A field test of compact active transponders for InSAR geodesy
Compact active transponders (CATs) – also termed electronic corner reflectors – are compact electronic devices designed to receive, actively amplify and re-transmit a radar signal, e.g. a C-band radar signal received from a Sentinel-1 satellite. CATs can potentially be useful for a number of purpose...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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De Gruyter
2024-01-01
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| Series: | Journal of Geodetic Science |
| Subjects: | |
| Online Access: | https://doi.org/10.1515/jogs-2022-0164 |
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| author | Meister A. Balasis-Levinsen J. Keller K. Pedersen M. R. V. Merryman Boncori J. P. Jensen M. |
| author_facet | Meister A. Balasis-Levinsen J. Keller K. Pedersen M. R. V. Merryman Boncori J. P. Jensen M. |
| author_sort | Meister A. |
| collection | DOAJ |
| description | Compact active transponders (CATs) – also termed electronic corner reflectors – are compact electronic devices designed to receive, actively amplify and re-transmit a radar signal, e.g. a C-band radar signal received from a Sentinel-1 satellite. CATs can potentially be useful for a number of purposes, e.g. if co-located with geodetic infrastructure. However, CATs have only recently become commercially available, and therefore, the usability and long-term performance of CATs are not well known. In this study, two CATs are tested under realistic operating conditions for a period of 14 months, from July 2020 to September 2021. The displacement time series of the CATs are determined from a persistent scatterers interferometric synthetic aperture radar processing of four tracks of Sentinel-1A/-1B data with a passive corner reflector (CR) as the spatial reference. The displacement time series of the CATs are evaluated against a ground truth established from repeated levellings between the CR and the CATs. Based on the results of this study, it is found that a sudden vertical displacement of a CAT can be determined with an accuracy better than 1 cm, possibly a few millimetres. Furthermore, it is found that the mean vertical velocity of a CAT, calculated from 14 months of interferometric synthetic aperture radar displacement time series, can be determined with an accuracy of a few mm/year. Finally, the line of sight (LoS) phase error is generally found to be moderately correlated with temperature, with an instrument-specific linear relationship between LoS error and temperature ranging between approx. 0.1 and 0.2 mm/°C. This correlation between LoS phase error and temperature can in principle be used for instrument-specific calibrations, which is a topic that should be addressed in future studies. |
| first_indexed | 2024-03-08T10:10:48Z |
| format | Article |
| id | doaj.art-7073cd5998e843f497a67f7201a7ba18 |
| institution | Directory Open Access Journal |
| issn | 2081-9943 |
| language | English |
| last_indexed | 2024-03-08T10:10:48Z |
| publishDate | 2024-01-01 |
| publisher | De Gruyter |
| record_format | Article |
| series | Journal of Geodetic Science |
| spelling | doaj.art-7073cd5998e843f497a67f7201a7ba182024-01-29T08:48:27ZengDe GruyterJournal of Geodetic Science2081-99432024-01-01141pp. 3293610.1515/jogs-2022-0164A field test of compact active transponders for InSAR geodesyMeister A.0Balasis-Levinsen J.1Keller K.2Pedersen M. R. V.3Merryman Boncori J. P.4Jensen M.5Agency for Data Supply and Infrastructure, Ministry of Climate, Energy and Utilities, Sankt Kjelds Plads 11, 2100 Copenhagen Ø, DenmarkAgency for Data Supply and Infrastructure, Ministry of Climate, Energy and Utilities, Sankt Kjelds Plads 11, 2100 Copenhagen Ø, DenmarkAgency for Data Supply and Infrastructure, Ministry of Climate, Energy and Utilities, Sankt Kjelds Plads 11, 2100 Copenhagen Ø, DenmarkAgency for Data Supply and Infrastructure, Ministry of Climate, Energy and Utilities, Sankt Kjelds Plads 11, 2100 Copenhagen Ø, DenmarkDTU Space, Technical University of Denmark, Elektrovej, Building 327, 2800 Kongens Lyngby, DenmarkAgency for Data Supply and Infrastructure, Ministry of Climate, Energy and Utilities, Sankt Kjelds Plads 11, 2100 Copenhagen Ø, DenmarkCompact active transponders (CATs) – also termed electronic corner reflectors – are compact electronic devices designed to receive, actively amplify and re-transmit a radar signal, e.g. a C-band radar signal received from a Sentinel-1 satellite. CATs can potentially be useful for a number of purposes, e.g. if co-located with geodetic infrastructure. However, CATs have only recently become commercially available, and therefore, the usability and long-term performance of CATs are not well known. In this study, two CATs are tested under realistic operating conditions for a period of 14 months, from July 2020 to September 2021. The displacement time series of the CATs are determined from a persistent scatterers interferometric synthetic aperture radar processing of four tracks of Sentinel-1A/-1B data with a passive corner reflector (CR) as the spatial reference. The displacement time series of the CATs are evaluated against a ground truth established from repeated levellings between the CR and the CATs. Based on the results of this study, it is found that a sudden vertical displacement of a CAT can be determined with an accuracy better than 1 cm, possibly a few millimetres. Furthermore, it is found that the mean vertical velocity of a CAT, calculated from 14 months of interferometric synthetic aperture radar displacement time series, can be determined with an accuracy of a few mm/year. Finally, the line of sight (LoS) phase error is generally found to be moderately correlated with temperature, with an instrument-specific linear relationship between LoS error and temperature ranging between approx. 0.1 and 0.2 mm/°C. This correlation between LoS phase error and temperature can in principle be used for instrument-specific calibrations, which is a topic that should be addressed in future studies.https://doi.org/10.1515/jogs-2022-0164artificial radar reflectorcatcompact active transponderecrelectronic corner reflectorfield testinsarinsar geodesyinterferometric synthetic aperture radarsentinel-1 |
| spellingShingle | Meister A. Balasis-Levinsen J. Keller K. Pedersen M. R. V. Merryman Boncori J. P. Jensen M. A field test of compact active transponders for InSAR geodesy Journal of Geodetic Science artificial radar reflector cat compact active transponder ecr electronic corner reflector field test insar insar geodesy interferometric synthetic aperture radar sentinel-1 |
| title | A field test of compact active transponders for InSAR geodesy |
| title_full | A field test of compact active transponders for InSAR geodesy |
| title_fullStr | A field test of compact active transponders for InSAR geodesy |
| title_full_unstemmed | A field test of compact active transponders for InSAR geodesy |
| title_short | A field test of compact active transponders for InSAR geodesy |
| title_sort | field test of compact active transponders for insar geodesy |
| topic | artificial radar reflector cat compact active transponder ecr electronic corner reflector field test insar insar geodesy interferometric synthetic aperture radar sentinel-1 |
| url | https://doi.org/10.1515/jogs-2022-0164 |
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