干涉图幅度统计分布模型族及其参数估计

Interferometric Magnitude Modeling and Parameter Estimation

提出了新的干涉图幅度分布模型族及对应的参数估计器.首先,在乘积模型框架下,以复Wishart分布为基础,通过引入场景环境分类的思想,利用具备真实地物RCS分量精确建模能力的逆方根Gamma分布和广义逆Gauss方根分布,推导建立了理论完善的新的干涉图幅度分布模型族:E-Gamma分布、E-G0分布和E-G分布,解决了均匀度变化下的广泛区域对应的干涉图幅度数据的精确建模问题,实现了单通道SAR图像建模理论到多通道SAR干涉图幅度建模的拓展与统一;其次,基于Mellin变换导出了各新分布模型的参数估计器:E-Gamma_MoLC、E-G0_MoLC和E-G_MoLC,新估计器能够快速、准确地迭代出各分布参数的估计值.以KL度量、MSE度量和K-S检验作为定量评估准则,对星载多通道SAR实测数据对应的干涉图进行实验,结果证明了所提模型族及对应参数估计器的有效性.

The paper proposes a group of new distributions for interferometric magnitude and their corresponding parameter estimators.Firstly,under the frame of multiplicative model,based on the complex Wishart distribution,and bringing in the theory of clutter classification brought forward by Frery et al., the new intefferometric magnitude＇ s statistical models are deduced according to utilizing the reciprocal of a square root of Gamma and the square root of generalized inverse Gaussian law. The group of new mod- els can Precisely model the interferometric magnitude corresponding to different clutter areas with broad degrees of homogeneity, and they achieve the unification of the statistical distributions for single-channel SAR images and multi-channel SAR interferometric magnitude. Secondly, The new models＇ estimators are acquired based on the MeUin Iransform which can estimate the contained parameters quickly and accttrately, guaranteeing the new distributions＇ fitting precision. According to the experiments performed on the real spacebome SAR image, using the KuUback-Leibler （KL） distance,mean square error （MSE） and Kolmogomv-Smimov （KS） test as similarity measurements, the experimental results show the effectiveness of the proposed models and estimators.