基于光子计数激光雷达的时域去噪

激光雷达传统的成像方法需要经过长时间积分探测生成光子计数统计直方图的方式来减少背景噪声的影响,获得目标场景的深度估计信息。为了快速准确地获取目标场景的3D图像,提出基于光子计数激光雷达的三维距离图像时域去噪算法。该算法不需要生成光子计数统计直方图,利用信号和噪声在时间轴上不同的分布特性,结合了泊松过程统计规律。此算法提高了信号的探测概率,能够在低信噪比的环境下将信号和噪声分离,获得目标场景准确的3D图像。实验结果表明在低信噪比的条件下,此算法获得深度图像的RMSE与传统基于最大似然估计成像方法相比成像精度至少提高了3倍。有利于激光雷达三维成像在高背景噪声环境下的使用,拓宽了激光雷达的应用范围。

Time-domain denoising based on photon-counting LiDAR

For decreasing the effect of background noise, the traditional imaging method of laser radar requires take long time in accumulation sampling and generating statistical histogram of photon countingto obtain the depth estimation of target. A 3D time-domain denoising algorithm based on photon-counting laser radar was proposed in this paper. Combined with the Poisson statistical model, the method proposed did not need to generate photon counting statistic histogram but used the different distribution feature of signal and noise in the time-domain, which increased the detection probability of signal photons and separated the signal from the noise to recover an accurate depth image of scene in the environment of low signal-to-noise rate. Experimental results demonstrate that the method increases the imaging accuracy by 3-fold at least comparing to the traditional maximum likelihood depth estimation. The method is conducive to the use of laser radar 3D imaging in high background noise environment and could broaden the application range of Lidar.