基于X波段雷达图像估计有效波高的改进方法

摘要

This paper proposes the rotated empirical orthogonal function (REOF) method to restore the wave height on the basis of restoring the significant wave height (SWH) by empirical orthogonal function (EOF).REOF method overcomes the defects of EOF analysis on the mode decomposition.This paper references the linear relationship between SWH and the square root of signal noise ratio of radar echo and establishes a linear relationship between the Shannon entropy of principal components and SWH using REOF.Using the X-band radar image time series in Bohai Bay,SWH is obtained.The correlation coefficient between the SWH of the buoy and that obtained by the improved algorithm is 0.86,and it is better than that obtained by EOF analysis,which is only 0.82.The results show that the algorithm proposed in this paper can extract the SWH effectively,and the effect is better than EOF analysis.%本文在利用经验正交函数(EOF)恢复有效波高(SWH)的基础上,克服EOF分析在模态分解时的缺陷,提出旋转经验正交函数(REOF)方法恢复波高.借鉴SWH与雷达回波强度信噪比的平方根成线性的关系,建立了SWH和REOF分析得到的主成分的Shannon熵之间的线性关系.根据渤海湾X波段雷达图像时间序列,利用REOF分析获取了SWH.浮标采集的SWH与该改进算法获取的SWH之间的相关系数为0.86,优于浮标和EOF分析恢复的SWH之间的相关系数0.82.实验结果表明,本文中提出的算法可以有效的提取SWH,且比EOF分析提取SWH的效果更好.