一种基于曲线SAR的三维目标特征提取与自聚焦新算法  

A Novel Autofocus and 3-D Target Feature Extraction Algorithm for Curvilinear SAR

作　　者：吴仁彪[1] 苏志刚[1] 刘家学[1] 刘杰[1] 

机构地区：[1]中国民用航空学院通信与信息处理研究所,天津300300

出　　处：《遥感学报》2002年第6期490-495,共6页NATIONAL REMOTE SENSING BULLETIN

基　　金：国家自然科学基金项目(69902009);国家863高技术计划项目(863-308-19-01-(3))资助课题。

摘　　要：曲线合成孔径雷达（Curvilinear Synthetic Aperture　Radar,简称曲线 SAR）是一种新的三维成像模式。通过让载机作曲线飞行,曲线SAR系统能同时在方位维和高度维形成大的合成孔径。本文提出一种曲线SAR的三维目标特征提取和自聚焦新方法。新方法是建立在一种灵活的接收数据模型之上的参数化的新方法。仿真实验证明了所提方法的有效性。By transmitting signals with large bandwidth and utilizing the relative motion between the radar and the objects to be imaged, synthetic aperture radar(SAR) can produce high-resolution images of targets or scenes of interest. Now, SAR imaging technology has been widely used in many military and civilian applications, such as battlefield awareness, environment monitoring,and city planning. Today, over thirty SAR systems have been put into operation and more are being built around the world. However,most of them can only produce two-dimensional(2-D)SAR images. In practice, 3-D SAR images and 3-D target feature extraction are needed for many applications. The 3-D features of a target scatterer include the radar cross-section (RCS) ,the 2-D location (range and cross-range) and the height(the third dimensional parameter)of the scatterer.Very few papers have discussed the 3-D target feature extraction problem. A popular approach to extract the 3-D target features is interferometric SAR(IFSAR) , which uses a pair of vertically displaced antennas to obtain coherent and parallel measurement apertures. IFSAR can be used to measure the height but has no resolution capability along the height dimension since it only provides two vertical parallel apertures. Hence IFSAR is only a 2.5-D imaging system. Moreover, in IFSAR, the height measurement involves the troublesome phase unwrapping procedure. Recently, Knaell proposed a new idea for the extraction of 3-D target features, which is based on curvilinear SAR(CLSAR) . Unlike the conventional SAR or IFSAR, whose flight trajectory is a straight line, the flight path of a CLSAR system is curve-shaped. CLSAR can be used to form synthetic apertures both in the azimuth and in the height dimensions. Hence CLSAR has resolution capability in the height dimension and the height ambiguity problem encountered in IFSAR is avoided.There are two challenging issues associated with CLSAR. First, the flight path of CLSAR cannot be controlled or measured accurately and the autofocus task here is

关 键 词：合成孔径雷达 曲线合成孔径雷达 运动补偿 三维特征 提取 数据模型 自聚焦算法 

分 类 号：TP751.1[自动化与计算机技术—检测技术与自动化装置] TP72[自动化与计算机技术—控制科学与工程]