Accelerated algorithm for back-projection fully focused SAR altimetry
Fully focused synthetic aperture radar (SAR) back-projection algorithms for radar altimetry have gained attention in the altimetry community due to their improved azimuth resolution compared to traditional methods, such as the delay/Doppler algorithm. However, the significant computational cost of b...
| Autores: | , , , , , , , |
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| Tipo de documento: | artigo |
| Data de publicação: | 2025 |
| País: | España |
| Recursos: | Universitat Politècnica de Catalunya (UPC) |
| Repositório: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglês |
| OAI Identifier: | oai:upcommons.upc.edu:2117/429000 |
| Acesso em linha: | https://hdl.handle.net/2117/429000 https://dx.doi.org/10.1109/TGRS.2025.3556544 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Accelerated algorithm Accelerated backprojection Back-projection Delay/Doppler Fully focused (FF) Fully focused synthetic aperture radar (FF-SAR) GPU acceleration High-resolution radar altimetry Omega-K Open ocean Radar altimetry Real time altimetry Synthetic aperture radar (SAR) Transponder Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Radiocomunicació i exploració electromagnètica::Radar |
| Resumo: | Fully focused synthetic aperture radar (SAR) back-projection algorithms for radar altimetry have gained attention in the altimetry community due to their improved azimuth resolution compared to traditional methods, such as the delay/Doppler algorithm. However, the significant computational cost of back-projection has limited its use in operational applications. This paper presents an accelerated back-projection algorithm that reduces the runtime of the classic back-projection by a factor of 28 on a CPU-based architecture. When implemented on a GPU-based architecture, the accelerated back-projection achieves a speedup ranging from 8 to 13 times compared to the classic back-projection on the same GPU. In comparison to the classic back-projection running on a CPU, the combination of the accelerated back-projection and GPU processing results in an overall improvement of up to 1570 times. The accelerated algorithm maintains the accuracy of classic time-domain algorithms, and allows to process data in the order of the sensing time under a GPU-based architecture. The algorithm has been extensively validated using transponder and open ocean data. These results indicate that operational back-projection algorithms are feasible for current radar altimetry missions, such as Sentinel-6, and upcoming missions like CRISTAL and Sentinel-3 Next Generation. |
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