposed method using wavelet transform in the de-noising for the noised images of lidar.