【作者】 李建阳；

【导师】 常文革；

【作者基本信息】 国防科学技术大学 ， 信息与通信工程， 2006， 硕士

【摘要】 合成孔径雷达(SAR)具有全天时、全天候、远距离、高分辨成像的特点,作为一种主动微波遥感成像系统已经广泛应用于军事侦察、资源勘测、灾害监视等领域。本文针对多波段SAR高分辨成像的应用需求,研究了SAR成像算法、多普勒调频率估计及运动补偿处理以及运动补偿技术的应用三个方面的内容。主要工作概述如下:1、SAR成像算法研究。介绍了高波段SAR和低波段SAR的特点,推导了CS和NCS成像算法,详细分析了成像算法中近似处理所产生的相位误差。针对多波段SAR系统的作用距离、测绘带宽等指标要求,研究了适用于高波段SAR和低波段SAR的成像算法。2、多普勒调频率估计及运动补偿处理研究。推导了高波段SAR和低波段SAR多普勒调频率的数学表达式。介绍了用于估计多普勒调频率的MD、COAA算法。在此基础上采用多波段SAR实测数据,研究了多普勒调频率估计中距离单元的选择、谱分辨率和子孔径长度的选择等问题,提出了一种大测绘带条件下低波段SAR的运动补偿方法。3、运动补偿技术的应用研究。面向多波段SAR系统成像和运动补偿的实际需求,分析了SAR相位历程,提取并分析了高波段SAR和低波段SAR运动补偿前后的相位误差。研究了杂波对空不变相位误差提取的影响。在频域,比较研究了高波段SAR和低波段SAR相位误差的特性。更多还原

【Abstract】 As an active microwave remote-imaging system, synthetic aperture radar (SAR) has applied in the field of military reconnaissance, the field of resource exploration and the filed of disaster watch. SAR has the all-weather, day/night capability to generate a high-resolution representation of the targets over a long range, so it can enhances radar’s information acquisition capability and information awareness ability.This dissertation investigates the problem of synthetic aperture radar imaging algorithms, Doppler rate estimating, Motion Compensation and phase error analyzing. The main contents of the dissertation are described as following.1、SAR imaging algorithm. The differences between high-band SAR and low-band SAR are analyzed. The CS imaging algorithm and NCS imaging algorithm are studied, and we analyze the phase error caused by the approximate of the imaging algorithms. Based on the study of effective swath and effective range in multi-SAR, the imaging algorithm of high-band SAR and low-band SAR are studied.2、Doppler rate estimating and Motion Compensation. The Doppler rates of high-band and low-band SAR are studied. MD and COAA algorithms are analyzed. The criteria of selecting range bin, spectrum resolution and the length of sub-aperture data are studied. The algorithms of motion compensation are proposed in the condition of large and small swath.3、The study of Motion Compensation. Based on the using of imaging and motion compensation in multi-SAR, the phase of SAR is analyzed. The phase errors of SAR are exacted after and before motion compensation. On the basis of phase error, the spectrum of the phase error and the focusing performance of motion compensation are studied.更多还原