全极化SAR数据信息提取研究

全极化SAR(Synthetic Aperture Radar)测量的是每一像元的全散射矩阵,可合成包括线性极化、圆极化及椭圆极化在内的多种极化图像。因此与常规的单极化和多极化SAR相比,在雷达目标探测、识别、纹理特征的提取等方面全极化SAR具有很多优点。基于新疆和田地区的SIR-C L波段全极化雷达数据,介绍了极化合成的基本原理和数据处理流程,分析了几种典型地物全极化信号的特点,并在此基础上用监督分类法进行了全极化SAR数据的信息提取。结果表明:全极化SAR数据比单极化和多极化SAR数据具有更高的分类精度,并有效地的提取出地表信息,为利用SAR数据反演地表参数打下了基础。

Study on Extraction of the Ground Information from Quad-polarization Data

SIR\|C is the first spaceborne imaging Radar system with multi\|wavelength and quad\|polarization developed by joint effort of U.S, Italy and Germany. Polarization SAR measures the scattering matrix of each pixel on ground and synthesizes the image at given orientation and ellipticity angle, including linear and elliptical polarization. It has many advantages over single or multi\|polarization SAR in detecting objects, identifying targets and extracting texture. Based on SIR\|C data of Hetian prefecture in Xinjiang of China, this paper presents the basic principle of polarization synthesis and the processing flow of SIR\|C data, analyses the polarization signal of four typical ground objects and makes experiment of extraction of quad\|polarization SAR data using supervised classification method. The experimental result shows that the polarization signal of ground objects vary greatly with the characteristics of geometry and distribution of the objects, on which quad\|polarization SAR data can synthesize certain images to sharpen the contrast of the objects to achieve better classification result and more effectively extract the information. So quad\|polarization has wide applications in survey of land cover and inversly extracting parameters of ground objects.