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Nanni, Jacopo. "High performance, low cost and low consumption Radio over fiber Systems for diversified communications applications". Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1162/document.
Pełny tekst źródłaThis dissertation aims to analyze the possibility of improving in terms of cost and consumption the future Radio-over-Fiber (RoF) systems in different telecommunication scenarios, such as current and next generation of cellular networks and in other applications such as Radio Astronomy. The RoF system studied is hence composed of a Vertical Cavity Surface Emitting Laser (VCSEL) operating at 850 nm, standard single mode fiber (SSMF) and SiGe Heterojunction Phototransistor (HPT), adopting the technique called Intensity Modulation{Direct Detection which is nowadays the cheapest and simplest architecture for RoF. This dissertation describes in detail the multimode propagation within the SSMF (designed to operate only at 1310 nm and 1550 nm) which is present at 850 nm. Through a developed mathematical model, the two-modes propagation is described and the main phenomena involved are analyzed. In particular, the model focus on intermodal dispersion and modal noise which are considered the two main contributions of performance detrimental. The model developed is able to identify the main parameters which contribute to enhance the detrimental effects produced by intermodal dispersion and modal noise both in frequency and time domain. Starting from the model, possible techniques to improve the performances are then proposed. In particular, a pre-filtering technique is realized in order to avoid the excitation of the second order mode, allowing a quasi-single-modepropagation within the SSMF. The technique is theoretically and experimentally validated either for single radio frequency sinusoidal transmission either for bandpass signal transmission centered in radio frequency band. In particular it is demonstrated experimentally the possibility of increasing the modulationbandwidth of the RoF system, reducing at the same time the fluctuations of power and gain. Furthermore, the technique is validated in a real LTE transmission system, making the RoF technology proposed able to transmit 256-QAM LTE signal of 20 MHz bandwidth, confirming the possibility of using this technology to decrease the overall cost and consumption of the network. Further work hasbeen done on the mathematical model. In particular the two modes propagation is exploited reversely in order to characterize the chirp parameter of the VCSEL employed. Finally, the problem of coupling between fiber and opto-electronic devices is also discussed and investigated, in order to enhance theperformances while keeping low the cost. The possibility of utilizing a collective and passive ploymerbased structure for coupling the optical fiber with small area photodetectors and VCSEL is presented, showing important improvements on coupling efficiency and tolerance to misalignment
Lefebvre, Kim. "Technique de réutilisation de longueur d'onde optique dans des applications RoF basée sur les RSOA pour des communications bidirectionnelles OOK et OFDM". Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/37718.
Pełny tekst źródłaKhayatzadeh, Ramin. "Convergence des technologies optique et radio pour la génération dédiée aux communications aux fréquences supérieures à 60 GHz". Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT074/document.
Pełny tekst źródłaThis Ph.D. investigates the radio over fiber communication systems at mm-wave frequencies higher than 60 GHz. The thesis elaborates on three crucial issues in these systems including:phase noise measurement of unstable optically generated mm-wave signals, elimination ofphase noise impact on performance of radio over fiber systems using non-coherent down conversion technique, and studying the amplitude noise impacts on performance of system based on these detectors. In the first part of this work, a new digital phase noise measurement technique is presented which is able to extract the phase noise of any unstable mm-waveoptically generated signal. This technique is able to measure the phase noise for a widerange of offset frequencies from close-in phase noise to far noise floor by adapting frequency resolution of measurement and without considering small angle approximation. In the second part, we present a radio over fiber system at mm-wave frequency based on non-coherent electrical frequency down conversion stage using an envelope detector which is robust against phase and frequency fluctuations of the optically generated carrier signal. Finally, a the oreticaland experimental study of amplitude noise impact on performance of radio over fiber systemsbased on non-coherent receivers is presented. In this study, a simulation technique based ontheory is developed which is able to determine, among different optical and electrical noise, the one which has the dominant effect on EVM results. This simulation technique is based onobserving the EVM evolution versus received optical power
De, Valicourt Guilhem. "Conception, fabrication, et évaluation de modulateurs déportés pour les réseaux d'accès et radio sur fibre". Phd thesis, Télécom ParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00677397.
Pełny tekst źródłaBenzazaa, Mostafa. "Etude d'architectures de systèmes de transmission de signaux ULB RF et millimétriques avec lien optique : application à la Radio-sur-Fibre". Paris 6, 2011. http://www.theses.fr/2011PA066218.
Pełny tekst źródłaAudo, Frédéric. "Opto-alimentation et transmission de données par fibre optique pour les observatoires de fond de mer". Phd thesis, Université de Bretagne occidentale - Brest, 2012. http://tel.archives-ouvertes.fr/tel-00782502.
Pełny tekst źródłaGatti, Sylvain. "Inscription laser UV pulsé sur nouveau matériau hybride pour codeurs optiques intégrés". Phd thesis, Montpellier 2, 2007. http://www.theses.fr/2007MON20238.
Pełny tekst źródłaLa technologie sol-gel a déjà démontré son potentiel. Un nouveau matériau sol-gel hybride à polymérisation cationique de type Epoxy a été développé dans le but de la simplification de la synthèse et de l'amélioration des performances en particulier l'adhérence.
Ce travail a pour objectif le développement d'un banc d'écriture laser UV dans une couche Epoxy et l'établissement du protocole de fabrication associé. Ce procédé de polymérisation locale est une alternative prometteuse aux techniques lithographiques par masque.
Ce nouveau banc utilise un laser pulsé travaillant à faible longueur d'onde pour une meilleure résolution et une meilleure polymérisation.
Ce travail a montré la faisabilité de circuits complexes de type multiplexeurs WDM avec un procédé d'inscription à faible coût. Nous avons réalisé les premiers prototypes de circuits dédiés à la sélection multiple de longueurs d'onde pour le (dé)codage du CDMA optique spectral.
Gatti, Sylvain. "Inscription laser UV pulsé sur nouveau matériau hybride pour codeurs optiques intégrés". Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2007. http://tel.archives-ouvertes.fr/tel-00258256.
Pełny tekst źródłaLa technologie sol-gel a déjà démontré son potentiel. Un nouveau matériau sol-gel hybride à polymérisation cationique de type Epoxy a été développé dans le but de la simplification de la synthèse et de l'amélioration des performances en particulier l'adhérence.
Ce travail a pour objectif le développement d'un banc d'écriture laser UV dans une couche Epoxy et l'établissement du protocole de fabrication associé. Ce procédé de polymérisation locale est une alternative prometteuse aux techniques lithographiques par masque.
Ce nouveau banc utilise un laser pulsé travaillant à faible longueur d'onde pour une meilleure résolution et une meilleure polymérisation.
Ce travail a montré la faisabilité de circuits complexes de type multiplexeurs WDM avec un procédé d'inscription à faible coût. Nous avons réalisé les premiers prototypes de circuits dédiés à la sélection multiple de longueurs d'onde pour le (dé)codage du CDMA optique spectral.
Liu, Jingtian. "Shaping Strategies to Embrace Nonlinear Effects in Optical Fiber Communications". Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAT007.
Pełny tekst źródłaThe main impediment in long-distance communications is nonlinear interference (NLI), stemming from nonlinear effects in optical fibers. While Digital signal processing algorithms offer partial mitigation, the inherent nonlinear nature of the fiber, coupled with predominant dispersion effects, continues to challenge the increase of transmission throughputs. Addressing nonlinearity at the information source through signal modulation technology is at the heart of our research. Traditional modulation schemes, as spectral efficiency climbs, such as QAM, become increasingly susceptible to NLI while their Mean Squared Euclidean Distance (MSED) diminishes. While multi-dimensional (MD) modulation yields improved linear and partial nonlinear gains, it has not yet demonstrated tangible benefits. On the other hand, the emergence of probabilistic constellation shaping (PCS), preferred for its enhanced linear gain and compatibility with conventional modulation hardware and software, introduces additional NLI. Consequently, the design of nonlinear-tolerant PCS is emerging as a pivotal research direction. Our thesis begins with a novel MD modulation for uniformly distributed signals. Then, we propose a novel approach combining MD with PCS to examine performance variations. Delving into PCS, we investigate the enumerative sphere shaping distribution matcher (DM), initially from an MD stance, and design a DM optimized for nonlinear tolerance over shorter distances. Subsequently, we introduce a new NLI measurement technique, accounting for dispersion effects. Integrating this with the sequence selection framework of PCS, we achieve successful long-distance transmission with notable nonlinear gains
Shahkarami, Abtin. "Complexity reduction over bi-RNN-based Kerr nonlinearity equalization in dual-polarization fiber-optic communications via a CRNN-based approach". Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAT034.
Pełny tekst źródłaThe impairments arising from the Kerr nonlinearity in optical fibers limit the achievable information rates in fiber-optic communication. Unlike linear effects, such as chromatic dispersion and polarization-mode dispersion, which can be compensated via relatively simple linear equalization at the receiver, the computational complexity of the conventional nonlinearity mitigation techniques, such as the digital backpropagation, can be substantial. Neural networks have recently attracted attention, in this context, for low-complexity nonlinearity mitigation in fiber-optic communications. This Ph.D. dissertation deals with investigating the recurrent neural networks to efficiently compensate for the nonlinear channel impairments in dual-polarization long-haul fiber-optic transmission. We present a hybrid convolutional recurrent neural network (CRNN) architecture, comprising a convolutional neural network (CNN) -based encoder followed by a recurrent layer working in tandem. The CNN-based encoder represents the shortterm channel memory arising from the chromatic dispersion efficiently, while transitioning the signal to a latent space with fewer relevant features. The subsequent recurrent layer is implemented in the form of a unidirectional vanilla RNN, responsible for capturing the long-range interactions neglected by the CNN encoder. We demonstrate that the proposed CRNN achieves the performance of the state-of-theart equalizers in optical fiber communication, with significantly lower computational complexity depending on the system model. Finally, the performance complexity trade-off is established for a number of models, including multi-layer fully-connected neural networks, CNNs, bidirectional recurrent neural networks, bidirectional long short-term memory (bi-LSTM), bidirectional gated recurrent units, convolutional bi-LSTM models, and the suggested hybrid model
Araujo, Viana Carlos. "Développement technologique et intégration système de VCSEL et HPT SiGe pour des applications radio-sur-fibre 60 GHz bas coût". Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1003/document.
Pełny tekst źródłaWireless communication technologies have become one of the most popular and indispensable part of people's lives in the recent years, offering mobility and services never before available from mobile communication until local network communication. This work is based on the frame of the French ORIGIN project and intended to explore the Home Area Network using the most recent Wi-Fi standard at 60 GHz with the goal to present a solution for the upcoming days where MultiGbit/s wireless communication will be required. The ORIGIN solution is characterized by the complementary action of two technologies: 60 GHz Wireless communication and Radio-over-Fiber (RoF) infrastructure. The project pretends to propose a real prototype based on RoF transducers and a Multipoint-to-Multipoint architecture to cover the entire house. This thesis covers from the single optoelectronic chip devices until the system implementation and the final demonstrator. The light source and the photodetector choice were very important since it dictated the RoF transducer architecture. Our choice was on 850 nm multimode devices (GaAs VCSEL and SiGe HPT) which allow relaxed constraints on the optical packaging and, therefore, low cost solutions. In terms of performances those devices are limited in a few tens of Gigahertz of bandwidth which was the reason for the intermediate frequency (IF) architecture. This thesis work addressed the electrical and optical interconnection of the optoelectronic chip devices. It explored the integration of hybrid amplification stages and passive networks within optoelectronic receivers and emitters. The optical packaging issues were addressed through a conventional coupling technique using a ball lens first. The die device performances were evaluated and compared with a packaged module in terms of frequency response, noise and nonlinearities. Since performances are usually measured as link performances we proposed a definition of the Opto-microwave figures of merit, such as Opto-microwave gain, noise, nonlinearities and EVM. They are presented and integrated into behavioral models, allowing both the individual performances extraction and system design. The integration of the RoF module in the system is the final part of this thesis. The performances were measured and simulated at each integration step. The final demonstrator based on the multipoint-to-multipoint architecture was implemented using an optoelectronic central node for the signal repartition and the Green Box for signal controlling. Real-time bidirectional transmission between two commercial WirelessHD devices at ~3 Gbit/s was validated. In a final section directions to improve VCSEL and SiGe HPT are explored. 25 GHz analogue VCSELs are explored with a focus on their dimensions, improved access and the potential of a suited matching approach. A novel collective and passive optical coupling technology is also proposed for both VCSEL and top illuminated detectors that couple smaller and faster devices
Guillory, Joffray. "Radio over Fiber (RoF) for the future home area networks". Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1083/document.
Pełny tekst źródłaThe evolution of the Home Area Network (HAN) is lead by the proliferation of connected devices inside the home and the deployment of high broadband access network which now allows the delivery of services that can exceed 1Gbit/s. To ensure efficient in-house exchanges, the HAN has to move rapidly toward multi-Gigabit/s connections, in particular the wireless connectivity generally preferred by the customers. Current wireless systems have limited capacities, but new radio standards delivering data-rates up to 7Gbit/s are emerging. Nevertheless, as they address the unlicensed millimeter-wave band, from 57 to 66 GHz, their radio coverage is limited to a single room. Indeed, at such frequencies, the free-space losses are high and the waves do not cross the walls. This thesis proposes to solve this problem by means of the Radio over Fiber (RoF) technology. This consists in capturing the 60GHz radio signals emitted in one room, converting them into optical signals for transmission through optical fibers, and reemitting them in another room. Thus, several RoF transducers will be installed in the home and interconnected by a suitable optical infrastructure to create systems acting at the same time as repeaters and as distribution systems. From the viewpoint of the HAN market, such systems will be competitive only if they are low cost. As a consequence, this work focuses on direct modulation with direct detection (IM-DD) at Intermediate Frequency (IF). In other words, the 60GHz signal is down-converted at a lower frequency around 5GHz before the laser modulation and up-converted to 60GHz after the photodetection. Concerning the optical fiber, silica multimode fiber (MMF) is privileged as it allows the use of low cost and largely available optoelectronic devices working at 850nm.The thesis proposes different RoF architectures, from point-to-point interconnecting two rooms to multipoint-to-multipoint acting as logical buses. After an analog characterization of the optoelectronic components, the RoF link and the domestic cable, these architectures are designed, built and characterized step by step using OFDM modulation according to existing wireless 60GHz standards. Real-time transmissions between commercial devices have also been performed to validate these architectures. Moreover, advanced RoF infrastructures are proposed. First, the RoF systems can be easily improved if the access to their optical media is managed by the radio MAC layer. This approach is therefore studied showing its feasibility. Secondly, an optical system, seen by users as a premium product, has to support the legacy home services commonly used as well as the new ones that could emerge in the future. Thus, innovative multiservice and multiformat infrastructures conveying on a unique optical cable wired IP data, broadcast terrestrial or satellite television, the 60GHz wireless connectivity, and specific formats as HDMI signals are proposed and tested
Rzaigui, Habeb. "Systèmes hybrides opto/sans fil pour les réseaux multi-gigabits aux fréquences millimétriques". Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAT014/document.
Pełny tekst źródłaThis thesis focuses on the radio-over-fiber (RoF) communication systems at millimeter frequencies in the frequency range 57-66 GHz and optical generation of a signal at millimeter-wave frequency band. The technique used is based on mode-locked laser diodes. The diodes employed in this work are in quantum dots (or quantum dashes) technology. In this thesis, several studies were conducted: the first relates the ability of integration these types of lasers in the RoF communication systems under direct or external modulation. The second study was devoted to propagation effects. An original technique was implemented to reduce the sensitivity to chromatic dispersion in an optical fiber. A study of the reduction of phase noise mode-locked lasers based on the observation of the reaction effect and against the external optical injection was presented
Boldyreva, Ekaterina. "Mesures réparties par réflectométrie fréquentielle sur fibre optique". Phd thesis, Toulouse, INPT, 2016. http://oatao.univ-toulouse.fr/18709/1/Boldyreva_Ekaterina.pdf.
Pełny tekst źródłaVallée, Jean-Michel. "Source laser accordable jumelant photonique sur silicium et fibre optique". Master's thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/69037.
Pełny tekst źródłaThis master's thesis is on the design of a hybrid laser combining optical bers and the technology of silicon photonics. The main objective is to achieve a laser with great control and exibility over its emission parameters and with good performances for the eld of optical telecommunications. Until now, several approaches leading to laser integration on the silicon photonics have been demonstrated. Unlike integration approaches which aim to produce the most compact source possible, the chosen approach aims to produce a high-performance laser which exploits both the optical amplication performance of the doped bers as well as the potential of light processing and precision that oers the silicon photonic platform. The operating principle as well as the theoretical models of dierent optical devices accessible thanks to the silicon photonics are presented in detail. These devices allowing optical connement at the 100-nanometer scale level as well as the manipulation of light are key elements in the design of optical lters for the laser cavity. The performances of a Vernier lter on silicon are analyzed by means of numerical simulations. Two types of hybrid lasers are presented in this document. The rst is a multimode laser allowing a selection of the spectral spacing between its modes. The second type of laser is a single-mode laser operating at 2000 nm and tunable over a range of 100 nm. In the rst case, the amplication medium of the cavity is composed of an optical ber doped with erbium while in the second, it is a ber doped with thulium.
Fortin, Guillaume. "Circuits en AsGa pour la transmission de données sur fibre optique". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ33131.pdf.
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 źródłaNicati, Pierre-Alain. "Capteur de courant à fibre optique basé sur un interféromètre de Sagnac /". [S.l.] : [s.n.], 1991. http://library.epfl.ch/theses/?display=detail&nr=976.
Pełny tekst źródłaThon-Adjalin, Carolle. "Étude d'un système de transmission sur fibre optique plastique à saut d'indice". Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28166/28166.pdf.
Pełny tekst źródłaTEMMAR, ABDELKADER. "Photodiode metal-semiconducteur-metal (msm) alinas/gainas pour transmission sur fibre optique". Paris 6, 1992. http://www.theses.fr/1992PA066341.
Pełny tekst źródłaNorcia-Molin, Stéphanie. "Augmentation de la profondeur de modulation de signaux hyperfréquence sur porteuse optique par effets non linéaires dans les fibres". Paris 11, 2004. http://www.theses.fr/2004PA112118.
Pełny tekst źródłaOptical fibres tend to replace coaxial cables in many systems of transport and processing of microwave signals. In particular, future generations of radar systems will be equipped with opto-electronic links thus using with profit the advantages of optical fibres (weak weight, size, cost and large bandwidth). In these future radar systems, the linear transposition of microwave information on optical carrier with traditional integrated intensity modulators (such as mach-zehnder) is amplitude-limited. The resulting signal is thus composed of a weak modulated part containing the microwave information and of a strong continuous component which can saturate some of the opto-electronic link components. In this work we studied two non-linear processes in optical fibres allowing selective and dynamic attenuation of the optical carrier only, without any attenuation of the microwave signal. This means an increase of the signal contrast, that is to say an increase of its modulation depth. The first studied effect is stimulated brillouin scattering in optical fibres (including in photonic crystal fibres). The second studied effect is two wave mixing by gain saturation in an amplifying optical fibre. The feasibility of modulation depth increase of the microwave signal by these two techniques respectively has been proven. An increase of the modulation depth of the signal by a factor 10 000 has been demonstrated
Fernandez, Fernandez Alberto. "Photonics for nuclear environments from radiation effects to applications in sensing and data-communication". Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210843.
Pełny tekst źródłaYATAGHENE, AREZKI. "Surveillance de la temperature par reflectometrie optique a correlation sur fibre dopee holmium". Paris, CNAM, 1994. http://www.theses.fr/1994CNAM0173.
Pełny tekst źródłaVergnol, Eric. "Convertisseur millimétrique optique à bande latérale unique pour le transport radio sur fibre". Brest, 1999. http://www.theses.fr/1999BRES2032.
Pełny tekst źródłaRavaille, Alexia. "Gyromètre optique basé sur une cavité résonante passive en fibre à cœur creux". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS411/document.
Pełny tekst źródłaIn this manuscript, we report the theoretical and experimental developments at TRT, TAV and LAC, aiming the realization of a hollow-core passive resonant fiber optical gyroscope that can achieve navigation grade performances. We mathematically describe the Sagnac effect, which is a relativistic effect used to optically probe mechanical rotations. Then, we detail the state of the art in passive resonant fiber optical gyroscope development. We identify their limitations, and explain why the hollow core fiber seems to be the best solution to cope with the actual limitations of such gyroscopes. We then focus on two different types of hollow core fibers: Kagome and photonic bandgap. We evaluate their performances in terms of transmission, polarization holding and backscattering. We describe the first measurement of a lock in region in a hollow core fiber passive optical gyroscope, i.e the range of rotation rates that cannot be measured because of backscattering. A mathematical model is propounded to link the lock in to the backscattering of the cavity. We then discuss the experimental protocol that we implemented to circumvent this limitation. Finally, we characterize the performances of our gyroscope based on these features
Bouhamri, Zine-Abidine. "Transmission multi-standards sur lien optique bas-coût". Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-00957588.
Pełny tekst źródłaNicole, Jean-François. "Étude sur les capteurs à fibre optique pour l'instrumentation de structures de génie civil". Mémoire, Université de Sherbrooke, 2000. http://savoirs.usherbrooke.ca/handle/11143/1209.
Pełny tekst źródłaHamel, André. "Contribution à l'étude de la modulation de cohérence pour les transmissions sur fibre optique". Besançon, 1991. http://www.theses.fr/1991BESA2052.
Pełny tekst źródłaThe central theme of this thesis is coherence modulation and more particularly its application to fiber optic transmission. The principle of this technique is based on the coding of the signal by modulation of a delay introduced between the fields emitted by an optical source operating continuously. This modulation is obtained by electro-optical means. After a presentation of the main characteristics of coherence modulation, a fully fibered monomode link is tested at 1. 3 µm in analog transmission and in digital transmission at 140 Mbits/s. A suitable optical receiver is studied and the detection thresholds are specified for higher data rates. Then, the thesis approaches the serial and parallel architecture of the modulators: we deduce the level of the received signal as well as the incidences on the hierarchy of the delays. […] A particular application of coherence modulation is discussed in the case of interactive links. By combining this technique with an external intensity modulation, it is possible to ensure the simultaneous transmission of signals of the same bandwidth with a single optical source on a single fiber: this application is particularly interesting for telecommunications because it avoids the installation of an optical source at the user
Salhi, Miyassa. "Étude d’un système de surveillance de structure par fibre optique reposant sur l’effet Brillouin". Thesis, Paris Est, 2020. http://www.theses.fr/2020PESC2031.
Pełny tekst źródłaThe use of distributed sensors fiber optic delivering information in each point of the fiber is an important tool for large-scale structures surveillance strategies in civil engineering. The spontaneous Brillouin scattering phenomenon (or stimulated) in the field of sensors optical fiber is subject to strong scientific inquiry since the 1990s. The proposed industrial solutions are based on the spectral analysis of the Stokes wavelength backscattered along the length of the fiber. Thus, a B-OTDR device (Brillouin Optical Time-Domain Reflectometer) can perform a measurement of the shift of the Brillouin frequency (of the order of 11GHz around 1.55 µm) with a metric spatial resolution and sensitivity of the strain measurements and temperature respectively of about 10 µm/m and 0.5 °C, but at a high cost (about 100k€) which limits their use. This thesis is oriented towards the study of a monitoring system based on the use of a bi-frequency bi-polarization source, which would make it possible to remedy the drawbacks of conventional systems and have equivalent performances with state of the art solutions
Nicole, Jean-François. "Étude sur les capteurs à fibre optique pour l'instrumentation de structures de génie civil". Sherbrooke : Université de Sherbrooke, 2000.
Znajdź pełny tekst źródłaRejeaunier, Xavier. "Etude et réalisation d'un filtre accordable en longueur d'onde intégré sur LiNbO3 : application à un laser à fibre dopée erbium accordable". Besançon, 2003. http://www.theses.fr/2003BESA2057.
Pełny tekst źródłaGouali, Mohamed El Hadi. "Modélisation et optimisation d'une ligne de transmission bidirectionnelle, multiplexée en longueurs d'ondes sur fibre optique". Paris 11, 1985. http://www.theses.fr/1985PA112343.
Pełny tekst źródłaBulot, Patrick. "Étude et réalisation sur tour de fibrage de capteurs à fibre optique pour environnements extrêmes". Thesis, Lille, 2019. http://www.theses.fr/2019LIL1R018.
Pełny tekst źródłaThe Ph.D. work focuses on the realisation of optical fibre sensors protected by a high-temperature resistant coating. The aim application temperature is above 350 °C. One part of the work is done on a fibre draw tower to improve the mechanical reliability of these compact sensors.The first part of the presented work focuses on the microstructural study of point-by-point fibre Bragg gratings. These gratings are inscribed in the optical fibre core with a femtosecond laser. The analysis by transmission electronic microscopy shows germanium chemical gradient near the periodic modifications. This gradient could partially explain the spectral evolutions of these sensors at 1000 °C.The second study shows the performances of zirconia nanoparticle-doped optical fibres for distributed sensing at 800 °C by Optical Frequency Domain Reflectometry. These fibres have a better stability of temperature measurement than conventional fibres for optical telecommunication.The third study is related to the mechanical protection of optical fibres by a high-temperature resistant coating. For the first time, a silicone coating with fillers is studied like a coating for optical fibre. The coating is applied on fibre Bragg gratings by dip-coating to study the behaviour of the coating on the fibre up to 470 °C. Then the coating is applied on an optical fibre by using a fibre draw tower. A 100 meter-length fibre is protected with a thickness of around 13 µm
Zaldivar-Huerta, Ignacio. "Transmission sur une sous porteuse micro-onde dans une fibre dispersive à l'aide d'une diode laser multimode". Besançon, 2001. http://www.theses.fr/2001BESA2023.
Pełny tekst źródłaWanlin, Guilaine. "Photodiodes pin gaa1inas ultra-rapides et sensibles a eclairage lateral pour transmissions a haut debit sur fibre optique et distribution optique-radio". Paris 7, 1996. http://www.theses.fr/1996PA077359.
Pełny tekst źródłaGIBASSIER, CHARLES. "Nouvelles solutions pour la distribution des services de telecommunications sur fibre optique dans le reseau local". Rennes 1, 1994. http://www.theses.fr/1994REN10066.
Pełny tekst źródłaMeilland, Philip. "Construction d'un amperemetre a grande bande passante base sur l'effet faraday dans une fibre optique unimodale". Limoges, 1988. http://www.theses.fr/1988LIMO0031.
Pełny tekst źródłaMeilland, Philip. "Construction d'un ampèremètre à grande bande passante basé sur l'effet Faraday dans une fibre optique unimodale". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376161051.
Pełny tekst źródłaHauden, Jérôme. "Transmissions bidirectionnelles sur fibre optique indépendantes de la polarisation : étude et réalisation de multiplexeurs-démultiplexeurs de cohérence intégrés sur LiNbO3". Université de Besançon, 1995. http://www.theses.fr/1995BESA2028.
Pełny tekst źródłaIn the field of optical telecommunicaitons applied to local aera netwoks, coherence multiplexed techniques appear to be particular interest for realizing bidirectional transmissions. Such links, in which several counter-propagative signals are transmitted in the both direction of the same fiber, are sensitive to environmental perturbations, including random polarization rotations of guided light. This thesis feals whith the study and realization of lithium niobate (LiNbO3) integrated optical devices that exhibit the properties required to achieve a coherence multi-demultiplexing process: generation of large optical delays, electroopic modulation. It is possible to build polarization independent devices by choosing a particular crystalline orientation and applying suitable electric fields. Therefore, the problem of perturbations is overcome, improving the efficienty of single mode fiber based telecomunications
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 źródłaBudianto, Anwar. "Etudes des nouvelles solutions de connectique entre guides de lumière réalisés sur substrat silicium et fibre optique". Grenoble INPG, 1993. http://www.theses.fr/1993INPG0022.
Pełny tekst źródłaBenyahya, Kaoutar. "Mode group division multiplexing for short reach optical communications". Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S117.
Pełny tekst źródłaThe ever-growing demand of data traffic will be fuelled by revolutionary technologies such as virtual reality (VR), augmented reality (AR) and Internet of things (IoT). Therefore, optical networks should support the requirements of these services in terms of high capacity, low latency and high reliability. In fact, large scale capacity is a critical need for fiber optic communication systems deployed in local area networks as well as in datacenters. For both applications, systems relying on intensity modulation and direct detection (IMDD) are highly demanded due to their low cost and compatibility with short range applications. In this thesis, we address the need of increasing the data rates for short reach optical communication systems based on mode group division multiplexing and direct detection schemes. Firstly, we focus on increasing the capacity of already deployed standard multimode fibers in local area networks and intra-datacenters communication where the distance is shorter than 5 km. Secondly, we extend our solution to longer reach applications such as inter-datacenter interconnects. In both cases, optical link architectures, including transmitters, receivers and the optical fibers are analysed. Moreover, modulation formats adapted to IMDD systems such as single carrier 4-PAM and multicarrier DMT are compared in the context of space division multiplexing transmission. In this work we demonstrated the achievable benefit of mode group multiplexing combined with IMDD schemes. First, 5 Tb/s has been achieved over 2.2 km of conventional multimode fiber (OM2). Secondly, transmission record at the corresponding time of its realization of 14.5 Tb/s over OM2 fiber is demonstrated. Finally, 200 Gb/s over 20 km of FMF has been achieved which extend the benefit of mode group multiplexing to longer reach applications compared to LAN and intra-datacenter where the maximum distance is limited to 5 km
Kabalan, Ali. "Etude de systèmes radio sur fibre pour des applications de réseaux domestiques en bande millimétrique". Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1013/document.
Pełny tekst źródłaThe growth continually demand of higher data rates in recent decades, supported by the deployment of optical networks allowing a flow of the order of several Gbit/s naturally leads to application development interest on 60 GHz local networks. Standards such as IEEE IEEE 802.15.3c and 802.11ad for millimeter-band wireless transmission have been proposed. At such frequencies, the free space loss is very high and the radio waves do not penetrate walls. The radio over fiber links (RoF), used as optical link from one room to another and enable the distribution of high-speed signals throughout the home or throughout the building, overcoming the failure for low distance free space propagation. Access, by modeling the electrical equivalent of each component of the system considered circuits, simulation of the RoF systems enables optimization of the system in terms of transmission quality. Thus, the optical and electrical characteristics of components of RoF systems are studied and analyzed together which offers the possibility of designing integrated photonic-RF circuits. This thesis concerns the study and simulation of RoF links using electrical equivalent circuits of photonic components. This study is intended for wireless applications at 60 GHz of bandwidth for a high transmission rate. The modulation technique of direct or external intensity and direct detection is preferred at an intermediate frequency in order to ensure simplicity and low cost of the system. The radio signal is then transposed onto a carrier in the band 60 GHz. First, to validate the models developed electrical equivalent circuit, the measured characteristics of optoelectronic components are compared with simulation results. Then, the characterization study is conducted to the scale by analysis of analog parameters such as gain, noise and non-linearity. The dynamics of different RoF links can thus be determined. Transmitting OFDM complex digital signal is finally achieved by a method of digital / analog co-simulation. The transmission quality has been studied by evaluation of the magnitude of the error vector (EVM) constellations digital signals. The study is conducted and validated as a first step in accordance with the ECMA-368 standard dedicated to the centimetric band and then spread to the millimeter band from IEEE 802.15.3c standard. Finally, the channel effect in free space at 60 GHz is considered to analyze the transmission end to end
Trudel, Vincent. "Capteurs de déplacement à fibre optique à modulation d'intensité basée sur la présence de désalignements entre fibres monomodes". Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24525/24525.pdf.
Pełny tekst źródłaBourden, Sylvie. "Caractérisation par capteur optique de l'évolution spatio temporelle du dépôt formé lors de la filtration sur fibre creuse". Toulouse, INPT, 1990. http://www.theses.fr/1990INPT005G.
Pełny tekst źródłaREAU, ANNE-CECILE. "Influence de l'environnement immediat de la fibre optique sur son comportement en cable ; application au micro-module ; optimisation". Rennes 1, 1996. http://www.theses.fr/1996REN10142.
Pełny tekst źródłaBoudrioua, Nassima Dandache Abbas. "Etude et optimisation d'une chaîne de transmission numérique sur fibre optique vers une compensation électronique de la PMD /". [S.l.] : [s.n.], 2007. ftp://ftp.scd.univ-metz.fr/pub/Theses/2007/Boudrioua.Nassima.SMZ0724.pdf.
Pełny tekst źródłaRoumestan, François. "Techniques avancées de traitement du signal pour les systèmes de distribution quantique de clés sur fibre optique basés sur des variables continues". Electronic Thesis or Diss., Sorbonne université, 2022. https://theses.hal.science/tel-03880444.
Pełny tekst źródłaQuantum key distribution offers the possibility of cryptography whose security is demonstrated by the laws of quantum physics. The first commercial systems of this technology are now available. This thesis focuses on continuous variable protocols, whose practical implementation is close to modern digital transmission techniques over optical fibers. By exploiting these techniques, we realize an experimental system for high speed continuous variable quantum key distribution
Vourc'H, Eric. "Filtre optique à bande latérale unique auto-accordable pour les systèmes hybrides fibre-radio". Phd thesis, Université de Bretagne occidentale - Brest, 2002. http://tel.archives-ouvertes.fr/tel-00817878.
Pełny tekst źródłaGinestar, Stéphane. "Réalisation et caractérisation d’un laser DFB bi-mode pour applications radio sur fibre". Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10092/document.
Pełny tekst źródłaGeneration of microwave, millimetre-wave even THz signals by optical means is currently a favoured technique for a lot of system applications such as: high bit-rate wireless telecommunications, local oscillator or radar signal distribution within satellites, video signal distribution, automotive communications, THz security systems, etc… We report here the fabrication and the characterization of an ultra-compact optical source made of semiconductor material. It allows generating two optical modes that are separated by the frequency that is requested at the photodetector level. This source is composed of two DFB lasers constituting a dual-mode laser emitting in the 1.55µm wavelength range. The device has been fabricated at Alcatel-Thales III-VLab using a proprietary DFB technology and the work has been supported under the "IPHOBAC" European project. Several targets were fixed for this device: tunability of intermodal spacing up to 300GHz, optical linewidth close to the MHz as well as horizontal and vertical divergences around 10°. The first goal has been achieved by using two DFB structures with a 0.3nm difference in the grating pitch and tuning the drive current of each section. The second goal has been globally achieved by using a quantum well based active layer. A new version including quantum dot based active layer should answer positively to this target. Last objective was partially obtained by the design and the integration of a spot size converter. The divergence has been measured as 10°x17° (HxV). Concerning the vertical divergence, the target of 10° was not obtained mainly linked to the device structure and the limitations we fixed on the overall length of the device