【作者】 赵志伟；

【导师】 杨汝良；

【作者基本信息】 中国科学院研究生院（电子学研究所） ， 通信与信息系统， 2007， 博士

【摘要】 星载扫描干涉合成孔径雷达(Scan-InSAR)是将扫描合成孔径雷达(ScanSAR)的宽测绘带特性与干涉合成孔径雷达(InSAR)的高程测量能力相结合的一种宽幅高程测量技术。利用扫描干涉合成孔径雷达的处理结果可获得宽测绘带内的高程信息，有利于快速实现全球高程测绘；也可在较短时间内得到同一区域的地表变化信息。本文对扫描干涉合成孔径雷达的系统参数及相关的信号处理方法进行了深入研究。论文的主要工作及创新性贡献有：(1)研究了常用的ScanSAR成像算法，包括SPECAN算法、全孔径算法和ECS算法。分析了各算法的相位保持特性；深入研究了用于ScanSAR成像的ECS算法，推导了成像过程中信号相位的变化，分析了距离scaling函数对成像结果的影响，分析了该算法的图像伸缩特性；对各种算法的特点和适用条件进行了对比。(2)研究了干涉SAR数据处理方法。提出了一种改进的最大频谱配准算法，该算法利用chirp-z变换和自适应改变估计窗长的方法降低噪声对估计结果的影响，在保证估计准确度的同时控制最大频谱法的运算量，实验证明该算法比原算法的运算量更少且适用于低相干复图像配准。(3)研究了星载扫描干涉合成孔径雷达的信号特点。分析了扫描干涉合成孔径雷达信号的自相关函数特性和功率谱密度函数特性；深入研究了“方位扫描同步”现象，包括其成因、对相干系数的影响及估计方法，并结合实例进行了验证；研究了方位向配准误差对相干系数的影响。(4)分析了星载扫描干涉合成孔径雷达的系统参数。分析了影响相位误差的各种因素，详细分析了多普勒中心差异、方位向斜坡及方位扫描同步对方位向频谱偏移的影响；分析了扫描干涉合成孔径雷达系统的测高精度；研究了扫描干涉合成孔径雷达对轨道特性和方位扫描同步的要求；深入分析了S波段扫描干涉合成孔径雷达系统对偏航牵引的要求。(5)深入研究了扫描干涉合成孔径雷达数据处理方法。针对ScanSAR数据的方位向不连续性，提出了“拼接拟合-分解插值”的配准方案，实现了ScanSAR复图像的配准；针对ASAR WSS复图像中各数据线对应的“零多普勒时间”易出现不规则变化的特点，提出了“多驻留数据块联合处理与利用零多普勒时间不规则点分段处理”相结合的去除平地效应方法；提出了扫描干涉合成孔径雷达的数据处理流程。更多还原

【Abstract】 Spcace-borne Scan Interferometric Synthetic Aperture Radar (Scan-InSAR) is anew technique for wide swath elevation measurement. It is a combination of thewide swath property of ScanSAR and the elevation measurement ability ofInterferometric SAR. With the Scan-InSAR results, the elevation information of awide swath area can be obtained, which is greatly benefit to global topography; onthe other hand, monitoring the surface change of some area can be realized in shorterperiod. The Scan-InSAR system parameters and relative signal processing methodsof Scan-InSAR are studied in an all-round and systematical way in this dissertation.The main work and innovations of the dissertation are as follows:(1) Some imaging algorithms for ScanSAR mode are investigated, includingSPECAN algorithm, Full Aperture algorithm and Extended Chirp Scaling algorithm.The phase preserving properties are analyzed. Some aspects of the ECS algorithmfor ScanSAR mode are investigated deeply, such as the signal phase variation, theinfluence of range scaling function on the result and the ability of extending andshrinking image. The characteristics and applicable conditions of the threealgorithms are contrasted.(2) Interferometric SAR data processing methods are investigated. Animproved maximum spectrum peak co-registration method is proposed. The methoduse chirp-z transform and the adaptive variation of the estimation window width toreduce the computation load as well as ensure the estimation accuracy.Experimental results show that the method has lower computation load and it issuitable for low coherence data co-registration. (3) The characteristics of Scan-InSAR signal are investigated. The properties ofsignal Auto Correlation Function and Power Spectrum Density are derived in theory.The Azimuth Scan Pattern Synchronization (ASPS) is investigated deeply, includingthe origin, the influence on coherence and the estimation method, which is validatedwith real data; the influence of the azimuth miscoregistration on the coherence isderived.(4) The system parameters of Scan-InSAR are analyzed. The factors affectingphase errors are analyzed. The origins of azimuth spectrum shift in Scan-InSAR areanalyzed in detail, including Doppler Centroid difference, influence of azimuth slopeand ASPS. The elevation measurement accuracy of Scan-InSAR system is analyzed.The requirements of orbit maintenance and ASPS are brought forward. Therequirement of yaw steering for S-band ScanSAR system is analyzed in detail.(5) The Scan-InSAR data processing methods are investigated deeply. Aco-registration method called "mosaic fitting- separating interpolation" is proposedto fit for the discontinuous in azimuth direction of ScanSAR data; A flatten methodis proposed to resolve the problem of the irregular variation of the "zero Dopplertime" in the ASAR WSS data. The Scan-InSAR data processing scheme is proposed.更多还原