Characterization of the Amazon Rainforest Backscatter at X-Band Using TanDEM-X Data
The radiometric calibration of spaceborne SAR products plays a key role for ensuring a good performance of the whole end-to-end system and requires a precise knowledge of both the radar system and the illuminated target on ground. The shape of the antenna pattern in elevation can be directly estimat...
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| Format: | Article |
| Language: | English |
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IEEE
2024-01-01
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| Series: | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/10339797/ |
| _version_ | 1797374411524800512 |
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| author | Luca Dell'Amore Jose-Luis Bueso-Bello Patrick Klenk Jens Reimann Paola Rizzoli |
| author_facet | Luca Dell'Amore Jose-Luis Bueso-Bello Patrick Klenk Jens Reimann Paola Rizzoli |
| author_sort | Luca Dell'Amore |
| collection | DOAJ |
| description | The radiometric calibration of spaceborne SAR products plays a key role for ensuring a good performance of the whole end-to-end system and requires a precise knowledge of both the radar system and the illuminated target on ground. The shape of the antenna pattern in elevation can be directly estimated by analyzing SAR detected images in presence of a homogeneous and flat backscatter profile in the slant range dimension. To this aim, tropical rainforests have been established by the SAR community as well-known calibration sites for performing such an activity. Here, according to the hypothesis of isotropic scattering, the backscattering coefficient in terms of unit area perpendicular to the antenna, called gamma nought, is assumed to remain constant with respect to the incidence angle. Nevertheless, several studies using X- and C-band sensors have shown a slight dependency of the backscatter on the incidence angle, as well as on ground target properties and meteorological conditions. In this work, we present a detailed statistical characterization of radar backscatter at X-band over the Amazon rainforest using TanDEM-X data and we provide insights on how to best utilize radar backscatter data in this region for SAR calibration and modeling purposes. In particular, we concentrate on the dependency of the Amazon rainforest backscatter on the day-time of acquisition, which is directly related to the orbit direction of TanDEM-X. Furthermore, we analyze the seasonal variation of the radar backscatter, as well as possible radiation variations over different locations in the Amazon, characterized by different climate conditions and biomes. Finally, we provide a series of backscatter models for different scenarios, which can be used, e.g., for X-band spaceborne SAR system design and theoretical modeling. |
| first_indexed | 2024-03-08T19:05:27Z |
| format | Article |
| id | doaj.art-1aa3c14bfd144ff2a3056e9c12ca6ec2 |
| institution | Directory Open Access Journal |
| issn | 2151-1535 |
| language | English |
| last_indexed | 2024-03-08T19:05:27Z |
| publishDate | 2024-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing |
| spelling | doaj.art-1aa3c14bfd144ff2a3056e9c12ca6ec22023-12-28T00:02:13ZengIEEEIEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing2151-15352024-01-01171673169010.1109/JSTARS.2023.333898210339797Characterization of the Amazon Rainforest Backscatter at X-Band Using TanDEM-X DataLuca Dell'Amore0https://orcid.org/0000-0002-6731-1300Jose-Luis Bueso-Bello1https://orcid.org/0000-0003-3464-2186Patrick Klenk2https://orcid.org/0000-0002-8284-2265Jens Reimann3https://orcid.org/0000-0002-0650-9073Paola Rizzoli4https://orcid.org/0000-0001-9118-2732Microwaves and Radar Institute, German Aerospace Center, Wessling, GermanyMicrowaves and Radar Institute, German Aerospace Center, Wessling, GermanyMicrowaves and Radar Institute, German Aerospace Center, Wessling, GermanyMicrowaves and Radar Institute, German Aerospace Center, Wessling, GermanyMicrowaves and Radar Institute, German Aerospace Center, Wessling, GermanyThe radiometric calibration of spaceborne SAR products plays a key role for ensuring a good performance of the whole end-to-end system and requires a precise knowledge of both the radar system and the illuminated target on ground. The shape of the antenna pattern in elevation can be directly estimated by analyzing SAR detected images in presence of a homogeneous and flat backscatter profile in the slant range dimension. To this aim, tropical rainforests have been established by the SAR community as well-known calibration sites for performing such an activity. Here, according to the hypothesis of isotropic scattering, the backscattering coefficient in terms of unit area perpendicular to the antenna, called gamma nought, is assumed to remain constant with respect to the incidence angle. Nevertheless, several studies using X- and C-band sensors have shown a slight dependency of the backscatter on the incidence angle, as well as on ground target properties and meteorological conditions. In this work, we present a detailed statistical characterization of radar backscatter at X-band over the Amazon rainforest using TanDEM-X data and we provide insights on how to best utilize radar backscatter data in this region for SAR calibration and modeling purposes. In particular, we concentrate on the dependency of the Amazon rainforest backscatter on the day-time of acquisition, which is directly related to the orbit direction of TanDEM-X. Furthermore, we analyze the seasonal variation of the radar backscatter, as well as possible radiation variations over different locations in the Amazon, characterized by different climate conditions and biomes. Finally, we provide a series of backscatter models for different scenarios, which can be used, e.g., for X-band spaceborne SAR system design and theoretical modeling.https://ieeexplore.ieee.org/document/10339797/Amazon rainforestSAR calibrationsynthetic aperture radar (SAR)TanDEM-X (TDX) |
| spellingShingle | Luca Dell'Amore Jose-Luis Bueso-Bello Patrick Klenk Jens Reimann Paola Rizzoli Characterization of the Amazon Rainforest Backscatter at X-Band Using TanDEM-X Data IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Amazon rainforest SAR calibration synthetic aperture radar (SAR) TanDEM-X (TDX) |
| title | Characterization of the Amazon Rainforest Backscatter at X-Band Using TanDEM-X Data |
| title_full | Characterization of the Amazon Rainforest Backscatter at X-Band Using TanDEM-X Data |
| title_fullStr | Characterization of the Amazon Rainforest Backscatter at X-Band Using TanDEM-X Data |
| title_full_unstemmed | Characterization of the Amazon Rainforest Backscatter at X-Band Using TanDEM-X Data |
| title_short | Characterization of the Amazon Rainforest Backscatter at X-Band Using TanDEM-X Data |
| title_sort | characterization of the amazon rainforest backscatter at x band using tandem x data |
| topic | Amazon rainforest SAR calibration synthetic aperture radar (SAR) TanDEM-X (TDX) |
| url | https://ieeexplore.ieee.org/document/10339797/ |
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