Efficient Interpolation of SAR Images for Coregistration in SAR Interferometry

Phase analysis based on high-quality pixel (HQP) is crucial to ensure the measurement accuracy of ground-based SAR (GB-SAR). The amplitude dispersion (ADI) criterion has been widely applied to identify pixels with high amplitude stability, i.e., permanent scatterers (PSs), which typically are point-wise scatterers such as stones or man-made structures. However, the PS number in natural scenes is few and limits the GB-SAR applications. This paper proposes an improved method to take HQP selection applied for natural scenes in GB-SAR interferometry. In order to increase the spatial density of HQP for phase measurement, three types of HQPs including PS, quasi-permanent scatter (QPS), and distributed scatter (DS), are selected with different criteria. The ADI method is firstly utilized to take PS selection. To select those pixels with high phase stability but moderate amplitude stability, the temporal phase coherence (TPC) is defined. Those pixels with moderate ADI values and high TPC are selected as QPSs. Then the feasibility of the DS technique is explored. To validate the feasibility of the proposed method, 2370 GB-SAR images of a natural slope are processed. Experimental results prove that the HQP number could be significantly increased while slightly sacrificing phase quality.

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Monitoring Three Gorge Area Landslide currently movement by Mutilplatform SAR Interferometry

10.5194/egusphere-egu2020-5334 ◽

2020 ◽

Author(s):

Tao Li ◽

Yangmao Wen ◽

Lulu Chen ◽

Jinge Wang

Keyword(s):

High Resolution ◽

Surface Deformation ◽

Test Site ◽

Deformation Monitoring ◽

Sar Interferometry ◽

Sar Image ◽

Landslide Area ◽

Sar Images ◽

The Past ◽

Huangtupo Landslide

Three Gorge area landslide hazards developed very fast after the Dam started to impound the water since 2007. There were lots of research literatures concentrated on the Badong Huangtupo Landslide area for the whole city center had to change its position in 2009. Several literatures used Envisat SAR images time series to monitoring the surface deformation from 2008~2010. The results showed good consistent with the water level changes and precipitation. &#160;The high resolution TerraSAR Spotlight images had been used to monitoring the Shuping landslide and Fanjiaping landslide area in Zigui country from 2009~2012,the InSAR results showed good details of the landslide boundary and deformation rate with DInSAR technology.This paper studies several landslide area in the Three Gorge by InSAR technology in the past few years, such as Huangtupo, Huanglashi , Daping and &#160;Baiheping landslide area , etc. al . The high resolution SAR images covered Badong and Wushan area have been collected, including the Sentinel-1, TerraSAR, RadarSAT-2, ALOS-2 SAR images. The high resolution topography in those landslide area have been collected both by UAV lidar and high resolution topography map.The Huangtupo landslide area changed a lot in the past 3 years with the buildings ruins cleared and red soil covered by the local government. The time series results by Sentinel data in this area shows the big changes but could not derive reasonable deformation results.Three Gorges Research Center for Geo-hazards (TGRC) of China University of Geosciences(CUG) built the Badong field test site in Huangtupo landslide area. This test site is composed with a tunnel group and a series of monitoring system including the inside sensors, surface deformation monitoring sensors and so on. In this paper, we mounted several new designed dihedral corner reflectors on the Huangtupo landslide area for high precision deformation monitoring by InSAR. Both the &#160;ascending and the &#160;descending orbit data of RadarSAT-2 high resolution SAR image &#160;and TerraSAR Spotlight images have been collected in this field.The preliminary results from those new acquiring SAR data series show that the traditional landslide area such as Huanglashi , Daping, Baiheping are all moving slowly with good coherence in SAR image series. &#160;The poor vegetation coverage in those landslide area helped to get the credible &#160;InSAR results. The high resolution DEM is the critical elements for the DInSAR techniques in those landslide area. The steep&#160; topography in those landslide area distorted the SAR images correspondingly.Our results shows that it is possible to use ascending and descending high resolution SAR images to monitor the landslide area with mm level precision, while the vegetation is not so dense. High resolution SAR interferometry helped a lot for the landslide boundary detection and detailed analysis. The lower resolution SAR images such as Sentinel-1 still could provide some deformation results in landslide area, but it need more auxiliary data to interpret the results.

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Analysis of the 1993-95 Bering Glacier (Alaska) surge using differential SAR interferometry

Journal of Glaciology ◽

10.3189/s0022143000002057 ◽

1998 ◽

Vol 44 (148) ◽

pp. 532-546 ◽

Cited By ~ 8

Author(s):

Dennis R. Fatland ◽

Craig S. Lingle

Keyword(s):

Vector Fields ◽

Sar Interferometry ◽

Surface Velocity ◽

Moderate Degree ◽

Sar Images ◽

Main Trunk ◽

Bering Glacier ◽

Two Phases ◽

Differential Sar Interferometry ◽

Spaceborne Radar

AbstractDifferential spaceborne radar interferometry observations of West Bagley Icefield are used to measure surface velocity and topography. Bagley Icefield is the accumulation area fur Bering Glacier which surged in two phases from spring 1993 through summer 1905. The observations presented are based on data collected during the winter of 1992, prior to the surge, and during winter 1994 while the surge was in full progress. Both observation intervals correspond to 3 day repeat orbit phases of the ERS-I C-band SAR. This paper gives an overview of the algorithms used to derive surface-velocity vector fields and topography for valley glaciers from SAR images. The resulting high-resolution velocity data clearly show West Bagley Icefield accelerating from its quiescent pre-surge velocity by a factor of 2.7 in response to the Bering Glacier surge. Persistence of lnterfero-metric phase coherence and the relatively moderate degree of acceleration on the western arm of Bagley Icefield suggest that the velocity increase may have been caused by increased longitudinal stress gradients resulting from coupling to the surging main trunk of Bering Glacier.

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Offset tracking procedure applied to high resolution SAR data on Viedma Glacier, Patagonian Andes, Argentina

Advances in Geosciences ◽

10.5194/adgeo-35-7-2013 ◽

2013 ◽

Vol 35 ◽

pp. 7-13 ◽

Cited By ~ 18

Author(s):

N. Riveros ◽

L. Euillades ◽

P. Euillades ◽

S. Moreiras ◽

S. Balbarani

Keyword(s):

High Resolution ◽

Large Study ◽

Sar Interferometry ◽

Santa Cruz ◽

Sar Images ◽

Ice Flow ◽

Displacement Maps ◽

Patagonian Andes ◽

Offset Tracking ◽

Differential Sar Interferometry

Abstract. Main aim of this work is to explore the suitability of high resolution SAR images for measuring ice flow velocity within glaciers. Available techniques for this purpose are Differential SAR Interferometry (DInSAR) and Offset Tracking. The former, although theoretically much more precise, is frequently limited by coherence loss (or lacking of coherence) in glacier environment. The latter constitutes an alternative that works well when displacements are large. Study area is the Viedma Glacier (Santa Cruz, Argentina), one of the largest uncovered ice bodies in the South Patagonian Ice (SPI). High resolution COSMO-SkyMed (CSK) acquisitions were processed by estimating range and azimuth offset fields. Useful results, consisting in displacement maps showing areas with different fast-flowing units, were obtained by Offset Tracking processing.

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Ice-shelf dynamics near the front of the Filchner—Ronne Ice Shelf, Antarctica, revealed by SAR interferometry

Journal of Glaciology ◽

10.3189/s0022143000002732 ◽

1998 ◽

Vol 44 (147) ◽

pp. 405-418 ◽

Cited By ~ 2

Author(s):

Eric Rignot ◽

Douglas R. MacAyeal

Keyword(s):

Large Scale ◽

Sar Interferometry ◽

Velocity Shear ◽

Ocean Tide ◽

Ice Shelf ◽

Sar Images ◽

Creep Flow ◽

Iceberg Calving ◽

Shelf Dynamics ◽

Shelf Flow

AbstractFifteen synthetic aperture radar (SAR) images of the Ronne Ice Shelf (also referred to as the Filchner-Ronne Ice Shelf), Antarctica, obtained by the European remote-sensing satellites ERS-1 and -2, are used to study ice-shelf dynamics near two ends of the iceberg-calving front. Interferograms constructed from these SAR images are used to resolve the ice-shelf displacement along several directions in response to both ocean tide and long-term creep flow. Tidal motion is separated from creep flow using differential interferometry, i.e. two or more interferograms in which fringe patterns common to all are predominantly associated with creep flow. Creep-flow velocities thus determined compare well with prior ice-shelf velocity surveys. Using these data, we studied the influence of large-scale rifts, ice rises and coastal separation on the ice-shelf flow. Many of the large rifts that appear to form the boundaries where tabular icebergs may eventually detach from the ice shelf are filled with a melange of sea ice, ice-shelf debris and wind-blown snow. The interferograms show that this melange tends to deform coherently in response to the ice-shelf flow and has sufficient strength to trap large tabular ice-shelf fragments for several decades before the fragments eventually become icebergs. In many instances, the motion of the tabular fragments is a rigid-body rotation about a vertical axis that is driven by velocity shear within the melange. Tfhe mechanical role of the rift-filling melange may be to bind tabular ice-shelf fragments to the main ice shelf before they calve. This suggests two possible mechanisms by which climate could influence tabular iceberg calving. First, spatial gradients in oceanic and atmospheric temperature may determine where the melange melts and, thus, the location of the iceberg-caking margin. Second, melting or weakening of ice melange as a consequence of climate change could trigger a sudden or widespread release of tabular icebergs and lead to rapid ice-shelf disintegration.

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An Accurate Geocoding Method for GB-SAR Images Based on Solution Space Search and Its Application in Landslide Monitoring

Remote Sensing ◽

10.3390/rs13050832 ◽

2021 ◽

Vol 13 (5) ◽

pp. 832

Author(s):

Jialun Cai ◽

Hongguo Jia ◽

Guoxiang Liu ◽

Bo Zhang ◽

Qiao Liu ◽

...

Keyword(s):

Coordinate System ◽

Local Coordinate System ◽

Solution Space ◽

High Accuracy ◽

Deformation Monitoring ◽

Sar Interferometry ◽

Transformation Model ◽

Landslide Monitoring ◽

Surface Model ◽

Sar Images

Although ground-based synthetic aperture radar (GB-SAR) interferometry has a very high precision with respect to deformation monitoring, it is difficult to match the fan-shaped grid coordinates with the local topography in the geographical space because of the slant range projection imaging mode of the radar. To accurately identify the deformation target and its position, high-accuracy geocoding of the GB-SAR images must be performed to transform them from the two-dimensional plane coordinate system to the three-dimensional (3D) local coordinate system. To overcome difficulties of traditional methods with respect to the selection of control points in GB-SAR images in a complex scattering environment, a high-resolution digital surface model obtained by unmanned aerial vehicle (UAV) aerial photogrammetry was used to establish a high-accuracy GB-SAR coordinate transformation model. An accurate GB-SAR image geocoding method based on solution space search was proposed. Based on this method, three modules are used for geocoding: framework for the unification of coordinate elements, transformation model, and solution space search of the minimum Euclidean distance. By applying this method to the Laoguanjingtai landslide monitoring experiment on Hailuogou Glacier, a subpixel geocoding accuracy was realized. The effectiveness and accuracy of the proposed method were verified by contrastive analysis and error assessment. The method proposed in this study can be applied for accurate 3D interpretation and analysis of the spatiotemporal characteristic in GB-SAR deformation monitoring and should be popularized.

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Study of Spaceborne Spotlight SAR Coregistration Algorithm

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.500.368 ◽

2012 ◽

Vol 500 ◽

pp. 368-373

Author(s):

Xiao Zhen Ren ◽

Yao Qin ◽

Hong Liang Fu

Keyword(s):

Covariance Matrix ◽

Real Data ◽

Antenna Pattern ◽

Sar Interferometry ◽

Subspace Projection ◽

Sar Images ◽

Sample Number ◽

The Real ◽

Radar Satellite ◽

Azimuth Resolution

The azimuth resolution of Spotlight SAR is analyzed from the azimuth antenna pattern weighting, and the effect of the azimuth-varying Doppler on Spotlight SAR interferometry is studied. A coregistration algorithm based on adaptive subspace projection is proposed for Spotlight SAR interferometry. In this method, an adaptive factor is introduced to select the sample number of joint covariance matrix based on the coherence value. Moreover, the Doppler centroid drift in the azimuth direction is also considered in spotlight SAR images coregistration. The method is validated with the real data from the GERMAN radar satellite TerraSAR-X.

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Application of Differential SAR Interferometry in Mining Subsidence Monitoring

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.2735 ◽

2013 ◽

Vol 864-867 ◽

pp. 2735-2738

Author(s):

Wen Hai Xia ◽

Yuan Yuan Li

Keyword(s):

High Spatial Resolution ◽

Mining Subsidence ◽

Sar Interferometry ◽

Sar Images ◽

Synthetic Aperture Radar Interferometry ◽

Persistent Scatterer ◽

Technical Issues ◽

Subsidence Monitoring ◽

Differential Sar Interferometry ◽

Selection Of

Differential synthetic aperture radar Interferometry has been widely applied to monitor mining subsidence for its high spatial resolution, competent accuracy and wide coverage. In this paper, we introduce the principles of InSAR, discuss several key technical issues in mining subsidence monitoring, including selection of SAR images, advanced algorithms for phase unwrapping and Persistent Scatterer InSAR technique.

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Demonstration of Time-Series InSAR Processing in Beijing Using a Small Stack of Gaofen-3 Differential Interferograms

Journal of Sensors ◽

10.1155/2019/4204580 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13 ◽

Cited By ~ 7

Author(s):

Jili Wang ◽

Weidong Yu ◽

Yunkai Deng ◽

Robert Wang ◽

Yingjie Wang ◽

...

Keyword(s):

Time Series ◽

Land Subsidence ◽

Deformation Rate ◽

Sar Interferometry ◽

Persistent Scatterer Interferometry ◽

Sar Images ◽

Sensing Applications ◽

Persistent Scatterer ◽

Value Decomposition ◽

Orbit Errors

More and more synthetic aperture radar (SAR) satellites in orbit provide abundant data for remote sensing applications. In August 2016, China launched a new Earth observation SAR satellite, Gaofen-3 (GF-3). In this paper, we utilize a small stack of GF-3 differential interferograms to map land subsidence in Beijing (China) using the time-series SAR interferometry (InSAR) technique. The small stack of differential interferograms is generated with 5 GF-3 SAR images from March 2017 to January 2018. Orbit errors are carefully addressed and removed during differential InSAR (DInSAR) processing. Truncated singular-value decomposition (TSVD) is applied to strengthen the robustness of deformation rate estimation. To validate the results of GF-3 data, an additional deformation measurement using 26 Sentinel-1B images from March 2017 to February 2018 is carried out using the persistent scatterer interferometry (PSI) technique. By implementing a cross-comparison, we find that the retrieved results from GF-3 images and Sentinel-1 images are spatially consistent. The standard deviation of vertical deformation rate differences between two data stacks is 11.24 mm/y in the study area. The results shown in this paper demonstrate the reasonable potential of GF-3 SAR images to monitor land subsidence.

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Ice-shelf dynamics near the front of the Filchner—Ronne Ice Shelf, Antarctica, revealed by SAR interferometry

Journal of Glaciology ◽

10.1017/s0022143000002732 ◽

1998 ◽

Vol 44 (147) ◽

pp. 405-418 ◽

Cited By ~ 57

Author(s):

Eric Rignot ◽

Douglas R. MacAyeal

Keyword(s):

Large Scale ◽

Sar Interferometry ◽

Velocity Shear ◽

Ocean Tide ◽

Ice Shelf ◽

Sar Images ◽

Creep Flow ◽

Iceberg Calving ◽

Shelf Dynamics ◽

Shelf Flow

AbstractFifteen synthetic aperture radar (SAR) images of the Ronne Ice Shelf (also referred to as the Filchner-Ronne Ice Shelf), Antarctica, obtained by the European remote-sensing satellites ERS-1 and -2, are used to study ice-shelf dynamics near two ends of the iceberg-calving front. Interferograms constructed from these SAR images are used to resolve the ice-shelf displacement along several directions in response to both ocean tide and long-term creep flow. Tidal motion is separated from creep flow using differential interferometry, i.e. two or more interferograms in which fringe patterns common to all are predominantly associated with creep flow. Creep-flow velocities thus determined compare well with prior ice-shelf velocity surveys. Using these data, we studied the influence of large-scale rifts, ice rises and coastal separation on the ice-shelf flow. Many of the large rifts that appear to form the boundaries where tabular icebergs may eventually detach from the ice shelf are filled with a melange of sea ice, ice-shelf debris and wind-blown snow. The interferograms show that this melange tends to deform coherently in response to the ice-shelf flow and has sufficient strength to trap large tabular ice-shelf fragments for several decades before the fragments eventually become icebergs. In many instances, the motion of the tabular fragments is a rigid-body rotation about a vertical axis that is driven by velocity shear within the melange. Tfhe mechanical role of the rift-filling melange may be to bind tabular ice-shelf fragments to the main ice shelf before they calve. This suggests two possible mechanisms by which climate could influence tabular iceberg calving. First, spatial gradients in oceanic and atmospheric temperature may determine where the melange melts and, thus, the location of the iceberg-caking margin. Second, melting or weakening of ice melange as a consequence of climate change could trigger a sudden or widespread release of tabular icebergs and lead to rapid ice-shelf disintegration.

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