机载ISAR舰船侧视和俯视成像时间段选择  

Interval Selections for Side-view or Top-view Imaging of Ship Targets with Airborne ISAR

作　　者：汪玲[1] 朱兆达[1] 朱岱寅[1] 

机构地区：[1]南京航空航天大学信息科学与技术学院,南京210016

出　　处：《电子与信息学报》2008年第12期2835-2839,共5页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(60502030);航空科学基金(05D52027)资助课题

摘　　要：舰船目标成像是ISAR技术研究领域的热点,其关键是获得具有较高应用价值的舰船侧视图和俯视图。该文通过对数据分段短时成像,估计舰船在一系列子图像中的多普勒频率展宽和船体中心线斜率,获得雷达与舰船之间合成有效转动矢量和垂直转动分量随时间的变化。继而根据这两个转动矢量,判断海面环境情况和舰船摇摆强弱,对成像情况进行细分,确定侧视图和俯视图成像时刻,同时以该时刻为中心,通过使图像熵最小,获得最佳成像积累时间。仿真和机载ISAR实测数据处理验证了该时间段选择方法的有效性和实用性,可在未知海情下获得舰船的侧视图或者俯视图,有利于舰船目标的进一步识别。The imaging of ship targets is an active area in ISAR research field. Its key is to obtain the valuable side view and top view ship images. In this paper, by measuring the Doppler spreads and the centerline slopes of the ship from a sequence of sub-images generated with successive short time data, the variations of the resultant effective rotation vector and its vertical component are estimated. Subsequently, the sea state and the rock intensity of the ship are evaluated according to the two estimated rotation vectors, and the imaging processing is separate into several different cases. In each case, the imaging instants for ship side view and top view are determined. At the same time, the optimal duration centered with the chosen instant is searched by minimizing the image entropy. Simulated data and real data verify the effectiveness and practicability of the method. The ship top view or side view image can be obtained under unknown sea state, which much benefits the subsequent ship identification.

关 键 词：逆合成孔径雷达(ISAR) 舰船成像 时间段选择 侧视 俯视 

分 类 号：TN959.72[电子电信—信号与信息处理]