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题名	干涉SAR相关技术研究
作者	张艳洁
学位类别	工学博士
答辩日期	2004-06-01
授予单位	中国科学院研究生院
授予地点	中国科学院自动化研究所
导师	普林特 ; 胡占义
关键词	干涉图 相干性估计 小波滤波 交叉干涉测量 Interferogram Generation Coherence Estimation Wavelet Filtering Cross interferometrv
其他题名	Research On The Technique Of Interferometric SAR Processing
学位专业	模式识别与智能系统
中文摘要	合成孔径雷达(Synthetic Aperture Radar，SAR)技术始于20世纪50年代初，作 为一种主动式遥感方式，相比于光学传感器，它能够全天时、全天候获取高分辨 率遥感雷达图像。通过对同一区域不同时间获取的SAR复数图像进行干涉处理， 可以生成数字高程图和用于检测地表形变。随着遥感技术的迅速发展，SAR很 快成为微波遥感领域的重要工具，被广泛应用于地形测绘、地质研究、防灾减灾、 农林及海洋研究等国民经济的各个领域。本文针对干涉SAR处理领域中如何快 速鲁棒地生成高质量干涉图，快速无偏地进行SAR图像相干性估计，干涉图的 滤波以及ERS与Envisat图像相结合进行交叉干涉测量等问题进行了深入研究， 主要工作有： 1．实现了干涉图生成从粗配准到精配准过程的完全自动化处理。为了加快基于 相关的配准过程，本文提出了一种新的相关计算方法，该算法对复相关配准 仍然可以节约大量计算时间；在精配准过程中就如何提高精配准精度进行了 详细分析；在同名点的选取过程中，提出了一种新的基于相关系数的金字塔 坐标偏移一致性检测方法；特别地，针对于多项式插值核我们采用了Homer 多项式算法，大大节省了计算量。 2．研究了相干配准和非相干配准对SAR图像配准精度的影响，提出了利用轨道 数据计算平地条纹，然后进行基于去平SAR图像相干相关的配准方法。实验 表明这种方法可以有效地提高精配准精度，减小干涉处理导致的去相干现象。 3．研究了基于地球水平模型和椭球模型的去平地效应方法对去平结果的影响， 指出了平地相位多项式拟合方法可以大大提高计算效率；研究了基于采样相 干性幅度值的相干估计、基于去除平地相位的采样复相干性估计和基于采样 复相干平均的相干性估计对干涉SAR相干值估计结果的影响；提出了一种快 速复相干性估计算法，该算法的计算时间与估计窗尺寸几乎是无关的。 4．研究TN用小波变换进行干涉图滤波的方法。我们将在视频图像滤波处理中 获得成功应用的基于隐马尔可夫树模型(HMT)的小波滤波方法，引入到干 涉图滤波中来。鉴于基于HMT的小波滤波方法虽然有效地考虑了图像小波 变换系数的尺度间和尺度内相关性而没有充分考虑图像几何信息的约束这一 问题，我们探索了基于贝叶斯估计的小波滤波方法，尽管贝叶斯估计方法利 用了图像的几何信息约束，但是实验结果仍然不很理想。 5．对ERS和Envisat相结合进行交叉干涉测量进行了初步的理
英文摘要	As an active imaging sensor, Synthetic Aperture Radar (SAR) was born in the 1950s., Compared with optical sensor, it can acquire high resolution radar images all the day and all the time. After doing interferometric processing with the SAR SLC images of the same area acquired at different time, the results can be used to generate digital elevation model (DEM) and to detect the subtle deformation of the earth surface. Along with its advancement, SAR technology has been largely applied in many areas such as topographic mapping, hazards evaluation, geology, geodesy, land environment, atmosphere sciences and so on. This dissertation is mainly concentrated on such key issues in interferometric processing as: How to generate high quality interferograms efficiently and robustly, fast and accurate estimation of SAR images coherence, interferogram filtering, and the combination of ERS and Envisat images for cross interferometry. The main results can be summarized as follows: 1) A fully automatic interferogram gene:ration from coarse registration to fine registration is obtained. In order to calculate the correlation efficiently, a new fast correlation calculation method is proposed. It yields satisfying results even for the complex correlation calculation. Some particular efforts are dedicated to improving the registratiol: accuracy in the fine stage, Besides, a correlation ratio based pyramid method is used to select the matching points by verifying the consistency of offsets. In particular for the polynomial interpolation kernel, the Homer principle is adopted to save a large quantity of computations. 2) The accuracy of SAR images co-registration based on the coherent and non-coherent correlation is investigated. A new method is proposed to reduce the decorrelation effect where the phase of the flat earth is calculated first, then the flattend SAR complex irrtages are used for registration. The experiments validate the proposed method. 3) The flattening effects using the flat earth model and the elliptic model are compared. It is shown that the polynomial fitting of the flat earth phase can substantially improve the computational efficiency. Coherence magnitude estimate based on the sample coherence magnitude, the flattened sample complex coherence and the average of the flattened sample complex coherence are studied for their impacts on the interferometric SAR coherence estimation. A fast coherence estimation method is proposed. Its computation load is almost independent of correlation window size. 4) The problem of interferogram filtering based on Wavelet Transform is studied. The wavelet filtering method based on hidden Markov tree model (HMT), which has been successfully applied to digital image filtering, is
语种	中文
其他标识符	846
内容类型	学位论文
源URL	[http://ir.ia.ac.cn/handle/173211/5821]
专题	毕业生_博士学位论文
推荐引用方式 GB/T 7714	张艳洁. 干涉SAR相关技术研究[D]. 中国科学院自动化研究所. 中国科学院研究生院. 2004.

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