{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:34:54Z","timestamp":1760243694568,"version":"build-2065373602"},"reference-count":15,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2012,8,10]],"date-time":"2012-08-10T00:00:00Z","timestamp":1344556800000},"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>The use of Global Navigation Satellite Systems (GNSS) signals for remote sensing applications, generally referred to as GNSS-Reflectometry (GNSS-R), is gaining increasing interest among the scientific community as a remote sensing tool for land applications. This paper describes a long term experimental campaign in which an extensive dataset of GNSS-R polarimetric measurements was acquired over a crop field from a ground-based stationary platform. Ground truth ancillary data were also continuously recorded during the whole experimental campaign. The duration of the campaign allowed to cover a full crop growing season, and as a consequence of seasonal rains on the experimental area, data could be recorded over a wide variety of soil conditions. This enabled a study on the effects of different land bio-geophysical parameters on GNSS scattered signals. It is shown that significant power variations in the measured GNSS reflected signals can be detected for different soil moisture and vegetation development conditions. In this work we also propose a technique based on the combination of the reflected signal\u2019s polarizations in order to improve the integrity of the observables with respect to nuisance parameters such as soil roughness.<\/jats:p>","DOI":"10.3390\/rs4082356","type":"journal-article","created":{"date-parts":[[2012,8,10]],"date-time":"2012-08-10T11:46:26Z","timestamp":1344599186000},"page":"2356-2372","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":123,"title":["Global Navigation Satellite Systems Reflectometry as a Remote Sensing Tool for Agriculture"],"prefix":"10.3390","volume":"4","author":[{"given":"Alejandro","family":"Egido","sequence":"first","affiliation":[{"name":"Starlab Barcelona, Teodor Roviralta 45, E-08022 Barcelona, Spain"}]},{"given":"Marco","family":"Caparrini","sequence":"additional","affiliation":[{"name":"Starlab Barcelona, Teodor Roviralta 45, E-08022 Barcelona, Spain"}]},{"given":"Giulio","family":"Ruffini","sequence":"additional","affiliation":[{"name":"Starlab Barcelona, Teodor Roviralta 45, E-08022 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3414-4531","authenticated-orcid":false,"given":"Simonetta","family":"Paloscia","sequence":"additional","affiliation":[{"name":"Institute for Applied Physics (IFAC), I-50019 Florence, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1882-6321","authenticated-orcid":false,"given":"Emanuele","family":"Santi","sequence":"additional","affiliation":[{"name":"Institute for Applied Physics (IFAC), I-50019 Florence, Italy"}]},{"given":"Leila","family":"Guerriero","sequence":"additional","affiliation":[{"name":"DISP, Universit`a di Roma Tor Vergata, I-00133 Rome, Italy"}]},{"given":"Nazzareno","family":"Pierdicca","sequence":"additional","affiliation":[{"name":"DIET, Universit`a di Roma La Sapienza, I-00184 Rome, Italy"}]},{"given":"Nicolas","family":"Floury","sequence":"additional","affiliation":[{"name":"European Space Agency (ESA)\/ESTEC, 2201 AZ Noordwijk, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2012,8,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1016\/j.rse.2004.05.016","article-title":"Initial results of land-reflected GPS bistatic radar measurements in SMEX02","volume":"92","author":"Masters","year":"2004","journal-title":"Remote Sens. Environ"},{"unstructured":"Gleason, S. (August, January 31). Detecting Bistatically Reflected GPS Signals from Low Earth Orbit Over Land Surfaces. Denver, CO, USA.","key":"ref_2"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.rse.2005.09.015","article-title":"Utilizing calibrated GPS reflected signals to estimate soil reflectivity and dielectric constant: Results from SMEX02","volume":"100","author":"Katzberg","year":"2006","journal-title":"Remote Sens. Environ"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3252","DOI":"10.1109\/TGRS.2008.921495","article-title":"Radar bistatic configurations for soil moisture retrieval: A simulation study","volume":"46","author":"Pierdicca","year":"2008","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1109\/JSTARS.2009.2033612","article-title":"GPS multipath and its relation to near-surface soil moisture content","volume":"3","author":"Larson","year":"2010","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1109\/JSTARS.2009.2033608","article-title":"A physical model for GPS multipath caused by land reflections: Toward bare soil moisture retrievals","volume":"3","author":"Zavorotny","year":"2010","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1109\/TGRS.2010.2049023","article-title":"Land geophysical parameters retrieval using the interference pattern GNSS-R technique","volume":"49","author":"Camps","year":"2011","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1823","DOI":"10.1016\/j.asr.2010.04.025","article-title":"Forest biomass monitoring with GNSS-R: Theoretical simulations","volume":"47","author":"Ferrazzoli","year":"2011","journal-title":"Adv. Space Res"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1272","DOI":"10.3390\/rs4051272","article-title":"Review of the CALIMAS team contributions to european space agency\u2019s soil moisture and ocean salinity mission calibration and validation","volume":"4","author":"Camps","year":"2012","journal-title":"Remote Sens"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"951","DOI":"10.1109\/36.841977","article-title":"Scattering of GPS signals from the ocean with wind remote sensing application","volume":"38","author":"Zavorotny","year":"2000","journal-title":"IEEE Trans. Geosci. 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Antennas and Radiowave Propagation, McGraw-Hill.","key":"ref_14"},{"unstructured":"Ballanis, C.A. (2005). Antenna Theory-Analysis and Design, Wiley Interscience. [3rd ed].","key":"ref_15"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/4\/8\/2356\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:51:44Z","timestamp":1760219504000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/4\/8\/2356"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,8,10]]},"references-count":15,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2012,8]]}},"alternative-id":["rs4082356"],"URL":"https:\/\/doi.org\/10.3390\/rs4082356","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2012,8,10]]}}}