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Soil and vegetation scattering contributions in L-Band and P-Band polarimetric SAR observations / S. Hamed Alemohammad in IEEE Transactions on geoscience and remote sensing, vol 57 n° 11 (November 2019)
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Titre : Soil and vegetation scattering contributions in L-Band and P-Band polarimetric SAR observations Type de document : Article/Communication Auteurs : S. Hamed Alemohammad, Auteur ; Thomas Jagdhuber, Auteur ; Mahta Moghaddam, Auteur ; Dara Entekhabi, Auteur Année de publication : 2019 Article en page(s) : pp 8417 - 8429 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes descripteurs IGN] bande L
[Termes descripteurs IGN] bande P
[Termes descripteurs IGN] canopée
[Termes descripteurs IGN] constante diélectrique
[Termes descripteurs IGN] couvert végétal
[Termes descripteurs IGN] données polarimétriques
[Termes descripteurs IGN] humidité du sol
[Termes descripteurs IGN] image captée par drone
[Termes descripteurs IGN] image radar moirée
[Termes descripteurs IGN] micro-onde
[Termes descripteurs IGN] rugosité du sol
[Termes descripteurs IGN] teneur en eau de la végétationRésumé : (auteur) Active microwave-based retrieval of soil moisture in vegetated areas has uncertainties due to the sensitivity of the signal to both soil (dielectric constant and roughness) and vegetation (dielectric constant and structure) properties. A multi-frequency acquisition system would increase the number of observations that may constrain soil and/or vegetation parameter retrievals. In order to realize this constraint, an understanding of microwaves interaction with the surface and vegetation across frequencies is necessary. Different microwave frequencies have varied interactions with the soil-vegetation medium and increasing penetration into the soil and canopy with the decreasing frequency. In this study, we examine the contributions of different scattering mechanisms to coincident observations from two microwave frequencies (L and P) of airborne synthetic aperture radar instruments. We quantify contributions of surface, vegetation volume, and double-bounce scattering components. Results are analyzed and discussed to guide future multi-frequency retrieval algorithm designs. Numéro de notice : A2019-594 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2019.2920995 date de publication en ligne : 27/06/2019 En ligne : https://doi.org/10.1109/TGRS.2019.2920995 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94586
in IEEE Transactions on geoscience and remote sensing > vol 57 n° 11 (November 2019) . - pp 8417 - 8429[article]Polarization orientation angle and polarimetric SAR scattering characteristics of steep terrain / Jong-Sen Lee in IEEE Transactions on geoscience and remote sensing, vol 56 n° 12 (December 2018)
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Titre : Polarization orientation angle and polarimetric SAR scattering characteristics of steep terrain Type de document : Article/Communication Auteurs : Jong-Sen Lee, Auteur ; Thomas L. Ainsworth, Auteur ; Yanting Wang, Auteur Année de publication : 2018 Article en page(s) : pp 7272 - 7281 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes descripteurs IGN] angle de visée
[Termes descripteurs IGN] bande C
[Termes descripteurs IGN] bande L
[Termes descripteurs IGN] constante diélectrique
[Termes descripteurs IGN] données polarimétriques
[Termes descripteurs IGN] escarpement
[Termes descripteurs IGN] humidité du sol
[Termes descripteurs IGN] image radar moirée
[Termes descripteurs IGN] image TOPSAR
[Termes descripteurs IGN] modèle de diffusion du rayonnement
[Termes descripteurs IGN] montagne
[Termes descripteurs IGN] pente
[Termes descripteurs IGN] polarimétrie radar
[Termes descripteurs IGN] polarisation croisée
[Termes descripteurs IGN] réflectance spectrale
[Termes descripteurs IGN] rétrodiffusion de Bragg
[Termes descripteurs IGN] teneur en eau de la végétationRésumé : (auteur) Polarization orientation angle (POA) is an important parameter of polarimetric radar scattering from slopes in mountainous region. It is known that surface tilted in azimuth direction and buildings not aligned in the along-track direction induce polarization orientation shifts. Earlier research has established orientation angle as a function of radar imaging geometry and surface slopes, and that POA estimation can be derived from polarimetric radar data using circular polarization. Besides these, polarimetric scattering from steep slopes and its relation to POA remain not well understood. In this paper, we address these issues by adopting a tilted surface model based on Bragg scattering. We have found that, as the azimuthal slope increases, |VV| decreases at a faster rate than |HH|, they become equal, when POA is ±45°, and |HH| > |VV| afterward. In other words, the Pauli component, |HH-VV| reduced to zero at POA = ± 45°, and the typical Bragg scattering characteristics of |VV| > |HH| does not apply when steep slope is present inducing |POA| > 45°. Furthermore, the cross-pol |HV| does not always increase with azimuth slope but also reaches a maximum then decreases to zero. In addition, we investigate the effect of soil moisture on polarimetric SAR (PolSAR) scattering characteristics of steep terrain and the effect of vegetation over surface on POA estimation. The latter is demonstrated with NASA/JPL TOPSAR L-band PolSAR data and C-band InSAR data. Another significance of this paper is that it provides a direct and rigorous derivation of POA equations. The earlier version was derived from a different concept. Numéro de notice : A2018-557 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2018.2849931 date de publication en ligne : 01/08/2018 En ligne : http://dx.doi.org/10.1109/TGRS.2018.2849931 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91662
in IEEE Transactions on geoscience and remote sensing > vol 56 n° 12 (December 2018) . - pp 7272 - 7281[article]Measure of temporal variation of P-Band radar cross section and temporal coherence of a temperate tree / Clément Albinet in IEEE Transactions on geoscience and remote sensing, vol 54 n° 11 (November 2016)
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Titre : Measure of temporal variation of P-Band radar cross section and temporal coherence of a temperate tree Type de document : Article/Communication Auteurs : Clément Albinet, Auteur ; Pierre Borderies, Auteur ; Nicolas Floury, Auteur ; Eric Pottier, Auteur Année de publication : 2016 Article en page(s) : pp 6255 - 6264 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes descripteurs IGN] bande P
[Termes descripteurs IGN] Cedrus (genre)
[Termes descripteurs IGN] constante diélectrique
[Termes descripteurs IGN] diffusomètre
[Termes descripteurs IGN] polarimétrie radar
[Termes descripteurs IGN] surface équivalente radarRésumé : (Auteur) This paper deals with a ground experiment based on a P-band scatterometer that measured the evolution of the radar cross section (RCS) and coherence of a temperate tree in HV polarization, during four periods spread over nine months, over a cedar tree. Watering of the tree has limited influence in time on the RCS, i.e., limited to around 30 min, but impacts the coherence over a longer period of time. Analysis of the series shows that according to the season considered, clear daily cycles from 1 to 2 dB may appear on the coherence only (autumn) or on both coherence and RCS (spring), whereas in winter, they are absent on both results. It was analyzed in the literature that the variations in RCS are strongly correlated to the variations in the dielectric constant in trunks and branches. In addition, it was shown that the HV RCS presents seasonal trends with a yearly cycle of roughly 3 dB following similar trends reported for trunk moisture content time series. Numéro de notice : A2016-910 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern En ligne : http://dx.doi.org/10.1109/TGRS.2016.2565384 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83132
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 11 (November 2016) . - pp 6255 - 6264[article]Multitemporal fluctuations in L-Band Backscatter from a japanese forest / Manabu Watanabe in IEEE Transactions on geoscience and remote sensing, vol 53 n° 11 (November 2015)
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Titre : Multitemporal fluctuations in L-Band Backscatter from a japanese forest Type de document : Article/Communication Auteurs : Manabu Watanabe, Auteur ; Takeshi Motohka, Auteur ; Tomohiro Shiraishi, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 5799 - 5813 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes descripteurs IGN] bande L
[Termes descripteurs IGN] biomasse forestière
[Termes descripteurs IGN] coefficient de rétrodiffusion
[Termes descripteurs IGN] constante diélectrique
[Termes descripteurs IGN] données multitemporelles
[Termes descripteurs IGN] forêt
[Termes descripteurs IGN] image ALOS
[Termes descripteurs IGN] image radar moirée
[Termes descripteurs IGN] JaponRésumé : (Auteur) The temporal variations (diurnal and annual) in arboreal (εTree) and bare soil (εSoil) dielectric constants and their correlation with precipitation were examined for several trees in Japan. A significant (1 σ (standard deviation) and 2 σ) εTree increase is observed after rainfall at 89.8% and 90.5% probability. However, rainfall does not always induce significant εTree increases. Rainfall of more than 5 mm/day can induce 1 σ εTree Tree increase at a 59.6% probability. In order to examine whether the increase in εTree affects the L-band σ0 variation in a forest, the four-year temporal variation of the L-band backscattering coefficient (σ0) was estimated from observations by the Advanced Land Observing Satellite Phased Array type L-band Synthetic Aperture Radar. Observed maximum absolute deviations from the mean over the forest area were 1.0 and 1.2 dB for σHH0 and σHV0, respectively, and 4.0 and 3.0 dB over open land. σ0 and rainfall correlations show that εTree and σForest0 are proportional to precipitation integrated over seven or eight days; εSoil and σOpen land0 are proportional to precipitation integrated over three days. This finding indicates that εTree variations influence σForest areas0. A stronger correlation between σHV0 and precipitation is observed in several sites with low σHV0, where less biomass is expected, and several sites with high σHV0, where more biomass is expected. A weaker correlation between σHV0 and precipitation is observed for several sites with high σ- sub>HV0. These differences may be explained by the different contributions of double bounce scattering and potential transpiration, which is a measure of the ability of the atmosphere to remove water from the surface through the processes of transpiration. The two other results were as follows: 1) The functional relation between aboveground biomass and σ0 showed dependence on precipitation data, this being an effect connected with seasonal changes of the εTree. This experiment reinforces the fact that the dry season is preferable for retrieval of woody biomass from inversion of the functional dependence of SAR backscatter and for avoiding the influence of rainfall. 2) The complex dielectric constant for a tree trunk, which is measured between 0.2 and 6 GHz, indicates that free water is dominant in the measured tree. Numéro de notice : A2015-774 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2415832 date de publication en ligne : 05/06/2015 En ligne : https://doi.org/10.1109/TGRS.2015.2415832 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78832
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 11 (November 2015) . - pp 5799 - 5813[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015111 SL Revue Centre de documentation Revues en salle Disponible Image-domain estimation of wall parameters for autofocusing of through-the-wall SAR imagery / Tian Jin in IEEE Transactions on geoscience and remote sensing, vol 51 n° 3 Tome 2 (March 2013)
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Titre : Image-domain estimation of wall parameters for autofocusing of through-the-wall SAR imagery Type de document : Article/Communication Auteurs : Tian Jin, Auteur ; Bo Chen, Auteur ; Zhimin Zhou, Auteur Année de publication : 2013 Article en page(s) : pp 1836 - 1843 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes descripteurs IGN] constante diélectrique
[Termes descripteurs IGN] détection à travers-le-mur
[Termes descripteurs IGN] écho radar
[Termes descripteurs IGN] épaisseur
[Termes descripteurs IGN] image radar moirée
[Termes descripteurs IGN] milieu urbainRésumé : (Auteur) Estimation of the basic parameters, wall thickness and dielectric constant, is important in through-the-wall radar imaging. Ambiguities in wall characteristics will degrade the image focusing quality of synthetic-aperture radar. In order to obtain a quick and precise estimation of wall parameters, an equivalent propagation model of an electromagnetic wave in the air-wall-air medium is first developed in this paper. According to the developed propagation model, two filter-based approaches, denoted respectively as the echo-domain-filter-based method and the image-domain-filter-based method, are proposed to estimate wall thickness and dielectric constant by adjusting the two corresponding parameters of the echo-domain filter or the image-domain filter to obtain the best focusing quality of behind-the-wall targets. The processing schemes of the two methods show that the image-domain-filter-based method is more efficient because it does not involve imaging processing in each adjustment. Moreover, the image-domain-filter-based method is accelerated by reducing the dimension of searching space to better the computational efficiency further. Simulation results show that the proposed accelerating image-domain-filter-based method can provide quick and precise estimation of wall parameters. Numéro de notice : A2013-136 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2206395 En ligne : https://doi.org/10.1109/TGRS.2012.2206395 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32274
in IEEE Transactions on geoscience and remote sensing > vol 51 n° 3 Tome 2 (March 2013) . - pp 1836 - 1843[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2013031B RAB Revue Centre de documentation En réserve 3L Disponible Physical limitations on detecting tunnels using underground-focusing spotlight synthetic aperture radar / J. Martinez-Lorenzo in IEEE Transactions on geoscience and remote sensing, vol 49 n° 1 Tome 1 (January 2011)
PermalinkSnow permitivity retrieval inversion algorithm for estimating snow wetness / G. Singh in Geocarto international, vol 25 n° 3 (June 2010)
PermalinkUtilizing calibrated GPS reflected signals to estimate soil reflectivity and dielectric constant: results from SMEX02 / S.J. Katzberg in Remote sensing of environment, vol 100 n° 1 (15/01/2006)
PermalinkBackscatter and dielectric measurements from rocks of south-eastern Utah at C-band, X-band and KU-band / R. Swanson in International Journal of Remote Sensing IJRS, vol 9 n° 4 (April 1988)
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