摘要
极化合成孔径雷达(synthetic aperture radar,SAR)包含了丰富的目标散射信息,已被广泛用于海上船只检测.文中将机器视觉中基于残差谱视觉显著性区域提取方法扩展到极化SAR船只检测.首先,全面分析SAR极化特征的船海区分能力,利用5景RADARSAT-2全极化数据,对比45种极化特征的船海欧式距离、巴氏距离和对比度,筛选出16个船海对比度大于20 dB的极化特征;其次,挑选出适用于残差谱显著性区域提取船只检测的极化特征组合,通过特征间互信息、图像对数谱特性分析,确定利用相干矩阵的三个幅度极化特征组合成RGB图像进行船只检测;最后,将本文方法与基于恒虚警率的方法比较.在测试图像中,传统方法的品质因数小于0.9,本文方法的品质因数为0.95.本文方法能够很好地抑制虚警,同时还可直接提取出目标的轮廓等几何信息,具有一定的应用前景.
Polarimetric synthetic aperture radar(SAR)has been widely used in maritime ship detection due to its abundant target scattering information.In this paper,the visual saliency region extraction method based on residual spectrum in machine vision is extended to Pol-SAR ship detection.Firstly,the ship discrimination ability of SAR polarimetric features is analyzed,and 5 RADARSAT-2 full-polarization data are used to compare with the Euclidean distance,Bhattacharyya distance and ship-sea contrast of 45 polarization features,then,16 polarimetric features with the contrast greater than 20 dB are selected.Secondly,the combination of polarimetric features suitable for the saliency regional method of residual spectral is picked out.Based on the analysis of the mutual information of features and the logarithmic spectrum characteristics of the image,three amplitude features of the coherent matrix T are selected and combined into RGB images for ship detection.Finally,the method presented is compared with the traditional constant false-alarm rate(CFAR)method.The figure of merit of the method in this paper is 0.95 while the value of traditional CFAR method is less than 0.9.The result shows that the false alarm can be restrained well,and geometric information such as the contour of target can be directly extracted,the method has certain application prospect.
作者
刘根旺
张杰
张晰
孟俊敏
LIU Genwang;ZHANG Jie;ZHANG Xi;MENG Junmin(First Institute of Oceanography,Ministry of Natural Resources,Ocean Telemetry Technology Innovation Center,Qingdao 266061,China)
出处
《电波科学学报》
EI
CSCD
北大核心
2019年第6期751-760,共10页
Chinese Journal of Radio Science
基金
国家重点研发计划(2017YFC1405201)
海洋公益性行业科研专项(201505002)
关键词
极化合成孔径雷达
船只目标
极化特征筛选
互信息分析
显著性检测
polarimetric synthetic aperture radar
ship target
polarimetric features selection
mutual information analysis
logarithmic amplitude spectrum
saliency detection
