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3-Pol polarimetric weather measurements with agile-beam phased-array radars / Verónica Santalla del Rio in IEEE Transactions on geoscience and remote sensing, vol 52 n° 9 Tome 2 (September 2014)
[article]
Titre : 3-Pol polarimetric weather measurements with agile-beam phased-array radars Type de document : Article/Communication Auteurs : Verónica Santalla del Rio, Auteur ; José Manuel Pidre Mosquera, Auteur ; Mariá Vera-Isasa, Auteur Année de publication : 2014 Article en page(s) : pp 5783 - 5789 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] données météorologiques
[Termes IGN] écho radar
[Termes IGN] phase
[Termes IGN] polarimétrie radarRésumé : (Auteur) Most actual polarimetric weather radars consider either alternate transmission of horizontal and vertical polarizations or simultaneous transmission of both polarizations. Simultaneous reception of vertical and horizontal components is always performed. The way these operating modes have to be modified, to cope with the loss of polarization purity and the increase of polarization channels coupling at some pointing directions when planar phased-array radars (PARs) are used, has already been discussed. Complete correction of these effects showed to be difficult, requiring precise control of the relative amplitudes and phases of the dipoles feeding signals on transmission in a pulse-to-pulse basis. If simultaneous transmission of vertical and horizontal polarizations is considered, complete correction has not been achieved. In this paper, the implementation of a third polarimetric measurement mode based on alternate transmission of three different polarizations with PARs is discussed. It is found that implementation of this method, which provides minimum-variance unbiased linear polarimetric covariance matrix estimates, with phased-array systems only requires simple adjustments at reception. Numéro de notice : A2014-445 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2013.2292639 En ligne : https://ieeexplore.ieee.org/document/6684564 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74172
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 9 Tome 2 (September 2014) . - pp 5783 - 5789[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2014091B RAB Revue Centre de documentation En réserve L003 Disponible An accurate and computationally efficient algorithm for ground peak identification in large footprint waveform LiDAR data / Wei Zhuang in ISPRS Journal of photogrammetry and remote sensing, vol 95 (September 2014)
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Titre : An accurate and computationally efficient algorithm for ground peak identification in large footprint waveform LiDAR data Type de document : Article/Communication Auteurs : Wei Zhuang, Auteur ; Giorgos Mountrakis, Auteur Année de publication : 2014 Article en page(s) : pp 81 – 92 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] empreinte
[Termes IGN] filtrage numérique d'image
[Termes IGN] forêt
[Termes IGN] forme d'onde
[Termes IGN] groupe
[Termes IGN] identification automatique
[Termes IGN] onde lidar
[Termes IGN] surface du sol
[Termes IGN] télémétrie laser aéroporté
[Termes IGN] traitement de donnéesRésumé : (Auteur) Large footprint waveform LiDAR sensors have been widely used for numerous airborne studies. Ground peak identification in a large footprint waveform is a significant bottleneck in exploring full usage of the waveform datasets. In the current study, an accurate and computationally efficient algorithm was developed for ground peak identification, called Filtering and Clustering Algorithm (FICA). The method was evaluated on Land, Vegetation, and Ice Sensor (LVIS) waveform datasets acquired over Central NY. FICA incorporates a set of multi-scale second derivative filters and a k-means clustering algorithm in order to avoid detecting false ground peaks. FICA was tested in five different land cover types (deciduous trees, coniferous trees, shrub, grass and developed area) and showed more accurate results when compared to existing algorithms. More specifically, compared with Gaussian decomposition, the RMSE ground peak identification by FICA was 2.82 m (5.29 m for GD) in deciduous plots, 3.25 m (4.57 m for GD) in coniferous plots, 2.63 m (2.83 m for GD) in shrub plots, 0.82 m (0.93 m for GD) in grass plots, and 0.70 m (0.51 m for GD) in plots of developed areas. FICA performance was also relatively consistent under various slope and canopy coverage (CC) conditions. In addition, FICA showed better computational efficiency compared to existing methods. FICA’s major computational and accuracy advantage is a result of the adopted multi-scale signal processing procedures that concentrate on local portions of the signal as opposed to the Gaussian decomposition that uses a curve-fitting strategy applied in the entire signal. The FICA algorithm is a good candidate for large-scale implementation on future space-borne waveform LiDAR sensors. Numéro de notice : A2014-474 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2014.06.004 En ligne : https://doi.org/10.1016/j.isprsjprs.2014.06.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74051
in ISPRS Journal of photogrammetry and remote sensing > vol 95 (September 2014) . - pp 81 – 92[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2014091 RAB Revue Centre de documentation En réserve L003 Disponible An enhanced strategy for GNSS data processing of massive networks / H. Chen in Journal of geodesy, vol 88 n° 9 (September 2014)
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Titre : An enhanced strategy for GNSS data processing of massive networks Type de document : Article/Communication Auteurs : H. Chen, Auteur ; W. Jiang, Auteur ; Maorong Ge, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 857-867 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] longueur d'onde
[Termes IGN] phase GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïtéRésumé : (Auteur)Although the computational burden of global navigation satellite systems (GNSS) data processing is nowadays already a big challenge, especially for huge networks, integrated processing of denser networks with data of multi-GNSS and multi-frequency is desired in the expectation of more accurate and reliable products. Based on the concept of carrier range, in this study, the precise point positioning with integer ambiguity resolution is engaged to obtain the integer ambiguities for converting carrier phases to carrier ranges. With such carrier ranges and pseudo-ranges, rigorous integrated processing is realized computational efficiently for the orbit and clock estimation using massive networks. The strategy is validated in terms of computational efficiency and product quality using data of the IGS network with about 460 stations. The experimental validation shows that the computation time of the new strategy increases gradually with the number of stations. It takes about 14 min for precise orbit and clock determination with 460 stations, while the current strategy needs about 82 min. The overlapping orbit RMS is reduced from 27.6 mm with 100 stations to 24.8 mm using the proposed strategy, and the RMS could be further reduced to 23.2 mm by including all 460 stations. Therefore, the new strategy could be applied to massive networks of multi-GNSS and multi-frequency receivers and possibly to achieve GNSS data products of higher quality. Numéro de notice : A2013-546 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0727-7 Date de publication en ligne : 05/06/2014 En ligne : https://doi.org/10.1007/s00190-014-0727-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74028
in Journal of geodesy > vol 88 n° 9 (September 2014) . - pp 857-867[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2014091 SL Revue Centre de documentation Revues en salle Disponible UAV shipboard landing with RTK: a carrier phase compensates for wind and wave motion / Chiu-Jung Huang in GPS world, vol 25 n° 5 (May 2014)
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Titre : UAV shipboard landing with RTK: a carrier phase compensates for wind and wave motion Type de document : Article/Communication Auteurs : Chiu-Jung Huang, Auteur ; Shau-Shiun Jan, Auteur Année de publication : 2014 Article en page(s) : pp 34 - 42 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] compensation
[Termes IGN] drone
[Termes IGN] onde porteuse
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] précision du positionnementRésumé : (Auteur) Limited landing area as well as interference due to wind disturbance and wave motion make landings of unmanned aerial vehicles (UAVs) extremely difficult. Use of UAVs at sea enhance the efficiency of intelligence gathering and surveillance, and could also increase long-range air-strike capability. To successfully land aircraft in such a challenging environment requires a high-precision navigation system; this prototype applies RTK measurements. Numéro de notice : A2014-204 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33107
in GPS world > vol 25 n° 5 (May 2014) . - pp 34 - 42[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 067-2014051 RAB Revue Centre de documentation En réserve L003 Disponible Full-wave calibration of time- and frequency-domain ground-penetrating radar in far-field conditions / Mohammad Reza Mahmoudzadeh Ardekani in IEEE Transactions on geoscience and remote sensing, vol 52 n° 1 tome 2 (January 2014)
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Titre : Full-wave calibration of time- and frequency-domain ground-penetrating radar in far-field conditions Type de document : Article/Communication Auteurs : Mohammad Reza Mahmoudzadeh Ardekani, Auteur ; Sébastien Lambot, Auteur Année de publication : 2014 Article en page(s) : pp 664 - 678 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] étalonnage d'instrument
[Termes IGN] forme d'onde pleine
[Termes IGN] fréquence
[Termes IGN] image radar
[Termes IGN] radar pénétrant GPR
[Termes IGN] tempsRésumé : (Auteur) Full-wave modeling of ground-penetrating radar (GPR) data using Green's functions for wave propagation in planar layered media and antenna characteristic global reflection and transmission functions for describing far-field antenna effects, including antenna-medium interactions, has shown a great potential for nondestructive characterization of soils and materials. The accuracy of the retrieved parameters in the GPR data inversion depends on the accuracy of the GPR external calibration. In this research, we studied the stability and the repeatability of two different GPR systems, namely, frequency- and time-domain systems. A combination of a vector network analyzer and 800-5200 MHz horn antenna was used as a frequency-domain GPR (FD-GPR) whereas a GSSI GPR system using a 900 MHz bowtie antenna was used as a time-domain GPR (TD-GPR). Both GPR systems including their antennas were calibrated several times using measurements with the antennas at different heights over a perfect electric conductor (PEC) in the laboratory as well as over a water layer. In addition, measurements were performed over a thin water layer and a relatively thick sandy soil layer as validating medium. The results showed that the FD-GPR is relatively stable while the TD-GPR presents a significant drift which can be accounted for using corrections based on the air direct-coupling waves (free-space measurements). Water- and PEC-based calibrations provided very similar results for the GPR calibration functions. Inversions for the water layer and the sandy soil layer provided reliable results and showed a high degree of the repeatability for both radar systems. The error on the calibration based on inaccurate antenna heights over PEC showed the significant errors on the inversion results for the directive antenna (horn antenna) but less error for the bowtie antenna. This analysis demonstrated the general validity of the proposed far-field radar modeling approach, not only with respect to frequency and time domain radars but as well with respect to the calibrating medium. Numéro de notice : A2014-039 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2013.2243458 En ligne : https://doi.org/10.1109/TGRS.2013.2243458 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32944
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 1 tome 2 (January 2014) . - pp 664 - 678[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2014011B RAB Revue Centre de documentation En réserve L003 Disponible Permalink3D tree reconstruction from simulated small footprint waveform lidar / Jiaying Wu in Photogrammetric Engineering & Remote Sensing, PERS, vol 79 n° 12 (December 2013)PermalinkIntegrated denoising and unwrapping of INSAR phase based on Markov random fields / Runpu Chen in IEEE Transactions on geoscience and remote sensing, vol 51 n° 8 (August 2013)PermalinkGenerating distorded GNSS signals using a signal simulator / Mathieu Raimondi in GPS world, vol 24 n° 5 (May 2013)PermalinkStem volume and above-ground biomass estimation of individual pine trees from LiDAR data: contribution of full-waveform signals / Tristan Allouis in IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, vol 6 n° 2 part 3 (April 2013)PermalinkDirectionally adaptive filter for synthetic aperture radar interferometric phase images / S. Fu in IEEE Transactions on geoscience and remote sensing, vol 51 n° 1 Tome 2 (January 2013)PermalinkPermalinkGalileo IOV-3 broadcasts E1, E5, E6 signals / Oliver Montenbruck in GPS world, vol 24 n° 1 (January 2013)PermalinkImprovement of stepped-frequency continuous wave Ground-Penetrating Radar cross-range resolution / I. Nicolaescu in IEEE Transactions on geoscience and remote sensing, vol 51 n° 1 Tome 1 (January 2013)PermalinkJoint estimation of moving target reflectivity and velocity via AT-InSAR systems based on complex interferometric data / Alessandra Budillon in ISPRS Journal of photogrammetry and remote sensing, vol 75 (January 2013)Permalink