基于D-InSAR技术的公路采空区变形监测

利用某高速采空区的ALOS卫星6景PALSAR数据,采用二轨差分干涉处理的数学模型,在完成图像的配准、重采样、去除地形相位、滤波和相位解缠之后,获取了高速公路采空区D-InSAR条带变形时间序列,并与实测数据进行了比较,将InSAR数据进行改正,结果显示D-InSAR用于公路采空区变形监测是可行的,具有广泛的应用前景。     

天地一体化地物变化监测与风险评估

外力破坏和地质灾害是威胁油气管道安全的两大隐患,传统的人工巡检和地基传感器监测方式存在一定的局限性。本文基于高分辨率卫星光学影像,通过利用多学科交叉、多领域前沿科技融合技术,深入分析和研究高分辨率遥感影像特点,研究多种优化的变化检测算法,构建了集多种算法于一体的自动变化检测软件,解决了管道沿线施工变化情况和工程车辆的自动检测,另外,该技术还可用于对高后果区内建筑物的变化进行定期统计更新。同时,本文基于星载合成孔径雷达(SAR)影像,采用InSAR方法分析了管道沿线的地质形变,并辅以卫星光学影像、气象、地基传感器、水文、地质等多源数据,建立基于卫星遥感的空天地一体化地质灾害监测体系和技术识别方法,实现地质灾害的天地一体化综合识别与预警。     

机载毫米波InSAR技术测制3D产品精度分析

文中介绍了机载毫米波InSAR地形测绘的原理与方法,并通过试验研究,分析了机载毫米波InSAR技术测制的3D(DEM、DOM、DLG)成果的平面精度和高程精度。讨论了影响DEM高程精度和DLG平面精度的因素。试验表明采用我国自主研发的机载毫米波InSAR系统测制的3D成果,满足1∶5000国家规范的精度要求。     

永久散射体识别方法研究

在永久散射体雷达差分干涉测量（PSInSAR）算法流程中,PS点的探测与识别是重要环节。本文在分析几种较常用PS点目标提取方法的基础上,设计了一套将相干系数阈值法,振幅离差指数阈值法与强度阈值法串行的PS点目标识别方法,并将这一三重阈值串行的探测方法应用在河南地区的14景SAR影像中探测PS点目标,通过实验分别比对了研究区域内各种方法在不同阈值组合情况下提取出来的PS点效果,通过对实验结果分析可知,三重指数串行法获取的PS候选点分布情况更合理,更适用于该研究区域应用PSInSAR进行形变监测。     

The Al Hoceima (Morocco) earthquake of 24 February 2004, analysis and interpretation of data from ENVISAT ASAR and SPOT5 validated by ground-based observations

The magnitude M_w = 6.3 earthquake in Al Hoceima, Morocco of 24 February, 2004 occurred in the active plate boundary accommodating the oblique convergence between Africa and Eurasia. Three different sets of estimates of its source parameters have already been published. We try to resolve the discrepancies between them by using additional data including two remote sensing satellite systems (ENVISAT and SPOT5). Using a model with a dislocation in an elastic half-space, we constrain the source parameters. The hypothesis of two subevents on distinct faults as inferred from seismological inversions is confirmed here by adopting a cross-fault mechanism. The rupture began on a left-lateral strike-slip fault striking at N10° azimuth with 90 cm of horizontal slip and then transferred to a right-lateral strike-slip fault striking at N312° azimuth with 85 cm of horizontal slip. The first fault is at 500 m depth from the free surface and the second fault is at 3 km depth. This model is consistent with ground-based observations, including GPS, seismology, and mapped surface fissures. The pair of faults activated in 2004 appears to constitute part of a complex seismogenic structure striking NNE-SSW that separates the Rif tectonic blocks.     

InSAR相位解缠算法的分析与评价研究

相位解缠是合成孔径雷达干涉测量中的一个关键步骤,也是主要的误差源之一,同时也是研究InSAR的一个重点和难点。相位解缠算法的选取对InSAR最终的成果(DEM或者形变量)有很大的影响。文中选取常用的Goldstein枝切算法、预解共轭梯度法(PCG)以及最为流行的统计费用网络流算法(Snaphu)对西安地区的实例数据进行了解缠运算,采用不同的评价标准对解缠结果的质量进行了评价比较,并分析给出了各自解缠算法的特点和适用情况,最后对相位解缠算法的未来发展方向进行了展望。     

利用物探遥感技术探查城市道路塌陷隐患

城市道路塌陷隐患排查对城市公共安全具有重要意义.本文利用物探和InSAR遥感技术,以南京市鼓楼区域为实验区,对道路塌陷隐患进行了探查和研究.利用InSAR技术获取2019年～2020年南京市鼓楼区主要道路的形变梯度信息;结合软土层厚度、管道渗漏点和轨道交通分布等信息,利用层次分析法建立道路塌陷评估模型,对实验区道路塌陷...     

Effect of digital elevation models on monitoring slope displacements in open-pit mine by differential interferometry synthetic aperture radar

Displacement monitoring in open-pit mines is one of the important tasks for safe management of mining processes. Differential interferometric synthetic aperture radar (DInSAR), mounted on an artificial satellite, has the potential to be a cost-effective method for monitoring surface displacements over extensive areas, such as open-pit mines. DInSAR requires the ground surface elevation data in the process of its analysis as a digital elevation model (DEM). However, since the topography of the ground surface in open-pit mines changes largely due to excavations, measurement errors can occur due to insufficient information on the elevation of mining areas. In this paper, effect of different elevation models on the accuracy of the displacement monitoring results by DInSAR is investigated at a limestone quarry. In addition, validity of the DInSAR results using an appropriate DEM is examined by comparing them with the results obtained by global positioning system (GPS) monitoring conducted for three years at the same limestone quarry. It is found that the uncertainty of DEMs induces large errors in the displacement monitoring results if the baseline length of the satellites between the master and the slave data is longer than a few hundred meters. Comparing the monitoring results of DInSAR and GPS, the root mean square error (RMSE) of the discrepancy between the two sets of results is less than 10 mm if an appropriate DEM, considering the excavation processes, is used. It is proven that DInSAR can be applied for monitoring the displacements of mine slopes with centimeter-level accuracy.     

基于联合像素模型和WAVES的频InSAR相位融合

提出了一种基于联合像素模型和信号子空间加权平均方法(weighted average of signal subspaces,WAVES)的多频带InSAR自适应相位融合方法.首先,采用联合像素模型对各频带InSAR信号建模,然后,借鉴WAVES的思想对多频带信号子空间进行聚焦和加权,获得通用协方差矩阵,最后,利用窄带估计方法估计出绝对干涉相位.该方法可以在图像配准精度很差(可以允许达到一个分辨单元)的条件下获得稳健的干涉相位估计性能,仿真数据和SIR-C实际雷达数据验证了此方法的有效性.     

小波变换和加权圆周期中值算法的InSAR干涉纹图除噪

针对InSAR中干涉相位条纹图的除噪滤波,提出了一种基于小波变换和加权圆周期中值算法的干涉纹图除噪方法,阐述了该方法的设计思想和具体算法实现步骤。实验结果证明该方法不仅有效地抑制了干涉纹图中的噪声,并且较好的保持了干涉纹图的相位信息。