{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T17:17:49Z","timestamp":1767892669170,"version":"3.49.0"},"reference-count":18,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,3,18]],"date-time":"2021-03-18T00:00:00Z","timestamp":1616025600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000844","name":"European Space Agency","doi-asserted-by":"publisher","award":["ALR-RP-0017-TA"],"award-info":[{"award-number":["ALR-RP-0017-TA"]}],"id":[{"id":"10.13039\/501100000844","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["TEC2017-88850-R"],"award-info":[{"award-number":["TEC2017-88850-R"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In the frame of an SMOS follow-on operational mission, a new instrument design is being developed based on the lessons learned from MIRAS, the SMOS payload. To reduce hardware complexity and mass, digital In-phase Quadrature (IQ) demodulation is considered. In this schema, Q components are obtained by delaying one clock of the digitized IF signals instead of using phase quadrature analog mixers. The purpose of this article is to formulate this concept for application to interferometric radiometry, establish the required data processing methods, and provide experimental results.<\/jats:p>","DOI":"10.3390\/rs13061156","type":"journal-article","created":{"date-parts":[[2021,3,18]],"date-time":"2021-03-18T02:42:05Z","timestamp":1616035325000},"page":"1156","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Novel Digital IQ Demodulation for Interferometric Radiometers"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5598-7955","authenticated-orcid":false,"given":"Ignasi","family":"Corbella","sequence":"first","affiliation":[{"name":"Remote Sensing Laboratory, Universitat Polit\u00e8cnica de Catalunya, c\/ Jordi Girona 1-3, 08034 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7626-7033","authenticated-orcid":false,"given":"Manuel","family":"Mart\u00edn Neira","sequence":"additional","affiliation":[{"name":"European Space Research and Technology Centre, European Space Agency, 2200 AG Noordwijk, The Netherlands"}]},{"given":"Roger","family":"Vilaseca","sequence":"additional","affiliation":[{"name":"SENER TAFS S.A.U. Parc de l\u2019 Alba, C\/ Creu Casas i Sicart, 86-87, 08290 Cerdanyola del Vall\u00e8s, Spain"}]},{"given":"Albert","family":"Catalan","sequence":"additional","affiliation":[{"name":"SENER TAFS S.A.U. 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Proceedings of the International Geoscience and Remote Sensing Symposium, IGARSS 2005, Seoul, Korea.","DOI":"10.1109\/IGARSS.2006.1020"},{"key":"ref_17","unstructured":"Corbella, I., Torres, F., Camps, A., Bar\u00e1, J., Duffo, N., and Vall-llossera, M. (2000, January 24\u201328). L-band aperture synthesis radiometry: Hardware requirements and system performance. Proceedings of the International Geoscience and Remote Sensing Symposium, IGARSS 2000, Honolulu, HI, USA."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"646","DOI":"10.1109\/TGRS.2007.914810","article-title":"SMOS calibration","volume":"46","author":"Brown","year":"2008","journal-title":"IEEE Trans. Geosci. 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