{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,5]],"date-time":"2026-02-05T10:30:05Z","timestamp":1770287405421,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,15]],"date-time":"2021-11-15T00:00:00Z","timestamp":1636934400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002923","name":"Consejo Nacional de Investigaciones Cient\u00edficas y T\u00e9cnicas","doi-asserted-by":"publisher","award":["PICT 2015 N\u25e63689"],"award-info":[{"award-number":["PICT 2015 N\u25e63689"]}],"id":[{"id":"10.13039\/501100002923","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004837","name":"Ministerio de Ciencia e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["CICYT RTI2018-099008-B-C21\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["CICYT RTI2018-099008-B-C21\/AEI\/10.13039\/501100011033"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["Excellence Research Unit Maria de Maeztu"],"award-info":[{"award-number":["Excellence Research Unit Maria de Maeztu"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This research aims at modeling the microwave backscatter of corn fields by coupling an incoherent, interaction-based scattering model with a semi-empirical bulk vegetation dielectric model. The scattering model is fitted to co-polarized phase difference measurements over several corn fields imaged with fully polarimetric synthetic aperture radar (SAR) images with incidence angles ranging from 20\u00b0 to 60\u00b0. The dataset comprised two field campaigns, one over Canada with the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR, 1.258 GHz) and the other one over Argentina with Advanced Land Observing Satellite 2 (ALOS-2) Phased Array type L-band Synthetic Aperture Radar (PALSAR-2) (ALOS-2\/PALSAR-2, 1.236 GHz), totaling 60 data measurements over 28 grown corn fields at peak biomass with stalk gravimetric moisture larger than 0.8 g\/g. Co-polarized phase differences were computed using a maximum likelihood estimation technique from each field\u2019s measured speckled sample histograms. After minimizing the difference between the model and data measurements for varying incidence angles by a nonlinear least-squares fitting, well agreement was found with a root mean squared error of 24.3\u00b0 for co-polarized phase difference measurements in the range of \u2212170.3\u00b0 to \u221219.13\u00b0. Model parameterization by stalk gravimetric moisture instead of its complex dielectric constant is also addressed. Further validation was undertaken for the UAVSAR dataset on earlier corn stages, where overall sensitivity to stalk height, stalk gravimetric moisture, and stalk area density agreed with ground data, with the sensitivity to stalk diameter being the weakest. This study provides a new perspective on the use of co-polarized phase differences in retrieving corn stalk features through inverse modeling techniques from space.<\/jats:p>","DOI":"10.3390\/rs13224593","type":"journal-article","created":{"date-parts":[[2021,11,15]],"date-time":"2021-11-15T20:46:47Z","timestamp":1637009207000},"page":"4593","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["L-Band SAR Co-Polarized Phase Difference Modeling for Corn Fields"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6947-4293","authenticated-orcid":false,"given":"Mat\u00edas Ernesto","family":"Barber","sequence":"first","affiliation":[{"name":"Quantitative Remote Sensing Group, Institute of Astronomy and Space Physics (IAFE), Buenos Aires 1428, Argentina"},{"name":"Department of Physics, Engineering School, University of Buenos Aires (UBA), Buenos Aires 1428, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David Sebasti\u00e1n","family":"Rava","sequence":"additional","affiliation":[{"name":"Quantitative Remote Sensing Group, Institute of Astronomy and Space Physics (IAFE), Buenos Aires 1428, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1366-9446","authenticated-orcid":false,"given":"Carlos","family":"L\u00f3pez-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Signal Theory and Communications Department (TSC), Universitat Polit\u00e8cnica de Catalunya (UPC), 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"525","DOI":"10.5589\/m03-069","article-title":"The application of C-band polarimetric SAR for agriculture: A review","volume":"30","author":"McNairn","year":"2004","journal-title":"Can. 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