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Contactless deformation detection for bridge monitoring: First application of Sentinel-1 radar data in Austria
Published in Hiroshi Yokota, Dan M. Frangopol, Bridge Maintenance, Safety, Management, Life-Cycle Sustainability and Innovations, 2021
A. Vorwagner, M. Schlögl, B. Widhalm, M. Avian, D. Prammer, P. Leopold, C. Honeger
Explicit research -using the noncommercial high-resolution satellite TerraSAR-X (TSX) operated by the German Aerospace Center- tested the methods on serval structures and buildings. For example, a current project is observing hydropower dams using the highest resolution mode, the so-called Staring SpotLight with a spatial resolution of approximately 1.0 m x 0.25 m and a footprint coverage of about 5 km x 3 km. They could demonstrate that the sub-cm accuracy is possible (Lange 2019). Dam infrastructures have also been surveyed using Sentinel-1 data, delineating sub-cm/yr displacement rates (Ruiz-Armenteros et al. 2018). Applying PSI over a larger area, Sentinel-1 data has successfully been applied to detect subsidence areas in a metropolitan area (Delgado Blasco et al. 2019, Barra et al. 2016). A further example where Sentinel-1 data has been shown applicable is landslide detection, allowing to update existing maps of landslide boundaries and activity (Barra et al. 2016).
High-Resolution Radar Data Processing and Applications
Published in Yuhong He, Qihao Weng, High Spatial Resolution Remote Sensing, 2018
The Sentinel-1 mission is the European Radar Observatory for the Copernicus joint initiative of the European Commission (EC) and the European Space Agency (ESA) (ESA 2013). The two satellites of the constellation were launched April 3, 2014, and April 25, 2016. They operate in C band (5.405 GHz). The satellites share a common orbit and are spaced 180° apart. The orbital parameters of these satellites are given in Table 6.7, and descriptions of the higher resolution modes in Table 6.8. They acquire imagery in the interferometric wide (IW) mode (VV/VV + VH) over land in a fixed operational scenario, and only change to other modes under exceptional circumstances. Note that they do not support any higher resolution spotlight modes. All imagery acquired is freely available.
Overview of earth observation from satellites
Published in P. Dakin John, G. W. Brown Robert, Handbook of Optoelectronics, 2017
Greg Blackman, Jessica Rowbury
Sentinel-1A, launched in April 2014, is the first in a fleet of Sentinel satellites as part of the Copernicus programme. Sentinel-1 is a constellation of two satellites carrying radar imaging equipment. Sentinel-2 [13], launched in two parts in 2015 and 2017, carries an optical payload, imaging in the visible, near-infrared, and shortwave infrared regions in 13 spectral bands. It will have a swath width of 290 km and a revisit time of 2–3 days at mid-latitudes. Imagery from Sentinel-2 will provide similar information to the Landsat satellites and be used for areas such as land management, monitoring agriculture and forestry, and for disaster control and humanitarian relief operations.
Time-series surface water reconstruction method (TSWR) based on spatial distance relationship of multi-stage water boundaries
Published in International Journal of Digital Earth, 2022
Mingyang Li, Shanlong Lu, Cong Du, Yong Wang, Chun Fang, Xinru Li, Hailong Tang, Muhammad Hasan Ali Baig, Harrison Odion Ikhumhen
Those approaches mentioned above are frequently hampered by clouds and cloud shadows, resulting in the loss of water pixels and a high number of no-data values in final products (we refer to such images in this study as contaminated images). According to the International Satellite Cloud Climatology Project, the global average annual cloud fraction could reach 66% (Zhang et al. 2004). These cloud presence severely affects the usability of images and impedes the exploration and analysis of real change characteristics (Li et al. 2022b). The Synthetic Aperture Radar (SAR) is a very effective tool for dealing with unfavorable weather conditions because of its ability to penetrate cloud cover. Because water has very low backscatter values on SAR images, it is possible to segment the water pixels by selecting a given threshold value (Chini et al. 2017). Furthermore, the continuous archive updating of the Sentinel-1 Ground Range Detected (GRD) data on GEE enhances its ability to reduce the complexity of SAR pre-processing (DeVries et al. 2020). Sentinel-1 has the potential for dynamic monitoring, mapping of water bodies on a large scale, and the development of a variety of water data products (Li et al. 2020a; Jiang et al. 2021). The surface water dataset consisting of classified permanent water, flood water, and raw Sentinel-1 images of SEN12MS and Sen1Floods11 can be used to train and test deep learning flood algorithms (Bonafilia et al. 2020; Schmitt et al. 2019).
Paddy rice mapping in Red River Delta, Vietnam, using Sentinel 1/2 data and machine learning algorithms
Published in Journal of Spatial Science, 2023
Truong Xuan Ngo, Nam Ba Bui, Hieu Dang Trung Phan, Hoang Minh Ha, Thanh Thi Nhat Nguyen
Sentinel 1 is a satellite constellation from the European Space Agency (ESA) (Sentinel 1 2022). Sentinel 1 consists of two near polar, sun-synchronous satellites, Sentinel 1A and Sentinel 1B, carrying C-band SAR equipment with a revisit period of 6 days in Europe and 12 days in other parts of the world. The Sentinel 1 constellation provides dual-polarised Interferometric Wide (IW) swath data with Vertical Transmit – Vertical Receive (VV) and Vertical Transmit – Horizontal Receive (VH). Twelve images from the Sentinel 1 satellites were collected in 2019 from February to the end of June using Google Earth Engine (GEE) (GEE Sentinel 1 2022) with a spatial resolution of 10 × 10 m. The paper used both data channels VV and VH of Sentinel 1 images.
Investigating the seasonal dynamics of surface water over the Qinghai–Tibet Plateau using Sentinel-1 imagery and a novel gated multiscale ConvNet
Published in International Journal of Digital Earth, 2023
Sentinel-1 is a space mission funded by the European Union and carried out by the European Space Agency (ESA) within the Copernicus Programme. The Sentinel-1A and Sentinel-1B satellites were launched on 3 April 2014 and 25 April 2016, respectively. The two satellites have a repeat observation period of 12 days, so the dual-satellite constellation can provide a repeat period of 6 days. Sentinel-1 collects C-band synthetic aperture radar (central frequency of 5.404 GHz) imagery with a variety of ground resolutions depending on the acquisition mode and processing level. Sentinel-1 Ground Range Detected (GRD) scenes in interferometric wide swath (IW) acquisition mode and 10-m spatial resolution are used for our study. The Sentinel-1 C-band SAR instruments support operation in single (HH or VV) and dual polarizations (HH + HV or VV + VH). The Sentinel-1 data follow the polarization scheme; that is, HH + HV or HH polarization data are mostly used for the monitoring of polar environments and sea ice zones, while VV + VH or VV polarization data are used for other observation zones. With the accessible data archive corresponding to our study region, VV + VH images in IW mode are collected for surface water mapping in this study. In total, we acquired 2,756 dual-polarization (VV + VH) images in 2020 (Figure 2). Even though the QTP region can be fully covered by the Sentinel-1 images in each month, there are still gaps in acquiring both ascending and descending images for a specific region and month. As demonstrated in Figure 2, the accessible ascending data are richer than the descending data for the QTP region. For most of the QTP region that is covered by both Sentinel-1 ascending and descending images, simple image stacking is performed on the acquired ascending and descending images, and the stacked Sentinel-1 image is applied for monthly surface water mapping accordingly.