静止轨道卫星对地观测是获取地表温度、大气参数的重要方式。作为中国第二代静止气象卫星，风云四号卫星A星和B星的组网观测可大幅度扩大气象观测范围和提高数据利用效率。在联合使用之前，需要对两颗星载荷的相同波段的辐射一致性进行探索。本文提出了一种校正静止轨道卫星观测角度效应和光谱响应函数差异的方法，以对地观测热红外波段数据为例，在敦煌定标场、呼伦贝尔草原、巢湖、南海四个研究区开展了风云四号A/B卫星三个热红外波段（中心波长：8.5μm、10.8μm、12.0μm）辐射一致性研究。基于消除了时空差异、观测角度差异和光谱响应函数差异数据的分析结果表明，风云四号A星和B星的三个热红外波段观测亮温间具有很强的正相关性，亮温的误差较小，辐射一致性较好，但不同热红外波段之间的辐射一致性略有不同。第二热红外波段亮温一致性优于第三波段，第三波段表现优于第一波段。三个波段的亮温均方根误差处于0.28～1.51K，偏差处于-1.13～0.85K。第二、三波段的亮温差呈现明显的正偏态分布，第一波段的亮温差呈现负偏态分布。针对本文提出的校正方法，比较校正前后的统计结果，发现校正方法适用，且角度效应的校正方法能够明显降低两颗卫星热红外波段的亮温差异。两颗卫星热红外辐射一致性还受地类影响，在不同的地表类型下，三个波段的一致性表现略有差异。本文的研究成果可为风云四号A/B卫星热红外数据的联合使用提供重要依据。

Objective: The observation of geostationary orbit satellite, with the characteristics of wide range, high frequency and fixed point observation, provides an important way to obtain land surface and atmospheric parameters and can monitor the change of land surface temperature over long time series. As the second generation of China’s geostationary meteorological satellites, Fengyun-4 A and B satellites constellation observation greatly expand the scope of meteorological observation and improve data utilization efficiency. Before the joint use of the two satellites’ data, the radiometric consistency between the same bands observation of the two satellites needs to be explored. Method: Taking the thermal infrared band data as an example, the radiometric consistency between three thermal infrared bands (centered at 8.5μm, 10.8μm and 12.0μm) of Fengyun-4 A/B satellites was studied in four experimental areas: Dunhuang calibration field, Hulunbuir Grassland, Chaohu Lake, and South China Sea. The heterogeneity of the Dunhuang calibration field and the Hulunbuir Grassland study area was evaluated firstly. A method was then proposed to correct the angular effects and spectral response function differences in observation from geostationary orbit satellites. This method corrected the angular effects by establishing empirical relationships between simulated radiance data at different viewing angles and eliminated spectral response function differences by correcting the brightness temperature and radiance on basis of the lookup tables. Finally, this method was used to correct the thermal infrared data of the two satellites at the same observation time, and the brightness temperature after correction were compared to analyze the radiometric consistency of the corresponding thermal infrared bands. Results: Based on the data analysis, after removing the difference of space-time, observation angle and spectral response function of two satellites, the results show a strong positive correlation between the brightness temperatures of the three thermal infrared bands on Fengyun-4A and Fengyun-4B satellites. The brightness temperature errors are small, indicating good radiometric consistency. However, there is still a slight variation in brightness temperature among those different thermal infrared bands. The consistency of brightness temperature of the second thermal infrared band is better than that of the third band, and the third band performs better than the first band. The root mean square errors of brightness temperatures for the three bands range from 0.28 to 1.51 K, with deviations between -1.13 and 0.85 K. The brightness temperature deviations in the second and third bands exhibit a noticeable positive skewness, while the deviations in the first band shows a negative skewness. Conclusion: By comparing the brightness temperature data before and after correction, it is not difficult to find that the method proposed in this paper has good applicability for the study of radiometric consistency in thermal infrared band of geostationary orbit satellite. The results show that the radiometric consistency of thermal infrared radiation between the two satellites is generally good although it might be influenced by land cover types. The findings in this paper provides important guidance for the joint utilization of thermal infrared data from Fengyun-4A and Fengyun-4B satellites.