• Title/Summary/Keyword: SqueeSAR

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Deformation monitoring of Daejeon City using ALOS-1 PALSAR - Comparing the results by PSInSAR and SqueeSAR - (ALOS-1 PALSAR 영상을 이용한 대전지역 변위 관측 - PSInSAR와 SqueeSAR 분석 결과 비교 -)

  • Kim, Sang-Wan
    • Korean Journal of Remote Sensing
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    • v.32 no.6
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    • pp.567-577
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    • 2016
  • SqueeSAR is a new technique to combine Persistent Scatterer (PS) and Distributed Scatterer (DS) for deformation monitoring. Although many PSs are available in urban areas, SqueeSAR analysis can be beneficial to increase the PS density in not only natural targets but also smooth surfaces in urban environment. The height of each targets is generally required to remove topographic phase in interferometric SAR processing. The result of PSInSAR analysis to use PS only is not affected by DEM resolution because the height error of initial input DEM at each PSs is precisely compensated in PS processing chain. On the contrary, SqueeSAR can be affected by DEM resolution and precision since it includes spatial average filtering for DS targets to increase a signal-to-noise ratio (SNR). In this study we observe the effect of DEM resolution on deformation measurement by PSInSAR and SqueeSAR. With ALOS-1 PALSAR L-band data, acquired over Daejeon city, Korea, two different DEM data are used in InSAR processing for comparison: 1 m LIDAR DEM and SRTM 1-arc (~30 m) DEM. As expected the results of PSInSAR analysis show almost same results independently of the kind of DEM, while the results of SqueeSAR analysis show the improvement in quality of the time-series in case of 1-m LIDAR DSM. The density of InSAR measurement points was also improved about five times more than the PSInSAR analysis.

Comparison of SqueeSAR Analysis Method And Level Surveying for Subsidence Monitoring at Landfill Site (매립지 지반침하 모니터링을 위한 SqueeSAR 해석법과 수준측량의 비교)

  • Kim, Dal-Joo;Lee, Yong-Chang
    • Journal of Cadastre & Land InformatiX
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    • v.48 no.2
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    • pp.137-151
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    • 2018
  • Recently, National interest has been rising due to earthquakes in Gyeongju and Pohang, disasters caused by landslides, landslides, and sinkholes around construction sites, and damage caused by disasters. SAR is able to detect ground displacement in mm for wide area, collect data through satellite, predict timeliness of crustal change by time series analysis, and reduce disaster and disaster damage. The purpose of this study is to investigate the latest SAR interference analysis technique (SqueeSAR analysis technique) of Sentinel-1A satellite (SAR sensor) of European ESA for about 3 years by selecting the 1st landfill site in the metropolitan area in Incheon, The settlement amount was calculated in a time series. Especially, in order to examine the accuracy of the subsidence and subsidence tendency by the SqueeSAR analysis method, the ground level survey was compared and analyzed for the first time in Korea. Also, the tendency of the subsidence trend was predicted by analyzing the time series and correlation trend of the subsidence for three years. Through this study, it is expected that disaster prevention and disaster prevention such as sinkhole and landslide can be utilized from time series monitoring of crustal variation of the land.