{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T17:24:11Z","timestamp":1778693051952,"version":"3.51.4"},"reference-count":21,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2015,7,22]],"date-time":"2015-07-22T00:00:00Z","timestamp":1437523200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Sentinel-1A (S1A) is an Earth observation satellite carrying a state-of-the-art Synthetic Aperture Radar (SAR) imaging instrument. It was launched by the European Space Agency (ESA) on 3 April 2014. With the end of the in-orbit commissioning phase having been completed at the end of September 2014, S1A data products are already consistently providing highly accurate geolocation. StripMap (SM) mode products were acquired regularly and tested for geolocation accuracy and consistency during dedicated corner reflector (CR) campaigns. At the completion of this phase, small geometric inconsistencies had been understood and mitigated, with the high quality of the final product geolocation estimates reflecting the mission\u2019s success thus far. This paper describes the measurement campaign, the methods used during geolocation estimation, and presents best estimates of the product Absolute Location Error (ALE) available at the beginning of S1A\u2019s operational phase.<\/jats:p>","DOI":"10.3390\/rs70709431","type":"journal-article","created":{"date-parts":[[2015,7,22]],"date-time":"2015-07-22T08:45:40Z","timestamp":1437554740000},"page":"9431-9449","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":93,"title":["Sentinel-1A Product Geolocation Accuracy: Commissioning Phase Results"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8701-8144","authenticated-orcid":false,"given":"Adrian","family":"Schubert","sequence":"first","affiliation":[{"name":"Remote Sensing Laboratories, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1440-364X","authenticated-orcid":false,"given":"David","family":"Small","sequence":"additional","affiliation":[{"name":"Remote Sensing Laboratories, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nuno","family":"Miranda","sequence":"additional","affiliation":[{"name":"ESA-ESRIN, Via Galileo Galilei, 00044 Frascati, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dirk","family":"Geudtner","sequence":"additional","affiliation":[{"name":"ESA-ESTEC, Keplerlaan 1, 2200 AG Noordwijk, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Erich","family":"Meier","sequence":"additional","affiliation":[{"name":"Remote Sensing Laboratories, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,7,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3081","DOI":"10.1109\/TGRS.2011.2120616","article-title":"Flattening gamma: Radiometric terrain correction for SAR imagery","volume":"49","author":"Small","year":"2011","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_2","unstructured":"Aulard-Macler, M. (2012). Sentinel-1 Product Definition, MacDonald, Dettwiler and Associates (MDA). MDA Technical Note Ref. S1-RS-MDA-52-7440."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Schubert, A., Small, D., Meier, E., Miranda, N., and Geudtner, D. (2014, January 13\u201318). Spaceborne SAR product geolocation accuracy\u202f: A Sentinel-1 update. 2014 IEEE International Geoscience and Remote Sensing Symposium (IGARSS 2014), Quebec City, QC, Canada.","DOI":"10.1109\/IGARSS.2014.6947025"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Geudtner, D., Torres, R., Snoeij, P., Davidson, M., and Rommen, B. (2014, January 13\u201318). Sentinel-1 system capabilities and applications. Proceedings of the 2014 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Quebec City, QC, Canada.","DOI":"10.1109\/IGARSS.2014.6946711"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1016\/j.rse.2011.05.028","article-title":"GMES Sentinel-1 mission","volume":"120","author":"Torres","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"751","DOI":"10.1109\/TGRS.2009.2036252","article-title":"Influence of atmospheric path delay on the absolute geolocation accuracy of TerraSAR-X high-resolution products","volume":"48","author":"Schubert","year":"2010","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1007\/s00190-011-0515-6","article-title":"Mitigation of atmospheric perturbations and solid Earth movements in a TerraSAR-X time-series","volume":"86","author":"Schubert","year":"2012","journal-title":"J. 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