基于激光雷达和大气透射仪的机场能见度联合探测关键技术

As fast development of aviation, aeronautical meteorology has been regarded as particularly important. As one of the most important quantities in meteorology, atmosphere visibility plays important roles on the flight safety. For a pilot in flight the slant-range visibility is more crucial than the horizontal visibility. A lidar is known as the most efficient equipment for the determination of the slant-range visibility of the atmosphere. We focus our work on the retrieval of the aerosol extinction coefficients using the multiple-scattering lidar equation. The analytical expression of the slant-range visibility will be given in terms of the atmosphere extinction coefficient, the atmosphere brightness and the brightness of the background. On the other hand, a transmissometer has been used as a visibility meter for measuring the horizontal visibility at airports around the world. However, several transmissometers using a LED and a laser as the light source are present. We plan to investigate the effects of spectrum of the transmissometer light source on light transmittance. The light transmittance is important for deriving the horizontal visibility using the transmissometer. Additionally, we plan to perform the detections of the horizontal visibility and the slant-range visibility using several transmissometers and the lidar, previously developed by us. At the end we will propose the algorithm for simultaneously retrieving the horizontal visibility and the slant-range visibility with high accuracy. Our work is important for promoting technologies of the visibility measurement, and is useful for developing the lidar as a slant-range visibility meter used in airports in China. It is particularly important for the flight safety in civil aviation.

我国航空运输业发展迅速，航空气象的研究变得重要和迫切。作为航空气象领域的重要参数之一，能见度对航空运输安全有重要影响。对于飞行员的实际飞行来说，斜程能见度比水平能见度更具参考意义。然而，目前机场安装的能见度测量装备仅能探测水平能见度。本项目一方面针对激光雷达斜程能见度探测中的关键问题，研究多次散射条件下激光雷达消光系数的反演，建立斜程能见度模型，另一方面针对多种光源大气透射仪水平能见度探测中的关键问题，研究光谱特性对光透过率的影响，建立水平能见度模型。在实验中，使用自主研发的多个水平能见度探测设备和激光雷达进行实际的能见度探测，修正能见度，提出高精度能见度反演方法，实现激光雷达和大气透射仪的机场能见度联合探测。项目研究成果将推动激光雷达能见度仪的民航准入进程，填补我国机场斜程能见度研究领域的空白，同时，也为研发具有我国自主知识产权的大气透射仪提供理论和实践依据，从而提高机场气象保障水平。

本项目按计划完成了申请书中提出的研究内容和研究目标。一方面，以地基激光雷达和星载激光雷达作为斜程能见度探测手段，围绕机场斜程能见度反演方法开展研究工作，研究内容包括考虑多次散射的激光雷达消光系数反演、斜程能见度影响因素分析、斜程能见度建模。另一方面，以大气透射仪作为水平能见度探测手段，针对商用的以LED为光源的大气透射仪和激光大气透射仪所涉及的基本理论问题，研究光频谱特性和偏振特性对光透过率的影响、建立水平能见度模型。在实验方面，在可控的大气环境中，采用大气透射仪和自主研发的激光雷达，实施水平能见度和斜程能见度测量，结合理论研究成果，提出用于我国民航机场的能见度修正与高精度能见度反演方法。项目共发表论文14篇，其中SCI或EI检索论文10篇，获得软件著作权2项。研究成果将为激光雷达能见度仪进入民航应用提供重要理论及实践依据，推动激光雷达能见度仪的民航准入进程，填补我国机场斜程能见度研究领域的空白。同时，也为改善现有的大气透射仪水平能见度反演算法，研发具有我国自主知识产权的大气透射仪提供理论和实践依据。