{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:03:47Z","timestamp":1792789427618,"version":"4.5.0"},"reference-count":61,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,22]],"date-time":"2021-02-22T00:00:00Z","timestamp":1613952000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["RTI2018-099008-B-C21 \/ AEI \/ 10.13039\/501100011033"],"award-info":[{"award-number":["RTI2018-099008-B-C21 \/ AEI \/ 10.13039\/501100011033"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["MDM-2016-0600"],"award-info":[{"award-number":["MDM-2016-0600"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002809","name":"Generalitat de Catalunya","doi-asserted-by":"publisher","award":["AGAUR FI-DGR 2018"],"award-info":[{"award-number":["AGAUR FI-DGR 2018"]}],"id":[{"id":"10.13039\/501100002809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Global Navigation Satellite System\u2014Reflectometry (GNSS-R) has already proven its potential for retrieving a number of geophysical parameters, including soil moisture. However, single-pass GNSS-R soil moisture retrieval is still a challenge. This study presents a comparison of two different data sets acquired with the Microwave Interferometer Reflectometer (MIR), an airborne-based dual-band (L1\/E1 and L5\/E5a), multiconstellation (GPS and Galileo) GNSS-R instrument with two 19-element antenna arrays with four electronically steered beams each. The instrument was flown twice over the OzNet soil moisture monitoring network in southern New South Wales (Australia): the first flight was performed after a long period without rain, and the second one just after a rain event. In this work, the impact of surface roughness and vegetation attenuation in the reflectivity of the GNSS-R signal is assessed at both L1 and L5 bands. The work analyzes the reflectivity at different integration times, and finally, an artificial neural network is used to retrieve soil moisture from the reflectivity values. The algorithm is trained and compared to a 20-m resolution downscaled soil moisture estimate derived from SMOS soil moisture, Sentinel-2 normalized difference vegetation index (NDVI) data, and ECMWF Land Surface Temperature.<\/jats:p>","DOI":"10.3390\/rs13040797","type":"journal-article","created":{"date-parts":[[2021,2,22]],"date-time":"2021-02-22T20:42:51Z","timestamp":1614026571000},"page":"797","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["Single-Pass Soil Moisture Retrieval Using GNSS-R at L1 and L5 Bands: Results from Airborne Experiment"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6441-6676","authenticated-orcid":false,"given":"Joan Francesc","family":"Munoz-Martin","sequence":"first","affiliation":[{"name":"CommSensLab\u2014UPC, Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech, and IEEC\/CTE-UPC, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6636-1587","authenticated-orcid":false,"given":"Raul","family":"Onrubia","sequence":"additional","affiliation":[{"name":"CommSensLab\u2014UPC, Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech, and IEEC\/CTE-UPC, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8517-2415","authenticated-orcid":false,"given":"Daniel","family":"Pascual","sequence":"additional","affiliation":[{"name":"CommSensLab\u2014UPC, Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech, and IEEC\/CTE-UPC, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0031-0802","authenticated-orcid":false,"given":"Hyuk","family":"Park","sequence":"additional","affiliation":[{"name":"CommSensLab\u2014UPC, Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech, and IEEC\/CTE-UPC, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2694-7107","authenticated-orcid":false,"given":"Miriam","family":"Pablos","sequence":"additional","affiliation":[{"name":"Physical and Technological Oceanography Group, Consejo Superior de Investigaciones Cient\u00edficas (ICM-CSIC), Centre of Excellence Severo Ochoa, Institut de Ci\u00e8ncies del Mar, Passeig Mar\u00edtim de la Barceloneta 37-49, 08003 Barcelona, Spain"},{"name":"Barcelona Expert Center on Remote Sensing (BEC), Passeig Mar\u00edtim de la Barceloneta 37-49, 08003 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9514-4992","authenticated-orcid":false,"given":"Adriano","family":"Camps","sequence":"additional","affiliation":[{"name":"CommSensLab\u2014UPC, Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech, and IEEC\/CTE-UPC, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4375-4446","authenticated-orcid":false,"given":"Christoph","family":"R\u00fcdiger","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Monash University, Clayton, VIC 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4817-2712","authenticated-orcid":false,"given":"Jeffrey","family":"Walker","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Monash University, Clayton, VIC 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9186-6867","authenticated-orcid":false,"given":"Alessandra","family":"Monerris","sequence":"additional","affiliation":[{"name":"Department of Infrastructure Engineering, The University of Melbourne, Parkville, VIC 3010, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"432","DOI":"10.1016\/j.jhydrol.2019.05.054","article-title":"Influence of changes in rainfall and soil moisture on trends in flooding","volume":"575","author":"Wasko","year":"2019","journal-title":"J. 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