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2018年5月，高分五号卫星成功发射，其搭载的AIUS（Atmospheric Infrared Ultraspectral Sounder）传感器是我国研发的第一个红外波段具有甚高光谱分辨率的掩星探测仪，为大气分布状态的研究提供了强有力的数据支持。气温是表征大气热力状态的重要参数，其分布状态直接影响地-气系统长波辐射和太阳短波辐射的相互作用，进而对全球辐射能量的收支平衡产生影响。采用高光谱数据直接进行气温反演的数据量较大、存储不便，并且不同波谱信息之间存在相关性，因此需要进行通道选择。考虑到实际气温反演精度受干扰成分的影响较大，致使反演精度较低，本文将基于信息熵的通道选择算法与目标成分及干扰成分的敏感性分析相结合开展试验完成AIUS掩星观测数据的通道选择，为后期AIUS的温度反演奠定基础。首先，基于RFM(Reference Forward Model)正向辐射传输模型进行目标成分及干扰成分的敏感性分析，探究通道选择的可行性及进行初步的通道选择；之后，基于信息熵的理论进行通道选取，并对结果进行分析讨论；最终依据通道选取结果，结合最优化算法进行温度反演效果验证。研究表明：掩星观测对气温变化具有较高的敏感性，该通道选择方法在掩星观测模式下是可行的；随通道数目的增加，信息量大体呈对数型增加，在通道个数为1000时接近饱和；在保证运算效率条件下，选用AIUS的100个通道进行温度反演，可基本满足精度需求。
Atmospheric Ultraspectral Sounder of gaofen 5 satellite was successfully launched in May 2018. AIUS (Atmospheric Ultraspectral Sounder) sensor is the first Infrared band occultation observation sensor with very high resolution developed in China, providing strong data support for the study of Atmospheric distribution state. Air temperature is an important parameter that characterizes the thermodynamic state of the atmosphere. Its distribution state directly affects the interaction between the long-wave radiation and the short-wave radiation of the earth-atmosphere system, and then affects the global balance of radiation energy. The direct inversion of temperature using hyperspectral data which is large, inconvenient to store, and there is correlation between different spectral information, so channel selection is required. Considering that the actual air temperature inversion accuracy is greatly affected by interfering components, resulting in a low inversion accuracy, this paper combined the channel selection algorithm based on information entropy with the sensitivity analysis of target components and interfering components to carry out experiments to complete the channel selection of AIUS occultation observation data, laying a foundation for later AIUS temperature inversion. Firstly, based on the RFM model, the sensitivity analysis of target components and interference components was conducted to explore the feasibility of channel selection and conduct preliminary channel selection. Then, the channel selection is carried out based on the theory of information entropy, and the results are analyzed and discussed. Finally, based on the channel selection results, the temperature inversion effect is verified by optimization algorithm. Studies have shown that occultation observation is highly sensitive to temperature changes, and the channel selection is feasible in occultation observation mode. With the increase of the number of channels, the amount of information increases logarithmically, and is close to saturation when the number of channels is 1000. In order to improve the operational efficiency, 100 channels of AIUS are selected for temperature inversion, which can basically meet the precision requirements.