High Precision DEM Generation Algorithm Based on InSAR Multi-Look Iteration
Interferometric Synthetic Aperture Radar (InSAR) is one of the most sufficient technologies to provide global digital elevation modeling (DEM). It unwraps the interferometric phase to provide observations for phase-to-height conversion. However, the phase gradient has great influence on the phase un...
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| Format: | Article |
| Language: | English |
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MDPI AG
2017-07-01
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| Series: | Remote Sensing |
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| Online Access: | https://www.mdpi.com/2072-4292/9/7/741 |
| _version_ | 1818941613821394944 |
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| author | Xiaoming Gao Yaolin Liu Tao Li Danqin Wu |
| author_facet | Xiaoming Gao Yaolin Liu Tao Li Danqin Wu |
| author_sort | Xiaoming Gao |
| collection | DOAJ |
| description | Interferometric Synthetic Aperture Radar (InSAR) is one of the most sufficient technologies to provide global digital elevation modeling (DEM). It unwraps the interferometric phase to provide observations for phase-to-height conversion. However, the phase gradient has great influence on the phase unwrapping quality, thereby affecting the topographic mapping accuracy. Multi-look processing can improve the reliability of phase unwrapping by reducing the noise phase gradient. Nevertheless, it reduces the spatial resolution while increasing the height phase gradient, thus lowering the reliability of height values. In this paper, we propose a multi-look iteration algorithm to suppress the noise and maintain the reliability of height values. First, we use a large number of looks (NL) to suppress the noise phase gradient and obtain a coarse DEM. Then taking this coarse DEM as a reference, we remove the topographic phase from the interferogram with a small NL, which will reduce height phase gradient and ensure the accuracy of phase unwrapping. Finally, we obtain DEM products with high precision and fine resolution. We validate the proposed algorithm using both simulated and real data, and obtain DEM products in a greatly undulated region using TanDEM-X data. Results show that the proposed method is capable of providing DEM with resolution of 4 m and accuracy of 1.73 m. |
| first_indexed | 2024-12-20T06:58:20Z |
| format | Article |
| id | doaj.art-79b4dc5a8fd849409853acd7608113c7 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-12-20T06:58:20Z |
| publishDate | 2017-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-79b4dc5a8fd849409853acd7608113c72022-12-21T19:49:16ZengMDPI AGRemote Sensing2072-42922017-07-019774110.3390/rs9070741rs9070741High Precision DEM Generation Algorithm Based on InSAR Multi-Look IterationXiaoming Gao0Yaolin Liu1Tao Li2Danqin Wu3Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210046, ChinaSchool of Resource and Environmental Sciences, Wuhan University, No. 129, Luoyu Rd., Wuhan 430079, ChinaSatellite Surveying and Mapping Application Center, National Administration of Surveying, Mapping and Geo-Information, Haidian Dist., Beijing 100048, ChinaFaculty of Geosciences and Environmental Engineering, Southwest Jiaotong UniversityInterferometric Synthetic Aperture Radar (InSAR) is one of the most sufficient technologies to provide global digital elevation modeling (DEM). It unwraps the interferometric phase to provide observations for phase-to-height conversion. However, the phase gradient has great influence on the phase unwrapping quality, thereby affecting the topographic mapping accuracy. Multi-look processing can improve the reliability of phase unwrapping by reducing the noise phase gradient. Nevertheless, it reduces the spatial resolution while increasing the height phase gradient, thus lowering the reliability of height values. In this paper, we propose a multi-look iteration algorithm to suppress the noise and maintain the reliability of height values. First, we use a large number of looks (NL) to suppress the noise phase gradient and obtain a coarse DEM. Then taking this coarse DEM as a reference, we remove the topographic phase from the interferogram with a small NL, which will reduce height phase gradient and ensure the accuracy of phase unwrapping. Finally, we obtain DEM products with high precision and fine resolution. We validate the proposed algorithm using both simulated and real data, and obtain DEM products in a greatly undulated region using TanDEM-X data. Results show that the proposed method is capable of providing DEM with resolution of 4 m and accuracy of 1.73 m.https://www.mdpi.com/2072-4292/9/7/741InSARmulti-look iterationDEMTanDEM-X |
| spellingShingle | Xiaoming Gao Yaolin Liu Tao Li Danqin Wu High Precision DEM Generation Algorithm Based on InSAR Multi-Look Iteration Remote Sensing InSAR multi-look iteration DEM TanDEM-X |
| title | High Precision DEM Generation Algorithm Based on InSAR Multi-Look Iteration |
| title_full | High Precision DEM Generation Algorithm Based on InSAR Multi-Look Iteration |
| title_fullStr | High Precision DEM Generation Algorithm Based on InSAR Multi-Look Iteration |
| title_full_unstemmed | High Precision DEM Generation Algorithm Based on InSAR Multi-Look Iteration |
| title_short | High Precision DEM Generation Algorithm Based on InSAR Multi-Look Iteration |
| title_sort | high precision dem generation algorithm based on insar multi look iteration |
| topic | InSAR multi-look iteration DEM TanDEM-X |
| url | https://www.mdpi.com/2072-4292/9/7/741 |
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