基于空域滤波的二维全极化散射中心快速提取  

Fast Extraction of 2D Full Polarization Scattering Centers Based on Spatial Filtering

作　　者：张肖[1] 周建江[1] 汪飞[1] 

机构地区：[1]南京航空航天大学电子信息工程学院,江苏南京210016

出　　处：《航空学报》2014年第9期2530-2539,共10页Acta Aeronautica et Astronautica Sinica

基　　金：国家自然科学基金(61371170);江苏高校优势学科建设工程~~

摘　　要：在全极化逆合成孔径雷达(ISAR)体制下,二维相干极化几何绕射(CP-GTD)模型能够精确描述雷达目标高频电磁极化散射特性。针对CP-GTD模型,提出了一种基于空域滤波的二维全极化散射中心参数快速提取方法。该方法利用空域滤波将二维全极化散射中心参数提取问题分解为多个一维全极化散射中心提取问题,进而利用一维旋转不变技术(1D-ESPRIT)分步对全极化散射中心各维参数进行联合估计,最后利用最小二乘方法获得相干极化散射矩阵的估计。此外,采用这样的分步估计过程,可以实现二维参数的自动配对。复杂度分析和仿真实验表明:该方法不仅能够显著降低运算量,并且还能获得较好的估计精度,可以有效地用于目标全极化散射中心提取。Under the full polarization inverse synthetic aperture rador（ISAR）imaging radar system,the high-frequency electromagnetic scattering of the radar target can be described accurately by a two-dimensional model derived from the coherent polarization and geometrical theory of diffraction（CP-GTD）.For the two-dimensional CP-GTD model,a fast method based on spatial filtering is proposed to extract parameters of two-dimensional full polarization scattering centers.The proposed method utilizes spatial filtering process to decompose two-dimensional full polarization scattering centers extraction into several times of one-dimensional scattering centers extraction,and then the one-dimensional rotational invariance technique（1DESPRIT）is employed to jointly estimate each dimensional parameter of full polarization scattering centers step by step.Finally,polarimetric scattering matrices are estimated via the least square method.Furthermore,with such a step-by-step estimating process,two-dimensional parameters can be automatically paired.Complexity analysis and simulation results show that the proposed method not only greatly reduces the computational burden,but also keeps high accuracy of parameter estimation,and it is proved to be effective in full polarization scattering center extraction of target.

关 键 词：散射中心 全极化 几何绕射模型 空域滤波 旋转不变技术 

分 类 号：V443[航空宇航科学与技术—飞行器设计] TN957[电子电信—信号与信息处理]