{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T00:59:52Z","timestamp":1769043592201,"version":"3.49.0"},"reference-count":27,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2019,2,27]],"date-time":"2019-02-27T00:00:00Z","timestamp":1551225600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["ESP2015-70014-C2-1-R"],"award-info":[{"award-number":["ESP2015-70014-C2-1-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ag\u00e8ncia de Gesti\u00f3 d\u2019Ajuts Universitaris i de Recerca","award":["FI-DGR 2015"],"award-info":[{"award-number":["FI-DGR 2015"]}]},{"name":"Ag\u00e8ncia de Gesti\u00f3 d\u2019Ajuts Universitaris i de Recerca","award":["Prof. Camps ICREA Academia 2015"],"award-info":[{"award-number":["Prof. Camps ICREA Academia 2015"]}]},{"DOI":"10.13039\/501100004837","name":"Ministerio de Ciencia e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["Unidad de Excelencia Mar\u00eda de Maeztu MDM-2016-0600"],"award-info":[{"award-number":["Unidad de Excelencia Mar\u00eda de Maeztu MDM-2016-0600"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This manuscript describes the Microwave Interferometric Reflectometer (MIR) instrument, a multi-beam dual-band GNSS-Reflectometer with beam-steering capabilities built to assess the performance of a PAssive Reflectrometry and Interferometry System\u2014In Orbit Demonstrator (PARIS-IoD) like instrument and to compare the performance of different GNSS-R techniques and signals. The instrument is capable of tracking up to 4 different GNSS satellites, two at L1\/E1 band, and two at L5\/E5 band. The calibration procedure of the up- and down-looking arrays is presented, the calibration performance is evaluated, and the results of the validation experiments carried out before the field experiments are shown in this paper.<\/jats:p>","DOI":"10.3390\/s19051019","type":"journal-article","created":{"date-parts":[[2019,2,27]],"date-time":"2019-02-27T11:41:03Z","timestamp":1551267663000},"page":"1019","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["The Global Navigation Satellite Systems Reflectometry (GNSS-R) Microwave Interferometric Reflectometer: Hardware, Calibration, and Validation Experiments"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8517-2415","authenticated-orcid":false,"given":"Raul","family":"Onrubia","sequence":"first","affiliation":[{"name":"Remote Sensing Lab (RSLab), Department of Signal Theory and Communications (TSC), Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech (UPC), Jordi Girona 1-3, Campus Nord, D4 Building, 08034 Barcelona, Spain"},{"name":"Institut d\u2019Estudis Espacials de Catalunya (IEEC\/UPC), 08034 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6636-1587","authenticated-orcid":false,"given":"Daniel","family":"Pascual","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab (RSLab), Department of Signal Theory and Communications (TSC), Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech (UPC), Jordi Girona 1-3, Campus Nord, D4 Building, 08034 Barcelona, Spain"},{"name":"Institut d\u2019Estudis Espacials de Catalunya (IEEC\/UPC), 08034 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8500-5534","authenticated-orcid":false,"given":"Jorge","family":"Querol","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab (RSLab), Department of Signal Theory and Communications (TSC), Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech (UPC), Jordi Girona 1-3, Campus Nord, D4 Building, 08034 Barcelona, Spain"},{"name":"Institut d\u2019Estudis Espacials de Catalunya (IEEC\/UPC), 08034 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0031-0802","authenticated-orcid":false,"given":"Hyuk","family":"Park","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab (RSLab), Department of Signal Theory and Communications (TSC), Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech (UPC), Jordi Girona 1-3, Campus Nord, D4 Building, 08034 Barcelona, Spain"},{"name":"Institut d\u2019Estudis Espacials de Catalunya (IEEC\/UPC), 08034 Barcelona, Spain"},{"name":"Physiscs Department, School of Telecommunications and Aerospace Engineering (EETAC), Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech (UPC), 08860 Castelldefels, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9514-4992","authenticated-orcid":false,"given":"Adriano","family":"Camps","sequence":"additional","affiliation":[{"name":"Remote Sensing Lab (RSLab), Department of Signal Theory and Communications (TSC), Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech (UPC), Jordi Girona 1-3, Campus Nord, D4 Building, 08034 Barcelona, Spain"},{"name":"Institut d\u2019Estudis Espacials de Catalunya (IEEC\/UPC), 08034 Barcelona, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hall, C., and Cordey, R. 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