一种基于目标散射鉴别的POLSAR图像地物无监督分类新方法  

A New Scattering-Identification Based Unsupervised Terrain Classification for POLSAR Image

作　　者：陈强[1] 蒋咏梅[1] 陆军[1] 匡纲要[1] 

机构地区：[1]国防科技大学电子科学与工程学院,湖南长沙410073

出　　处：《电子学报》2011年第3期613-618,共6页Acta Electronica Sinica

摘　　要：提出了一种基于目标散射鉴别的POLSAR图像地物无监督分类新方法.该方法首先利用极化散射熵将POLSAR图像地物粗分为高散射随机性、中散射随机性和低散射随机性三种情形;然后提取球面散射、偶次散射和体散射相似性参数将上述三种情形细分为十种;在上述散射分类的基础上,采用新定义的两类目标极化差异度量对地物进行类别迭代调整.由于球面散射、偶次散射和体散射为地物固有散射,采用它们的相似性参数进行散射分类,使散射分类结果更符合实际地物散射情况;根据散射相似性参数大小确定散射类别,克服了现有散射分类人工确定类别边界带来的不足;新定义的两类目标极化差异度量运算简便,克服了Wishart距离度量运算偏大的不足.实测极化数据的实验结果验证了新方法的有效性.a method for unsupervised terrain classification of POLSAR imagery is proposed.At first,the polarimetric entropy is utilized to divide terrain scattering into three cases,i.e.high entropy,medium entropy and low entropy.Then surface scattering,double scattering and volume scattering similarities are computed for initially classifying POLSAR image into ten classes.Finally,the initial classification map defined training sets for reclassification based on a new defined parameter to measure the deference degree between two targets.As surface scattering,double scattering and volume scattering are the inherent characteristics of terrain physical scattering,the scattering classified results are more accord with real terrain scattering;the automatic determination of scattering type with scattering similarity overcomes the deficiency of the present scattering classification;the simple computation of the deference degree speeds up the above reclassification.The experiment results with real POLSAR image demonstrate the validity of the proposed method.

关 键 词：散射相似性 无监督地物分类 差异度量 

分 类 号：TN957[电子电信—信号与信息处理]