An Iterative Adaptive Polarization Calibration Method Independent of Corner Reflectors
Polarimetric calibration (PolCal) is essential for the quantitative processing of polarimetric synthetic aperture radar data. Traditional distributed target methods typically require at least one corner reflector (CR) to determine the copolarization (co-pol) channel imbalance. However, the deploymen...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IEEE
2025-01-01
|
| Series: | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/10854647/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849716192026034176 |
|---|---|
| author | Bowen Chi Jixian Zhang Guoman Huang Lijun Lu Shucheng Yang |
| author_facet | Bowen Chi Jixian Zhang Guoman Huang Lijun Lu Shucheng Yang |
| author_sort | Bowen Chi |
| collection | DOAJ |
| description | Polarimetric calibration (PolCal) is essential for the quantitative processing of polarimetric synthetic aperture radar data. Traditional distributed target methods typically require at least one corner reflector (CR) to determine the copolarization (co-pol) channel imbalance. However, the deployment of CRs is costly and impractical in challenging areas, and therefore, advanced PolCal methods that do not rely on CRs have been developed. One widely used method estimates crosstalk and cross-polarization channel imbalance based on volume-dominated pixels. This method estimates co-pol channel imbalance based on Bragg-like pixels, using the Gauss−Newton method according to the unitary zero helix (UZH) constraint and obtains the final co-pol channel imbalance through fitting. However, the selection of initial values and step sizes affects the convergence of the Gauss−Newton method, while the fixed threshold used in fitting impacts the accuracy of sample selection. These issues collectively influence the precision of the calibration results. Therefore, we proposed an iterative adaptive PolCal method to improve the UZH method from a computational perspective. This method first uses an iterative process to obtain a more accurate global initial value for each block's initial input. It then combined the Levenberg−Marquardt algorithm to adjust step sizes and solve for each block. In addition, the variation coefficient was introduced to achieve adaptive sample selection and enhance fitting accuracy. The effectiveness of our proposed method was validated using GF3 02 satellite two-scene calibration field images. The experiments demonstrated that the proposed method not only ensured convergence but also improved the accuracy and stability of PolCal methods without CRs. |
| format | Article |
| id | doaj-art-27f2bf781be54444bc459265dacbdb3e |
| institution | DOAJ |
| issn | 1939-1404 2151-1535 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing |
| spelling | doaj-art-27f2bf781be54444bc459265dacbdb3e2025-08-20T03:13:07ZengIEEEIEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing1939-14042151-15352025-01-01185255527010.1109/JSTARS.2025.353189510854647An Iterative Adaptive Polarization Calibration Method Independent of Corner ReflectorsBowen Chi0https://orcid.org/0000-0001-7139-8608Jixian Zhang1Guoman Huang2Lijun Lu3https://orcid.org/0000-0002-8458-8491Shucheng Yang4https://orcid.org/0009-0008-7240-5011Moganshan Geospatial Information Laboratory, Huzhou, ChinaMoganshan Geospatial Information Laboratory, Huzhou, ChinaChinese Academy of Surveying and Mapping, Beijing, ChinaChinese Academy of Surveying and Mapping, Beijing, ChinaChinese Academy of Surveying and Mapping, Beijing, ChinaPolarimetric calibration (PolCal) is essential for the quantitative processing of polarimetric synthetic aperture radar data. Traditional distributed target methods typically require at least one corner reflector (CR) to determine the copolarization (co-pol) channel imbalance. However, the deployment of CRs is costly and impractical in challenging areas, and therefore, advanced PolCal methods that do not rely on CRs have been developed. One widely used method estimates crosstalk and cross-polarization channel imbalance based on volume-dominated pixels. This method estimates co-pol channel imbalance based on Bragg-like pixels, using the Gauss−Newton method according to the unitary zero helix (UZH) constraint and obtains the final co-pol channel imbalance through fitting. However, the selection of initial values and step sizes affects the convergence of the Gauss−Newton method, while the fixed threshold used in fitting impacts the accuracy of sample selection. These issues collectively influence the precision of the calibration results. Therefore, we proposed an iterative adaptive PolCal method to improve the UZH method from a computational perspective. This method first uses an iterative process to obtain a more accurate global initial value for each block's initial input. It then combined the Levenberg−Marquardt algorithm to adjust step sizes and solve for each block. In addition, the variation coefficient was introduced to achieve adaptive sample selection and enhance fitting accuracy. The effectiveness of our proposed method was validated using GF3 02 satellite two-scene calibration field images. The experiments demonstrated that the proposed method not only ensured convergence but also improved the accuracy and stability of PolCal methods without CRs.https://ieeexplore.ieee.org/document/10854647/Distributed targetspolarimetric calibration (PolCal)polarimetric synthetic aperture radar (PolSAR) |
| spellingShingle | Bowen Chi Jixian Zhang Guoman Huang Lijun Lu Shucheng Yang An Iterative Adaptive Polarization Calibration Method Independent of Corner Reflectors IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Distributed targets polarimetric calibration (PolCal) polarimetric synthetic aperture radar (PolSAR) |
| title | An Iterative Adaptive Polarization Calibration Method Independent of Corner Reflectors |
| title_full | An Iterative Adaptive Polarization Calibration Method Independent of Corner Reflectors |
| title_fullStr | An Iterative Adaptive Polarization Calibration Method Independent of Corner Reflectors |
| title_full_unstemmed | An Iterative Adaptive Polarization Calibration Method Independent of Corner Reflectors |
| title_short | An Iterative Adaptive Polarization Calibration Method Independent of Corner Reflectors |
| title_sort | iterative adaptive polarization calibration method independent of corner reflectors |
| topic | Distributed targets polarimetric calibration (PolCal) polarimetric synthetic aperture radar (PolSAR) |
| url | https://ieeexplore.ieee.org/document/10854647/ |
| work_keys_str_mv | AT bowenchi aniterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT jixianzhang aniterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT guomanhuang aniterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT lijunlu aniterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT shuchengyang aniterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT bowenchi iterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT jixianzhang iterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT guomanhuang iterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT lijunlu iterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors AT shuchengyang iterativeadaptivepolarizationcalibrationmethodindependentofcornerreflectors |