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162 results on '"Guiffaut, Christophe"'

7. Angle-dependent SIBC model of metamaterial in FDTD method

Author

Gaucher, Samuel, Guiffaut, Christophe, Reineix, Alain, Cessenat, Olivier, Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), and CEA-CESTA (Le Barp, Gironde)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, FDTD, Palaiseau, France SIBC, metamaterial, WAVES 2022
Abstract

International audience; To control the diffraction of a target illuminated by a RADAR wave, one technique is to consider metamaterials. Simulating their behaviour can be complex especially when they are applied as thin heterogeneous layers on the surface of the target. This can be achieved, by first determining an angle-dependent surface impedance model, that is after implemented in a 3D FDTD solver.

Published
2022

8. Angle-dependent SIBC model of metamaterial in conformal FDTD method

Author

Gaucher, Samuel, Guiffaut, Christophe, Reineix, Alain, Cessenat, Olivier, Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), CEA-CESTA (Le Barp, Gironde), and Reineix, Alain

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [SPI.ELEC] Engineering Sciences [physics]/Electromagnetism, SIBC, metamaterial, conformal FDTD
Abstract

International audience; To control the diffraction of a target illuminated by a radar wave, one technique is to consider metamaterials. Simulating their behaviour can be complex especially when they are applied as thin heterogeneous layers on the surface of the target. This can be achieved, by first determining an angledependent surface impedance model, that is after implemented in a 3D conformal FDTD solver.

Published
2022

11. Alternative quantum circuit implementation for 2D electromagnetic wave simulation with quasi-PEC modeling

Author

Bui, Nicolas, Reineix, Alain, Guiffaut, Christophe, and Reineix, Alain

Subjects
[SPI.ELEC] Engineering Sciences [physics]/Electromagnetism, Maxwell solver, Quantum Computing, PEC modeling
Abstract

Numerical simulation may benefits from quantum computing (QC) potential to solve particular problems faster than its classical counterpart. This motivates recent works [1, 2, 3] to solve the wave equation with a quantum computer. Here, we consider 2D wave propagation in free space based on an alternative implementation of the quantum algorithm developed in [2, 3]. We also propose a way to model quasi perfect electrical conductor (PEC). An example of a plane wave reflection is given, with QC on a simulator.

Published
2022

12. Modèle SIBC pour la simulation FDTD d'une cible recouverte de métamatériaux

Author

Gaucher, S, Reineix, Alain, Guiffaut, Christophe, Cessenat, O, Reineix, Alain, Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), and CEA-CESTA (Le Barp, Gironde)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [SPI.ELEC] Engineering Sciences [physics]/Electromagnetism
Abstract

International audience; Pour contrôler la diffraction d'une cible éclairée par une onde radar, une technique est d'utiliser des métamatériaux avec des propriétés d'absorption ou de redirection du champ. Leur prise en compte dans les outils de simulation peut s'avérer complexe surtout lorsqu'ils sont appliqués sous forme de couches minces hétérogènes à la surface de la cible. Ceci peut être réalisé en déterminant d'abord un modèle d'impédance de surface dépendant de l'angle d'incidence, qui est ensuite implémenté dans un solveur 3D FDTD.

Published
2022

14. Analyse Théorique d'un Grand Système Antennaire Soumis à une agression Électromagnétique Transitoire

Author

Maurice, Olivier, Leman, Samuel, Rabaste, J, Laisne, A, Pouliguen, Philippe, Guiffaut, Christophe, Reineix, Alain, ArianeGroup, Société NEXIO, Délégation générale de l'armement (DGA), Ministère de la Défense, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism
Abstract

International audience; La compatibilité électromagnétique évolue au même rythme que l'électronique. La grande difficulté dans une démarche de conception système réside dans l'aspect multiéchelle des problèmes, intégrant des interactions au niveau de larges structures et des défaillances au niveau des composants électroniques. Les calculs de risques et de marges qui s'en déduisent sont difficiles, nécessitant des estimations à ces deux niveaux.

Published
2021

15. Méhode de caracterisation large bande de materiaux dielectriques liquides et multi-couches

Author

Monferran, P, Marie-Joseph, Yann, Guiffaut, Christophe, Reineix, Alain, Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), and Reineix, Alain

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [SPI.ELEC] Engineering Sciences [physics]/Electromagnetism
Abstract

International audience; Cet article propose d'étendre les performances d'une méthode de caractérisation de matériaux diélectriques et ferrites aux matériaux liquides et multi-couches. Après avoir rappelé les principes de cette méthode de caractérisation qui s'appuie sur la mesure des paramètres S d'une cellule quasi-TEM avec et sans échantillon et un algorithme d'optimisation visant à minimiser la différence entre les paramètres S mesurés et ceux calculés en simulation 3D, différentes approches de caractérisation du liquide et du récipient sont proposées. La sensibilité de la méthode à la précision de la modélisation de la structure propagatrice et aux différentes approches de caractérisation est étudiée. Les résultats mettent en exergue les performances remarquables de la caractérisation quelles que soient les modélisations et les approches utilisées.

Published
2021

18. Amélioration des modèles pour le calcul des fonctions de transfert HIRF

Author

Bastard, Camille, Meyer, Marc, Guiffaut, Christophe, Reineix, Alain, Reineix, Alain, Airbus Helicopters, Aeroport International de Marseille-Provence, XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [SPI.ELEC] Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2021

20. Fastener modeling for lightning current assessment in aircraft fuel tank

Author

Monferran, Paul, Guiffaut, Christophe, Reineix, Alain, Fustin, Fabian, Tristant, F., Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Dassault Aviation, and Guiffaut, Christophe

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [SPI.ELEC] Engineering Sciences [physics]/Electromagnetism
Abstract

International audience; A large number of fasteners are used in an aircraft assembly, because the nonconducting protective paint makes them the only way to drive the current. The lightning current assessment in these fasteners is a challenge carried out by aircraft manufacturers for the lightning certification, butthey generally emphasize on modeling rather than tests which are expensive and time consuming. Despite this, few fastener models [1]-[4] have been proposed, and the uncertainties of their main parameter, a resistive parameter which represents contact resistances, result in inaccuracy of the models. In this paper, we propose to represent a fastener by a lumped resistance into a short wire, and apply the uncertainty model proposed in [5] : each lumped resistance has a stochastic value drawn from a probability distribution. We model a FDTD fuel tank using this fastener model, and perform measurements at various locations of the fuel tank during a lightning strike, with its current directly injected in a fastener. Our goal is to obtain confidence intervals of the current value using FDTD simulations. In order to achieve this, we perform several simulations with differentresistance values drawn from the uncertainty model. We observe that the modeling of the lightning attachment fastener requires specific attention, particularly regarding the current assessment close to this lightning injection point, so we analyze the sensitivity of several models and discuss them. In the case of the fuel tank, we question the use of extended copper foils as protection and show that the measured currents are well within the expectations of our approach,proving its reliability for the lightning currentassessment.

Published
2019

21. An imaging HF GPR using stationary antennas: experimental validation over the Antarctic ice sheet

Author

Le Gall, Alice, Ciarletti, Valerie, Berthelier, Jean-Jacques, Reineix, Alain, Guiffaut, Christophe, Ney, Richard, Dolon, Francois, and Bonaime, Sebastien

Subjects
Ground penetrating radar -- Observations, Sea ice -- Analysis, Sea ice -- Observations, Mars (Planet) -- Observations, Business, Earth sciences, Electronics and electrical industries
Abstract

Terrestrial And Planetary Imaging Radar (TAPIR) is an innovative high-frequency ground-penetrating radar (GPR) developed in the frame of the Martian NetLander mission to probe the subsurface down to kilometric depths. Unlike most GPRs, TAPIR is able to image underground reflectors with stationary antennas. In this paper, after a brief presentation of the instrument, we describe the method developed to interpret data collected during the RAdar of NEtlander in Terre Adelie (RANETA) field survey in Antarctica. This method consists of retrieving the direction of arrival of each detected echo through the measurement of five components of the electromagnetic field (the three magnetic components and the horizontal components of the electric field). Thus, both the range and the direction of each individual reflection or diffraction due to the ice-bedrock interface are resolved. We validated this method on finite-difference time-domain numerically simulated data for different subsurface configurations before applying it to RANETA observations. In particular, the irregular topography of the bedrock in two sounding sites was revealed. We discuss the accuracy of our results. Index Terms--Deep soundings, finite-difference time domain (FDTD), ground-penetrating radar (GPR), ice, Mars, subsurface, wave propagation.

Published
2008

26. Ways of Improvment of HIRF Transfer Function Assessment on Rotorcraft

Author

Bastard, Camille, Meyer, Marc, Guiffaut, Christophe, Reineix, Alain, Reineix, Alain, Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Airbus Helicopters, and Aeroport International de Marseille-Provence

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [SPI.ELEC] Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

27. Etude statistique sur les résistances de contact des fixations d'avion et analyse de lignes d'assemblage sur caisson

Author

Monferran, Paul, Guiffaut, Christophe, Reineix, Alain, Fustin, Fabian, Tristant, Fabrice, Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), and Dassault Aviation

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

28. Evaluation de l'implantation et du découplage d'antennes large bande sur porteur par des modèles équivalents implantés dans une méthode FDTD

Author

Romeuf, Xavier, Strub, Thomas, Girard, Christophe, Chanel, Clément, Guena, Arnaud, Ticaud, Nicolas, Guiffaut, Christophe, Reineix, Alain, AxesSim, THALES COMMUNICATIONS & SECURITY, THALES, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

29. Répartition de l'énergie dans une structure multicavités

Author

Reineix, Alain, Guiffaut, Christophe, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

30. Détection de défauts non francs le long d'un câble coaxial par des méthodes probabilistes

Author

Bzikha, Ihssane, Velayudhan, Vipin, Guiffaut, Christophe, Reineix, Alain, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

32. Subsurface characterization by the ground penetrating radar WISDOM/ExoMars 2020

Author

Herve, Yann, Ciarletti, Valérie, Le Gall, Alice, Oudart, Nicolas, Loizeau, Damien, Guiffaut, Christophe, Dorizon, Sophie, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), OSA (XLIM-OSA), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Cardon, Catherine

Subjects
[SDU] Sciences of the Universe [physics], [SDU.ASTR.IM] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [SDU]Sciences of the Universe [physics], [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract

International audience; The main objective of the ExoMars 2020 mission is to search for signs of past and/or present life on Mars. Toward this goal, a rover was designed to investigate the shallow subsurface which is the most likely place where signs of life may be preserved, beneath the hostile surface of Mars. The rover of the ExoMars 2020 mission has on board a polarimetric ground penetrating radar called WISDOM (Water Ice Subsurface Deposits Observation on Mars). Thanks to its large frequency bandwidth of 2.5 GHz, WISDOM is able to probe down to a depth of approximately 3 m on sedimentary rock with a vertical resolution of a few centimeters.The main scientific objectives of WISDOM are to characterize the shallow subsurface of Mars, to help understand the local geological context and to identify the most promising location for drilling.The WISDOM team is currently working on the preparation of the scientific return of the ExoMars 2020 mission. In particular, tools are developed to interpret WISDOM experimental data and, more specifically, to extract information from the radar signatures of expected buried reflectors.Insights into the composition of the ground (through the retrieval of its permittivity) and the geological context of the site can be inferred from the radar signature of buried rocks since the shape and the density of rocks in the subsurface is related to the geological processes that have shaped and placed them there (impact, fluvial processes, volcanism).This paper presents results obtained by automatic detection of structures of interest on a radargram, especially radar signature of buried rocks. The algorithm we developed uses a neural network to identify the position of buried rocks/blocs and then a Hough transform to characterize each signature and to estimate the local permittivity of the medium. Firstly, we will test the performances of the algorithm on simulated data constructed with a 3D FDTD code. This code allows us to simulate radar operation in realistic environments. Secondly, we will test our algorithm on experimental data acquired in a semi-controlled environment. Lastly, we will present experimental data acquired during a recent field campaign (July 2017) in the south of France and we will validate our method and illustrate the ability of WISDOM to provide clues about the geological context of a site.

Published
2017

33. Wideband Characterization of Ni-Zn ferrite tile in a TEM structure

Author

Monferran, Paul, Tumayan, Rémi, Guiffaut, Christophe, Andrieu, Guillaume, Reineix, Alain, Bunlon, X., Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Technocentre Renault [Guyancourt], and RENAULT

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

34. Electromagnetic Field Radiated by Lightning High Voltage Battery fro Electric Vehiicle

Author

Tumayan, Rémi, Bunlon, X., Reineix, Alain, Andrieu, Guillaume, Guiffaut, Christophe, Technocentre Renault [Guyancourt], RENAULT, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

35. 3D mapping of buried rocks by the GPR WISDOM/ExoMars 2020

Author

Herve, Yann, Ciarletti, Valérie, Le Gall, Alice, Quantin, Cathy, Guiffaut, Christophe, Plettemeier, Dirk, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), and Cardon, Catherine

Subjects
[SDU] Sciences of the Universe [physics], [SDU]Sciences of the Universe [physics]
Abstract

International audience; The main objective of ExoMars 2020 is to search for signs of past and/or present life on Mars. Because these signs may be beneath the inhospitable surface of Mars, the ExoMars Rover has on board a suite of instruments aiming at characterizing the subsurface. In particular, the Rover payload includes WISDOM (Water Ice Subsurface Deposits Observation on Mars), a polarimetric ground penetrating radar designed to investigate the shallow subsurface. WISDOM is able to probe down to a depth of few meters with a resolution of few centimeters; its main objective is to provide insights into the geological context of the investigated Martian sites and to determine the most promising location to collect samples for the ExoMars drill. In this paper, we demonstrate the ability of WISDOM to locate buried rocks and to estimate their size distribution. Indeed, the rock distribution is related to the geological processes at play in the past or currently and thus provides clues to understand the geological context of the investigated site. Rocks also represent a hazard for drilling operations that WISDOM is to guide. We use a 3D FDTD code called TEMSI-FD (which takes into account the radiation pattern of the antenna system) to simulate WISDOM operations on a realistic (both in terms of dielectric properties and structure) ground. More specifically, our geoelectrical models of the Martian subsurface take into account realistic values of the complex permittivity relying on published measurements performed in laboratory on Martian analogues. Further, different distributions of buried rocks are considered based on the size-frequency distribution observed at the Mars Pathfinder landing site and on Oxia Planum, the landing site currently selected for ExoMars 2020. We will describe the algorithm we developed to automatically detect the signature of the buried rocks on radargrams. The radargrams are obtained simulating WISDOM operations along parallel and perpendicular profiles as planned for the ExoMars mission. Our ultimate goal is to show that WISDOM observations can be used to build a 3D map of the subsurface. We will also present experimental data obtained with a prototype of WISDOM to test our method.

Published
2017

36. Characterizing the interior of 67P in the vicinity of Abydos

Author

Ciarletti, Valérie, Lasue, Jérémie, Lemonnier, Florentin, Herique, Alain, Kofman, Wlodek W., Guiffaut, Christophe, Levasseur-Regourd, Anny Chantal, Plettemeier, Dirk, IMPEC - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), ESTER - LATMOS, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Technische Universität Dresden (TUD), PLANETO - LATMOS, Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; Since the arrival of Rosetta at comet 67P, numerous pictures have been delivered by the cameras onboard both the main spacecraft and the Philae lander. They revealed, at the nucleus' surface and inside the walls of the deep pits, few-meters scale repeating structures, thus providing hints about the internal structure of the nucleus, and suggesting that primordial 'cometesimals' may be objects around 3m in size.The CONSERT (Comet Nucleus Sounding Experiment by Radiowave Transmission) experiment is a radar that has been designed to specifically sound the interior of the nucleus and to provide information on the nucleus internal structure. The work presented here is based on the CONSERT data collected during the First Science Sequence (FSS) and marginally during Philae’s Separation Descent and Landing (SDL) for comparison.During FFS, the smaller lobe of the nucleus in the vicinity of Abydos has been actually sounded by CONSERT’s electromagnetic waves at 90 MHz with a spatial resolution around 10 m. The propagation delays measured during FSS are consistent with a very low bulk permittivity value for the investigated cometary material, which confirms the high porosity of the nucleus. The sharp shape of the received pulses indicates that the electromagnetic waves suffered weak scattering when propagating through the nucleus. This suggests that the sounded part nucleus is thus fairly homogeneous on a spatial scale of tens of meters.We will present further results on the variation of the CONSERT’s pulse shape transmitted through the small lobe of the nucleus. For a more accurate analysis and interpretation of the data, we split the FSS data into two distinct sets corresponding to soundings performed West and East of Philae in order to investigate potential differences. Tentative interpretation in terms of nucleus internal structure based on propagation simulations performed in non-homogeneous nucleus numerical models will be presented.

Published
2016

40. Modèle équivalent large bande d'antennes pour implémentation sur porteur

Author

Guiffaut, Christophe, Ticaud, Nicolas, Reineix, Alain, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

41. Évaluation du champ électrique rayonné par un pack batterie allégé pour véhicule automobile

Author

Tumayan, Rémi, Bunlon, X., Reineix, Alain, Andrieu, Guillaume, Guiffaut, Christophe, Technocentre Renault [Guyancourt], RENAULT, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

42. Assessment of the potential rise of a thin wire in the FDTD modelled with the formalism of Holland

Author

Diaz, Luis, Miry, Celine, Reineix, Alain, Baraton, Philippe, Guiffaut, Christophe, Systèmes RF (XLIM-SRF), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), and EDF (EDF)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

43. Modèle dipolaire de rayonnement d'antennes obtenu à partir de diagrammes de rayonnement en vue d'applications antennes sur porteur

Author

Reineix, Alain, Guiffaut, Christophe, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

44. « Prev | Back to Results | Next »Use of Adaptive Kriging Metamodeling in Reliability Analysis of Radiated Susceptibility in Coaxial Shielded Cables

Author

Bdour, Tarek, Guiffaut, Christophe, Reineix, Alain, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
shielded cable, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, reliability analysis, sensi- tivity analysis (SA), Radiated susceptibility
Abstract

International audience; In this paper, reliability analysis is applied to assess electromagnetic risk due to external electromagnetic waves in a coaxial shielded cable. Generally, the classical sampling method— Monte Carlo (MC)—is used to conduct thousands or millions of runs of the numerical model. As this latter is time-demanding, the computational cost becomes prohibitive. As an alternative, an advanced metamodeling method based on Kriging is proposed for efficiently assessing small failure probabilities. This method is called AK-MCS. It consists in an active learning reliability method combining Kriging and MC simulation. Metamodeling reduces the computational run time by replacing the true numerical model by an inexpensive surrogate model. The interpolated surrogate model presents the advantage to be rapidly handled by MC simulations to calculate the failure probability. AK-MCS method is based on an adaptive strategy to enrich the design of experiments (DOE) with significant sampling points near the failure region, and hence, Kriging model is ameliorated and so is the assessment of failure probability. Three numerical examples of radiated susceptibility in a shielded cable are conducted to demonstrate the efficiency of the underlined Kriging approach. Reliable metamodels can be obtained through a small number of runs of the true numerical model, and it is found that the computed failure probabilities are very accurate compared to crude MC simulation results.

Published
2016

45. Characterization of rocks buried in the subsurface by the GPR WISDOM/ExoMars 2020

Author

Herve, Yann, Ciarletti, Valérie, Le Gall, Alice, Guiffaut, Christophe, Cardon, Catherine, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ESTER - LATMOS, Systèmes RF (XLIM-SRF), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; The search for evidence of past life on Mars is the main objective of the ESA-Roscosmos ExoMars Rover mission. Given the hostile environment at the surface, if such evidence is to be found anywhere, it will most likely be in the subsurface. This is why the ExoMars rover mission has been optimized to investigate the subsurface. Among the instruments accommodated onboard the Rover, the polarimetric ground penetrating radar WISDOM (Water Ice Subsurface Deposits Observation On Mars, Ciarletti et al., 2011) has been designed to investigate the shallow subsurface and search for the most favorable locations where to drill and collect samples for analysis. WISDOM is able to probe down to a depth of few meters with a vertical resolution of a few centimeters, and will provide key information on the geological context of the environment.In particular, insights into density, size and shape of the rocks buried beneath the rover would be clues for a better understanding of the geological and hydrological history of the Rover site. In addition, the density and size of the buried rocks will have to be taken into account for the safety of the drilling operations.In this paper, we will focus on the ability of WISDOM to detect, localize and characterize (in terms of size and shape), rocks in the shallow subsurface of Mars. More specifically, we use a 3D numerical code based on the Finite Difference in Time Domain method to model the antenna system of WISDOM and simulate the instrument operations on realistic environments with buried rocks. In this approach, size-frequency distribution of rocks in agreement with observations from orbit and by cameras operated from the Martian surface will be considered. We will present results of simulations for different density and shape of buried rocks, including critical configurations where the density of rocks is too high to allow individual detection of rocks. In addition, we will present experimental data for comparison with the simulated data.References:V. Ciarletti, C. Corbel, D. Plettemeier, P. Caïs, S. M. Clifford, and S. E. Hamran, "WISDOM GPR Designed for Shallow and High-Resolution Sounding of the Martian Subsurface " Proceedings of the IEEE, vol. 99, no. 99, pp. 1-13, 2011.

Published
2016

48. Calculation of Lightning transient voltages in cables considering a large industrial site using a FDTD thin wire model

Author

Diaz, Luis, Miry, Céline, Guiffaut, Christophe, Reineix, Alain, OSA (XLIM-OSA), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), and EDF (EDF)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

49. Fuel-Tank Safety- 3D computations for attachment and conduction assessment

Author

Tristant, Fabrice, Fustin, Fabian, Terrade, Fabien, Roussel, M., parfait, F., Largo, F., Berthet, M., Reineix, Alain, Guiffaut, Christophe, Laisne, Alexandre, OSA (XLIM-OSA), XLIM (XLIM), and Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [SPI]Engineering Sciences [physics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

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