{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,12]],"date-time":"2026-04-12T11:11:43Z","timestamp":1775992303669,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,12,26]],"date-time":"2018-12-26T00:00:00Z","timestamp":1545782400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This paper assesses the potential of Synthetic Aperture Radar (SAR) in the C and L bands to penetrate into the canopy cover of wheat, maize and grasslands. For wheat and grasslands, the sensitivity of the C and L bands to in situ surface soil moisture (SSM) was first studied according to three levels of the Normalized Difference Vegetation Index (NDVI &lt; 0.4, 0.4 &lt; NDVI &lt; 0.7, and NDVI &gt; 0.7). Next, the temporal evolution of the SAR signal in the C and L bands was analyzed according to SSM and the NDVI. For wheat and grasslands, the results showed that the L-band in HH polarization penetrates the canopy even when the canopy is well-developed (NDVI &gt; 0.7), whereas the penetration of the C-band into the canopy is limited for an NDVI &lt; 0.7. For an NDVI less than 0.7, the sensitivity of the radar signal to SSM is approximately 0.27 dB\/vol.% for the L-band in HH polarization and approximately 0.12 dB\/vol.% for the C-band (in both VV and VH polarizations). For highly developed wheat and grassland cover (NDVI &gt; 0.7), the sensitivity of the L-band in HH polarization to SSM is approximately 0.19 dB\/vol.%, whereas as the C-band is insensitive to SSM. For maize, only the temporal evolution of the C-band according to SSM and the NDVI was studied because the swath of SAR images in the L-band did not cover the maize plots. The results showed that the C-band in VV polarization is able to penetrate the maize canopy even when the canopy is well developed (NDVI &gt; 0.7) due to high-order scattering along the soil-vegetation pathway that contains a soil contribution. According to results obtained in this paper, the L-band would penetrate a well-developed maize cover since the penetration depth of the L-band is greater than that of the C-band.<\/jats:p>","DOI":"10.3390\/rs11010031","type":"journal-article","created":{"date-parts":[[2018,12,26]],"date-time":"2018-12-26T11:31:21Z","timestamp":1545823881000},"page":"31","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":137,"title":["Penetration Analysis of SAR Signals in the C and L Bands for Wheat, Maize, and Grasslands"],"prefix":"10.3390","volume":"11","author":[{"given":"Mohammad","family":"El Hajj","sequence":"first","affiliation":[{"name":"IRSTEA, TETIS, University of Montpellier, 34093 Montpellier, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9461-4120","authenticated-orcid":false,"given":"Nicolas","family":"Baghdadi","sequence":"additional","affiliation":[{"name":"IRSTEA, TETIS, University of Montpellier, 34093 Montpellier, France"}]},{"given":"Hassan","family":"Bazzi","sequence":"additional","affiliation":[{"name":"IRSTEA, TETIS, University of Montpellier, 34093 Montpellier, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6141-8222","authenticated-orcid":false,"given":"Mehrez","family":"Zribi","sequence":"additional","affiliation":[{"name":"CESBIO (CNRS\/UPS\/IRD\/CNES), 31401 Toulouse, France"}]}],"member":"1968","published-online":{"date-parts":[[2018,12,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"79","DOI":"10.2478\/v10025-000-0007-0","article-title":"Irrigation management by means of soil moisture sensor technologies","volume":"11","author":"Cepuder","year":"2007","journal-title":"J. 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