【作者】 汪玲；

【导师】 朱兆达；

【作者基本信息】 南京航空航天大学 ， 通信与信息系统， 2003， 硕士

【摘要】 逆合成孔径雷达(ISAR)对非合作目标成像时，运动补偿是整个成像信号处理中的一个关键。目标和雷达的相对运动可以分解为目标上的参考点相对于雷达的平动以及目标绕参考点的转动。其中只有转动分量对成像有贡献，平动分量对成像无用而有害。它对ISAR成像的影响有两个方面：一是使相邻的一维距离像在距离向错开，无法进行方位向分辨。二是引入了附加的相位分量，在方位向造成散焦。运动补偿就是在成像前消除掉平动在这两方面的影响。运动补偿通常分为两步：距离对准和相位补偿。本文结合ISAR实测数据，研究了ISAR运动补偿算法。 本文的第一章为绪论，简要介绍了ISAR的基本概念，发展历史和现状，以及本文的主要内容。 第二章在给出ISAR成像基本原理的基础上，详细阐述了ISAR运动补偿问题。 第三章详细阐述了目前主要的几种距离对准方法的原理，进一步地分析了它们的性能。然后文中给出了具体实现这些方法的步骤，以及在这些方法的基础上，进一步提高对准精度可采取的措施。最后给出了采用这些方法对实测数据的处理结果。 第四章在阐述了现有的主要几种相位补偿方法的基础上，把秩一相位估计(ROPE)算法应用于ISAR相位补偿，给出了具体的使用方法，并结合实测数据的处理结果，同其它方法的性能作了比较。实际表明，ROPE是一种有效的相位补偿方法，且实现简单，具有较佳的补偿性能，优于原有的一些相位补偿方法。 本文的结束语对全文的工作进行了总结，指出了有待进一步研究的问题。更多还原

【Abstract】 The objects of ISAR imaging are usually non-cooperative targets. So the motion compensation is a key technique in ISAR. The motion of a moving target relative to the radar can be decomposed into two parts:the translational motion of a reference point in the target and the rotational motion of others about the reference point. Only the latter is useful to the imaging. The former does not contribute to the imaging and is harmful. It influences ISAR imaging in two aspects:First,it causes the range misalignment of the range profiles which makes the processing in cross-range impossible. Second,it introduces an additive phase component which induces defocus in cross-range. Therefore,the task of the motion compensation is to remove out the translational motion before imaging. It is usually divided into two steps:range alignment and phase compensation. In this article,we have a deep study on the ISAR motion compensation algorithms by combining with the ISAR real data which aims for a better-quality image of ISAR.In the preface to this dissertation,the basic idea the development of the ISAR are introduced briefly. And the main contribution of this dissertation is summarized here.Chapter 2 exposits the problem of the ISAR motion compensation in detail after the principle of the ISAR imaging is described.In chapter 3 the principles of the main range alignment methods at the present time are detailed and further the performance of these methods is analyzed. Subsequently the concrete implementation steps of them and some measurements for further improving the alignment accuracy are presented. Finally,the alignment results of the ISAR real data achieved by these methods are shown.In chapter 4,firstly a detailed exposition of the current main methods of ISAR. phase compensation is presented. Secondly we apply the ROPE algorithm to ISAR phase compensation and illustrate how to use it. Finally,by combining with the ISAR real data,the performance of the ROPE is compared with the other methods. The fact demonstrates that ROPE is an effective method for phase compensation and accomplished simply. It has good compensation performance superior to some existing methods. In the end,conclusions and possible future work are explained.更多还原