基于频谱分析的SAR图像风场反演算法研究  

Study on SAR wind retrieval algorithm based on spectral analysis

作　　者：陈克海 张金兰[1] 解学通[2] CHEN Kehai;ZHANG Jinlan;XIE Xuetong(School of Mapping and Remote Sensing,Guangdong Polytechnic of Industry and Commerce,Guangzhou 510510,China;School of Geography and Remote Sensing,Guangzhou University,Guangzhou 510006,China)

机构地区：[1]广东工贸职业技术学院测绘遥感信息学院,广州510510 [2]广州大学地理科学与遥感学院,广州510006

出　　处：《测绘科学》2023年第11期153-161,共9页Science of Surveying and Mapping

基　　金：国家自然科学基金项目(41876204);广东工贸职业技术学院科技项目(2023-ZKT-03)

摘　　要：针对SAR图像上的黑白相间的周期间条带蕴含有丰富的海面风场信息,基于频谱分析法提出了一种SAR风场反演算法。在SAR图像功率谱中自适应寻找风条纹具体波数范围,从该波数范围内的方向谱中提取海面3个风向模糊解,并使用圆中数滤波去除风向模糊,得到风向唯一解。风向值确定后,利用地球物理模型求解出风速值。为了测试算法,对GF-3卫星SAR图像进行风场反演实验。实验表明,反演得到的SAR风场与ECMWF数值风场对比,风速绝对偏差均值和均方根误差分别为1.02m/s和1.32m/s,风向绝对偏差均值和均方根误差分别为12.22°和15.60°。算法能有效地从GF-3卫星SAR图像中反演出较高精度的风场,研究结果可为GF-3卫星SAR风场反演技术提供参考。In view of the fact that the black and white periodic streaks on Synthetic-aperture radar(SAR)images contain rich information of wind field over the sea surface,a SAR wind field retrieval algorithm based on spectral analysist is proposed.Firstly,adaptively search for the specific wavenumber range of wind stripes in the synthetic aperture radar(SAR)image power spectrum,then extract three wind direction ambiguities from the directional spectrum within this wavenumber range,and use a circular median filtering to remove wind direction ambiguity,obtaining a unique wind direction solution.After determining the wind direction,use a geophysical model to calculate the wind speed value.In order to test the proposed algorithm,an experiment is used to retrieve wind field from the GF-3 satellite SAR image.The experiment shows that when the retrieved SAR wind field is compared with the ECMWF numerical wind field,the mean absolute deviation(MAE)and root mean square error(RMSE)of wind speed are 1.02 m/s and 1.32 m/s respectively,and the MAE and RMSE of wind direction are 12.22°and 15.66°respectively Thus,the proposed algorithm can effectively retrieve wind field information from GF-3 satellite SAR images.This research results provide a reference for the wind field retrieval technology of GF-3 satellite SAR.

关 键 词：高分三号卫星 合成孔径雷达 风条纹 风场反演 频谱分析 

分 类 号：P236.2[天文地球—摄影测量与遥感]