ISAR运动补偿聚焦方法的改进

Improvements of Autofocusing Techniques for ISAR Motion Compensation

运动补偿是ＩＳＡＲ成像中的关键。通常分粗、精补偿两步进行。粗补偿是回波包络的粗略对齐，而精补偿则是寻找一个相位参考点进行回波相位的精细调整，通常称为聚焦。本文提出了两种改进的聚焦法，即加权多特显点综合法（ＷＭＳＡ）和改进的散射重心跟踪法（ＩＳＣＴ），并与孤立点法（ＤＳＡ）作了分析比较。最后利用雷达外场实测飞机数据比较了它们的成像结果。

Motion compensation is the key of ISAR imaging,and is usually carried out in two steps. First,compensate the time delay of complex envelope ,which is a roughly alignment. Second,search for a reference point to precisely adjust the initial phase,which is usually referred to as autofocusing. The paper presents two improved autofocusing techniques called weighted multiple scatterer algorithrn (WMSA)and improved scatter centroid tracking (ISCT). They are analyzed and compared with the dominant scatterer algorithm (DSA). Finally ,the outdoor measured ISAR data of aircrafts are processed and the imaging results are compared with each other.