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Fall, Abdoulaye. "Réflectométrie optique dans le domaine fréquentiel pour l’analyse des réseaux locaux domestiques optiques". Thesis, Evry, Institut national des télécommunications, 2016. http://www.theses.fr/2016TELE0011/document.
Pełny tekst źródłaIn order to develop high capacity future-proof home network, the FUI 12 RLDO project suggests passive star network topology using multimode couplers. This topology encounters implementation difficulties due to the non-uniformity of the power distribution in the output ports of multimode couplers. Analyzing this problem shows that the properties of modes propagating in the network elements plays a key role in this non-uniform characteristics of multimode couplers. In order to characterize these modes propagating in the network, we have developed a complex optical frequency domain reflectometry (OFDR) setup. The phenomena limiting the sensitivity to the phase in OFDR – in fact, those related to the non-linear frequency tuning of the laser source - are investigated to contribute to a better understanding of the limiting mechanisms. Then we have tested the intensity and phase measurement performance of the developed setup. Later, we studied the optimal resolution conditions to characterize the modes in a multimode waveguide. We have also analyzed the uncertainty of the measurement of the chromatic dispersion of modes in case where it is impossible to determine whether one or several modes are present in a given dispersion curve. Additionally, we have introduced an adaptive time-frequency method, to obtain the dispersion curves with optimal resolution. This method allows us to show the versatility of the special RLDO multimode fiber (single-mode behavior under single-mode excitation at 1310 nm and 1550 nm). The analysis of the propagation in the optical fibers, associated with a model we have developed to study the behavior of multimode couplers, has permitted to explain encountered difficulties with the experiments of the multimode passive star network topology. This also gives insights to develop a functional prototype of network
Fall, Abdoulaye. "Réflectométrie optique dans le domaine fréquentiel pour l’analyse des réseaux locaux domestiques optiques". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2016. http://www.theses.fr/2016TELE0011.
Pełny tekst źródłaIn order to develop high capacity future-proof home network, the FUI 12 RLDO project suggests passive star network topology using multimode couplers. This topology encounters implementation difficulties due to the non-uniformity of the power distribution in the output ports of multimode couplers. Analyzing this problem shows that the properties of modes propagating in the network elements plays a key role in this non-uniform characteristics of multimode couplers. In order to characterize these modes propagating in the network, we have developed a complex optical frequency domain reflectometry (OFDR) setup. The phenomena limiting the sensitivity to the phase in OFDR – in fact, those related to the non-linear frequency tuning of the laser source - are investigated to contribute to a better understanding of the limiting mechanisms. Then we have tested the intensity and phase measurement performance of the developed setup. Later, we studied the optimal resolution conditions to characterize the modes in a multimode waveguide. We have also analyzed the uncertainty of the measurement of the chromatic dispersion of modes in case where it is impossible to determine whether one or several modes are present in a given dispersion curve. Additionally, we have introduced an adaptive time-frequency method, to obtain the dispersion curves with optimal resolution. This method allows us to show the versatility of the special RLDO multimode fiber (single-mode behavior under single-mode excitation at 1310 nm and 1550 nm). The analysis of the propagation in the optical fibers, associated with a model we have developed to study the behavior of multimode couplers, has permitted to explain encountered difficulties with the experiments of the multimode passive star network topology. This also gives insights to develop a functional prototype of network
Palaysi, Jérôme. "Problèmes algorithmiques dans les réseaux tout-optique". Montpellier 2, 2002. http://www.theses.fr/2002MON20173.
Pełny tekst źródłaTogni, Olivier. "Force des graphes : indice optique des réseaux". Bordeaux 1, 1998. http://www.theses.fr/1998BOR10596.
Pełny tekst źródłaMarin, Emmanuel. "Modélisation des effets des réseaux de Bragg dans les composants à fibres optiques". Saint-Etienne, 2000. http://www.theses.fr/2000STET4004.
Pełny tekst źródłaPhotosensitivity in optical fibres has been highlighted in the last two decades ; permitting the realization of index modulations in fibres cores (i. E. Bragg gratings). Although the mechanisms underlying photosensitivity remain obscure, this proterty can be ascribed to defects showing UV absorption peaks. Then, by generating an interference field in the UV region and placing a fibre or a fibre-based structure within it can write a Bragg grating. We present in this thesis tolls to predict Bragg gratings effects in complex optical fibre-based structure. Firstly, we introduce the analysis of propagation in optical fibres and fibre-based couplers. We detail the approach used (supermode theory) to analyse waveguides of complex goemetry and we present various numerical methods used to calculate scalar modes of waveguides. .
Fen, Zhou. "Routage multicast tout optique dans les réseaux WDM". Phd thesis, INSA de Rennes, 2010. http://tel.archives-ouvertes.fr/tel-00541116.
Pełny tekst źródłaZiebell, Melissa. "Transceiver optique en silicium pour les réseaux d'accès". Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00873582.
Pełny tekst źródłaZiebell, Melissa. "Transceiver optique en silicium pour les réseaux d’accès". Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112181/document.
Pełny tekst źródłaSilicon photonics is a research field in full expansion that works towards the integration of photonics and microelectronic components in a single chip. The creation of a broadband optical link that is able to carry high-speed information requires the development of efficient building blocks compatible with CMOS technology. The work carried out during my Ph.D. focused specifically on silicon optical modulators for high-speed applications from 10 to 40 Gbit/s. The work presented includes design, optimization, fabrication and characterization of the complete device. The modulator is based on the electro-refractive effect obtained by depletion of carriers in PN and PIPIN diodes to obtain a phase change of the optical mode. Intensity modulation is obtained by integration of the active region in a Mach-Zehnder interferometer or a ring resonator. Electrical, optical and radio frequency simulations were conducted on the various elements of the modulator to design a device for FTTH (Fiber To The Home) applications operating at 127 µm. Additional studies included the design of RF coplanar waveguide electrodes optimized through the development of an electro-optical model that takes into account the propagation of the electrical and optical waves in the active region. Compatible CMOS processes were proposed, and the necessary masks for fabrication were designed considering fabrication tolerances and critical parameters. Finally, various experimental results were obtained on components designed at IEF and fabricated at CEA-LETI. We can specially mention a Mach Zehnder modulator operating at 40 Gbit/s that uses a PIPIN diode to obtain an index variation, and having an extinction ratio of 7.5 dB and losses of only 6 dB. The goal of future optimizations of silicon modulator is to integrate these devices with the RF driver, and to move towards more complex and efficient modulation formats than the two-level intensity modulation seen so far
Zhou, Fen. "Routage multicast tout optique dans les réseaux WDM". Rennes, INSA, 2010. https://tel.archives-ouvertes.fr/tel-00541116.
Pełny tekst źródłaIn this thesis, we studied the all-optical multicast routing (AOMR) problem in wavelength-routed WDM networks. With respect to the delay and link stress sensitive AOMR, an efficient algorithm based on avoiding multicast incapable branching nodes in light-trees is proposed. This algorithm is shown to be able to find a good tradeoff among the end-to-end delay, the link stress and the total cost. Regarding the power-aware AOMR, a more accurate and realist power loss model is defined for all-optical multicasting. Based on this new model, the power optimal design of light-trees is formulated by a mixed-integer programming (MILP). To achieve so, a set of novel linear equations is introduced to replace the nonlinear ones induced by the light splitters. In order to analyze the AOMR heuristic algorithms and assess their performances, the cost bounds of multicast light-trees and the approximation ratios of heuristic algorithms are derived mathematically in both unweighted and non-equally weighted WDM mesh networks. Concerning the cost optimal AOMR, a new structure called light-hierarchy is proposed. It is proven that the optimal structure is not the light-tree but the proposed light-hierarchy. Simulation results strongly suggest the employment of light-hierarchy for AOMR in WDM networks with sparse splitting
Diaz, Luque Julia. "Dynamique dans un réseau optique conservatif". Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10047/document.
Pełny tekst źródłaOptical lattices are structures created by the interference of laser beams, which make it possible to trap and arrange cold atoms. They have become a model system for several domains in physics, because it is possible to simulate other systems by changing the lattice geometry and its parameters. These characteristics are easy to modify experimentally. In particular, it is possible to obtain conservative optical lattices. In this thesis, we study the dynamics of an atom trapped in a 2D conservative optical lattice. The dynamics of the atom depends on the parameters of the lattice, and it is often complex. In consequence, this thesis is at the interface between the domains of cold atoms and non-linear dynamics. The study of the dynamics in the optical lattice needs to be done firstly in the classical limit. We examine in the first place the solutions to the movement equations obtained by numerical integration, for the different configurations of the system. They show a big variety of possible dynamical regimes. Amongst these regimes we find synchronization phenomena leading to a periodic movement locked in frequency. Synchronization seems to inhibit chaos in the system. The main solutions obtained numerically are also studied analytically. This approach allows us to obtain a description of the movement for the different dynamical regimes observed. All these regimes are easy to reproduce experimentally and the influence of synchronization on the existence of chaos needs to be studied. Additionally, this classical analysis serves as a basis for studying the system in the quantum limit
Shu, Da. "Réseaux résonnants accordables pour filtrage optique à bande étroite". Phd thesis, Ecole centrale de Marseille, 2012. http://tel.archives-ouvertes.fr/tel-00781178.
Pełny tekst źródłaAmaya, Mohammad. "Amélioration des performances d'un amplificateur optique à semi-conducteurs par injection optique à la transparence du gain pour les réseaux de télécommunications optiques". Brest, 2006. http://www.theses.fr/2006BRES2025.
Pełny tekst źródłaSemiconductor optical amplifier (SOA) is an attractive component for future metropolitan multicolor all-optical telecommunication networks. This work focuses on the theoretical and experimental study of the SOA static and dynamic performances, when injecting a continuous wave (CW) high power as a holding beam (HB) at the gain transparency wavelength into its cavity with the aim of pointing out the interesting effects of this technique. Our work has shown that employing the holding beam, improves the soa saturation output power, the carrier lifetime and the device gain recovery time, over a wideband of incident signal wavelengths and powers without sacrificing the amplifier gain level neither degrading its noise figure (NF). Our theoretical and experimental results point out that injecting the holding beam in counter-propagative configuration with respect to the optical incident signal is more efficient than that in co-propagative one. We have employed the holding beam injection in an SOA based WDM multichannel transmission system with the purpose of reducing the cross-gain modulation (XGM) induced inter-channel crosstalk, hence, of improving the signals bit error rate (BER). Finally, a simulation model which gives results close to the measured ones has been obtained during this work as well
Naciri, Youssef. "Synchronisation de paquets optiques dans les réseaux de télécommunications : réalisation d'un module exploitant l'interaction acousto-optique". Brest, 2000. http://www.theses.fr/2000BRES2050.
Pełny tekst źródłaBlanchard, Pierre. "Mesure des réflexions sur fibre optique par réflectométrie optique temporelle : Application aux réseaux de capteurs analogiques". Limoges, 1991. http://www.theses.fr/1991LIMO0120.
Pełny tekst źródłaLiu, Qin. "Performance du routage par déflexion pour les réseaux tout optique". Versailles-St Quentin en Yvelines, 1999. http://www.theses.fr/1999VERS0020.
Pełny tekst źródłaFafchamps, Damien. "Communications numériques dans les réseaux d'accès optique : modélisation, codage, performances". Paris, ENST, 2010. http://www.theses.fr/2010ENST0083.
Pełny tekst źródłaOptical communications got involved in techniques emerging from information theory very recently with the introduction of error correcting codes in 10 Gbitsls systems in the late 90s. Ever since then, attempts of adapting advanced code schemes has been on the increase such as concatenated convolutional codes, LDPC or Turbo codes. These are prospective works that have not led to standards yet. One of the necessary conditions for the optimization of digital communication systems is to adapt digital techniques to the communication channel. So coding schemes must be adapted to the optical context but modelization of the optical channel is completely different from the radio channel. This thesis is interfacing the domain of optical communications and the information theory applied to coding. This work led to a proposal cstatistical model describing the optical channel and aiming at combining precision and analytical simplicity in order to keep the model workable for coding. This model has been verified in the context of a three-year project dealing with the study and prototyping of an optical metropolitan network (ECOFRAME). Our contribution consists of the implementation of a simulator which allowed us to validate the theoretical model of the optical channel and to study the impact of the network configuration on the signal statistics. We highlighted decision strategies and decoding schemes adapted to the optical channel. In collaboration with ENSIL, we pointed out the impact of the channel modelization on LDPC codes performance in optical
Aboujeib, Joumane. "Systèmes de commutation optique à base d'une cellule acousto-optique multi-transducteurs pour les réseaux de télécommunications : optimisation et caractérisation". Brest, 2008. http://www.theses.fr/2008BRES2015.
Pełny tekst źródła“All optical networks”, with optical routing and switching components, seems to be the way for telecommunication networks development. This work deals with the characterizations of free space optical packet switches based on acousto-optic technology. The adopted solution is the use of a Bragg cell in which two diffraction gratings can be superimpose simultaneously. The switch is made with a TeO2 crystal provided with piezoelectric planas phased array transducers, and a specific electronic command. In the first part of this work, we present the optical switching function in optical networks, and various technologies used to realize this function. Then, we recall the physical acousto-optic interaction in the Bragg regime, the operating principle of the rnulti-transducers acousto-optic cell, and the consequences of the superposition of two diffraction gratings in a single crystal. In a second section part, we present the design of the 2x2 switch. We study experimentally the spurious effects at the cell output and we deduce the switch crosstalk. After the optimization of the switch, the system is characterized. The measurements show that die switch presents low crosstalk, low switching time, low sensitivity to the polarization, and transparency with the transmission rate. We show in the last part, that using a Bragg cell with planar phased array transducers driven by an appropriate electronic command (based on the direct synthesis of frequency) allows to improve the bandwidth of the deflector compared to other solutions proposed in the literature
Calvet, Jean-Thierry. "Synchronisation des réseaux optiques SDH". Paris 6, 2003. http://www.theses.fr/2003PA066039.
Pełny tekst źródłaHoule, Alain C. "Capteur optique de courant pour les réseaux à très haute tension". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0020/NQ46633.pdf.
Pełny tekst źródłaChannoufi, Malèk. "Modélisation et optimisation de la couche optique de réseaux sur puce". Thesis, Cergy-Pontoise, 2014. http://www.theses.fr/2014CERG0692/document.
Pełny tekst źródłaThe developing of complex System on Chip "SoC" interconnecting different cores IP distant in micrometer chip scale, needs important data bandwidth , low latency and the best compromise between optical power loss and crosstalk. According to that, finding new methodology design is necessary to cope to those challenges.Using centric communication becomes the mainly solution to improve communication performance in system on chip and recently many researches are focusing on Optical Network on Chip 'ONoC'.In this thesis, a novel architecture of an optical network on chip is proposed, this architecture is reposed on 2 design paradigms: ONoC based 3D chip and multilevel waveguides based ONoC. The key element of this architecture is the multilevel microresonator (Si/SiO2) which is the optical switch of the network. Optical wave behavior in different geometries have been studied using FEM method in order to find compromise between optical power loss and crosstalk. Operation mode of this ONoC called "OMNoC" is explained, routing protocol is studied using NS-2 simulator too, then optimized and developed using C++ and Benchmark tool. After that and by using FEM results and adopted routing strategy, OMNoC performances are studied and compared with other network architectures proposed in ONoC literature. In conclusion and according to performances analysis and comparisons, OMNoC could be considered as a promising network architecture which offer scalability and give a compromise between optical power loss and crosstalk
Yavand, Hasani Javad. "Conception de front end RF pour les réseaux d'objets communicants sans fils". Université Joseph Fourier (Grenoble), 2008. http://www.theses.fr/2008GRE10312.
Pełny tekst źródłaThis work is an attempt toward low-power mm-wave transceiver design for low cost, short range, low data rate and dense Wireless Sensor Network (WSN) application, using standard CMOS90nm technology. Due to leak of RF models in the library of the foundry design kit, we developed individual models for MOS transistor and passive elements. Proper layout proposed for MOS transistors and layout-dependent parasitic effects, as weIl as the substrate effects were studied, analyzed and modelled accurately. To overcome the problems with inductors in bulk CMOS technology, we proposed a novel line-type inductor structure. To ob tain the best performance of the inductors, an accurate RLGC model was developed and analytic equations were used for calculation of the model parameters. Lumped element model was evaluated using electromagnetic simulator of ADS and HFSS software. We designed a single stage cascade LNA using Power Constrained Simultaneous Noise and Input Matching (PCSNIM) technique. The LNA was fabricated in the STMicroelectronics 90nm CMS_GP process in 2006. Measurement results showed lOdB power gain and 4. 7dB noise figure with only 3mW power consumption. The chip area of our LNA is 0. Lmm2, a record among the reported Ka band LNA's. We developed simple low power transceiver architecture, with good performance. The receiver was simulated in MATLAB and -87dBm sensitivity, 890KHz bandwidth, with 6. 65mW power consumption are obtained. The transmitter was designed as simple as possible, using power oscillator idea, delivering 6m W RF power to the antenna. The transmitter has 25% power efficiency, very good result in comparison with the reported works
Naoum, Rafah. "Etude d'un capteur angulaire en optique intégrée : nouveau système d'enregistrement des réseaux holographiques". Limoges, 1987. http://www.theses.fr/1987LIMO0055.
Pełny tekst źródłaParvery, Hervé. "Contribution à l'étude d'antennes réseaux large bande à pointage pilote par commande optique". Limoges, 2002. http://www.theses.fr/2002LIMO0031.
Pełny tekst źródłaThis thesis concerns the study, the realisation and characterisation of an antenna array fed and steered by an optical command. The array is fed by "true time delays". Three systems are proposed. The first one works at 960 MHz and allows to validate the control of the array pointing direction by tuning the optical wavelength that carries the microwave signal. The second antenna presents a wide bandwidth around 2 GHz (25%) and demonstrates that the pointing direction of the array remains invariant with the emitted frequency. The last studied corresponds to the conception and to the realisation of a prototype working in the millimetre-wave domain. It is based on the previous system used at low frequency, to create the delays, which is associated to microwave mixing to produced out of phase millimetre-waves. The interest of this system is to obtain a wide bandwidth control of the pointing direction and to simplify the feed circuit of the radiating elements
Buet, Xavier. "Nouvelles architectures de réseaux résonants pour la stabilisation de diodes laser". Phd thesis, Université Paul Sabatier - Toulouse III, 2012. http://tel.archives-ouvertes.fr/tel-00762103.
Pełny tekst źródłaRobert, Stéphane. "Caractérisation optique de réseaux de diffraction submicroniques par des techniques génétique et neuronale". Saint-Etienne, 2003. http://www.theses.fr/2003STET4008.
Pełny tekst źródłaRecent development in the field of grating fabrication with submicrometer period leads to reach the resolution limit of classical microscopic caracterization techniques. New methods need to be finalised to produce a good checking of the realised structures. The resolution of the inverse scattering problem can be a good alternative. Thus, it is possible to reconstruct the grating profile from a set of diffracted efficiencies orders called optical signature under some hypothesis. The efficiency of two methods based respectively on the use of a genetic algorithm and a neural network is experimentally demonstrated. The first one is a robust and flexible technique. On the other hand, the speed of the second one permits to accomplish a control of the grating homogeneity
Le, Bras Hughes. "Etude des réseaux radio sur fibre dans le contexte des réseaux d'accès et privatifs". Paris 6, 2008. https://tel.archives-ouvertes.fr/tel-00812485.
Pełny tekst źródłaMartin, Philippe. "Réseaux de neurones artificiels : application à la reconnaissance optique de partitions musicales". Phd thesis, Grenoble 1, 1992. http://tel.archives-ouvertes.fr/tel-00340938.
Pełny tekst źródłaLourdiane, Mounia. "CDMA à séquence directe appliqué aux systèmes de communications optiques". Phd thesis, Télécom ParisTech, 2005. http://pastel.archives-ouvertes.fr/pastel-00001398.
Pełny tekst źródłaHumbert, Georges. "Etude et réalisation de composants passifs tout-fibre : réseaux longue période par arc électrique". Rouen, 2002. http://www.theses.fr/2002ROUES058.
Pełny tekst źródłaLong period fibre gratings are passive components used in optical telecommunication or instrumentation fields. The gratings are obtained by creating a modulation of the opto-geometrical fibre parameters with a periodicity of few hundred micrometers. They induce at a resonance wavelength, a co-directional coupling between the fundamental mode and a cladding mode. A large bandwidth filter is thus obtained. A theoretical study based on coupled mode theory is realised, so as to dissociate the influence of their several parameters on the transmitted spectrum. Simulations of complex long period fibre gratings are also presented. In this study, the gratings are fabricated by applying electrical discharges on the optical fibre. The properties of this new method are deeply investigated with the help of several characterisations. One of the interests of this method is to make pass-band filters by introducing phase shifts in the gratings. The association of the grating properties with those of special optical fibres (dual concentric cores fibre, Ge-free air-silica microstructure fibre) is also investigated. Finally, a new process for making fused fibre couplers using a CO2 laser as heating source, is presented in annex
Fawaz, Wissam. "Le cycle de vie de service dans les réseaux optiques nouvelles générations". Paris 13, 2005. http://www.theses.fr/2005PA132034.
Pełny tekst źródłaChauveau, Clément. "Réseaux de résonateurs pour la photonique sur silicium, applications au multiplexage en longueur d'onde". Troyes, 2012. http://www.theses.fr/2012TROY0036.
Pełny tekst źródłaThe development of the micro-electronics industry has given access to very high data transmission rates. Currently, these data rates are limited by the electrical interconnection bandwidth and it will soon be necessary to use optical links to obtain higher data rates. To attain this objective, new building blocks must be developed such as lasers, modulators, photo-detectors, wave-guides and routing devices which must all be fully compatible with the CMOS processing. This doctoral thesis concerns the study and development of new components based on circular resonators arrays, which offer alternative solutions to existing devices in the field of wavelength division multiplexing for silicon photonics. The study of single ring resonators over the entire surface of a wafer shows that the use of thermal regulation is required to compensate for fabrication variations. Results of simulations and experiments show that arrays of circular resonators allow broadband filtering with very low loss. Based on this principle, an 8 channel multiplexer is demonstrated conforming to telecoms specifications. This kind of device is a potential candidate for use in the development of wavelength division multiplexing in silicon photonics
Fsaifes, Ihsan. "Encodage et Décodage Temporels "Tout-Optique" à Réseaux de Bragg pour l'Accès Multiple". Phd thesis, Télécom ParisTech, 2007. http://pastel.archives-ouvertes.fr/pastel-00005525.
Pełny tekst źródłaLecoche, Frédéric. "Modélisation et simulation de noeuds de routage optique dans les réseaux dorsaux hybrides". Télécom Bretagne, 2008. http://www.theses.fr/2008TELB0064.
Pełny tekst źródłaRecently, consumers' and organizations' appetence in terms of numerical data usage has led to the rapid development of optical transport networks. The services offered to users are requiring more and more in terms of bandwidth. The introduction of optical transparency within the networks makes for more flexible networks and higher bit rates. The hybrid optical cross-connects (OXC) thanks to their all optical switching afford transparency and allow the electrical regeneration (through dedicated ports)of canals whose quality is believed to be insufficient from the physical parameters of transmission. In this study, two OXC architectures were chosen, one based on an optical switching matrix and the other based on Wavelength Selective Switch (WSS). This research study highlights the modelling and simulation of these two architectures using an optical transmission simulator (VPI TM). The first part of this study presents the general approach to the modelling and the simulation of a device and of optical equipment. The switching devices are modelised taking into consideration the transmission parameters used for the estimation of a canal's quality. After functional validation of the spatial switching and of their elementary static characteristics as well as systems test, the switching models are implemented in OXC working on WDM (50 and 100 GHz) spectra
Lemarchand, Fabien. "Etude et réalisation de réseaux de diffraction pour le filtrage optique bande étroite". Aix-Marseille 3, 1999. http://www.theses.fr/1999AIX30082.
Pełny tekst źródłaA diffraction grating deposited above a dielectric guide makes it possible to couple the incident light for a particular wavelength and a particular incidence. The spectral response of such an hybrid structure, called as resonant grating, presents a peak in reflectivity which can reach 100 % when the period of the grating is lower than the wavelength. We take advantage of this resonance effect for not ch filtering applications. The numerical calculation of the efficiency of these components reveals the principal deffect : the high sensitivity to the incident angle. Inorder to improve the angular tolerance, we study the modification of the dispersion curves induced by the periodic perturbation. We show that it is possible to optimize the geometry of the component to dissociate the spectral width of the angular width. The spectral characterization of the first achievements shows that these hybrid structures combine a very narrow bandwitdth and a very broad band of rejection, essential criteria for the applications of filtering in the optical telecommunication field. Last, we numerically study the radiation of a dipole located inside these hybrid structures. Their capacity of coupling makes it possible to extract the light emitted by a luminescent atom in the guided modes of a dielectric microactivity. Moreover, the angular selectivity of resonant gratings is an asset to make this radiation directive
Fracasso, Bruno. "Des interconnexions holographiques à l'aiguillage dynamique pour les réseaux de communications optiques". Habilitation à diriger des recherches, Université de Bretagne Sud, 2010. http://tel.archives-ouvertes.fr/tel-00691577.
Pełny tekst źródłaSuleiman, Maha. "Conception d'un capteur optoélectronique par interférométrie à rétro-injection optique pour la démodulation des signaux de fibres optiques à réseaux de Bragg". Toulouse, INPT, 2008. http://ethesis.inp-toulouse.fr/archive/00000702/.
Pełny tekst źródłaIn this thesis, we propose post-transforms for the compression of satellite images. After the wavelet transform, each block of coefficients is further transformed in a basis selected among a dictionary by minimization of a rate-distortion criterion. First, we optimize the bandelet transform parameters, from which the post-transforms derive, for the compression of satellite images. Next, we analyze dependencies between wavelet coefficients that are not exploited by the bandelet transform and we define new post-transform bases. Bases build by PCA minimize the correlations between post-transformed coefficients and compact the energy of each block on a small number of coefficients. This feature is exploited during the entropy coding process. Last, we adapt the post-transform to progressive compression schemes. We then employ the Hadamard post-transform with the CCSDS image encoder to obtain a low computational complexity yet efficient compression scheme
Al, Zahr Sawsan. "Planification de réseaux WDM translucides avec qualité de transmission garantie". Phd thesis, Télécom ParisTech, 2007. http://pastel.archives-ouvertes.fr/pastel-00004014.
Pełny tekst źródłaLalanne, Philippe. "Les réseaux de neurones formels et leurs réalisations optoélectroniques : génération optique de tableaux de nombres aléatoires". Paris 11, 1989. http://www.theses.fr/1989PA112240.
Pełny tekst źródłaTwo purposes concerning the field of neural networks research are investigated in this thesis. First, we study optical implementation of neural networks. We show that higher order models, i. E. Multineuron synapsis models, allow us to increase strongly the network capacity with respect to the number of stable stored states. Optical implementations of such models necessary suppose both optical interconnects and boolean logic gates built into matrices. We propose a general approach for these implementations. In our hybrid architecture, the strength of optics, linear transformation for massive interconnects and the strength of electronics, point nonlinearities are both used to advantage. In the second part, we use speckle as a fast binary random number arrays generator. A theoretical approach and experimental evidences show that this kind of random generator may be of interest for optoelectronic implementation of parallel stochastic algorithms
Terrier, Hugo. "Étude théorique des collisions ultra-froides en réseau optique". Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S028/document.
Pełny tekst źródłaAn optical lattice, created by lasers, can trap atoms cooled to ultra-low temperatures. It provides a constraint as if it were a perfect crystal (a crystal without thermal agitation). I describe the states of particles in a periodic potential (optical network) using probability waves (quantum physics) stationary (independent theory of time). The wave nature of the material is exacerbated at very low temperatures and gives rise to interference phenomena and individual resonance
Abbal, Laurent. "Analyse vectorielle des réseaux étendue aux composants optiques et optoélectroniques". École nationale supérieure de l'aéronautique et de l'espace (Toulouse ; 1972-2007), 2002. http://www.theses.fr/2002ESAE0020.
Pełny tekst źródłaCoudert, David. "Algorithmique et optimisation de réseaux de communications optiques". Phd thesis, Université de Nice Sophia-Antipolis, 2001. http://tel.archives-ouvertes.fr/tel-00008087.
Pełny tekst źródłaDans un premier temps, nous étudions l'implantation en espace libre optique de réseaux de communications à l'aide de l'architecture OTIS (Optical Transpose Interconnection System), proposé dans [MMHE93]. Nous proposons une modélisation de ces réseaux par les graphes H(p,q,d) que nous cherchons ensuite à caractériser. Nous étudions en particulier les isomorphismes entre ces graphes et des graphes connus (de Bruijn, Kautz et autres graphes à alphabet). Nous développons une famille de graphes à alphabet contenant de nombreux graphes isomorphes au de Bruijn, que nous utilisons pour obtenir une implantation optimale, au sens de la minimisation du nombre de lentilles, du de Bruijn avec OTIS. Nous étudions aussi une famille de réseaux modélisés par des hypergraphes orientés, appelées stack-Kautz, pour laquelle nous donnons un algorithme de routage et des protocoles de contrôles.
Dans un deuxième temps, nous nous intéressons au problème de la sécurisation par protection dans les réseaux WDM, qui consiste à utiliser des ressources prédéterminées et dédiées pour assurer la continuité du trafic lors de la rupture d'un faisceau de fibres dans le réseau. Nous décrivons de nombreuses stratégies de protection de l'instance et du réseau. Nous étudions plus particulièrement la protection par sous-réseaux qui consiste au partage de ressources de protection par un ensemble de requêtes formant un sous-réseau particulier (circuit). Nous donnons une solution optimale au problème de la protection par sous-réseaux dans le cas où le réseau est un cycle et les requêtes représentent un échange total.
Frigui, Nejm Eddine. "Maintenance automatique du réseau programmable d'accès optique de très haut débit". Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2019. http://www.theses.fr/2019IMTA0127/document.
Pełny tekst źródłaPassive Optical Network (PON) representing one of the most attractive FTTH access network solutions, have been widely deployed for several years thanks to their ability to offer high speed services. However, due to the dynamicity of users traffic patterns, PONs need to rely on an efficient upstream bandwidth allocation mechanism. This mechanism is currently limited by the static nature of Service Level Agreement (SLA) parameters which can lead to an unoptimized bandwidth allocation in the network. The objective of this thesis is to propose a new management architecture for optimizing the upstream bandwidth allocation in PON while acting only on manageable parameters to allow the involvement of self-decision elements into the network. To achieve this, classification techniques based on machine learning approaches are used to analyze the behavior of PON users and to specify their upstream data transmission tendency. A dynamic adjustment of some SLA parameters is then performed to maximize the overall customers’ satisfaction with the network
Soulard, Rémi. "Réseaux d’indice et réseaux de gain dans les milieux lasers solides dopés Nd3+ ou Yb3+ - Utilisation pour le mélange à deux ondes et les cavités laser auto-adaptatives". Caen, 2011. http://www.theses.fr/2011CAEN2008.
Pełny tekst źródłaWave mixing in an inverted solid state laser material enables to record a population hologram that is both a gain and a refractive index hologram. This work first presents a detailed study of the electronic refractive index change that is due to a polarizability change of the ions when they are brought from the ground state to the excited state. A part of the effect comes from the presence of intense UV bands, an effect that is purely dispersive at the wavelength of the laser transition. We evaluated the non resonant polarisability changes of Nd3+ and Yb3+ ions in the main laser materials and we have studied the nature of the optical transitions at the origin of the observed refractive index variations. We then used these results to predict the potential of the laser materials in a non-degenerate two-wave mixing process for wavelengths in the vicinity of the laser transition. This model has been experimentally validated in a Nd3+:YAG crystal fiber. The study of the energy transfer from one beam to another is of great interest for applications such as phasing of N fiber lasers and self- adaptive interferometry. In addition, a diode-pumped self-adaptive laser resonator was realised and we obtained high energy per pulse. This laser gave rise to efficiencies that are quite comparable with those of conventional lasers with additional advantages such as good beam quality, single-frequency operation and self-triggering of the pulse
Bin, Ngah Lufti Arif. "Synchronisation toute optique d’un réseau de communication quantique". Thesis, Nice, 2015. http://www.theses.fr/2015NICE4141/document.
Pełny tekst źródłaThis manuscript reports the development of fundamental resources for long distance quantum communication based on fibre telecom technology and non-linear optical waveguides. After a general introduction on quantum communication, the thesis is structured along three parts. The first part illustrates the development of two photonic polarization entanglement sources suitable for quantum networking. Both sources generate paired photons at telecom wavelength via spontaneous parametric down conversion (SPDC) in periodically poled lithium niobate waveguides (PPLN/W). They rely on type-II and type 0 phase matching, respectively. In the second part, two high quality heralded single photon sources are highlighted. The first one relies on on-chip generation and spatial multiplexing of heralded single photons towards achieving higher bit rates. The second one takes advantage of passive temporal multiplexing of a single SPDC process. Finally, an all-optical approach towards efficient and accurate synchronization of remote entangled photon pair sources within quantum relay architecture over long distances is presented. This particular synchronization technique highlights the use of ultra-fast picosecond pulsed telecom fiber laser, operating at 2.5 GHz repetition rate, acting as a master optical clock, enabling to accurately synchronize the emission of photon pairs in the telecom C-band of wavelengths at two remote locations. This innovative approach is applied for synchronizing two remote PLLN/W based sources operated at 2.5 GHz, and preliminary results on two-photon interference obtained with single photons coming from each source are shown and discussed
Fedrici, Bruno. "Solutions évolutives pour les réseaux de communication quantique". Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4117/document.
Pełny tekst źródłaThis thesis presents solutions to the challenges of developing quantum communication networks. Two powerful experimental devices have been set up relying only on standard telecom and integrated optical components. The first device corresponds to an all-optical synchronization scheme allowing, with an unprecedented accuracy, quantum key distribution at a high rate over long distances. The experimental scheme relies on two independent entangled photon pair sources that have to be synchronized in their emission time. Our approach is based on using a 2.5 GHz picosecond telecom laser as a master clock to efficiently synchronize the different sources. We demonstrate the synchronization for an effective distance of 100 km between sources. With our second device, we perform a squeezing experiment at telecom wavelengths and this for the first time in a fully guided-wave approach. Squeezed light being a fundamental resource for several quantum information protocols, developing plug-and-play experimental devices that are compatible with already existing telecom fiber networks is of first interest in the perspective of future quantum networks. Finally, we propose a quantum description of timing jitter effects in 0N/0FF detectors. Despite the importance of detection systems in emerging photonic quantum technologies, no quantum description of their timing jitter effects has been proposed so far
Présent, Dominique. "Architecture d'interconnexion de cartes de commutation ATM par bus optique". Versailles-St Quentin en Yvelines, 1996. http://www.theses.fr/1996VERS0006.
Pełny tekst źródłaHan, Bing. "Réseaux de transport optique flexibles : apport de la combinaison des domaines temporel et spectral pour adapter la granularité des ressources optiques aux besoins de l'opérateur". Electronic Thesis or Diss., Paris, ENST, 2018. http://www.theses.fr/2018ENST0018.
Pełny tekst źródłaThe ever increasing traffic demand is a big challenge for the operators to increase the network capacity while lowering CAPEX and OPEX. To address these challenges, it is expected to increase flexibility of the network resources allocation while realizing directly the IP traffic routing in the optical layer. In this background, the “TIme and Spectral optical Aggregation (TISA)” approach has thus been proposed to allow a purely optical aggregation with the finest possible granularity thanks to the combination of temporal and spectral domains. The main objective of this thesis was to realize a proof of concept of the TISA concept to demonstrate experimentally the feasibility of the TISA solution. To accomplish this objective, we have designed and realized a multi-band OFDM optical burst transmitter with a narrow linewidth fast tunable laser. This laser has been implemented by combining external cavity lasers with semiconductor optical amplifier based optical gates. The transmitter is able to generate OFDM bursts in both DP-QPSK and DP-16QAM modulation formats while introducing a small penalty compared to the continuous flows configuration. We have performed the transmission of these bursts through the TISA network and have measured the bit error rates, which show less than 1 dB penalty for both modulation formats. Our results clearly show the feasibility of the TISA solution and demonstrate the ability to perform a purely optical aggregation/disaggregation and transparent routing while offering a sub-wavelength granularity in both time and spectral domains at the optical layer level
Baraketi, Sami. "Ingénierie des réseaux optiques SDH et WDM et étude multicouche IP/MPLS sur OTN sur DWDM". Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30013/document.
Pełny tekst źródłaOptical transport networks currently constitute base infrastructures for modern day telecommunications systems. Given the huge investments required for deploying these networks, and in particular concerning equipment costs (fiber optics, cards, transponders, etc.), routing optimization and resource allocation are indispensable issues for mastering the operational expenditures (OPEX). In this context, the work conducted in this thesis handle a set of resource allocation problems which arise while planning not only optical SDH (Synchronous Digital Hierarchy) and WDM (Wavelength Division Multiplexing) networks, but also multilayer ones based on an optical transport layer. First, the circuit routing problem in SDH networks is tackled with the main objective of minimizing the bandwidth fragmentation. This problem is formulated as an Integer Linear Program (ILP) integrating a set of realistic routing, transmission and cross-connect constraints and using granular resource costs. An exact algorithm and two heuristics are proposed to solve this problem. The rerouting problem of SDH circuits, which faces operators when it becomes absolutely necessary to reduce the bandwidth fragmentation in the network, is also addressed. For real instances of the studied problems, it is shown that the proposed methods provide considerable economic gains. Second, two planning problems for WDM network optimization is tackled. The first problem is that of the logical network design, or in other words that concerned with the definition of lightpaths to route a set of traffic demands with a minimum transponder cost. The second problem is related to the routing and the wavelength assignment: how to route the previously defined lightpaths so as to minimize the total number of assigned wavelengths while respecting a set of technological constraints? These two problems are formulated as Integer Linear Programs (ILPs) and are solved using efficient heuristics, based on a successive approximation for the first problem and a decomposition approach for the second one. Here again, experimental results show that the proposed methods allow obtaining good quality approximations for large scale instances. Finally, resource allocation in new generation multilayer networks, that is IP/MPLS over OTN (Optical Transport Network) over DWDM (Dense WDM), is addressed. In this case, the question that most of the operators seek to answer is how to route layer 3 traffic demands while optimizing resource allocation, not only in the IP/MPLS layer, but also in the underlying OTN and DWDM layers. For this purpose, a new multilayer optimization model is proposed. It takes into account a hierarchy of material constraints and defines a tradeoff between the resource costs in the three network layers. The set of proposed optimization algorithms have been integrated into the network planning and optimization environment NEST of QoS Design, which is used by major operators to plan their network
Es-Saidi, Soukaina. "Optimisation de la réponse optique de réseaux diffractifs métalliques appliqués à la sécurité des documents". Thesis, Troyes, 2020. http://www.theses.fr/2020TROY0016.
Pełny tekst źródłaSecurity holograms based on sub-wavelength gratings (SWGs) are increasingly used not only to protect sensitive documents, but also to combat against the reprographic technologies used in counterfeiting.The aim of the present work is to design optical security devices to produce visual and chromatic effects, based on the generation of structural colors, easily recognizable but difficult to counterfeit and compatible with high-tech foil production. To this end, we study the optical response of one and two-dimensional asymmetric SWGs fabricated by laser interferometric lithography and scaled up to larger scales on polymer film using roll-to-roll replication processes. The in-depth physical analysis of the resonance mechanisms generated by metallic and hybrid metal-dielectric SWGs allows to understand and tailor their chromatic response. We also demonstrate that hybrid SWGs open new design perspectives and enhance the quality of the perceived colors. The research evidence presented in this contribution clearly shows that the use of modern optimization tools, prior to fabrication, provides an efficient way to tailor and to optimize the resonant response of diffraction gratings. We demonstrate that the multi-objective approach outperforms single-objective strategies and opens the possibility of increasing the complexity of the diffractive structures used for color reproduction. We emphasize that Artificial Intelligence tools constitute an efficient alternative to the traditional time-consuming electromagnetic methods
Blau, Gerd. "Doubleurs de fréquences en optique intégrée utilisant des polymères et des nano-réseaux de diffraction". Grenoble INPG, 1996. http://www.theses.fr/1996INPG0110.
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