永久散射体雷达差分干涉反演矿区时序沉降场

针对永久散射体差分干涉测量(PSIn SAR)算法流程,发展了基于周期函数模型的空间维解缠方法,并将其应用于矿区时间序列地表变形反演。通过在研究区域内安装人工角反射器(CR),将CR点上计算所得的周期模型参数分量作为整个网络的约束,通过空间约束平差以实现空间维解缠。选取了河南省境内白沙水库附近的煤矿密集区为主要研究区域,采用周期函数模型对矿区线性及非线性形变分量进行模拟,反演了2007年2月—2010年2月的时间序列形变场,并采用研究区域内的水准实测数据作为外部验证数据。实验结果表明:白沙水库周围区域存在着较为明显的沉降,在煤矿分布区域内累积最大沉降量超过了10 cm。沉降区域内以线性沉降趋势为主,非线性沉降较为缓慢,仅在水库的西南方向较为明显。应用已有的水准点实测形变值对实验结果进行验证分析,结果表明该方法精度可达约±2.1 mm,证实了本文采用的方法在矿区地表时序形变反演中的可行性和可靠性,对预防过度采矿导致的矿区塌陷具重要现实意义。     

InSAR技术在沂沭断裂带地表形变监测中的应用研究

针对常规大地测量监测沂沭断裂带地表形变结果无法全面反演该区域构造应力场的局限性,尝试采用PS和SBAS两种In SAR时序分析技术对该区域地表形变进行监测。首先对SBAS-In SAR技术的原理进行详细推导和分析;在此基础上,对覆盖研究区的14景ENVISAT-ASAR数据采用PS-In SAR和SBAS-InSAR技术进行处理,分别提取了该区域地表年平均形变速率图;通过与水准监测数据的对比分析发现:InSAR时序分析方法在大范围、持续缓慢断裂带地表形变监测中能够获取与精密水准监测一致的形变趋势,且SBAS-In SAR技术在数据量较少情况下能获得更好的监测效果。这表明In SAR时序分析技术可以作为断裂带微小地表形变监测的有效手段。     

永久散射体与短基线雷达干涉测量在城市地表形变中的应用

在介绍永久散射体与短基线集雷达干涉测量方法的基础上,以辽宁省盘锦市为例,运用两种方法研究了其市区地表形变特征。对比升降轨永久散射体方法与短基线方法所得到的形变平均速率和时序分析可知,两种方法所得的研究区域的地表形变趋势较为可靠,且以垂直沉降为主,新城区是最大沉降区域,最大下沉速率达20 mm/a,其他区域较为稳定。     

时间序列InSAR监测地表形变

针对相干点目标的时间序列,提出了地表形变InSAR技术监测方法,该方法适用于小数据集分析。并采用郑州地区2007年1月到2010年4月期间的8景ALOS PALSAR数据进行验证分析。研究表明,识别的相干点目标具有大的干涉相干值和小的振幅离差,在时间序列中具有可靠的相位。从误差分析和与ENVISAT PSInSAR结果对比分析表明,该文求得的形变速率标准差在0.34mm/a和5.56mm/a之间,表明提出方法是可靠的。     

结合PS特征点的SBAS地表形变监测

针对SARscape SBAS技术存在人工选取地面控制点影响监测结果的问题,本文提出了一种结合PS特征点的SBAS地表形变监测方法。通过设置PS技术中的振幅离差指数与相干性阈值,提取PS监测结果中的特征点作为地面控制点进行轨道精炼与形变反演。以2017年3月至2018年12月覆盖南昌地区的Sentinel-1影像为数据源,进行了地表形变监测与验证。结果表明：①该方法与PS方法监测结果均显示南昌市城区在监测时段内整体呈小幅度上升趋势,年平均沉降速率相关性达到了0.959,具有高度一致性。②将该方法、PS方法、人工选取地面控制点的SBAS方法的监测结果与水准数据进行对比,该方法与水准数据的误差不超过3.5 mm,说明了该方法的有效性。     

利用时序InSAR反演常州市地表沉降速率

利用25景Envisat ASAR数据和29景高分辨率(3 m分辨率)TerraSAR-X数据,采用永久散射体干涉测量技术(PSInSAR)研究了常州市2004-2014年的地表沉降速率。结果显示,常州市的主要沉降区域发生在武进区,存在2个主要的沉降中心和1个大范围的沉降条带,2004-2010年间的地表沉降速率达到26 mm/a,2010-2014年间沉降速率变缓,最大为24 mm/a。两组数据同时段的沉降量相关性达到0.78,并利用研究区域同期水准数据检验了本文的研究结果,两者的平均速率差值均在5 mm/a以内,表明时序InSAR技术反演结果的可靠性和精度。X波段高分数据监测到C波段无法监测的高速路段存在5.3 mm/a的沉降速率,与水准结果的RMS分别为2.5、4.2 mm/a,表明TerraSAR-X比Envisat ASAR不仅具有更高密度的PS点,并且探测目标的位移具有更高的灵敏度和更高的精度。     

永久散射体雷达干涉测量技术

论述了永久散射体干涉测量(permanent scatterer interferometry, PSI)产生的背景和基本原理,并介绍了其应用实例,讨论了PSI的技术特点和今后的发展方向。     

利用RADARSAT-2雷达卫星干涉数据监测输电通道地表形变应用研究

利用2018年3月18日—2018年9月26日获取的9景5 m分辨率的RADARSAT-2数据,采用小基线集差分干涉测量技术(SBAS-InSAR)对甘肃省平凉市某输电通道进行了地表形变监测研究.结果表明,在甘肃省平凉市某输电通道发现有多处明显的地表形变现象,监测期间累积形变量最大可达7.8 cm,距离最近杆塔约430 m.现场调查与差分干涉测量结果一致,表明利用RADARSAT-2雷达卫星干涉数据监测输电通道地表形变是有效的,在广域地质灾害监测方面具有广阔的应用前景.     

基于SBAS-InSAR的长治矿区地表形变监测

小基线集InSAR(SBAS-InSAR)时序分析方法能够较好地克服InSAR时空失相干限制,抑制地形和大气影响,增加时间采样率,在监测地表形变随时间演化方面取得了较好的应用。为了有效监测山西省长治矿区地表形变,利用DInSAR方法监测开采矿区的快速大形变,得到形变区30 d的最大沉降量为11 cm;利用SBAS方法监测矿区边缘微小缓慢形变,得到2003年7月—2010年7月期间区内地面沉降的空间展布及时间序列相对形变量。对于矿区周围相干性保持较好的居民区,SBAS方法监测结果表明其整体形变表现为沉降趋势,沉降面积较大,沉降速率为5~15 mm/a,最大累计沉降为90 mm。矿区因开采时间、开采方式、采储量以及地形等因素的不同而呈现出不同的沉降结果。     

时序雷达干涉测量探测汶川地震龙门山区滑坡的时空分布特征

正Spatiotemporal pattern of wenchuan earthquake landslides in longmenshan area from time series radar interferometryCHENG HaiqinEast China Jiaotong University, Nanchang 330013, China2008年"5·12"汶川强烈地震(Ms=8.0)对龙门山区地质环境     

雷达干涉测量地表沉降和建筑物变形监测及分析

近年来,雷达干涉测量技术作为一种新兴的空间大地测量技术,凭借其非接触式、高时空分辨率等优势,克服了常规方法空间分辨率低、作业成本高等缺点,应用广泛。但其也存在一定的局限性,如星载雷达干涉测量技术受重返周期长、大气延迟等影响,难以满足高时间分辨率、高精度形变提取;地基雷达干涉测量技术虽然可有效克服星载雷达干涉测量技术的不足之处,但采用高频数据采集时,受环境变化、仪器误差等影响,雷达信号中会存在白噪声与有色噪声,影响形变信息的精确估计;雷达干涉测量技术仅可获取监测对象的几何形变信息,为更合理地评估灾害安全性还需结合监测对象形变的物理影响因子进行解释与评估。     

Investigation of the ground displacement in Saint Petersburg,Russia, using multiple-track differential synthetic aperture radar interferometry

Global sea level rise and local land subsidence might exacerbate the risk of flooding in coastal plains. Among other cities, this is also the case for the high-latitude city of St. Petersburg, which has long been threatened by flood events. To protect the urban area from storm surges, the Union of Soviet Socialist Republics (USSR) in 1978 approved the construction of the 25 km long Flood Prevention Facility Complex (FPFC), which was completed in 2011. The risk of flooding in the city area of St. Petersburg is amplified by the fact that large sections of the coastal area have been reclaimed from the sea. In this study, we investigate the temporal evolution of the ground displacement in St. Petersburg. To this end, we perform an extended analysis based on the application of a simplified version of the differential interferometric synthetic aperture radar technique, known as the minimum acceleration (MinA) approach. The MinA algorithm is a multi-satellite/multi-track interferometric combination technique that allows working with multiple sets of SAR images. The method allowed generation of time series of two-dimensional (2-D) (i.e. East-West and Up-Down) deformation of the terrain by processing two sequences of Sentinel-1A/B (S-1A/B) SAR images acquired from 2016 to 2018, along the ascending and descending flight passes. The Small BAseline Subset (SBAS) algorithm was independently applied to the two sets of SAR data to generate the relevant Line-Of-Sight (LOS)-projected ground deformation time series. Subsequently, the LOS-projected deformation products were geocoded and jointly combined. The results indicate that the deformation in the city is predominantly vertical (i.e. it is subsiding) with a maximum subsidence rate of about 20 mm/year corresponding to the newly sea-reclaimed lands. Finally, the error budget of the retrieved 2-D deformation time series has also been addressed.     

利用时序InSAR技术监测嵩明县地表形变

城市化是近代人类环境的大趋势,是每个国家现代化程度的体现,但城市发展快也会引发许多问题,其中较为严重的是地表形变,严重的地表形变容易演变成地质灾害.本文基于嵩明县现状,利用44景Sentinel-1A卫星影像通过SBAS-InSAR技术穿透云雨雾等恶劣天气对其进行地表形变监测,获得了该区域2019年1月至2020年8月...     

一种顾及永久散射体的SBAS InSAR时序地表沉降提取方法

提出了一种顾及永久散射体的SBAS InSAR时序地表形变提取方法。通过设置相干性、振幅离差指数、形变速率3阈值提取稳定的永久散射体,将其作为地面控制点引入SBAS InSAR处理流程,完成对地表形变的提取,并以郑州地区为例进行试验。获取了郑州市区2016年11月至2017年11月的地表沉降速率和时序地表沉降量,通过与PS InSAR、SBAS InSAR处理结果及水准测量进行对比,说明了该方法的可靠性。     

SBAS技术支持下的临沧市地表时序形变分析

SBAS监测技术作为微波遥感技术,通过最小二乘或奇异值分解的方法,对多个构成三角网的干涉对进行干涉处理,从而得到某个地区的时问序列形变规律.本文使用SBAS技术对覆盖临沧市2019年2月—2020年7月的30景Sentinel-1A雷达数据进行处理.通过剖面和时问序列分析方法对该区域进行分析,研究其地表沉降成因和规律,...     

Radar interferometry time series analysis of Mashhad subsidence

A large agricultural area located in 20 km north of the city of Mashhad in the north-east of Iran is subject to land subsidence. The subsidence rate was achieved in a couple of sparse points by precise leveling between 1995 and 2005, and continuous GPS measurements obtained from 2005 to 2006. In order to study the temporal behavior of the deformation in high spatial resolution, the small baseline subset (SBAS) algorithm was used to generate the interferometric SAR time series analysis. Time series analysis was performed using 19 interferograms calculated from 12 ENVISAT ASAR data spanning between 2003 and 2006. The time series results exhibited that the area is subsiding continuously without a significant seasonal effect. Mean LOS deformation velocity map obtained from time series analysis demonstrated a considerable subsidence rate up to 24 (cm/yr). In order to evaluate the time series analysis results, continuous GPS measurements as a geodetic approach were applied. The comparisons showed a great agreement between interferometry results and geodetic technique. Moreover, the information of various piezometric wells distributed in the area corresponding to 1995 to 2005 showed a significant decline in water table up to 20 meters. The correlation between the piezometric information and the surface deformation at well’s locations showed that the subsidence occurrence in Mashhad is due to the excess groundwater withdrawal.     

基于时序InSAR技术监测大桥历史形变

2019-06-14,河源市源城区东江大桥第三跨第二桥墩以及第四跨第三桥墩出现了垮塌,此次事故造成了人员伤亡和重大经济损失.为了分析此次灾害事故发生发展的成因,本研究获取了Sentinel-1A雷达卫星2018年12月至2019年6月的历史影像数据,基于时序InSAR技术手段处理得到了该监测时间段内的历史形变信息.研究...     

Advanced differential interferometry synthetic aperture radar techniques for deformation monitoring: a review on sensors and recent research development

This paper reviews the advanced differential interferometry synthetic aperture radar (A-DInSAR) techniques, with two major components in focus. First is the basic concepts, synthetic aperture radar (SAR) data sources and the different algorithms documented in the literature, primarily focusing on persistent scatterers. In the second part, the techniques are compared in order to establish more linkage in terms of the variability of their applications, strength and validation of the interpreted results. Also, current issues in sensor and algorithm development are discussed. The study identified six existing A-DInSAR algorithms used for monitoring various deformation types. Generally, reports of their performance indicate that all the techniques are capable of measuring deformation phenomena at varying spatial resolution with high level of accuracy. However, their usability in suburban and vegetated areas yields poor results, compared to urbanized areas, due to inadequate permanent features that could provide sufficient coherent point targets. Meanwhile, there is continuous development in sensors and algorithms to expand the applicability domain of the technology for a wide range of deformable surfaces and displacement patterns with higher precision. On the sensor side, most of the latest SAR sensors employ longer wavelength (X and P bands) to increase the penetrating power of the signal and two other sensors (ALOS-2 PALSA-2 and SENTINEL-1) are scheduled to be launched in 2013. Researchers are investigating the possibility of using single-pass sensors with different look angles for SAR data collection. With these, it is expected that more data will be available for various applications. Algorithms such as corner reflector interferometry SAR, along track interferometry, liqui-InSAR, and squeeSAR are emerging to increase reliable estimation of deformation from different surfaces.