SAR海面风场反演研究

Research on ocean surface wind field retrievals from SAR

本文对SAR(合成孔径雷达)海面风场反演进行了研究。首先介绍了SAR反演海面风场的物理机制,然后阐述了由雷达后向散射截面反演海面风场的模式函数,随后对最具代表性的CMOD4经验模式函数进行了仿真,得到了海面雷达后向散射系数在不同海面风速、风向、雷达入射角和极化条件下的变化关系。结果表明:海面雷达后向散射截面在不同程度上依赖于风速、风向、入射角和极化方式,这对将CMOD4模式实际应用于SAR海面风场反演有很大的指导作用。

In this paper, retrieval of ocean surface wind field from SAR （synthetic aperture radar） images has been researched. Firstly, the physical mechanism of the retrieval of ocean surface wind field from SAR images is introduced. Secondly, the model functions which are used to retrieve ocean wind field by the radar backscatter cross section are discussed. At last, with CMOD4 empirical model function emulated, the variation distribution of normalized radar cross section of the ocean surface is got respectively under different wind direction, wind velocity, incident angle of radar and polarization condition. The experimental results demonstrate that the normalized radar cross section of the ocean surface is in coordinately dependent on wind direction, wind velocity, incident angle of radar and polarization condition, which will be a guidance in practice to the applications of CMOD4 model for the retrieval of ocean surface wind field from SAR images.