An Improved Method of Noise Subtraction for the CFOSAT Scatterometer
The microwave scatterometer onboard the China-France Oceanography Satellite (CFOSAT Scatterometer, CSCAT) is the first rotating fan-beam scatterometer (RFSCAT) in operation. It is used to obtain the ocean surface wind field by measuring the backscattering coefficient over a large observation swath....
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| Format: | Article |
| Language: | English |
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IEEE
2021-01-01
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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/9468962/ |
| _version_ | 1818356766550786048 |
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| author | Kuo Zhang Xiaolong Dong Di Zhu Risheng Yun Binghua Wang Miaomiao Yu |
| author_facet | Kuo Zhang Xiaolong Dong Di Zhu Risheng Yun Binghua Wang Miaomiao Yu |
| author_sort | Kuo Zhang |
| collection | DOAJ |
| description | The microwave scatterometer onboard the China-France Oceanography Satellite (CFOSAT Scatterometer, CSCAT) is the first rotating fan-beam scatterometer (RFSCAT) in operation. It is used to obtain the ocean surface wind field by measuring the backscattering coefficient over a large observation swath. To estimate the backscattering coefficient, the scatterometer needs to measure the scattered signal accurately. The process of removing noise from the echo signal (scattered signal plus noise) is called noise subtraction. Noise subtraction has a great influence on the measurement of the backscattering coefficient and subsequent wind field retrieval. Therefore, accurate noise subtraction is necessary and important. In this article, an improved noise subtraction method for CSCAT is proposed. According to the distribution characteristics of backscattering coefficients, noise correction factors are introduced to improve the noise subtraction of CSCAT. The ocean surface wind fields are obtained using the improved backscattering coefficient data, and the deviation of wind speed and direction are calculated by comparison with the European Centre for Medium Range Weather Forecasts wind fields. The results show that the improved noise subtraction method can lead to improvement of the quality of wind field effectively. In addition, based on the improved method of noise subtraction, a method of estimating the noise correction factor is proposed at a large incidence angle, furtherly improving the noise subtraction method. The results show that the proposed method is effective. |
| first_indexed | 2024-12-13T20:02:26Z |
| format | Article |
| id | doaj.art-b9524d4340ac441c92d945008efbefdd |
| institution | Directory Open Access Journal |
| issn | 2151-1535 |
| language | English |
| last_indexed | 2024-12-13T20:02:26Z |
| publishDate | 2021-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing |
| spelling | doaj.art-b9524d4340ac441c92d945008efbefdd2022-12-21T23:33:08ZengIEEEIEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing2151-15352021-01-01147506751510.1109/JSTARS.2021.30935599468962An Improved Method of Noise Subtraction for the CFOSAT ScatterometerKuo Zhang0https://orcid.org/0000-0001-7571-9093Xiaolong Dong1https://orcid.org/0000-0001-9515-9281Di Zhu2Risheng Yun3Binghua Wang4Miaomiao Yu5Key Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing, ChinaKey Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing, ChinaKey Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing, ChinaKey Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing, ChinaKey Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing, ChinaKey Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing, ChinaThe microwave scatterometer onboard the China-France Oceanography Satellite (CFOSAT Scatterometer, CSCAT) is the first rotating fan-beam scatterometer (RFSCAT) in operation. It is used to obtain the ocean surface wind field by measuring the backscattering coefficient over a large observation swath. To estimate the backscattering coefficient, the scatterometer needs to measure the scattered signal accurately. The process of removing noise from the echo signal (scattered signal plus noise) is called noise subtraction. Noise subtraction has a great influence on the measurement of the backscattering coefficient and subsequent wind field retrieval. Therefore, accurate noise subtraction is necessary and important. In this article, an improved noise subtraction method for CSCAT is proposed. According to the distribution characteristics of backscattering coefficients, noise correction factors are introduced to improve the noise subtraction of CSCAT. The ocean surface wind fields are obtained using the improved backscattering coefficient data, and the deviation of wind speed and direction are calculated by comparison with the European Centre for Medium Range Weather Forecasts wind fields. The results show that the improved noise subtraction method can lead to improvement of the quality of wind field effectively. In addition, based on the improved method of noise subtraction, a method of estimating the noise correction factor is proposed at a large incidence angle, furtherly improving the noise subtraction method. The results show that the proposed method is effective.https://ieeexplore.ieee.org/document/9468962/Backscattering coefficientsnoise correction factorsnoise subtraction methodscatterometer |
| spellingShingle | Kuo Zhang Xiaolong Dong Di Zhu Risheng Yun Binghua Wang Miaomiao Yu An Improved Method of Noise Subtraction for the CFOSAT Scatterometer IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Backscattering coefficients noise correction factors noise subtraction method scatterometer |
| title | An Improved Method of Noise Subtraction for the CFOSAT Scatterometer |
| title_full | An Improved Method of Noise Subtraction for the CFOSAT Scatterometer |
| title_fullStr | An Improved Method of Noise Subtraction for the CFOSAT Scatterometer |
| title_full_unstemmed | An Improved Method of Noise Subtraction for the CFOSAT Scatterometer |
| title_short | An Improved Method of Noise Subtraction for the CFOSAT Scatterometer |
| title_sort | improved method of noise subtraction for the cfosat scatterometer |
| topic | Backscattering coefficients noise correction factors noise subtraction method scatterometer |
| url | https://ieeexplore.ieee.org/document/9468962/ |
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