SodSAR: A Tower-Based 1–10 GHz SAR System for Snow, Soil and Vegetation Studies
We introduce SodSAR, a fully polarimetric tower-based wide frequency (1–10 GHz) range Synthetic Aperture Radar (SAR) aimed at snow, soil and vegetation studies. The instrument is located in the Arctic Space Centre of the Finnish Meteorological Institute in Sodankylä, Finland. The system is based on...
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| Language: | English |
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MDPI AG
2020-11-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/20/22/6702 |
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| author | Jorge Jorge Ruiz Risto Vehmas Juha Lemmetyinen Josu Uusitalo Janne Lahtinen Kari Lehtinen Anna Kontu Kimmo Rautiainen Riku Tarvainen Jouni Pulliainen Jaan Praks |
| author_facet | Jorge Jorge Ruiz Risto Vehmas Juha Lemmetyinen Josu Uusitalo Janne Lahtinen Kari Lehtinen Anna Kontu Kimmo Rautiainen Riku Tarvainen Jouni Pulliainen Jaan Praks |
| author_sort | Jorge Jorge Ruiz |
| collection | DOAJ |
| description | We introduce SodSAR, a fully polarimetric tower-based wide frequency (1–10 GHz) range Synthetic Aperture Radar (SAR) aimed at snow, soil and vegetation studies. The instrument is located in the Arctic Space Centre of the Finnish Meteorological Institute in Sodankylä, Finland. The system is based on a Vector Network Analyzer (VNA)-operated scatterometer mounted on a rail allowing the formation of SAR images, including interferometric pairs separated by a temporal baseline. We present the description of the radar, the applied SAR focusing technique, the radar calibration and measurement stability analysis. Measured stability of the backscattering intensity over a three-month period was observed to be better than 0.5 dB, when measuring a target with a known radar cross section. Deviations of the estimated target range were in the order of a few cm over the same period, indicating also good stability of the measured phase. Interforometric SAR (InSAR) capabilities are also discussed, and as a example, the coherence of subsequent SAR acquisitions over the observed boreal forest stand are analyzed over increasing temporal baselines. The analysis shows good conservation of coherence in particular at L-band, while higher frequencies are susceptible to loss of coherence in particular for dense vegetation. The potential of the instrument for satellite calibration and validation activities is also discussed. |
| first_indexed | 2024-03-10T14:37:59Z |
| format | Article |
| id | doaj.art-7958e0d152a3411eaee7cf0f1436eb16 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-10T14:37:59Z |
| publishDate | 2020-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-7958e0d152a3411eaee7cf0f1436eb162023-11-20T22:00:04ZengMDPI AGSensors1424-82202020-11-012022670210.3390/s20226702SodSAR: A Tower-Based 1–10 GHz SAR System for Snow, Soil and Vegetation StudiesJorge Jorge Ruiz0Risto Vehmas1Juha Lemmetyinen2Josu Uusitalo3Janne Lahtinen4Kari Lehtinen5Anna Kontu6Kimmo Rautiainen7Riku Tarvainen8Jouni Pulliainen9Jaan Praks10Finnish Meteorological Institute, Erik Palménin Aukio 1, 00560 Helsinki, FinlandFraunhofer Institute for High Frequency Physics and Radar Techniques FHR, Fraunhoferstraße 20, 53343 Wachtberg, GermanyFinnish Meteorological Institute, Erik Palménin Aukio 1, 00560 Helsinki, FinlandHarp Technologies Ltd., Tekniikantie 14, 02150 Espoo, FinlandHarp Technologies Ltd., Tekniikantie 14, 02150 Espoo, FinlandHarp Technologies Ltd., Tekniikantie 14, 02150 Espoo, FinlandFinnish Meteorological Institute, Erik Palménin Aukio 1, 00560 Helsinki, FinlandFinnish Meteorological Institute, Erik Palménin Aukio 1, 00560 Helsinki, FinlandFinnish Meteorological Institute, Erik Palménin Aukio 1, 00560 Helsinki, FinlandFinnish Meteorological Institute, Erik Palménin Aukio 1, 00560 Helsinki, FinlandDepartment of Electronics and Nanoengineering, Aalto University, Maarintie 8, 02150 Espoo, FinlandWe introduce SodSAR, a fully polarimetric tower-based wide frequency (1–10 GHz) range Synthetic Aperture Radar (SAR) aimed at snow, soil and vegetation studies. The instrument is located in the Arctic Space Centre of the Finnish Meteorological Institute in Sodankylä, Finland. The system is based on a Vector Network Analyzer (VNA)-operated scatterometer mounted on a rail allowing the formation of SAR images, including interferometric pairs separated by a temporal baseline. We present the description of the radar, the applied SAR focusing technique, the radar calibration and measurement stability analysis. Measured stability of the backscattering intensity over a three-month period was observed to be better than 0.5 dB, when measuring a target with a known radar cross section. Deviations of the estimated target range were in the order of a few cm over the same period, indicating also good stability of the measured phase. Interforometric SAR (InSAR) capabilities are also discussed, and as a example, the coherence of subsequent SAR acquisitions over the observed boreal forest stand are analyzed over increasing temporal baselines. The analysis shows good conservation of coherence in particular at L-band, while higher frequencies are susceptible to loss of coherence in particular for dense vegetation. The potential of the instrument for satellite calibration and validation activities is also discussed.https://www.mdpi.com/1424-8220/20/22/6702SodSARsynthetic aperture radarInSARboreal forestvector network analyzerscatterometer |
| spellingShingle | Jorge Jorge Ruiz Risto Vehmas Juha Lemmetyinen Josu Uusitalo Janne Lahtinen Kari Lehtinen Anna Kontu Kimmo Rautiainen Riku Tarvainen Jouni Pulliainen Jaan Praks SodSAR: A Tower-Based 1–10 GHz SAR System for Snow, Soil and Vegetation Studies Sensors SodSAR synthetic aperture radar InSAR boreal forest vector network analyzer scatterometer |
| title | SodSAR: A Tower-Based 1–10 GHz SAR System for Snow, Soil and Vegetation Studies |
| title_full | SodSAR: A Tower-Based 1–10 GHz SAR System for Snow, Soil and Vegetation Studies |
| title_fullStr | SodSAR: A Tower-Based 1–10 GHz SAR System for Snow, Soil and Vegetation Studies |
| title_full_unstemmed | SodSAR: A Tower-Based 1–10 GHz SAR System for Snow, Soil and Vegetation Studies |
| title_short | SodSAR: A Tower-Based 1–10 GHz SAR System for Snow, Soil and Vegetation Studies |
| title_sort | sodsar a tower based 1 10 ghz sar system for snow soil and vegetation studies |
| topic | SodSAR synthetic aperture radar InSAR boreal forest vector network analyzer scatterometer |
| url | https://www.mdpi.com/1424-8220/20/22/6702 |
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