The noise scale factor (NSF) is useful in calculating the random errors of lidar signals. A new method is proposed for estimating the NSF of lidar systems. Instead of measuring the solar background in the traditional method that demands special experiments or additional devices, the new method utilizes the molecular backscattered signal fragments of routinely observed lidar profiles to extract the light intensities and shot noises. Based on a 355 nm lidar system, experiments with the two methods have been carried out. The NSF calculated with the new method is 0.6473, very close to the value resulted from the traditional method, which is 0.6496. The experiments indicate that the new method is feasible and accurate. An example of calculating the random errors and signal to noise ratios (SNR) of lidar signals by using NSF is presented. Compared with the results calculated from multiple lidar profiles, the method using NSF eliminates the influence of aerosols and clouds.

中文翻译：

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一种估计激光雷达观测中的噪声比例因子 (NSF) 和随机误差的新方法

噪声比例因子 (NSF) 可用于计算激光雷达信号的随机误差。提出了一种估计激光雷达系统 NSF 的新方法。与需要特殊实验或额外设备的传统方法测量太阳背景不同，新方法利用常规观察到的激光雷达轮廓的分子背向散射信号片段来提取光强度和散粒噪声。基于 355 nm 激光雷达系统，对这两种方法进行了实验。新方法计算的NSF为0.6473，非常接近传统方法的0.6496。实验表明，新方法可行且准确。介绍了使用 NSF 计算激光雷达信号的随机误差和信噪比 (SNR) 的示例。