Rozprawy doktorskie na temat „Transmissions à haut débit symbole”
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Arnould, Aymeric. "Ultra-wideband and high symbol rate transmission systems for next-generation optical fiber communications". Electronic Thesis or Diss., Institut polytechnique de Paris, 2021. http://www.theses.fr/2021IPPAS006.
Pełny tekst źródłaOptical fiber transmissions have enabled the development of the high capacity and resilient networks that form the backbone of the modern-day global telecommunication system. Whereas low-loss fibers and erbium doped fiber amplifiers (EDFA) allow wavelength division multiplexing (WDM), coherent detection enables advanced modulation and coding schemes, and digital signal processing (DSP) is used to compensate for physical propagation effects. In this thesis, we address possible solutions for the next generation coherent WDM systems. Semiconductor optical amplifiers (SOA) are used to provide ultra-wideband (UWB) seamless amplification over more than 100 nm, a promising way to scale the throughput compared to conventional systems using EDFA with bandwidth less than 40 nm. We show that custom UWB SOA can enable WDM transmission in high power regime, and we demonstrate UWB WDM experimental transmissions leveraging the SOA bandwidth. In particular, the design of specific amplification schemes is presented, and the nonlinear impairments arising from UWB spectrum transmission are characterized. Furthermore, the industry fosters the development of high symbol rate transceivers to provide cost-efficient optical WDM systems with reduced number of transceivers per fiber link. This work studies the capacity and limitations of next-generation coherent transceivers, operating at symbol-rates up to 100 GBd. We investigate the impact of equalization enhanced phase noise, which is a potentially dominant impairment at high symbol rates. We demonstrate high symbol rate transmissions, from regional distances to ultra-long-haul subsea distances in laboratory conditions, as well as in a field trial over a live commercial traffic network. Using probabilistic constellation shaping and powerful forward error correcting codes, we show the flexibility provided by high symbol rate transceivers to address the different transmission cases that constitute the core of the Internet communication network
Pellevrault, Sébastien. "Contribution à l’optimisation de transmissions optiques ultra haut débit à 40 Gb/s". Paris 11, 2008. http://www.theses.fr/2008PA112262.
Pełny tekst źródłaAn original equivalent Bit-Error-Rate (BER) extraction method (named ETO method) is developed for amplified, ultra high bit rate (40 Gb/s), high quality optical communication systems. This work was undertaken in the framework of the CARRIOCAS project which develops a 40 Gb/s experimental network. An experimental 40 Gb/s optical links caracterisation setup was developed for validation of the method. The ETO method is based on the statistical analysis of pseudorandom (PRBS) data waveforms sampled by a high frequency oscilloscope. The statistical analysis takes into account the ASE noise from the optical amplifier (Chi-square statistics) and the photoreceiver noise (Gaussian noise). Random Jitter and Inter-Symbol-Interference are also considered. Our method is faster for very low BER (less than than 10-12), than the direct measurement method of error counting. This method enables to derive the BER associated figures such as the BER contour or the bathtub curves up to 100 times faster than traditional methods. Good agreement in BER results with the direct BER counting method is verified experimentally up to 43. 2 Gb/s. The method has been successfully tested on CARRIOCAS modulators and on 2. 5 Gb/s VCSELs systems with multimodes fibers. These tests show the generality of the ETO method
Bramerie, Laurent. "Étude de la régénération optique dans les systèmes de transmissions à très haut débit". Rennes 1, 2004. http://www.theses.fr/2004REN1E004.
Pełny tekst źródłaLe, Pipec Mathieu. "Analyse d'une filière d'interconnexion adaptée aux systèmes de transmissions à haut débit par fibres optiques". Nantes, 2007. http://archive.bu.univ-nantes.fr/pollux/show.action?id=9bf42af7-1aed-4b46-a757-407ce4b059ad.
Pełny tekst źródłaThe main consequence of rising data rates in high density optical fibre telecommunications systems is the need for ever increasing component integration in both receiver and transmitter front ends. This observation has governed the work of this thesis which is devoted to helping the designer to make the right choice in the key area of interconnection technologies and to propose design rules for implementing these technologies. The first two chapters of this thesis describe the architectures of commonly deployed high data rate optical fibre systems. The principal components used in these systems are also presented as are their main characteristics. The second part concerns the selection of the right interconnection technology taking into consideration the system performances required and the constraints imposed by the necessities of component integration. A theoretical electromagnetic study of appropriate propagating structures is backed up by measurement of these structures and confirms the interest of conductor backed coplanar waveguide structures for this application. The final part of this work introduces the notion of integration with regard to a classical component such as a packaged Mach-Zehnder modulation driver and the resulting influence on the overall optical fibre system performance as measured by eye diagram and Bit Error Ratio. The analysis of the results of the electromagnetic simulation of the proposed structures allows us to propose equivalent circuit models of the transitions developed, which can be readily integrated into circuit simulators
Vanstraceele, Christophe. "Turbo codes et estimation paramétrique pour les communications à haut débit". Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2005. http://tel.archives-ouvertes.fr/tel-00133951.
Pełny tekst źródłaLestra, Alexis. "Contribution à l'étude de composants intégrés de type laser/modulateur pour transmissions optiques à haut débit". Grenoble INPG, 1996. http://www.theses.fr/1996INPG0142.
Pełny tekst źródłaRoblot, Sandrine. "Caractérisation des couplages électromagnétiques dans les réseaux filaires cuivre en vue d'optimiser les transmissions à haut débit". Phd thesis, Limoges, 2007. https://aurore.unilim.fr/theses/nxfile/default/7443f7de-a22c-45e0-9a5d-3d563f1caced/blobholder:0/2007LIMO4026.pdf.
Pełny tekst źródłaThe specificity of xDSL (Digital Subscriber Line) and PLC (Power Line Communications) systems lies in the fact that they reuse the existing networks such as telephonic infrastructure and power line network. These techniques have the significant advantage of optimizing the use of these media of communication. Nevertheless, those last were not initially intended to transmit high bit rate signals and their use at higher frequencies involves some problems of Electromagnetic Compatibility (EMC). This way the main concern of this PhD work consists in studying EMC aspects in wire networks that support high bit rate signals, considering the physical characteristics of the various media of transmission. Some innovative solutions are proposed for reducing crosstalk in multiconductor telephonic networks transmitting xDSL signals and for improving the transfer function of power line networks supporting PLC systems
Roblot, Sandrine. "Caractérisation des couplages électromagnétiques dans les réseaux filaires cuivre en vue d'optimiser les transmissions à haut débit". Phd thesis, Université de Limoges, 2007. http://tel.archives-ouvertes.fr/tel-00257975.
Pełny tekst źródłaChoumane, Houtaï. "Etude de dispositifs tout-optiques à absorbants saturables ultra rapides pour application aux transmissions optiques à très haut débit". Paris 11, 2002. http://www.theses.fr/2002PA112256.
Pełny tekst źródłaThis work of thesis is articulated around the design, the development, and the validation of a new passive all-optical regenerator compatible with high bit rate signals. The followed approach is based on ion irradiated quantum wells saturable absorber component inserted in a vertical microcavity. We first of all succeeded in conceiving a new generation of components with high-performance saturable absorber with regard to their commutation power while keeping a spectral band-width compatible with WDM systems. This optimization enabled us to extend the operation range of our components to signals of higher bit rate (from 20 to 40 Gbit/s). This new generation of components could make the improvements discounted thanks to an original fabrication process, reliable and reproducible. This original technology enabled us to cross a significant step in the control of the fabrication process of our components. In addition to the reproducibility of this process, an excellent homogeneity of the fabricated components was shown. An experimental characterization (at low and high rates) enabled us to determine the optimal points of operation of the components as well as the ideal system parameters (power, wavelength, etc). Thanks to their reduced commutation energy, the new components integrated in a 2R regenerator diagram make it possible to carry out a quasi-transoceanic transmission at 40 Gbit/s and Q=11,3. Optimizations, design as well as the validation of the functional characteristics of a saturable absorber module with 4 fibered channels were also shown
Meliani, Chafik. "Circuits intégrés amplificateurs à base de transistors HEMT pour les transmissions numériques à très haut débit (≥40 Gbit/s)". Paris 7, 2003. http://www.theses.fr/2003PA077172.
Pełny tekst źródłaMELIANI, Chafik. "Circuits intégrés amplificateurs à base de transistors HEMT pour les transmissions numériques à très haut débit (>=40 Gbit/s)". Phd thesis, Université Paris-Diderot - Paris VII, 2003. http://tel.archives-ouvertes.fr/tel-00007587.
Pełny tekst źródłaLegrand, Anne. "Etude des amplificateurs paramétriques à fibre optique pour leur utilisation dans les systèmes de transmissions optiques haut débit multiplexées en longueur d'ondes". Limoges, 2005. http://aurore.unilim.fr/theses/nxfile/default/da5f88b6-5557-4d4e-9780-8eebb1613012/blobholder:0/2005LIMO0031.pdf.
Pełny tekst źródłaTo increase the quantity of information transmitted in optical telecommunications networks, equipment suppliers wish to extend the spectral band, which requires new optical amplifiers. Fibre optical parametric amplifiers can provide a broadband gain. During this thesis work, the operating conditions have been studied so as to check their adequacy with the constraints of optical transmission systems. This study showed that a parametric amplifier could produce a band of gain that fulfils the requirements of wavelength-multiplexed transmissions. However interactions between channels should be further studied. Besides, cautious attention must be paid to the optical pumping device. This work aimed in better defining its essential characteristics to resist the harmful effect of the Brillouin diffusion and to ensure low noise amplification without distortions of the channels
Ndo, Gaetan. "Etude et optimisation de techniques de réduction de bruit impulsif pour transmissions haut débit sur lignes à courants porteurs en contexte résidentiel". Télécom Bretagne, 2010. http://www.theses.fr/2010TELB0153.
Pełny tekst źródłaThis thesis aims at improving some asynchronous impulsive noise reduction techniques for broadband transmissions over indoor power lines. Indeed, beside the particular physical properties of this type of medium, asynchronous impulsive noise remains one of the main causes of performance degradation in powerline communications (PLC). Such an impairment is usually coped with retransmission strategies at the price of a spectral efficiency loss. Although several other countering strategies are proposed in the literature, only very few of them exhibit a reasonable complexity. In particular, the clipping and the blanking approaches present a very good trade-off between the impulsive noise mitigation and the complexity of the implementation. In this thesis, an optimization of the threshold determination, which is usually empirically done, is performed analytically both for the clipping and the blanking non-linearities. Moreover, some adaptive receiver structures for asynchronous impulsive noise reduction over PLC are proposed. On the other hand, because of its good frequency selectivity features and its spectral efficiency gain compared to cyclic-prefix OFDM (CP-OFDM), the OFDM/Offset QAM (OFDM/OQAM) can be seen as an alternative multicarrier modulation scheme for transmission over power lines. Since no study was dedicated to analyze such a modulation in an impulsive environment, this thesis investigates the performance behavior of an OFDM/OQAM modulated system corrupted by asynchronous impulsive noise. Furthermore, a thorough Log-Likelihood Ratio (LLR) computation is derived for coded OFDM/OQAM transmissions under realistic PLC conditions, and the performance results are compared with those obtained with coded CP-OFDM. Finally, a new diversity of the OFDM/OQAM modulation is pointed out in this work
Petit, Ferrufino Juan Mauricio. "Dual Electroabsorption Modulated Laser: étude et caractérisation d'une nouvelle source optique laser-modulateur intégrés pour les transmissions numériques haut-débit et les applications Radio-sur-Fibre". Phd thesis, Télécom ParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00579997.
Pełny tekst źródłaPetit-Ferrufino, Juan. ""Dual electroabsorption modulated laser" : étude et caractérisation d'une nouvelle source optique laser-modulateur intégrés pour les transmissions numériques à haut débit et les applications radio-sur-fibre". Paris, Télécom ParisTech, 2010. https://pastel.hal.science/pastel-00579997.
Pełny tekst źródłaThis thesis is related to the physical layer of a terrestrial optical transmission system for a metropolitan network. Our first investigation deals with an optical device, the Electroabsorption Modulated Laser (EML) which is used to constitute the optical source of medium span optical link thanks to its low price, low consumption and small foot print. The work is done in collaboration with an industrial optoelectronics maker, the GIE Alcatel-Thales III-V Lab, We propose an original technique of pre-chirping obtained by modulating the laser in addition to the electro-absorption modulator (MEA). The purpose of this thesis is to develop a novel modulation scheme of the EML in order to overcome the limits set by the chromatic dispersion and nonlinear effects in the transmission fibre. The principle has been demonstrated in the literature with a separate laser and a modulator but never with an integrated device. The technique is based on a pre-compensation of the chromatic dispersion by applying a modulation to the laser of the EML and then the signal is modulated by the MEA. Within the scope of this research work, we have demonstrated experimentally the first increment of the usual distances from around 80 km upto 160 km with a monolithic component and no dispersion compensating element. Radio-over-Fiber application for optical access networks has also been explored, it is also based on an analogue dual modulation, this time tuned so as supress one modulation sideband. This modulation format can carry very high-speed IQ signals over 100 km excluding the periodic degradation of the data signal induced by chromatic dispersion obtained with double-sideband modulation
Le, Berre Denis. "Contribution à la conception de circuits de commande laser pour les transmissions analogique et numérique à très haut débit. Applications à la réalisation d'un circuit large bande en technologie microruban". Brest, 1997. http://www.theses.fr/1997BRES2018.
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