角反射器差分干涉方法及反距离加权最小费用流相位展开算法

合成孔径雷达差分干涉测量(Differential Interferometric Synthetic Aperture Radar,DInSAR)在低相关区由于受时间空间去相关的影响,无法得到有效应用。角反射器DInSAR方法能在长时间段内保持幅度和相位稳定性,可以最大程度地减小去相关的影响。但由于反射器在空间上一般形成不规则稀疏网络分布,在平地相位、高程相位计算及相位展开方法上都带来新的挑战。研究三角反射器的DInSAR技术,重点分析基于不规则离散点的最小费用流相位展开算法。对费用流算法权重的选择,通过分析残差的产生来源,提出以弧所穿越的边长度倒数作为弧费用的权重设置方法,解决费用流算法中具有相同费用路径的选择问题。最后将角反射器DInSAR技术应用于滑坡移动的监测,通过对140d时间段的监测,得到与实测值具有较好一致性的结果。     

三轨法DInSAR观测确定区域的垂直变形

介绍了三轨法差分合成孔径雷达干涉测量计算区域垂直地壳变形的原理和方法。采用该方法，利用我国可可西里地区的3幅ERS-2卫星SLC（Single Looking Complex）图像对该地区的垂直变形进行了计算研究。结果表明，在1998～2002年期间，研究区最大垂直变形大约为6cm。     

Integrating geotechnical and SAR data for the monitoring of underground works in the Madrid urban area: Application of the Persistent Scatterer Interferometry technique

The Differential Interferometric Synthetic Aperture Radar (DInSAR) is a powerful deformation control technique for civil engineering applications. However, the performance definition and limitations of the technique in tunneling works are far from being standardized. This work presents a thorough validation effort of the applicability of the Persistent Scatterer Interferometry (PSI) technique to the Madrid’s M-30 tunneling works. A set of 26 Envisat images, covering from August 2003 to April 2008, were processed with two PSI techniques and the results were validated with on-ground measurements from leveling benchmarks and strips. The comparison of the deformations of more than 1500 control points has led to a global deformation difference of 2.6 mm RMS and 3.5 mm RMS with a coverage of the area of interest with persistent scatterers of 65% and 34% for the two PSI algorithms used. The limitations of the PSI technique when using SAR missions with low revisit time were shown. PSI has proven the potential to complement on ground monitoring techniques in tunneling works as soon as the limitations are overcome.     

多视角InSAR数据解算2017两伊地震三维同震形变场

2017两伊地震是自1900年以来发生在扎格罗斯山脉的最大地震,为了研究此次地震引起的同震形变场,利用覆盖同一地区的3对Sentinel-1A升降轨数据分别进行两通差分DInSAR处理,得到了研究区3个视线向的地表同震形变场,通过直接解算法重建了研究区的三维同震形变场。试验表明：3种视角的升降轨视线向上升与沉降总体趋势基本一致;联合多个视角的观测结果可以实现三维形变场的重建;根据地表视线向和三维同震形变的特征以及地质构造背景推测了发震断层很有可能为扎格罗斯山前断层。     

DInSAR技术对地震同震形变场的研究

合成孔径雷达差分干涉测量（DInSAR）可用于监测厘米级或更微小的地表形变,以揭示许多物理现象,如地震形变、火山运动、大气变化、冰川漂移、地面沉降以及山体滑坡等。DInSAR作为一种新型的空间对地观测技术,具有不受时间和空间的限制、对地物具有一定的穿透性等传统测量所不可比拟的优势,已得到较为广泛的应用。简要介绍DInSAR技术的基本原理及其处理流程,以Barn地震为例提取Bam地震的同震形变场。     

使用ALOS DInSAR提取汶川地震同震地表形变场

为探测汶川Ms8.0地震引起的地表形变,用ALOS卫星PALSAR L波段SAR数据与GPS观测数据,采用两轨雷达差分干涉方法,计算出了地震影响区约83 194 km ² 范围内的同震干涉图与形变场。此外,以16个GPS点的形变数据为参考,对干涉形变的精度进行分析,结果表明：除近断层区域两类数据存在较大差异外,整体吻合程度较高。     

Inventorying slope movements in an Alpine environment using DInSAR

Differential SAR Interferometry (DInSAR) is a technique that can be used to detect and characterize slope movements. It is investigated here as a tool for establishing a detailed overview of complex slope movements at a regional scale in an Alpine context. This paper gives specific recommendations to use and to understand DInSAR signals in mountainous areas located above the tree line, excluding glaciated areas. It proposes a systematic procedure based on accurate interpretations of interferometric signals from a large DInSAR dataset to locate and estimate the displacement rate of moving zones. The methodology was successfully applied in the Western Swiss Alps, where about 1500 moving objects were detected above the tree line using a large dataset of ERS and JERS interferograms dating from the 1990s. The DInSAR‐detected movements had a displacement rate ranging from a few centimeters to several meters per year and were attributed to various types of mass wasting phenomena (rock glaciers, landslides, etc.). This kind of inventory derived from DInSAR can be used as a preliminary tool for natural hazard management and process understanding in mountain areas. As automatic data archiving and systematic acquisition of SAR data are ensured worldwide for most SAR sensors, a similar methodology can basically be applied in many other parts of the globe – also by using data from current SAR sensors – as long as a high resolution DEM is available. Copyright © 2014 John Wiley & Sons, Ltd.     

联合Envisat和ALOS卫星影像确定 L'Aquila地震震源机制

2009年4月6日意大利L'Aquila地区发生了M_w6.3级地震,该地震造成了300余人的人员死亡. 本文联合不同波长、不同入射倾角的升降轨Envisat和ALOS卫星的差分干涉数据对该地震进行震源机制解的反演研究. 研究首先对卫星雷达影像进行二通差分干涉处理,获取了覆盖L'Aquila地震震区的完整InSAR同震形变场,然后结合四叉树和均匀采样方法对原始观测数据进行降采样. 在此基础上,联合GPS形变观测数据,利用弹性半空间矩形和三角位错模型,以及断层自动剖分技术对断层面进行最优离散剖分,反演获取了发震断层的精确几何参数和最优断层滑动分布,结果显示分布式三角位错滑动模型能够很好地解释观测到的地表形变场. 反演结果表明发震断层是一个以正倾滑为主兼有少量右旋走滑的盲断层;基于观测数据最优确定的断层单元的最短边长为0.4 km,最长边长为6.3 km;此次地震的滑动分布主要发生在5～14 km深度的范围内,最大滑移量为1.07 m,释放的能量为3.43×10¹⁸ N·m(M_w6.32),与地震学的研究结果非常一致.     

基于分区解缠方式研究2010年玉树M_W6.9地震同震形变

2010年玉树MW6.9地震发生后,已有学者利用DInSAR技术得到了该次地震的同震形变场,并在此基础上反演了其震源破裂滑动分布。本文以提高玉树地震同震形变场准确度作为出发点,设计了一种新的解缠方式获取相应的同震形变场:首先沿地表同震破裂迹线将InSAR干涉图像分割成上下两部分,然后利用网络流解缠算法对其分别进行相位解缠,最后通过统计重叠部分的相位一致性信息将两部分结果进行拼接。利用震中区GPS同震位移数据对分区解缠结果进行验证。结果表明:相对于整体解缠结果,分区解缠方式得到的最大视线向沉降值由42.6cm增加到48.1cm,所得结果与GPS观测结果更加接近,采用分区解缠方式提高了断层附近形变场的准确性。