{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:40:26Z","timestamp":1760222426660,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2010,12,30]],"date-time":"2010-12-30T00:00:00Z","timestamp":1293667200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This paper presents the description and performance tests of an L-band microwave radiometer with Digital Beamforming (DBF), developed for the Passive Advanced Unit (PAU) for ocean monitoring project. PAU is an instrument that combines, in a single receiver and without time multiplexing, a microwave radiometer at L-band (PAU-RAD) and a GPS-reflectometer (PAU-GNSS-R). This paper focuses on the PAU\u2011RAD beamformer\u2019s first results, analyzing the hardware and software required for the developed prototype. Finally, it discusses the first results measured in the Universitat Polit\u00e8cnica de Catalunya (UPC) anechoic chamber.<\/jats:p>","DOI":"10.3390\/rs3010014","type":"journal-article","created":{"date-parts":[[2010,12,30]],"date-time":"2010-12-30T10:33:15Z","timestamp":1293705195000},"page":"14-40","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Description and Performance of an L-Band Radiometer with Digital Beamforming"],"prefix":"10.3390","volume":"3","author":[{"given":"Xavier","family":"Bosch-Lluis","sequence":"first","affiliation":[{"name":"Remote Sensing Lab, Department of Signal Theory and Communications, Technical University of Catalonia, Diagonal North Campus, and IEEC CRAE\/UPC, Jordi Girona 1-3, Building D4, 08034 Barcelona, Spain"}]},{"given":"Isaac","family":"Ramos-Perez","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab, Department of Signal Theory and Communications, Technical University of Catalonia, Diagonal North Campus, and IEEC CRAE\/UPC, Jordi Girona 1-3, Building D4, 08034 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9514-4992","authenticated-orcid":false,"given":"Adriano","family":"Camps","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab, Department of Signal Theory and Communications, Technical University of Catalonia, Diagonal North Campus, and IEEC CRAE\/UPC, Jordi Girona 1-3, Building D4, 08034 Barcelona, Spain"}]},{"given":"Nereida","family":"Rodriguez-Alvarez","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab, Department of Signal Theory and Communications, Technical University of Catalonia, Diagonal North Campus, and IEEC CRAE\/UPC, Jordi Girona 1-3, Building D4, 08034 Barcelona, Spain"}]},{"given":"Enric","family":"Valencia","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab, Department of Signal Theory and Communications, Technical University of Catalonia, Diagonal North Campus, and IEEC CRAE\/UPC, Jordi Girona 1-3, Building D4, 08034 Barcelona, Spain"}]},{"given":"Juan F.","family":"Marchan-Hernandez","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab, Department of Signal Theory and Communications, Technical University of Catalonia, Diagonal North Campus, and IEEC CRAE\/UPC, Jordi Girona 1-3, Building D4, 08034 Barcelona, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2010,12,30]]},"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":"Barre","year":"2008","journal-title":"IEEE Trans. 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