Teses / dissertações sobre o tema "Génération par difference de fréquence"
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Bernerd, Cyril. "Génération d'ondes TeraHertz par Différence de Fréquence". Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT061/document.
Texto completo da fonteTHz-waves extend from the far InfraRed (15 μm – 20 THz) to radio waves (3000 μm – 0.1 THz). Current sources based on thermal (Mercury lamps…), electronics (Gunn diode...) or optics (laser, antennas…) technologies can’t cover this wide spectral range for applications in spectroscopy and imaging. An alternative is provided by parametric nonlinear optics, which leads to the generation of THz waves from Difference Frequency Generation (DFG) by injecting one or two lasers in a nonlinear crystal. To better cover the wide THz domain, it is necessary to determine nonlinear crystals with optical properties leading to the generation of such waves with high conversion efficiencies.This PhD thesis is devoted to the study of these properties for a panel of nonlinear crystals, along with experimental results of THz generation from DFG between two monochromatic lasers in the nanosecond and picosecond regimes, or between two Fourier components within a femtosecond laser. We selected twenty new crystals never studied before in the THz domain, along with the organic crystal of BNA. We measured their transmission spectra from visible to THz, and their nonlinear properties including phase-matching conditions and conversion efficiency
Mutin, Pascal. "Génération de fréquences infrarouges par mélange de lasers à colorants pulsés dans des cristaux non linéaires : application à la spectroscopie à haute résolution". Dijon, 1988. http://www.theses.fr/1988DIJOS023.
Texto completo da fonteCui, Xiaojuan. "Research of trace gases detection methods based on mid-infrared modern photonic instruments". Electronic Thesis or Diss., Littoral, 2011. http://www.theses.fr/2011DUNK0519.
Texto completo da fonteThis thesis includes two parts: Development and application of a continuous-wave quantum cascade laser (CW-QCL) based instrument for measurements and study of nitrous acid (HONO) and a broadly tunable mid-infrared laser system based on difference frequency generation (DFG) in periodically poled lithium niobate (PPLN) for trace gas ( HCl, CH2O, HONO) monitoring. The OH radical is one of the key species in photochemical cycles responsible for ozone formation, which can lead to the so-called "photochemical smog" pollution. The hydroxyl radical also drives the oxidation of hydrocarbons in the atmosphere. Gaseous nitrous acid (HONO) is a major source of the OH radical in the early morning and daytime. So HONO directly affects the oxidative capacity of the atmosphere and indirectly contributes to secondary pollutants which are products of that oxidation. High accurate and precise concentration measurement of the atmospheric HONO requires high sensitivity and stability, good temporal and spatial resolution. One part of this thesis has been firstly devoted to the design of an optical instrument based on a continuous-wave (CW) quantum cascade laser (QCL) operating at 8 μm (~1255 cm ֿ ¹) for HONO detection. The sensitivity and specificity of the instrument were evaluated and described using HONO sample generated by chemical reaction of H₂SO₄ and NaNO₂. The generated HONO concentration was quantified by means of a denuder system associated with a conventional NOX analyzer. Moreover, within the limits of the QCL frequency, only 5 absorption line intensities of HONO can be found from the reference, so we measured the relative frequencies and line intensities of the remaining absorption lines especially the one which was used to do trace gas measurement. Line strengths of 19 stronger absorption lines observed are found to be around (3-90)×10-21 cm. Direct absorption spectroscopy technique combined with a 125 m multi-pass cell was applied to develop trace gas detection of HONO. In order to improve the sensitivity, wavelength modulation technique was applied, the minimum detectable HONO concentration resulting in a noise-equivalent signal was found to be about 400 ppt in 1 second integration time and fit for field measurements. HONO losses resulted from the optical cell wall was experimentally investigated. The rate constant of HONO determined in the present work might be helpful for field measurements of HONO, especially the measurements using absorption cell. Finally,the QCL-based instrument developed in the present work has been evaluated with in-door simultaneous measurements of HONO and i i CH4. The concentration of the two species obtained in the laboratory were 116 ppb and 1.5 ppm, and the corresponding 1 σ minimum detectable concentrations (MDC) in 1-second integration time are 396 ppt and 6 ppb for HONO and CH4, respectively. The other part of this thesis is focused on highly sensitive trace gas detection employing a room-temperature, broadly tunable and narrow linewidth mid-infrared difference frequency generation laser source. The mid-infrared laser system is based on quasi-phase-matched (QPM) and DFG with a multi-grating temperature-controlled periodically poled LiNbO3 (PPLN) crystal employing two near-infrared diode lasers as pump sources. The mid-infrared coherent radiation is tunable from 3.2 μm to 3.7 μm. Detection of HCl, CH2O has been carried out. According to the absorption band (3590 cm-1) of HONO from references, another DFG laser sources employing a Ti: Sapphire laser and an Yb fiber laser as pump sources was developed, and the output frequency calibration was carried out using pure CO2 gas. HONO measurement in this wavelength range will be performed in the next work
本论文主要包括两个部分:一是基于室温连续波量子级联激光器光源,设 计并搭建了一套测量HONO 气体的系统,然后用该系统进行了HONO 气体的 探测和研究。二是利用室温操作的宽调谐差频产生中红外激光器系统进行痕量 气体(HCl, CH2O,HONO)的探测。OH 自由基是光化学循环的主要物种之一,并对臭氧的形成有重要影响,从而导致所谓的“光化学烟雾”污染。OH 自由基同时也影响着大气中烃类的氧化 能力。气态亚硝酸是清晨和白天OH 自由基的一个主要来源。因此,亚硝酸直 接影响大气的氧化能力,同时也间接推动了由于氧化过程而产生的二次污染物 的形成。大气中亚硝酸浓度的精确测量需要仪器具备高的灵敏度和稳定性,以 及好的时间和空间分辨率。本论文的主要工作之一就是设计一套以8 μm (~1255 cm-1)连续波量子级联激光器为基础对HONO 气体进行探测的装置。并利用由 H2SO4 和 NaNO2 发生化学反应而产生的HONO 气体估算和描述该装置的灵敏度和特性。产生的HONO 浓度由一个溶蚀器系统和一个NOX 分析仪来量化。在该量子级联激光器频率范围内(1254.6-1256.4 cm-1) ,只能从文献中查阅到 HONO 的5 条吸收线线强,因此测量了HONO 用于进行痕量探测的吸收线以及 其他吸收线的相对频率和线强,得到的十九条较强吸收线的线强范围大约在 (3-90)×10-21 cm。用直接吸收光谱技术结合125 m 的多次反射池对HONO 进行 了痕量探测。为了提高灵敏度,开展了波长调制技术的实验研究,得到HONO 的最低探测浓度(SNR=1) 在1 s 的积分时间内为400 ppt,适合进行外场测量。研究了由光学池壁表面而导致的HONO 的衰减效应并得到一个反应率常数,这个常数可能有助于以后HONO 的场测量,特别是用吸收池的测量。测量了实验 室空气中的HONO 和CH4,得到它们的室内浓度分别为116 ppb 和1.5 ppm, 相应的1 s 积分时间内1 σ 最小可以探测的浓度分别为396 ppt 和6 ppb。论文的另一部分工作是利用一个室温操作的,宽调谐窄线宽中红外差频产 生光源进行痕量气体的探测。该中红外差频产生系统是以准相位匹配为基础,利用两台近红外半导体激光器作为泵浦源,在PPLN 晶体中进行差频,得到的 相关中红外差频输出范围为3.2 μm 到 3.7 μm。用该系统进行了HCl 和 CH2O 气体探测,说明了该装置在工业和环境监测领域有一定的应用潜力。根据文献 得到的HONO 的另一个吸收带3590 cm-1,设计了另一套以钛宝石激光器和掺 Yb 光纤激光器作为泵浦源的差频光源系统,用CO2 气体进行了差频输出光频率 校准, 下一步的工作是进行HONO 气体测量实验。
Tessier, G. "Étude d'interfaces magnétiques par doublage de fréquence optique". Phd thesis, Université Paris Sud - Paris XI, 1999. http://pastel.archives-ouvertes.fr/pastel-00714249.
Texto completo da fonteAyadi, Mohamed Mondher. "Analyse expérimentale de la génération d'harmoniques dans le bruit d'échappement automobile. Détection par ondelettes et modélisation par approche non linéaire". Paris 6, 2001. http://www.theses.fr/2001PA066260.
Texto completo da fonteAubert, Nicolas. "Étude de lasers microchips pompés par diode, doublés et triplés en fréquence en intracavité". Rennes 1, 2009. http://www.theses.fr/2009REN1E003.
Texto completo da fonteFernandes, Gomes Janaina. "Etude de l'adsorption et électro-oxydation de l'éthanol sur électrodes de platine par spectroscopie de génération de la fréquence somme". Paris 11, 2007. http://www.theses.fr/2007PA112222.
Texto completo da fonteThe possible application of ethanol as a fuel for direct alcohol fuel cells continues to motivate research on the mechanisms of electro-oxidation of ethanol. In this work, the ethanol-platinum interface in acidic medium is investigated using infrared-visible SFG spectroscopy in order to document the intermediates present during the electro-oxidation of ethanol. New evidences of adsorbed intermediates of ethanol oxidation on platinum, never before observed with conventional IR spectroscopy, are reported. Our results show that a secondary ethanol derivative, previously suggested, but never before unambiguously documented, and mono and bidentate acetate, eta2-acetaldehyde, acetyl and a molecular acetic acid derivative are active intermediates of ethanol oxidation in acidic medium. In addition, we report new evidences for the presence of an ethoxy intermediate. The results obtained here also confirm the presence of previously observed ethanol oxidation intermediates: adsorbed CO and a tertiary ethanol derivative. Moreover, we explored the effects of the atomic surface structure of the electrode, alcohol concentration and electrode potential on the mechanism of the adsorption and electro-oxidation of ethanol on platinum. These effects are analyzed through the vibrational spectra of interfacial adsorbed intermediates. Comparison with the adsorption of other simple reactants (methanol, acetaldehyde and acetic acid) in acid medium indicate that even at low potential the platinum surface is highly reactive, producing similar intermediates for all reactants
Loghmari, Zeineb. "Lasers à cascades quantiques InAs / AISb au-delà de 10µm : émission mono-fréquence et génération du THz par différence de fréquences". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS088.
Texto completo da fonteApplications such as gas spectroscopy or medical imaging require light sources emitting in the mid- and far infrared (10 µm<λ < 28 µm) as well as in the THz (λ > 60µm). High-performance, continuous wave regime (CW) and single-frequency emission components are essential for this type of application. Quantum cascade lasers (QCLs) are the only sources that can cover this wide range of wavelengths thanks to their inter-sub-band transitions. However, the performance of LCQs in this wavelength range is often limited by non-radiative transitions. The latter generate mechanisms such as photon absorption by TO phonons or electron relaxation by LO phonons. As a result, laser emission in CW and at room temperature becomes particularly difficult. The objective of this thesis is the development of InAs/AlSb LCQs above 10 µm for single-frequency emission and THz generation by frequency difference. A key point in this work is the use of the InAs/AlSb material system. Their advantage is based on the low effective mass. It is 0.023m0 for InAs compared to 0.041m0 for InGaAs and 0.067m0 in GaAs.First, the development of LCQ active regions based on InAs/AlSb emitting at 11µm was carried out. This work made it possible to produce single-frequency DFB sources emitting continuously at 295K and which were used in QEPAS spectroscopy for ethylene sensing. This LCQ has also been transferred to Silicon (Si) substrate. He has demonstrated the world's most efficient LCQ grown directly on Si substrate. The wavelength range ≥ 11µm was also explored. First, by using a dielectric waveguide where this study leads to an active region design at 20µm whose performances exceed the state of the art in the world with continuous operation up to 240K. Then, these technologies were also exploited by using metal-metal waveguides. In this part, the limits of this waveguide were tested. This made it possible to produce a dual-frequency DFB CQL with a metal-metal waveguide emitting two wavelengths in the far infrared for the generation of THz by difference frequency. In this context, the non-linearity of this type of active region has been optimized. The extraction of the THz wave was also studied
Coutaz, Jean-Louis. "Génération renforcée d'une onde optique à fréquence double sur des réseaux de diffraction en argent par excitation résonnante de plasmon de surface". Grenoble INPG, 1987. http://www.theses.fr/1987INPG0024.
Texto completo da fonteFaucher, Olivier. "Génération de rayonnement cohérent dans l'ultra-violet du vide par triplement de fréquence en jet libre supersonique continu d'azote : étude quantitative des phénomènes de résonance". Lille 1, 1991. http://www.theses.fr/1991LIL10009.
Texto completo da fonteVallet, Jean-Claude. "Etude de l'activité M. H. D. D'un plasma de tokamak en régime de génération de courant par une onde à la fréquence hybride inférieure". Grenoble 1, 1986. http://www.theses.fr/1986GRE10096.
Texto completo da fonteAbudabbousa, Ahmed. "OFDM based Time Difference Of Arrival Estimation". Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS112.
Texto completo da fonteThis thesis presents an original solution for extracting, from OFDM communication signals, the information related to the time difference of arrival (TDOA) between two closed transmitters and one receiver. This solution, which shows to be super-resolution, makes it possible to extract TDOA below the Rayleigh limit set by the useful bandwidth.Inthis work, we perform, using a Multiple Inputs Simple Output, channel characterization and modeling for TDOA estimation. By handling these channel frequency responses in different ways, xe minimize different cost functions expresses as the difference between measured channel response and a predefined direct model. For validation, the simulation based on different topologies exhibit results is compared to the Cramer Rao Lower Band. The effects of the multipath are taken into account and some proposed solutions are discussed ans simulated. Moreover, the experimental part of this work validates the direct and inverse models in different channel configurations
Aguillon, François. "Etude de la génération de rayonnement cohérent dans l'ultra-violet très lointain par triplement de fréquence en jet supersonique de monoxyde de carbonne ou d'azote". Paris 13, 1989. http://www.theses.fr/1989PA132004.
Texto completo da fonteSanaur, Sébastien. "Elaboration d'une expérience d'autodoublage de fréquence en solution de matériaux organiques multifonctionnels". Paris 6, 2003. http://www.theses.fr/2003PA066300.
Texto completo da fonteAbudabbousa, Ahmed. "OFDM based Time Difference Of Arrival Estimation". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS112/document.
Texto completo da fonteThis thesis presents an original solution for extracting, from OFDM communication signals, the information related to the time difference of arrival (TDOA) between two closed transmitters and one receiver. This solution, which shows to be super-resolution, makes it possible to extract TDOA below the Rayleigh limit set by the useful bandwidth.Inthis work, we perform, using a Multiple Inputs Simple Output, channel characterization and modeling for TDOA estimation. By handling these channel frequency responses in different ways, xe minimize different cost functions expresses as the difference between measured channel response and a predefined direct model. For validation, the simulation based on different topologies exhibit results is compared to the Cramer Rao Lower Band. The effects of the multipath are taken into account and some proposed solutions are discussed ans simulated. Moreover, the experimental part of this work validates the direct and inverse models in different channel configurations
Yousfi, Ismail. "Caractérisation de l’endommagement thermique et mécanique dans le mortier par les ondes acoustiques non linéaires". Thesis, Ecole centrale de Lille, 2015. http://www.theses.fr/2015ECLI0009/document.
Texto completo da fonteThe objective of this work is the characterization of heat and mechanical damage in the mortar by the nonlinear acoustic waves. The correlation between non-linear/linear acoustic parameters and damage in mortar is studied based on experiments and modelling. For the heat damage, cylindrical specimens were prepared and were characterized by studying the porosity and saturation. Indeed, the linear acoustic (UPV) and non-linear acoustic (Higher harmonic generation) were applied to characterize the damage. The linear acoustic tests have shown that velocities and modulus of Young of the mortar decreases in function of the temperature. The non-linear acoustic tests have shown that beta increases in function of the temperature.For the mechanical damage. The self-healing phenomenon was characterized by the permeability and the acoustic tests. Indeed, the permeability tests have shown that the airflow and the crack size decreases quickly in the first month then slowly for the rest of the self-healing process. On the other hand, the non-linear acoustic tests shown that the alpha and beta decreases according to the self healing process which means that the nonlinear parameters are a good indicators to characterize the self-healing. Moreover, the analysis of the experimental results indicates that the frequency resonant technique is more efficient to characterize the defects in the mortar than the higher harmonic generation. A polynomial correlations of a 2nd degree was established between the nonlinear parameters and the index damage. The findings of this work should be most appropriate as a foundation for the study of the self healing by the nonlinear acoustic waves
Dalstein, Laetitia. "Etude par spectroscopie optique non linéaire du couplage entre plasmon de surface de nanoparticules métalliques et excitation vibrationnelle de molécules adsorbées à leur surface". Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS222/document.
Texto completo da fonteOptical properties of metallic nanoparticles, exhibiting a surface plasmon resonance (SPR) in the visible range, are nowadays extensively used to detect and characterize chemical entities, either in solution or deposited on substrates (e.g. sensors). In this work, I have optimized the creation of interfaces composed of 15nm in diameter gold nanoparticles on silicon and glass substrates after functionnalization by silanes, and their chemical and optical characterization by linear and nonlinear optical methods. I have used UV-visible spectroscopy in reflexion and transmission geometries, coupled to electronic and atomic force microscopies, with the help of optical simulations, to correlate the optical properties of the particles to their local density at the surface. Nonlinear sum frequency generation spectroscopy is able to probe the surface chemistry of both the particles and the substrate, through a local amplification of optical processes due to the excitation of the SPR. After showing that the latter does indeed amplify the low intensity molecular SFG signals from the silane layer, I have revealed the presence, in the organic layer, of unreacted methyl groups arising from an incomplete silanization, evidenced the link between plasmonic and chemical stability in time and laser irradiation, finely assessed the quality of surface functionnalization of the particles by thiols, and established the linear relationship between linear and nonlinear optical responses at the surface. Finally, I have directly studied the amplification process itself by coupling to the SPR through two dimension spectroscopic studies in the visible and infrared ranges. I have shown that the coupling is indeed measurable, even on small deposited particles, and that it happens in the spectral zone where the surface plasmon exists (from green to red). A comparison to flat platinum and gold surfaces leads to a fine estimation of amplification factors, which correspond to the predictions of a simple model for the plasmonic processes at stake at such interfaces
Yousfi, Ismail. "Caractérisation de l'endommagement thermique et mécanique dans le mortier par les ondes acoustiques non linéaires". Thèse, Université de Sherbrooke, 2015. http://hdl.handle.net/11143/7941.
Texto completo da fonteRésumé : L'objectif de ce travail est la caractérisation de l’endommagement thermique et mécanique dans le mortier par les ondes acoustiques non linéaires. La corrélation entre les paramètres acoustiques linéaires et non linéaires est basée sur les essais expérimentaux et la modélisation. Des mesures expérimentales des paramètres acoustiques non linéaires en fonction de la taille de la fissure et la température ont été effectuées sur mortier. Les vitesses ont montré une diminution et les paramètres non linéaires ont montré une augmentation en augmentant le degré de fissuration. Pour l’endommagement thermique, des éprouvettes cylindriques ont été préparées et ont été caractérisées par l'étude de la porosité et de la saturation. L'acoustique linéaire (UPV) et l’acoustique non linéaire (génération d'harmoniques) ont été appliquées afin de quantifier l’endommagement. Les essais acoustiques linéaires ont montré que les vitesses transversales, longitudinales et le module d'Young du mortier diminuent en fonction de la température. Les essais acoustiques non linéaires ont montré l'augmentation du bêta est fonction de l’endommagement thermique. Pour l’endommagement mécanique et l'autocicatrisation, des anneaux de mortier ont été préparés et fissurés en contrôlant la taille de chaque fissure. Ensuite, le phénomène d'autocicatrisation est suivi par la perméabilité et des essais acoustiques. Les essais de perméabilité ont montré que le débit d'air et la taille de la fissure diminuent rapidement au cours du premier mois, puis lentement durant le reste du processus d'autocicatrisation. D'autre part, les tests acoustiques non linéaires ont montré que « alpha » et « bêta » diminuent durant le processus de l’autocicatrisation, ce qui signifie que les paramètres non linéaires sont des bons indicateurs pour caractériser ce phénomène. En outre, l'analyse des résultats expérimentaux indique que la technique de résonance de fréquence est plus efficace pour caractériser les défauts dans le mortier que la génération d'harmoniques plus élevés. À partir des essais expérimentaux et dans le but d'obtenir un résultat plus général indépendant de notre cas d’étude, les paramètres non linéaires ont été liés à un index d’endommagement. Une corrélation polynomiale de 2e degré a été établie entre les paramètres non linéaires et l’index d’endommagement. Un modèle numérique basé sur la méthode des volumes finis a été proposé afin d'établir une corrélation entre la taille de la fissure et le flux d'air. Les résultats numériques ont été comparés avec les résultats des tests de perméabilité et montré un bon accord. Les résultats de ce travail représentent un bon départ pour étudier le phénomène de l'autocicatrisation par les ondes acoustiques non linéaires.
Hergott, Jean-François. "Optimisation de la génération d'harmoniques d'ordre élevé et application à l'interférométrie UVX résolue en temps". Phd thesis, Université Paris Sud - Paris XI, 2001. http://tel.archives-ouvertes.fr/tel-00081880.
Texto completo da fonteDans une première partie, nous présentons une étude approfondie de l'optimisation du flux harmonique produit soit dans une fibre creuse soit dans un jet. Dans chacun des cas, nous déterminons les facteurs limitant l'émission : accord de phase, absorption, ionisation, défocalisation. La comparaison des profils d'émission avec les simulations démontre le rôle crucial de la phase du dipôle atomique pour la génération dans une fibre. L'optimisation dans un jet conduit à des efficacités de conversion allant de 10-5 à 50nm (1010 ph/imp) à 10-7 à 15nm (5.107 ph/imp).
Dans une deuxième partie, nous étudions la focalisation du rayonnement harmonique par une lentille de Bragg-Fresnel, qui permet une focalisation efficace hors axe, sans aberration. Nous mesurons pour l'harmonique 39 une tache focale de l'ordre de 2µm. Compte tenu du flux élevé et de la courte durée (femtoseconde) des harmoniques, des éclairements élevés dans l'UVX peuvent être atteints.
Finalement, nous présentons les premières expériences de diagnostic de plasma par interférométrie UVX utilisant le rayonnement harmonique. Une technique originale est développée à partir de 2 sources harmoniques mutuellement cohérentes séparées spatialement. L'analogue temporel de l'interférométrie spatiale, qui utilise 2 impulsions harmoniques séparées en temps, est également démontré. Cette interférométrie fréquentielle a permis le premier diagnostic UVX de l'évolution temporelle d'un plasma avec une résolution femtoseconde. Une extension du schéma de 2 à 4 impulsions permet de mesurer avec une sensibilité extrême un déphasage équivalent à une demi-période harmonique, soit des écarts temporels à l'échelle attoseconde (1as=10-18s).
Nasser, Youssef. "Sensibilité des systèmes OFDM-CDMA aux erreurs de synchronisation en réception radio-mobile". Phd thesis, Grenoble INPG, 2006. http://tel.archives-ouvertes.fr/tel-00214147.
Texto completo da fonteLa thèse consiste à étudier en premier lieu les performances des différents types de combinaisons de l'OFDM et du CDMA, appelées sous le nom générique « OFDM-CDMA », dans un environnement parfaitement synchronisé dans une liaison descendante avec les mêmes conditions de transmission : charge du système, constellation, rendement du codage.
Une fois la comparaison des différents systèmes établie dans un contexte parfaitement synchronisé, on traitera le problème des imperfections de transmission : erreurs des synchronisation, imperfections Radio Fréquences (RF), estimation du canal, effet Doppler.
Les différents types d'erreurs de synchronisation étudiés dans le manuscrit sont la synchronisation de la fenêtre temporelle, la synchronisation des fréquences porteuse, et d'échantillonnage.
Les imperfections RF étudiées consistent en le bruit de phase et la gigue d'horloge.
Les sensibilités de l'OFDM-CDMA à ces erreurs sont évaluées en fonction du Rapport Signal à Interférence plus Bruit (RSIB) en sortie du détecteur en tenant compte de l'orthogonalité entre les codes d'étalement.
Finalement, on s'intéresse à évaluer les performances de ces systèmes en terme du Taux d'Erreur Binaire (TEB) en sortie du décodeur et à faire le lien entre le RSIB en sortie du détecteur et le TEB en sortie du décodeur.
En conclusion de ce travail, on peut tirer des limites tolérées sur les imperfections de transmission de ces systèmes ainsi qu'une comparaison entre leurs performances.
Sabriana, Ortega Georgia Irai. "Développement de méthodes analytiques pour la détermination de l’isotopie du plomb et des éléments traces dans des produits pétroliers (huile, asphaltène, kérogène, roche mère). Application à la datation de la génération du pétrole et de la déposition de la roche mère dans un bassin pétrolier". Thesis, Pau, 2012. http://www.theses.fr/2012PAUU3043/document.
Texto completo da fonteTiming crude oil generation and source rock deposition provides important clues in petroleum prospection. In this work, different analytical procedures were developed for trace metals and Pb isotope ratio were determination crude oils and related products. These analytical strategies were then used, for the first time, to assess the applicability of the U-Th-Pb geochronometers for timing source rock deposition age and crude oil generation in the Illinois Basin. Ages determined are in good agreement with those predicted by geological numerical models, demonstrating the potential of these geochronometers to study the history of hydrocarbons formation and to find new hydrocarbon sources