基于小波分析的近岸海面风场反演研究

摘要

提出了利用小波变换多尺度分析合成孔径雷达(SAR)影像获取海面风向信息并结合岛礁、船舶等物体背风面形成的风阴影进行风向模糊剔除的近岸海面风场反演算法.与二维傅里叶变换谱分析方法得到的风向反演结果相比,小波分析法可充分发掘不同尺度影像中包含的风向信息,降低了对影像周期性线性纹理特征的依赖,提高了风场反演的分辨率和精度.由岛礁、船舶等形成的风阴影可以用来进行风向模糊剔除,使得反演算法摆脱了对外部风向初始信息的依赖.将反演结果与Seawinds散射计观测风场结果进行的对比分析验证了此方法的正确性.%A new method for wind direction retrieval from synthetic aperture radar (SAR) images based on wavelet analysis is proposed in this study. When using the mothod, wind direction ambiguity can be removed from the wind shadow characteristics formed due to the influence of islands and ships on coastal regions. Compared with the Fourier analysis method, this wavelet analysis method can reduce the dependence on periodical wind streaks and improve the spatial resolution of ocean vector winds. Wind shadows help wind direction ambiguity removal without u-sing wind direction data from other sources. Finally, the retrieval result of the proposed method was validated by the comparison with the Seawinds scatterometer observations.