中国海洋大学学报（自然科学版）2024，Vol.54Issue(1)：144-155,12.DOI:10.16441/j.cnki.hdxb.20220442
基于准线性近似方法的SAR图像海浪参数反演研究
Research on Ocean Wave Retrieval from SAR Image Based on the Quasi-Linear Approximation Method
摘要
Abstract
Synthetic aperture radar(SAR)images of ocean wave contain not only speckle noise,but al-so textures of other atmospheric and oceanic phenomena(such as wind streaks).The existence of these non-wave noises and textures will affect the accuracy of ocean wave retrieve based on SAR images,espe-cially in the low wave number domain of the retrieved wave spectrum.In this paper,according to the feature of speckle noise changing rapidly with time and the feature of non-wave texture phenomenon changing slowly with time,a method of suppressing speckle noise and large-scale non-wave texture is proposed based on cross spectrum.Then combined with the quasi-linear mapping relation between SAR image spectrum and ocean wave spectrum,the wave parameters were retrieved.In the inversion process,firstly,the retrieve ability of the quasi-linear approximation method under different sea states is analyzed by simulation.The results show that the azimuth cutoff effect caused by wind wave will sig-nificantly affect the retrieve accuracy,so the retrieve accuracy of this method is higher at low wind speed.By comparing the retrieved results of wave mode SAR data acquired by Sentinel-1 in 2020 with reanalysis data provided by the European Centre for Medium-Range Weather Forecasts(ECMWF),it is found that the retrieved result of significant wave height in high sea state is obviously low,and there is a significant correlation between the inversion error and wind speed and azimuth cutoff wavelength.In order to improve the retrieve accuracy of significant wave height,the empirical correction function model between the inversion error of SAR significant wave height and wind speed and azimuth cutoff wave-length is further presented.The results show that the retrieved results of SAR significant wave height modified by this model is in good agreement with the ECMWF data and buoy data.关键词
海浪/合成孔径雷达/准线性近似法/有效波高/非海浪纹理Key words
ocean wave/synthetic aperture radar(SAR)/quasi linear approximation method/signifi-cant wave height/non-wave texture分类
信息技术与安全科学引用本文复制引用
袁超文,张彦敏,姜文正,王运华..基于准线性近似方法的SAR图像海浪参数反演研究[J].中国海洋大学学报（自然科学版）,2024,54(1):144-155,12.基金项目
国家自然科学基金项目(41976167,52101393) （41976167,52101393）
山东省自然科学基金项目(ZR2021MD023,ZR2021QD001)资助 Supported by the National Natural Science Foundation of China(41976167,52101393) （ZR2021MD023,ZR2021QD001）
the Natural Science Foundation of Shandong Province(ZR2021MD023,ZR2021QD001) （ZR2021MD023,ZR2021QD001）
