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等效视图数是极化合成孔径雷达图像信息处理过程中的关键参数之一.首先提出了基于子矩阵对数累积量的极化合成孔径雷达图像等效视图数估计的最大似然估计方法及其子矩阵联合最大似然估计方法.所提估计方法是基于表征多视极化雷达图像数据的协方差矩阵及其子矩阵的对数累积量建立,打破了原有方法只能应用于图像数据符合高斯相干斑模型而不能应用于图像数据符合多变量乘积相干斑模型的限制,拓展了等效视图数估计方法的适用范围.然后给出了不同阶子矩阵对数累积量估计方法对估计精度的影响,并与已有方法和Cramér-Rao限进行了对比,给出了最佳的最大似然估计方案,同时针对估计方法对样本数目的依赖,给出了对数累积量估计的修正算法.最后对提出的估计方法进行了理论仿真和实测数据验证,结果表明了等效视图数估计新方法的正确性和有效性,特别适用于相干斑的乘积数据模型,提高了极化合成孔径雷达图像模型参数估计的快速性和准确性.
The equivalent view number is one of the key parameters in Polarimetric SAR image information processing.Firstly, the maximum likelihood estimation method based on the logarithm cumulant of sub-matrix cumulant is proposed. And its sub-matrix joint maximum likelihood estimation method.The proposed method is based on establishing the logarithm cumulant of the covariance matrix and its sub-matrix of multi-view polarimetric radar imaging data, breaking the existing method can only be applied to image data Which is consistent with the Gaussian speckle model and can not be applied to the image data conforming to the multivariate product speckle model and expands the scope of the equivalent number of views estimation method.And then gives the estimation of logarithmic cumulant of different orders matrix estimation accuracy , And compared with the existing methods and the Cramér-Rao limit, the optimal maximum likelihood estimation scheme is given. At the same time, aiming at the dependence of the estimation method on the number of samples, a modified algorithm of logarithmic cumulant estimation Finally, the proposed estimation method is verified by theoretical simulation and measured data, and the results show that the new method of equivalent view number estimation is correct and effective It is especially suitable for the multiplicative data model of coherent speckle to improve the speed and accuracy of parameter estimation of Polarimetric SAR image model.