{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T06:02:00Z","timestamp":1769925720803,"version":"3.49.0"},"reference-count":48,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,1,31]],"date-time":"2023-01-31T00:00:00Z","timestamp":1675123200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"French National Research Council (CNRS)"},{"name":"French Space Agency (CNES)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>For almost five years, phase 0 and phase A studies have been conducted by the French space agency for a second generation of the Soil Moisture and Ocean Salinity (SMOS) satellite devoted to a High Resolution (HR) follow-on mission. Within the frame of the preliminary results obtained with a candidate array for this SMOS-HR project, this contribution focuses on what could happen to any synthetic aperture imaging radiometer when the shortest spacing between the antennas of the interferometric array becomes smaller than a geometrical limit below which the synthesized field of view seems to be wider than the field of view seen by each elementary antenna. It is shown that in such a situation, the inversion of the complex visibilities becomes unstable in presence of noise and this instability is characterized by the undesirable presence of a phantom in the retrieved brightness temperature maps. The origin of this phantom is explained and a solution to cure the interferometric array from that issue is proposed and assessed with the aid of numerical simulations.<\/jats:p>","DOI":"10.3390\/rs15030805","type":"journal-article","created":{"date-parts":[[2023,2,1]],"date-time":"2023-02-01T05:33:53Z","timestamp":1675229633000},"page":"805","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Impact of the Antenna Spacing on the Brightness Temperature Maps Retrieved with a Synthetic Aperture Imaging Radiometer"],"prefix":"10.3390","volume":"15","author":[{"given":"Eric","family":"Anterrieu","sequence":"first","affiliation":[{"name":"Centre d\u2019\u00c9tudes Spatiales de la BIOsph\u00e8re (CESBIO), 13 Avenue Colonel Roche, 31400 Toulouse, France"}]},{"given":"Louise","family":"Yu","sequence":"additional","affiliation":[{"name":"Centre National d\u2019\u00c9tudes Spatiales (CNES), 18 Avenue Edouard Belin, 31400 Toulouse, France"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"587","DOI":"10.1109\/TGRS.2008.916264","article-title":"SMOS: The Mission and the System","volume":"46","author":"Duesmann","year":"2008","journal-title":"IEEE Trans. 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