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Wijaya, Shierly. "Fixed-point realisation of erbium doped fibre amplifer control algorithms on FPGA." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0132.
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The realisation of signal processing algorithms in fixed-point offers substantial performance advantages over floating-point realisations. However, it is widely acknowledged that the task of realising algorithms in fixed-point is a challenging one with limited tool support. This thesis examines various aspects related to the translation of algorithms, given in infinite precision or floating-point, into fixed-point. In particular, this thesis reports on the implementation of a given algorithm, an EDFA (Erbium-Doped Fibre Amplifier) control algorithm, on a FPGA (Field Programmable Gate Array) using fixed-point arithmetic. An analytical approach is proposed that allows the automated realisation of algorithms in fixedpoint. The technique provides fixed-point parameters for a given floating-point model that satisfies a precision constraint imposed on the primary output of the algorithm to be realised. The development of a simulation framework based on this analysis allows fixed-point designs to be generated in a shorter time frame. Albeit being limited to digital algorithms that can be represented as a data flow graph (DFG), the approach developed in the thesis allows for a speed up in the design and development cycle, reduces the possibility of error and eases the overall effort involved in the process. It is shown in this thesis that a fixed-point realisation of an EDFA control algorithm using this technique produces results that satisfy the given constraints.
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Mamud, Marcelo Leme. "Desenvolvimento de recurso de aprendizagem inteligente no campo de comunicações ópticas utilizando simulação computacional." Universidade Presbiteriana Mackenzie, 2010. http://tede.mackenzie.br/jspui/handle/tede/1518.
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Previous issue date: 2010-03-03<br>Fundo Mackenzie de Pesquisa<br>In recent years there have been some proposals to develop educational tools using multimedia and interactive resources. However, most of them just transpose the traditional materials to the computer screen. The reason for this work is the gap of didactic materials to explore important subjects about photonics and optical communication systems, specially the lack of tools related to Erbium Doped Fiber Amplifier (EDFA) learning. The aim of this research is to provide at the LCMS MOODLE open platform an Intelligent Learning Resource to support EDFA study, providing a set of Learning Objects more suitable for the study of the base concepts needed to optimise the use of the computer simulation tool. For so, this research
presents the development of an Intelligent Learning Resource for Electric Engineering, Physics, and related fields, in which students can learn about optical communications, in particular EDFA. The proposal is to give autonomy to the students, which manage their own
study time, and fulfill the basement and prerequisites needed to understand the subject and complete the tasks proposed. Moreover, the learning resource proposes the navigation through a concept map based on a multiagent system architecture, providing an individual treatment according to each student profile. The insertion of a society of agents in the concept map, in order to observe, collect information about the user background profile, and also act in the virtual environment, suggesting the study of the most appropriate learning objects. The learning resource developed can stimulate the students to understand how amplifiers are designed for a practical application, and the parameters that should be considered in a project. The Artificial Intelligence techniques used for the development of the learning resource consider the learner differences in a way to adapt the system actions according to each student background.<br>Nos últimos anos foi possível observar o desenvolvimento de propostas de ferramentas digitais de ensino, utilizando interatividade, recursos multimídia, entre outros. Entretanto,
parte destas propostas reflete as deficiências características das metodologias de ensino tradicionais. Este trabalho apresenta o desenvolvimento de um Recurso Digital de Aprendizagem, baseado em técnicas de Inteligência Artificial, com aplicação no campo de comunicações ópticas. São apresentadas as técnicas e aplicativos de suporte para a construção deste recurso, incluindo as estratégias para adaptação da navegação de acordo com os prérequisitos e perfis dos aprendizes. Foi utilizada a tecnologia de mapas conceituais e sistemas multiagentes, integrados a Objetos de Aprendizagem. Os agentes computacionais, inseridos em cada nó do mapa, têm a missão de atuar sobre o ambiente de aprendizagem, sugerindo o estudo e acesso aos Objetos de Aprendizagem mais apropriados, conforme os resultados sobre
o perfil do usuário. Trata-se de uma abordagem pedagógica, que conta com interatividade, recursos audiovisuais e disponibilidade para o aluno administrar seu próprio tempo e da maneira mais flexível, aumentando a eficiência dos estudos. A partir da observação das dificuldades encontradas por estudantes da área, foi possível determinar os requisitos do projeto. A motivação para o desenvolvimento, na área de amplificadores ópticos de fibras dopadas por érbio (EDFA), surgiu pela dificuldade e carência de materiais didáticos no campo de pesquisa de engenharia de telecomunicações. Um dos principais problemas no estudo de EDFA é a abordagem matemática utilizada na literatura da área, exigindo domínio de conceitos avançados em cálculo. A partir do Recurso de Aprendizagem implantado, é possível verificar a estratégia de extrair a partir de diversos recursos tecnológicos como, por exemplo, interatividade, multimídia, mapas conceituais, inteligência artificial e simulação computacional, maneiras para estimular a aprendizagem significativa sobre os conceitos
abordados.
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Dimopoulos, C. "Study of dynamic phenomena in WDM optical fibre links and networks based on EDFAs." Thesis, University of Essex, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327071.
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Ono, Shunsuke. "Optical properties and gain characteristics of erbium-doped fiber amplifier." Kyoto University, 2005. http://hdl.handle.net/2433/144986.
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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(人間・環境学)<br>甲第11688号<br>人博第294号<br>新制||人||73(附属図書館)<br>16||185(吉田南総合図書館)<br>23331<br>UT51-2005-D437<br>京都大学大学院人間･環境学研究科環境相関研究専攻<br>(主査)教授 村中 重利, 教授 林 哲介, 助教授 田部 勢津久<br>学位規則第4条第1項該当
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Khaleghi, Farideh. "Erbium-doped fiber amplifier applications in WDM transport systems and networks." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/10194.
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New expressions are derived for wavelength-dependent gain variations of the EDFA due to changes in the pump power, total input power, and the power distribution among different wavelength channels in a wavelength-division multiplexing (WDM) system. A simple method is proposed to compensate for the changes in the amplifier gain spectrum. This method is based on adjusting the pump power. Two different novel gain equalization techniques are presented. A tunable coherent optical transversal filter is designed as a gain equalizer. The filter operation is based on coherently combining the tapped signals. It is shown that, although the N tapped signals after being weighted according to the filter parameters are recombined by a tree of 2 x 2 couplers, the coupling loss experienced at the output is much less than the noncoherent coupling loss (10log(N)). For a multi-wavelength input, the spectrum of the amplifier output power is evaluated before and after the equalizer, using the numerical full spectrum model of the amplifier. The impact of the laser phase noise on the performance of this equalizer is studied. Another gain equalization technique is presented where high- and moderate-inversion EDFAs are used alternatively in order to equalize both signal power and signal-to-noise ratio (SNR) of multiple wavelength channels in WDM transmission systems. This technique is based on the fact that the gain slope is a function of the inversion level in amplifiers. This is confirmed experimentally. The performance of the equalized WDM system is examined by a numerical analysis based on the full spectrum model of the amplifier. The interferometric conversion of the phase-to-intensity noise is studied. The probability density function (pdf) of the intensity noise at the output of a multi-tap filter is derived. The degradation of the filter response is evaluated. The power penalty due to this noise is derived for amplitude modulated signals modulated using different bit rates. The power penalty due to interferometric noise caused by multiple reflections is also derived. A novel bidirectional EDFA configuration is proposed where the power penalty associated with the amplifier due to both the signal-spontaneous noise and the interferometric noise is substantially reduced. The experimental results are presented where a gain of 36 dB is achieved, and a 2.5 Gb/s bidirectional transmission over 300 km is realized. The power penalty is as low as 0.5 dB. Application of EDFA in an optical network is presented. The multi-access scheme in this local network is code-division multiple access (CDMA). A new correlator receiver architecture for noncoherent optical CDMA networks is proposed based on a modified version of unipolar-bipolar correlation functions for known bipolar codes. These functions are studied. Average bit error rate (BER) performance is evaluated for this architecture. The results indicate that bipolar capacity can be achieved by this architecture.
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Males, Mladen. "Suppression of transient gain excursions in an erbium-doped fibre amplifier /." Connect to this title, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0157.
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Males, Mladen. "Suppression of transient gain excursions in an erbium-doped fibre amplifier." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0157.
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This thesis reports original work on suppression of transient gain excursions in an erbium-doped fibre amplifier (EDFA). The work presented in this thesis is a detailed investigation of four closed-loop systems that control the EDFA gain dynamically. The performance of the four closed-loop systems is evaluated by analytical work, supplemented by computer simulations and insystem measurements performed on a hardware EDFA. In addition, a stability analysis of the four closed-loop systems is presented. In the stability analysis presented in this thesis, nonlinear nature of the four closed-loop systems is taken into consideration. In the stability analysis, in addition to proving that the four closed-loop systems considered are stable, it is proven that for any practical values of the EDFA gain at the initial time of observation, the EDFA gain is restored to the desired value in steady state. These outcomes of the stability analysis are supported by simulation results and experimental results. Errors in system modelling, change in the operating point of the nonlinear closed-loop system, and measurement noise are important aspects of practical implementations of systems that control the EDFA gain dynamically. A detailed analysis of the effects these practical aspects have on the performance of the four closed-loop systems considered is presented. The analysis is validated using computer simulations and experimental measurements. In most of the work reported in the literature on controlling the EDFA gain, controllers that include feedforward and/or feedback components are employed. In the traditional approaches to combining the feedforward and the feedback components, large transient excursions of the EDFA gain can still occur due to errors in the control provided by the feedforward component. In this thesis, a novel approach to combining the feedforward and the feedback components of the controller is presented. Based on the analytical work, the computer simulations and the experimental work presented in this thesis, the novel approach provides a significant reduction in the excursions of the EDFA gain in the transient period.
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VELIZ, RICARDO ALBERTO OLIVARES. "POWER TRANSIENTS STUDY AND CONTROL TECHNIQUES IN WDM OPTICAL NETWORKS SUPPORTED BY DOPPED ERBIUM FIBER AMPLIFIER CASCATES EDFAS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2000. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=8371@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO<br>UNIVERSIDAD TÉCNICA FEDERICO SANTA MARÍA<br>Neste trabalho são estudadas cascatas de amplificadores a
fibra óptica dopada com Érbio (EDFAs) inseridas em redes
ópticas multiplexadas em comprimento de onda (WDM).
Modelos numéricos são desenvolvidos e implementados para
estudar o efeito da variação do número de canais
amplificados pela cascata de EDFAs no desempenho de redes
WDM submetidas a funções de adição/retirada de canais.
Considerando condições em estado estacionário, é
desenvolvida uma inovadora configuração amplificadora WDM,
que oferece robustez e bom desempenho diante da carga
variável de canais transportados em enlaces de redes
ópticas WDM. Transientes de potência em cascatas de EDFAs,
assim como técnicas de compensação dos mesmos, são
analisados. O estudo permite avaliar as vantagens e
limitações dos modelos dinâmicos apresentados, assim como
o desempenho das técnicas de controle de transientes de
potência em cascatas de EDFAs, em condições realistas de
operação.<br>In this work Erbium Fiber-Doped Amplifiers (EDFAs)
cascades in Wavelength Division Multiplexed optical
networks (WDMs) are studied. Computer numerical models are
developed and implemented in order to study the effect of
the EDFA channel number variation in the performance of
optical networks submitted to channels add/drop function.
Initially, steady state conditions are considered. Then, a
WDM amplifier configuration formed by EDFAs, power
compensators and optical filters is developed. This
configuration - which is a novel one - has shown to be
robust and to offer a good performance, in regard to the
variable load of the transported channels in WDM network
links. In order to obtain a more detailed study of power
transients in cascades of EDFA, two dynamic computer
models of these amplifiers are implemented: (i) - a simple
one, that neglects the amplified spontaneous emission
(ASE) and; (ii) - a second one, which rigorously consider
all noise-derived effects in an EDFA cascade. In order to
achieve power transients control, several compensation
techniques are studied and implemented. A comparative
analysis, concerning the efficiency of the above mentioned
compensation techniques is carried out. Advantages and
limitations of two dynamic introduced models were also
evaluated, as well the control techniques of power
transients in EDFA cascades.
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Hoffman, Mark Brandon. "Sub-picosecond pulse propagation in an erbium-doped fiber amplifier with ion-induced dispersion." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/14961.
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Malik, Bilal Hameed. "Erbium-doped fiber ring laser tuning using an intra-cavity Fabry-Perot filter." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1779.
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Ferreira, João Carlos de Melo. "Fiber amplifiers in transparent and dynamic optical networks." Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14090.
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Doutoramento em Engenharia Eletrotécnica<br>In this thesis a study of optical fiber amplifiers in the context of
transparent and dynamic optical networks is performed.
We propose and validate a simplified model to estimate the gain profile
and amplified spontaneous emission (ASE) noise of broadband counterpumped
Raman fiber amplifiers (RFAs). The proposed model requires
very low computational resources and it is suitable to be used in
network planning tools. Based on the proposed model, we also present
an algorithm to design flat gain counter-pumped RFAs for the extended
C-band with low computational requirements.
We experimentally verify that the pump-reflecting RFA presents a higher
transient response due to channels add/drop, when compared to the
conventional counter-pumped RFA. This makes this amplifier
configuration unsuitable for transparent and dynamic optical networks.
To mitigate the transient response due to channel add/drop, a pumpcontrolled
gain-locked system based on the monitorization of the
reflected pump power is proposed and validated numerically and
experimentally. Following this approach, an efficient low-cost RFA
suitable for dynamic optical networks is proposed.
The dependence of the dynamical response of erbium-doped fiber
amplifiers (EDFAs) on the pump wavelength, pump power, and
temperature due to spectral hole burning (SHB) and site dependent
pumping (SDP) is experimentally investigated. A dependence of the
dynamic response on the pump wavelength, for amplifiers pumped
around 1480 nm, is shown. In order to explain this dependence, the
impact of SDP on the performance of EDFAs pumped at wavelengths
around 1480 nm is investigated, both experimentally and numerically.
As a result, an improved model incorporating the SDP effect for twolevel
EDFAs is derived and experimentally validated.<br>Nesta tese é feito um estudo sobre amplificadores de fibra ótica no
contexto de redes óticas transparentes e dinâmicas.
Propomos e validamos um modelo simplificado para estimar o perfil do
ganho e do ruído de emissão espontânea amplificada (ASE), para
amplificadores de Raman (RFAs) contra propagantes. O modelo
proposto requer baixos recursos computacionais e é adequado para ser
usado em ferramentas de planeamento da rede. Com base no modelo
proposto, apresentamos também um algoritmo com requisitos
computacionais baixos para desenhar RFAs contra propagantes com
ganho constante para a banda C estendida.
Verificamos experimentalmente que um RFA contra propagante com
reflexo da potência da bomba devido à adição/remoção de canais
apresenta uma resposta transiente mais elevada, quando comparado
com um RFA contra propagante convencional. Isto torna esta
configuração inadequada para redes óticas transparentes e dinâmicas.
Para mitigar a resposta transitória devido à adição/remoção de canais,
um sistema de controlo do ganho baseado na monitorização da
potência da bomba refletida é proposto e validado numérica e
experimentalmente. Seguindo esta abordagem, um RFA contra
propagante eficiente e de baixo custo adequado para redes óticas
dinâmicas é proposto.
A dependência da resposta dinâmica dos amplificadores de fibra
dopada com érbio (EDFAs) em função do comprimento de onda da
bomba, da potência da bomba e da temperatura devido ao spectral hole
burning (SHB) e site dependent pumping (SDP) é investigada
experimentalmente. Nos resultados obtidos é mostrada a dependência
da resposta dinâmica em função do comprimento de onda da bomba,
para amplificadores bombeados em torno de 1480 nm. Para explicar
esta dependência, o impacto do SDP no desempenho de EDFAs
bombeados em comprimentos de onda em torno de 1480 nm é
investigado, tanto experimental como numericamente. Como resultado,
um modelo mais completo, incorporando o efeito SDP para EDFAs de
dois níveis é derivado e validado experimentalmente.
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Goel, Nitin Kumar. "Development of "Core-Suction" Technique for Fabrication of Highly Doped Fibers for Optical Amplification and Characterization of Optical Fibers for Raman Amplification." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29302.
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This thesis presents a novel technique named "Core Suction" for fabricating optical fiber preforms for manufacturing highly doped fibers (HDFs) for optical amplification (Raman effect based or Erbium fiber based). The technique involves drawing the molten non-conventional core glass material into the silica cladding tube to form the preform. The developed technique is simple, inexpensive and shows great potential for fabricating preforms of highly nonlinear non-conventional multi-component glasses as the core material. Preforms were made with various core glasses such as Schott SF6, Lead-Tellurium-Germanate, Lead-Tellurium-Germanate- Neodymium -Erbium and MM2 in silica cladding tubes and then pulled into fibers.
The fabricated fibers were measured for refractive index profile, loss spectrum and spontaneous Raman spectra. Elemental analysis of the fiber samples was also performed using an electron microprobe. Erbium doped fiber amplifiers (EDFAs) were setup using 30 cm, 5cm and 1 cm lengths of fabricated erbium doped fibers and their gain spectra measured. The distributed gain spectrum for an EDFA was also measured using an optical frequency domain reflectometery (OFDR) technique. Commercial dispersion compensated fiber (DCF) with very high GeO2 doping was used to setup a Raman amplifier and the gain spectrum measured.
One of the needs of Raman amplification in optical fibers is to predict an accurate Raman gain, based on the fiber's refractive index profile. A method of predicting Raman gain in GeO2 doped fibers is presented and the predicted Raman gain values are compared with the measured ones in the same fibers. Raman gain issues like the dependence of the Raman gain on the GeO2 concentration, polarization dependence were taken into account for the gain calculations. An experimental setup for Raman gain measurements was made and measurement issues addressed. Polarization dependence of the Raman gain in one kilometer of polarization maintaining fiber was also measured.<br>Ph. D.
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Verlinden, Nicholas H. P. "The excited state absorption cross section of neodymium-doped silica glass fiber in the 1200-1500 nm wavelength range." Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-072508-145557/.
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Herbster, Adolfo Fernandes. "Projeto de amplificadores a fibra dopada com érbio para sistemas baseados em multiplexação modal." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18155/tde-06082015-144812/.
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Os sistemas ópticos atuais, baseados em fibras monomodo, operam próximos ao limite teórico da capacidade. Sistemas ópticos baseados em multiplexação modal (Mode Division Multiplexing – MDM) possibilitam o aumento da capacidade do sistema por meio do uso de fibras de poucos modos. Nestes sistemas, a propriedade de ortogonalidade entre os modos propagantes permite que cada modo espacial carregue um sinal óptico específico. O amplificador à fibra dopada com érbio (Erbium-Doped Fiber Amplifier – EDFA) segue fundamental para assegurar a transmissão em longas distâncias. No entanto, devido às distintas distribuições de intensidade dos modos que compõem o sinal de entrada, cada modo experimenta diferentes valores de ganho. Desta forma, o objetivo principal no projeto de EDFAs de poucos modos (Few-Mode Erbium-Doped Fiber Amplifier – FM-EDFA) é determinar os melhores parâmetros opto-geométricos da fibra para produzir uma amplificação eficiente. A metodologia normalmente empregada é baseada na resolução das equações de taxa e de propagação. Nesta tese, é proposta uma metodologia alternativa de projeto de FM-EDFA, baseada em uma nova figura de mérito. Este parâmetro quantifica o nível de inversão da população dos íons na fibra a partir da integral de superposição (overlap integral), considerando tanto o perfil de dopagem da fibra dopada com érbio para poucos modos (Few-Mode Erbium-Doped Fiber – FM-EDF) quanto as distribuições de intensidade dos sinais de entrada e de bombeio. A aplicação desta metodologia permite reduzir, em cerca de 25-40 vezes, o número de resoluções das equações de taxa e de propagação e, consequentemente, diminuir o tempo de processamento e reduzir o esforço computacional. Como consequência da maior velocidade de processamento, torna-se possível a aplicação de métodos de otimização mais rigorosos, permitindo uma busca em um espaço irrestrito de soluções. Especificamente, a partir de uma metodologia baseada em algoritmos genéticos, obteve-se um perfil de dopagem otimizado. É também demonstrado que os perfis com geometria circular exibem melhores características, como excelente desempenho do FM-EDFA e maior facilidade de fabricação. Por meio da análise da figura de mérito, é mostrado que o desempenho do FM-EDFA é afetado pelas características do modo de bombeio. Finalmente, o desempenho de um sistema óptico MDM é avaliado, simulado por meio da integração entre as ferramentas MatLab® e VPItransmissionMakerTM, comprovando a necessidade do projeto de um amplificador específico para sistemas MDM.<br>Modern optical systems based on single-mode fiber, operate close to the theoretical capacity limit. By using few-mode fibers, optical systems based on modal division multiplexing (MDM) allows increased system capacity. In these systems, orthogonality between the propagating modes allows each spatial mode to carry a specific optical signal. The erbium doped fiber amplifier (EDFA) remains essential to ensure long distance transmission. However, due to the distinct intensity profile distributions of the modes which comprise the input signal, each mode experiences a different value of optical gain. Thus, the main objective in the few-mode EDFA design (FM-EDFA) is to determine the best opto-geometrical fiber parameters in order to produce an efficient amplification. The methodology normally used is based on the simultaneous resolution of the rate and propagation equations. In this thesis, we propose an alternative methodology for the FM-EDFA design, based on a new figure of merit which quantifies the level of population inversion for the Er ions in the fiber, by means of a overlap integral considering both the doping profile of the few-mode erbium doped fiber (FM-EDF) as well as the intensity distributions of the optical signals and pump beams. This methodology reduces, by a factor of 25-40, the number of resolutions of the rate and propagation equations, thereby decreasing processing time and computational effort. As a consequence of the improved processing speed, it becomes possible to apply more rigorous optimization methods in an unrestricted solution space. Specifically, by using a genetic algorithm technique, we obtained an optimized doping profile. It is also shown that profiles with circular geometry exhibit improved features, such as excellent FM-EDFA performance and ease of manufacturing. By analyzing the figure of merit, it is shown that the FM-EDFA performance is affected by the characteristics of the pump mode. Finally, the performance of an MDM optical system is evaluated, by integrating Matlab and VPI simulation tools, to demonstrate the need for specific amplifier designs in MDM systems.
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Freire, Hermelo Maria. "Amplifier control using machine learning and coloured optical packet switching node design in optical networks." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAS024.
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Le débit de données et la consommation d’énergie sont les principaux défis auxquels doivent faire face les réseaux optiques. Afin de réduire la consommation d’énergie, les réseaux opérateurs de transport optiques basés sur le concept de commutation de circuits optiques (OCS), deviennent optiquement transparents, réduisant les conversions optique/électrique (O/E) et électrique/optique (E/O). Pour faire face à l’augmentation du débit de données, on utilise des formats de modulations complexes et la technique de multiplexage en polarisation et on économise le spectre des fibres optiques en considérant une grille en longueurs d’onde plus flexible que la grille fixe ITU-T WDM. On développe des transpondeurs flexibles capables de sélectionner différents formats de modulation et longueurs d’onde; on développe également des multiplexeurs optiques d’insertion/extraction reconfigurables (ROADMs) basés sur des commutateurs sélectifs en longueur d’onde (WSSs). Ces réseaux flexibles prennent également en compte un trafic plus dynamique. Dynamisme et flexibilité impactent fortement les équipements des réseaux optiques, y compris les nœuds optiques d’un point de vue couche physique et couche de contrôle. Lorsque des canaux ou demandes sont ajoutés et/ou extraits, l’excursion de puissance optique des amplificateurs à fibre dopée à l’erbium (EDFAs) varie temporellement ce qui implique qu’elle doit être contrôlée dynamiquement. Dans ce contexte, le concept de réseau défini par le soft (SDN: Software Defined Network) prend tout son sens et l’introduction des techniques d’apprentissage machine (ML) permet d’entrevoir une aide au concept de SDN pour la gestion et le contrôle dynamique des réseaux optiques. Dans la première partie de ce travail de thèse, nous étudions l’excursion de puissance optique dans les réseaux de transport optiques dynamiques. Afin d’en atténuer les effets indésirables, nous introduisons et mettons en œuvre un module de prédiction et de pré-compensation de l’excursion de puissance en utilisant les méthodes ML. Comme les altérations de la couche physique (PLIs : Physical Layer Impairments) s’accumulent le long du chemin optique entre les noeuds source et destination de réseau, nous associons à l’excursion de puissance optique le rapport signal/bruit optique (OSNR: Optical Signal to Noise Ratio) et le taux d’erreur binaire (BER: Bit Error Rate), afin d’estimer la qualité de transmission (QoT: Quality of Transmission) de nouvelles configurations de canaux. Ensuite, en utilisant l’approche d’apprentissage par renforcement (RL), nous attribuons un format de modulation et une longueur d’onde aux différents canaux de façon automatique afin de réduire la probabilité de blocage des demandes entrantes dans les nœuds optiques. Dans la deuxième partie de ce travail de thèse, nous présentons notre contribution en tant que partenaire du projet ANR N-GREEN. Le principal objectif de N-GREEN est de proposer une nouvelle génération de routeurs peu consommateurs en énergie en considérant une architecture de réseau. Dans ce projet, nous abordons une architecture de réseau basée sur la commutation optique de paquets colorés (OPS: Optical Packet Switching) en rupture avec celle considérée dans la première partie de cette thèse. Dans le cadre de ce projet, nous avons caractérisé expérimentalement un commutateur optique 2 x 2 basé sur des amplificateurs optiques à semi-conducteurs (SOAs). Cette caractérisation nous a permis de valider un réseau en anneau constitué de 10 noeuds en cascade. En envisageant une configuration de commutateur 16 x 16, la caractérisation expérimentale, dans des configurations à canal unique et WDM, laisse entrevoir des possibilités intéressantes pour la transmission de données à très haut débit<br>Data rate and energy consumption are the major concerns in optical networks. In order to reduce energy consumption, transport operator networks based on optical circuit switching (OCS) concept, are becoming optically transparent, reducing optical to electrical (O/E) and electrical to optical (E/O) conversions. To face data rate increase, complex modulation formats and dual-polarization systems are considered and fiber spectrum is saved using network resources in a more efficient way, giving rise to a flexible frequency grid. Flexible transponders are developed to tune modulation formats and wavelengths and reconfigurable optical add/drop multiplexers (ROADMs) based on wavelength selective switches (WSSs) are studied. Flexible networks consider also a more dynamic traffic. Dynamism and flexibility lead to a deep transformation of the optical networks, including optical nodes, from both physical and control layer point of view. When channels are added and/or dropped, optical power excursion from erbium doped fiber amplifiers (EDFAs) has to be controlled dynamically. In that context, software defined networking (SDN) assisted by machine learning (ML) techniques is envisaged as promising candidate for the management and the dynamic control of optical networks. In this context, in the first part of our PhD work, we deal with optical power excursion in dynamic optical transport networks. In order to mitigate undesirable effects, we introduce and implement power excursion prediction and pre-compensation module using ML methods. As physical layer impairments (PLIs) accumulate along the path, we consider optical power excursion together with optical signal to noise ratio (OSNR) and bit error rate (BER), to estimate quality of transmission (QoT) of unseen channel configurations. Afterwards, using a reinforcement learning (RL) approach, we establish an autonomous impairment aware modulation format and wavelength assignment procedure, and we show that this permits to reduce the blocking probability of the incoming demands in optical nodes. In the second part of our PhD work, in the context of the N-GREEN project from the French national agency of research, we address a disruptive network architecture based on coloured optical packet switching (OPS). The main objective of N-GREEN is to propose a new generation of energy efficient routers. In the N-GREEN project, we perform the experimental characterization of an optical 2 x 2 switch based on semiconductor optical amplifiers (SOAs). This characterization leads to the proof of concept of a ring network with 10 nodes in cascade. Envisaging a 16 x 16 switch configuration, the experimental characterization, in single channel and WDM configurations, unveil interesting possibilities for the transmission of ultra-high data rates
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Lin, Sung-Nien, and 林松年. "The Optimum Design of Natural Convection inside an EDFA (Erbium Doped Fiber Amplifier)." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/31933443192677853295.
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碩士<br>大同大學<br>機械工程研究所<br>90<br>The content of this thesis is focus on the optimization of cooling of an EDFA (Erbium Doped Fiber Amplifier). The simulation geometry of EDFA is same as far as possible with the prototype to be studied for the optimum cooling condition. The CFD analytical software, FLOTHERM, is used to do the simulations in this thesis in order to find out the optimum cooling design of EDFA. Six groups are built to be compared each other.
The results show that change of direction of gravity (i.e. how EDFA is put) influences the temperature of lasers greatly, and the position of the additional slot is an important factor for the temperature of lasers, too. The temperature of lasers is obviously varied when the direction of gravity and the position of the additional slot change even though these cases have the same area of slots. Changes of the thickness of the case of EDFA are relatively not so important for decreasing the temperature of lasers.
Cases which the top of lasers attaches the bottom surface of the EDFA top cover directly or via pure aluminum thermal pads get lower temperature of lasers. This phenomenon shows that heat sources of portable devices without fans like EDFA should conduct the heat to the case directly because conduction delivers the most of heat than those of convection or radiation. The temperature of lasers of the best case without fins in this thesis decreases almost 15℃ from the original design.
Finally, an EDFA with fins is built, and temperature of lasers decreases again, and the temperature of lasers decreases about 21.6℃ from the original design. So, only after the internal optimum design of EDFA collocating the external optimum design of EDFA comes the most decrease of temperature of lasers.
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Huang, Ming-Fang, and 黃明芳. "Wide-band hybrid EDFA/Raman Amplifiers with silica-based erbium-doped fiber." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/75201279140554048574.
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碩士<br>國立交通大學<br>光電工程所<br>91<br>The broadband hybrid amplifiers become more and more important because of the demands for high bit rate and high capacity in fiber communication systems. However, the bandwidth of the traditional erbium-doped fiber amplifiers (EDFA) is insufficient for today’s data transmission. Therefore, a wide-band hybrid amplifier, which can cover C- and L-band, will play an important role in the fiber communication system. Comparing to traditional Raman amplifier, a hybrid EDFA/Raman amplifier, consisting of the EDFA at amplification band near 1530 nm and the Raman amplifier that could have the gain at any wavelength, can give us better performance and the cost can also be reduced dramatically.
In this thesis, we propose to use 100 km single mode fibers as the gain medium of Raman amplifier, and many types of hybrid EDFA/Raman amplifiers with different pumping direction and different order of EDFA and Raman amplifier will be discussed. Here we would not use the special erbium-doped fiber as fluoride-based erbium-doped fiber. Currently, we have built the wide-band hybrid optical amplifiers. Less than 3dB gain bandwidth is close to 100nm with silica-based erbium-doped fiber amplifier combined with three-pumping wavelength for Raman amplifier.
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Chen, Chih-Yang, and 陳智揚. "Femtosecond erbium-doped fiber amplifier." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/xnyhav.
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碩士<br>國立清華大學<br>光電工程研究所<br>105<br>In this thesis, we utilize a pulse shaper to control the spectral phase of the pulse seeded to a commercial Erbium-Doped Fiber Amplifier (EDFA) system, and seek to maximize the peak power and minimize the duration of the output pulse. In theory, nonlinear effects can be suppressed when the pulse remains highly chirped during the amplification process. However, in our experiment the EDFA is composed of relatively long EDF [40 meters] compare to typical fiber amplifiers [roughly 3-5 meters], nonlinear effects still play important roles as noticeable spectral broadening is observed. In our work, an input pulse with 7.7 mW average power, 8.3 MHz repetition rate and 660 fs transform-limited (TL) pulse width [defined by full-width at half maximum (FWHM)] is seeded to our EDFA system [with 1.5 W pump power]. Amplified pulses with average power of 155 mW [before compression] and peak power of 235 kW [after ideal phase compensation] is generated when a group delay dispersion (GDD) of 3.285 ps2 is applied to the seed pulse via a pulse shaper.
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Hsu, Yaw-Wen, and 許耀文. "Applications of Erbium-Doped Fiber Amplifier." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/62932162210223025330.
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碩士<br>國立交通大學<br>光電工程所<br>90<br>In order to ensure the transmission quality of WDM systems, the optical amplifier used in WDM system should have properties such as wide bandwith, high output power and low noise figure. However, with the development of long-haul fiber transmission system, the gain-flattening technique should also be upgraded. So dynamic gain flattening technique is needed.
In the first part of the thesis, we use a Fabry-Perot laser diode integrated into an erbium-doped fiber amplifier structure. By multi-wavelength injection, dynamic gain flattening and gain clamping can be simultaneously achieved. The experimental results show a good performance, in which the flatness can be less than 2 dB in the range of 1530~1560 nm. As for the second part, we take advantage of the properties of gain clamping and develop a new structure. In this structure, we can monitor the power of each channel in fiber communication networks by scanning the slope of gain curve. From the experimental results, the maximum inaccuracy is about 0.8 dB.
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Xu, Shi-Wen, and 徐世文. "Dynamic characteristic of erbium doped fiber amplifier." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/03063388640545576447.
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Huang, Ying-Jie, and 黃盈傑. "Study of Various Band Erbium-Doped Fiber Amplifier." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/16832718644078607469.
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Chieh, Lin Jen, and 林仁傑. "The Numerical Analysis of Erbium-doped Fiber Amplifier." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/87261068226749720599.
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碩士<br>國立臺灣科技大學<br>電子工程系<br>91<br>In this study, the output performance of different structures EDFA has been analyzed using numerical method. Runge-Kutta method with different boundary conditions is employed to solve simultaneously the governing differential equations of signal, pump and spontaneous emission lights, and thus to analyze signal output performances of EDFA under different input conditions and different configurations.
The EDFA output spectrum is changed when the input parameters including signal and pump wavelength and power are changed. The higher the pump power , the higher output power and gain will result, but when the pump power is higher than what the signal can employ, the power conversion efficiency（PCE）will be decreased. When input signal power is too strong, EDFA’s gain will be decreased, which is called saturation effect. In the pump structure aspect, bidirectional pump structure possesses the highest gain and output power which is 32dB and 15.8mW, but it contains an additional pump source and an additional WDM coupler than backward forward pump structure, which gains and output powers are 30.5dB, 29dB and 11mW, 9.2mW. Finally, fiber bragg grating（FBG）, long period fiber grating（LPFG）and phase shift LPFG are used to analyze the flattening of EDFA gain spectrum, their flattening gain, fluctuant gains and bandwidths are 25dB, 30dB, 30dB and 0.29dB, 1.26dB,1.26dB and 31nm, 27nm, 28nm, respectively.
A good agreement has been found in comparing our numerical results with reports of previous studies, which confirms the correctness of our method and program.
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Wang, Je Min, and 汪哲敏. "Optimization for Hybrid System of Erbium Doped Fiber Amplifier and Fiber Raman Amplifier." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/24432971103604472637.
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碩士<br>國立清華大學<br>光電工程研究所<br>103<br>We intend to produce a fiber laser amplifier by constructing a hybrid system of Erbium doped fiber amplifier and fiber Raman amplifier, to obtain the effect of gain flattening. And we try to optimize the gain of the signal laser by adjusting the length and location of Erbium doped fiber. Comparing to those fiber amplifiers which only use Erbium doped fiber or which only use fiber Raman amplifier, this hybrid system has some unique advantages.
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Chen, Chia-Chu, and 陳嘉駒. "Polarization Mode Dispersion Compensation of Erbium-Doped Fiber Amplifier." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/05530138509978095084.
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碩士<br>國立交通大學<br>光電工程所<br>90<br>Polarization mode dispersion (PMD) compensation becomes more and more important because of the demands for high bit rate in fiber transmission systems. So in this thesis, we use a Faraday rotator mirror and circulator to construct a double pass erbium-doped fiber amplifier (EDFA) for PMD compensation. We will demonstrate the ability that our structure can reduce the PMD values to near zero. The polarization dependent gain (PDG) is also discussed and we can reduce this effect to half of the conventional EDFA’s value.
Beside the polarization effects, we will also show the signal gain and noise figure of our double pass EDFA. This structure can achieve higher gain than conventional one pass EDFA and the noise figure is around 5dB.
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Chen, Yong Guang, and 陳永光. "System and network applications of erbium-doped fiber amplifier." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/61670068681882154330.
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Liao, Hsieh-Hung, and 廖協虹. "Study of (C+L)-band Erbium-doped Fiber Amplifier." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/47284755775226963074.
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碩士<br>國立臺灣科技大學<br>電子工程系<br>92<br>This thesis is focused on (C+L)-band erbium-doped fiber amplifier (EDFA). The optical configuration C- and L-band are in parallel scheme. For the part of C-band amplifier, the 980 nm pumping source is in the forward-pump scheme with 180mW power. Erbium-doped fiber (EDF) has a peak absorption coefficient of 17.66dB/m at 1530nm. The optimum length of EDF has been demonstrated after experimented is 5m. For the L-band amplifier, the optimal configuration of L-band uses two-stage cascading with 980nm and 1480nm pumping. The C- and L-band EDFA have combined by C/L-band WDM coupler. The gain equalization issues, a sixteen-channel wavelength division multiplexing (WDM) sources, with —10dBm per channel and 5 nm channel spacing from 1530 and 1605nm, are lunched into the EDFA. An optimized gain variation less than ±1.43 dB is achieved without any flatness fiber component to modify the gain spectrum shape.
We also apply the EDFA in compensating the loss of fiber module and lightwave system. The first one is the integration of the EDFA in an optical add/drop multiplexer (OADM). The single 980 nm pumping source with 50mW power is pumping shared to two pieces of EDFs for optical amplification. The net gain at the output port is 10.1 dB. The second one is used EDFA for power compensation in a bi-directional transmission system. The power penalty of only 0.045dB is observed in this bi-directional transmission system. The system performance confirms the feasibility of the bi-directional transmission system.
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Pai, Chi-Che, and 白奇哲. "Polarization Mode Dispersion of an Erbium-Doped Fiber Amplifier." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/55007740484250976594.
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碩士<br>國立臺灣科技大學<br>光電工程研究所<br>104<br>In this paper, a mathematical model is proposed to evaluate the polarization mode dispersion (PMD) of erbium-doped fiber amplifier based on Mueller matrix. A Erbium-doped fiber amplifier (EDFA) modulated by a pumping source cause the energy gap of amplified spontaneous emission (ASE) getting the characteristic of modulating signal.
The modulated amplified spontaneous emission can be the polarization mode dispersion monitoring system. All the methods we used are based on frequency domain. It is better than the approaches based on time domain, due to the fact that the experimental structure is convenient. The differential group delay (DGD) we calculated by Jones matrix eigenvalue method can be proved by the Poincare’ arc method using Poincare’ arc method.
We fixed the polarization state of a tunable laser at 60 degree of linear polarization to incident in EDFA at the range of wavelength 1542nm-1566nm. The data we got from the experiment can be verified the polarization mode dispersion we measured.
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Chang, Deng Keng, and 張登貴. "Improvement Design of the Distributed Erbium-doped Fiber Amplifier." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/74142675562803152792.
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Su, Ling-Hui, and 蘇鈴惠. "Gain-Clamping Technique of L-Band Erbium-Doped Fiber Amplifier." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/01496778470443517556.
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碩士<br>國立中山大學<br>光電工程研究所<br>89<br>Recently, the long-wavelength band (L-band, 1570-1600 nm) erbium-doped fiber amplifiers (EDFAs) has received much attention. By combining the gain bandwidth of a conventional C-band EDFA and L-band EDFA in parallel, the available gain bandwidth can be increased by a factor of two. The change in the input power and the number of channels leads to the variation of the channel output power, which, in turn, changes the gain spectrum and flatness. To cope with this problem, the gain-clamped (GC) technique has been proposed. The gain-clamping techniques have been extensively explored for C-band EDFAs, but fewer for L-band EDFAs.
In this thesis, we experimentally investigate an optically gain-clamped L-band EDFA with different lasing lights (1568 nm and 1600 nm) and different loop attenuation. The characteristics of such L-band GC-EDFAs measured in a simulated add-drop operation are examined and compared. We find that the 1568-nm lasing light with 0-dB loop attenuation is the better selection for L-band GC-EDFA to offer good channel gain (19.4 dB) and satisfied noise figure characteristics. Compared to the gain variation observed for GC-EDFA with an open loop, the GC-EDFA was effective in reducing the total gain variation of 17 dB and increasing the dynamic range of 25 dB.
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Ting-Tsan, Huang. "Study of Gain Flattened and Clamped Erbium-Doped Fiber Amplifier and Fiber Laser." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0009-2007200622454000.
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Huang, Ting-Tsan, and 黃珽瓚. "Study of Gain Flattened and Clamped Erbium-Doped Fiber Amplifier and Fiber Laser." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/62534232916628968779.
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碩士<br>元智大學<br>光電工程研究所<br>94<br>In the first part of the thesis, we propose and investigate experimentally a gain-flattened and gain-clamped two-stage erbium-based fiber amplifier (EBFA) module. The maximum gain variations of ±0.8 and ±1.8 dB are observed in an operating range of 1530 to 1564 nm, when the input signal powers are 15 and ?{40 dBm, respectively. In a 25 dB dynamics input signal power range from ?{15 to ?{40 dBm over the operating range, the maximal gain difference of 2.7 dB is also retrieved at 1556 nm for the GF and GC erbium amplifier.
In the second part of the thesis, We propose and demonstrate a tunable and stable single-longitudinal-mode (SLM) erbium fiber laser with a passive triple-ring cavity structure in S-band operation. The proposed laser is fundamentally structured by using three different lengths of ring cavities, which serve as the mode filters. When a mode-restricting intracavity fiber Fabry-Perot tunable filter (FFP-TF) is combined, the proposed resonator can guarantee a tunable and stable SLM laser oscillation.
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Tsuo, Hung-Yung, and 卓鴻揚. "Fabrication and Analysis of Thermal Effect of Erbium Doped Fiber Amplifier." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/89192604262099706464.
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碩士<br>北台科學技術學院<br>機電整合研究所<br>93<br>The thesis is to study the circuits of Erbium Doped Fiber Amplifier (EDFA) and investigate the optical spectrum change of Erbium-Doped Superfluorescent Fiber Source (Er-doped SFS) in high temperature.
In the experiment, the pump power of 980nm wavelength pump laser structured by single-pass backward (SPB) SFS effects only a little on the average wavelength of SFS. The drive and temperature control circuits of the 980nm wavelength pump laser were made by myself. It needs considerate the supply of temperature and electric current steadily under the normal temperature. When the Er-doped SFS is coupled with 980nm wavelength pump laser, only the Er-doped fiber is put into the programmable temperature chamber, and than the temperature of the chamber is increased from 30℃ to 450℃ to study the changes of mean-wavelength and line-width.
From observing the change of average wavelength and line-width of SFS, a linear variation with increasing temperature, the average wavelength shift to the long wavelength, and the wider line-band can be found. Therefore, if the average wavelength of the ASE Light Source is designed to be a linear property and shift to the longer wavelength versus to temperature increase, its gain is required to be saturated by regulating.
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Wang, Chih Jhong, and 王志中. "High gain & Low noise Broad Band Erbium Doped Fiber Amplifier." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/16811031535309204923.
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Tsai, Po-Yu, and 蔡博宇. "Gain Clamping Characteristic of C+L Broadband Erbium Doped Fiber Amplifier." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/7np8ym.
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碩士<br>國立東華大學<br>電機工程學系<br>102<br>This paper was titled “Gain Clamping Characteristic of C+L Broadband Erbium Doped Fiber Amplifier.” In this study, we first measured the gain with C+L broadband completed. The experimental setup used 5.5m erbium doped fiber (EDF) by using C/L coupler to divide C-band one - pass and L-band double - pass. Thus, we could improve the gain for L-band amplification. The pump wavelength and pump power are 980nm and 200mw respectively.
To reach gain clamping, when the C+L broadband EDFA completion was needed. We used Amplified Spontaneous Emission (ASE) to create by the C+L broadband EDFA feedback into the ring cavity. It could produce the clamping laser to reach gain clamping. In the ring cavity, we observe gain clamping variation in different devices to try more structures, single and multi-input signals, input power, fiber Bragg grating(FBG), pumping wavelength, and gain medium to find the best clamp structure.
This experiment proofed that the gain could be clamped with equalization by using ring cavity structure. Therefore, this experiment result showed that the gain clamping range from -5~-25dBm could be reached and the gain peak at the wavelength 1575nm was 19.51dB. Also, the noise figure was 6.14dB. So, we chose 3m EDF, 1480nm 200mW and 1540.355nm for the gain medium, pump parameters and FBG respectively.
We proposed amplifier could offer significant implications as stated above, which can improved C+L broadband amplification and clamping result. The gain and clamping wavelength range was added, it was be increased the transmission capacity and can choose wider range for input power in the use of WDM transmission system is more convenient.
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Chen, Yen-Hsun, and 陳彥勳. "Reflective type broadband Erbium Doped Fiber Amplifier with C/L coupler." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/41866594579395073223.
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碩士<br>國立東華大學<br>電機工程學系<br>101<br>In this paper, we constructed a new EDFA structure to obtain a goal of broadband and gain flatted. First, we measured the characteristic of gain in different length EDFs. Basically, longer EDF could amplify the signals of longer center wavelength. Otherwise, shorter EDF could amplify the signals of shorter center wavelength.
We proposed a EDFA structure with BBFBG. But in this structure, it would generate a lasing by BBFBG and FRM because their operating wavelength was overlapping, and the gain could be decrease by it. So we would change the structure to obtain the high gain and low noise figure.
And we proposed and demonstrated a novel erbium-doped fiber amplifier structure with C/L coupler for broadband and flat gain in this paper. In this structure, we could avoid to produce lasing from FRM and BBFBG. In this optimal pumping configuration, the peak gain 16.21dB and 3dB gain bandwidth is 65nm(1527nm to 1592nm) when input signal power of 0dBm.
Other, we added a 1567.8nm FBG, circulator2 and a 90/10 coupler to produce a cavity, and adjusted appropriate pump power. We can extend a clamping EDFA structure and it can clamp C- and L-band gain at 15 and 17dB when input signal power was -8dBm.
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Lee, Yih-Cherng, and 李義成. "Design and Application of Erbium-Doped Fiber Amplifier in WDM Signals Transmission." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/48271661544360162449.
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碩士<br>國立成功大學<br>電機工程學系<br>85<br>Lightwave transmission system utilizing both WDM technique and Erbium-Doped Fiber Amplifiers (EDFAs) is an attractive choice for communication system design. But there are three major problems of EDFA operating in such a system. The first is EDFA's gain variation in optical fiber network. The second is power difference enlargement among WDM signals in long-haul EDFA cascading transmission system. The final is ASE noises accumulation along EDFAs chain.
In this thesis, we demonstrate several Automatic Gain Control (AGC) methods to stabilize EDFA's gain variation in optical fiber network. We also propose two EDFA gain equalization methods to prevent power difference enlargement in cascaded EDFAs. One is a simple but reasonable method for EDFA length optimization, while the other is an application of unpumped EDF. Unpumped EDF can also be used as a 1530-nm band rejection filter by proper design. It can interrupt the accumulation of 1530-nm band ASE noises. Finally, a concept of identical EDFA is presented for preserving the achievements of individual EDFA design in practical system.
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Huang, Jian-Wen, and 黃建文. "A Study of Gain Clamped and Broad-Band Erbium Doped Fiber Amplifier." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/61897019999211775271.
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Huang, Yu-Jhih, and 黃宇志. "A Study of the Multi-Stage L-Band Erbium-Doped Fiber Amplifier." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/12206381364035808784.
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碩士<br>國立高雄應用科技大學<br>電子與資訊工程研究所碩士班<br>96<br>In the optical fiber communications, the operating wavelength range has been extended from the conventional band (C-band, 1520nm-1560nm) to the long-wavelength band (L-band, 1560nm-1620nm), because of the need in the bandwidth for data transmission. Generally, the L-band erbium-doped fiber amplifier (EDFA) can amplify well the L-band signal, but its pump efficiency is low.
In this thesis, we first simulate and analyze numerically the characteristics of L-band EDFA through MATLAB. It is found that the gain and pump efficiency could be improved by using shorter EDFs. By our results of analysis, we propose a multi-stage L-band EDFA to improve the pump efficiency. Using the EDF of total length 50m and pump source of total power 70mW, our simulation results show that the gain of single-stage EDFA is 2.3dB; the gain of 2-stage EDFA is 15.5dB; and the gain of 5-stage EDFA is 17.9dB. The useful wavelength range can be improved from 12nm for the single-stage EDFA, to 60nm for the 5-stage EDFA.
Then, using the EDF of total length 50m and pump source of total power 70mW, our experimental results show the gain of 5-stage EDFA is 8dB higher than the single-stage EDFA and the useful range can be extended from 19nm for the single-stage EDFA to 40nm for the 5-stage EDFA. A good agreement between our simulations and our experimental results is observed for the multi-stage L-band EDFA.
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Liu, Yi-Lun, and 劉易倫. "A Study of Gain-Enhanced and Gain-Clamped Erbium-Doped Fiber Amplifier." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/04743868576521729037.
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碩士<br>國立高雄第一科技大學<br>光電工程研究所<br>95<br>We first focus on gain-enhanced C-band and L-band erbium-dope fiber amplifier. By adjusting the length of erbium-dope fiber to design the gain-flattened of amplifier. And discuss different structures and pump laser of the amplifier. However, the L-band erbium-dope fiber amplifier has recently been valued highly in the recent years. Adding L-band amplify range of 1570-1610 nm and doing with C-band erbium-dope fiber amplifier could expand the capacity of the WDM system. We choose the best L-band erbium-doped fiber amplifier of the 1480 nm forward pump to configure, then making use of FBG various different parameter to adjust the best clamp result.The simulation results shows that the channel gain is average above 24 dB and noise figure below 5 dB with 32, 24, 16, 8, 4 inputs in the L-band erbium-dope fiber amplifier we design. Good gain-flatness(ΔG＜0.7 dB) is base on the output frequency spectrum between 1574.54-1600.60 nm, and in the left-band, middle-band, and right-band, we have 2.2 dB, 1.3 dB, 0.9 dB three kinds of clamp effects.
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Tsai, Tsung-Li, and 蔡宗歷. "Studies on Dynamic Gain Equalization of WDM Signals in Erbium- Doped Fiber Amplifier." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/43507598992009804294.
Full textAbstract:
碩士<br>國立成功大學<br>電機工程學系<br>86<br>Recently, it is an optimal system configuration to improve
the performance of optical transmission system by applying EDFA(
Erbium-Doped Fiber Amplifier)and WDM(Wavelength Division
Multiplexing) techniques. We can repeat the opticalpower
directly by utilizing EDFA, and have not to make E/O conversion.
WDM is atechnique that can use the wide band fully to upgrade
the channel capacity. Butthere are several problems to overcome
in such a system. One of them is the gainvariation of EDFA due
to the change of optical channels. Besides, in long distance
transmission, how to compensate the variation through a chain of
EDFAis another problem. In this thesis, we design to solve
the gain variation due to the change of the number of optical
channel mainly. First, we review the concept of automatic gain
control mentioned before and some methods to achieve the goal.
After talking about the advantages and disadvantages of these
methods, we introducea new approach and make some comparisons.
This new method has higher compensation performance. We design
several control loops to present ourcompensation methods. In
long distance transmission system, we also apply thismethod to
stabilize the gain variation.
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Lo, Yung-Hsiang, and 羅詠翔. "Investigation of High Gain L-band Erbium Doped Fiber Amplifier with Different Structure." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/4x42w2.
Full textAbstract:
碩士<br>國立東華大學<br>電機工程學系<br>102<br>In this paper, we experimented four different architectures to achieve a goal of high gain and low noise figure with L-band erbium doped fiber amplifier that were in the same medium length and total pump power.
First, we structured a single stage L-band erbium doped fiber amplifier (EDFA) to investigate the gain characteristic. Second, we structured a two-stage L-band EDFA to investigate the gain characteristic. Finally, we used a Faraday rotator mirror (FRM) and an optical circulator to structure two reflective type two-stage L-band EDFAs. The type 1 was that let the second stage of the EDFA double pass. The type 2 was that let the first stage of the EDFA double pass.
And we demonstrated each architecture optimized configuration of pump power. The two-stage L-band EDFA is better than the single-stage L-band EDFA on the aspect of gain, and the gain was improved by 4dB from 1572 nm to 1588 nm. The reflective type two-stage L-band EDFA is better than the two-stage L-band EDFA on the aspect of the gain, and the gain was improved by 5dB from 1588 nm to 1608 nm.
In the architecture of two-stage L-band erbium-doped fiber amplifier, we interchanged the gain medium length without a difference for gain, but the noise figure was improved approximately by 0.6dB. In the architecture of reflective type two-stage L-band EDFA, we interchanged the positions of EDFA without a difference for gain, but the noise figure was improved approximately by 2dB.
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Jih, Wen Jyh, and 紀文智. "The Effective Model of Amplified Spontaneous Emission Noise in Erbium-Doped Fiber Amplifier." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/93912791032088490121.
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Pan, Ta-Kang, and 潘大綱. "Characterization of erbium-doped fiber master oscillator power amplifier for pulsed chaos amplification." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/c8nad3.
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LIU, MING-HONG, and 劉明宏. "Detailed investigation and simulation of IM/DD optical fiber communication system using erbium-doped fiber amplifier." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/56052682487453871434.
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Law, Pi-Cheng, and 羅丕丞. "Applications of Erbium-Doped Fiber Amplifier in Time-Division Multiplexing Fiber-Optic Michelson Interferometric Sensing System." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/55260536753232278053.
Full textAbstract:
碩士<br>國立中山大學<br>光電工程研究所<br>85<br>Fiber-Optic interferometric sensors multiplexing system combine broadband fiber optic communications with fiber-optic sensors of high sensitivity, so it has the advantage of extremely high sensitivity, geometric versatilty of sensing element, immunity to electromagnetic interference (EMI), a large number of sensors, electrically passive, lightweight, wide dynamic range. So far some people have used the compensation technique of unbalanced Michelson interferometer with Faraday rotator mirror (FRM) to solve the problem of polarization-induced signal fading, crosstalk and phase noise.
In this thesis, we apply the 1.55μm DFB diode laser transmitter and erbiumdoped fiber amplifier (EDFA) in the interferometric fiber-optic sensor TDM array system. The utilization of 1.55μm DFB laser source with broader spectral linewidth (1-50 MHz) as a transmitter source not only can reduce the crosstalk between sensors and crosstalk induced by the Rayleigh scattering, but also can relax the stimulated Brillouin scattering effec. Furthermore, it is superior operating transmission at 1.55μm band due to the lower fiber attenuation. Utilization of polarization-insensitive EDFA as a power amplifier located after the external modulator or as an in-line amplifier before the compensation interferometer (Cl) , or as a pre-amplifier located before the optical receiver can increase the transmitted power or improve the receiver sensitivity. In consequence, the number of sensors can be increased greatly, and the practical application of the interferometric fiberoptic sensor array system can be realized.
This experiment study the optimized power amplifier and pre-arnplifier or in-line amplifier for the fiber-optic sensing system. The optically amplified fiber-optic sensing system has five configurations: 1) power amplifier configuration, 2) preamplifier configuration, 3) power amplifier plus pre-amplifier configuration, 4) in-line amplifier configuration, 5) power amplifier plus in-line amplifier configuration etc. We estimated the sensing performance and system size limitation of these configurations from the standpoints of sensitivity, number of sensors, and sensors crosstalk. We conclude that power amplifier plus in-line amplifier configuration is the best one to have the largest number of sensors of 35 sets (the configuration without EDFA only has 2 sets) . It has the similar sensitivity order of 0.209 mrad and similar sensors crosstalk of 42.18dB as the configuration without EDFA. The power amplifier plus pre-amplifier configuration only has the second largest system size of 30 sensor sets, however, higher system sensitivity can be improved by reducing the number of sensor sets, and locating the 1nm optical band-pass filter (OBPF) after the power amplifier to solve the problem of sensors crosstalk. For the in-line amplifier configuration the sensitivity of 0.212 mrad, the sensors of 9 sets, and the sensors crosstalk of 43.12dB can be achieved. These characteristics are enough to apply it to the sensing array system with eight sets of sensors per array. In the near future, for the large-scale-size WDM-TDM fiber-optic sensor-array system will need the power amplifier plus in-line amplifier configuration again. On the contrary, the pre-amplifier configuration has limited benefit due to the smallest system size (4 sensor sets), worse sensitivity (0.745mrad) and higher sensors crosstalk (39.54dB).
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Hung, Shih-Lei, and 洪詩蕾. "Design and Fabrication of High Conversion-Efficiency Flattened L-band Erbium Doped Fiber Amplifier." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/79150967316998327852.
Full textAbstract:
碩士<br>國立中山大學<br>光電工程研究所<br>90<br>In this thesis, we theoretically investigate optimum configurations of high conversion efficiency and gain-flattened L-band (1570-1600 nm) erbium-doped fiber amplifier (EDFA) by employing the 1480 nm and 980 nm bi-directional pumping configuration. The design criterion of L-band EDFA is to achieve highest channel output power while keeping the differential channel gain to be ＜0.7 dB among 32 channels with low channel noise figure of ＜6 dB. The nine L-band EDFA configurations are examined and compared. These configurations considered include the dual-forward, dual-backward, and different bi-directional pumping schemes, each with and without the midway optical isolator. Among all configurations, we find that the pump-pass case in forward-and-backward pumping scheme by employing the 1480 nm pumping wavelength is the best configuration to offer the highest channel output power with good channel gain uniformity and moderate low noise figure. Then we verified the simulation results through experiments. We also theoretically investigate gain-flattened C-band (1530-1560 nm) EDFA. Using L-band and C-band EDFAs in parallel, we can greatly expand the amplification wavelength region.
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Hung, Chi-Yu, and 洪繼宇. "Research of L band Erbium-Doped Fiber Amplifier for Improving the Power Conversion Efficiency." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/59680602660964782487.
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Hung, Hao-Liang, and 洪豪良. "Theoretical and Experimental Analysis of Polarization Mode Dispersion in an Erbium-Doped Fiber Amplifier." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/79093049707960298688.
Full textAbstract:
碩士<br>國立臺灣科技大學<br>電子工程系<br>90<br>A theoretical model is proposed to study the polarization mode dispersion effect in an Erbium-Doped Fiber Amplifier (EDFA). Starting from the three-dimensional Maxwell''s equation to describe the evolution of light inside an EDFA, the concepts of
the electric dipole transition and Kramers-Kronig relationship
are employed to characterize the susceptibility tensor. Analytical expression of the electric field, and hence the Stokes parameters, of light inside the EDFA can be found. the differential group delay (DGD) of light through an EDFA can then properly found. A set of experimental data, which consists
of the Stokes parameters by using wavelength scanning method and the DGD by using Jones Matrix Eigenanalysis (JME) method, is provided to verify the validity of the theoretical model.
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LI, TING-HUNG, and 李定鴻. "The Study of L-band Erbium-Doped Fiber Gain Clamping Amplifier Structure and Best Parameters." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/26190722264341803713.
Full textAbstract:
碩士<br>國立東華大學<br>電機工程學系<br>99<br>In this paper, we set up a ring cavity with a fiber Bragg grating (FBG) or C/L coupler and circulator to construct a L-band erbium-doped fiber gain clamping amplifier (EDFGCA). The performance of EDFGCA is demonstrated by considering the different FBG wavelength, pumping power, single or WDM input signal, and single or two stage structure.
When the input is multi-signal, the best experimental result of single stage structure is to use 1571nm FBG and bi-direction pumping power of 200+200mW, the clamping gain can achieve 10.84dB with gain variation below 0.3dB for input signal power from -20dBm to -5dBm.
When the input signal is single channel, the best experimental result of single stage structure is to use 1561nm FBG and bi-direction pumping power of 200+200mW, the clamping gain can achieve 15.44dB with gain variation below 0.3dB for input signal power from -20dBm to 2dBm. By using bi-direction pumping power of 100+100mW, the clamping gain can achieve 15.36dB with gain variation below 0.3dB for input signal power from -20dBm to -4dBm. Comparing the results of two different pump power, clamping gain is almost the same, but the clamping range is large in the high pumping power case.
By comparing the experimental results of input multi-signal and single-signal, we show that the gain clamped performance is better with bi-direction pump power of 200 +200mW, but the FBG wavelength of best gain-clamped performance is different. This is because the total input signal power is different. The large input power of multi-signal needs a long wavelength FBG of better gain clamping effect.
By Comparing the experimental results of single-stage and two-stage L-band EDFGCA structure with the same total pump power, single-stage gain clamping performance is better than that of two-stage structure, because the second stage of two stage structure can not generate enough clamping lasing power to clamping the input signal of first stage.
Our L-band EDFGCA can operate from 1560~1615nm signal wavelength and covers the entire L-band. The clamped gain can achieve 15.44dB with gain variation below 0.3dB for input signal power from -20dBm to 2dBm. The proposed L-band EDFGCA can be used to amplify the entire L-band signal, and provide a stable gain without variation.
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Wang, Chun-Wei, and 王駿瑋. "Hybrid Raman/Erbium-Doped Fiber Amplifier for High Speed OFDM Long-Reach Passive Optical Network System." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/q7qr94.
Full textAbstract:
碩士<br>國立交通大學<br>光電工程研究所<br>106<br>Since the ever-growing of the technology and public’s reliance of social media, the needs of data transmission is getting larger nowadays. Passive optical network (PON) is a promising way to achieve the requirement. In the standard of next-generation PON (NGPON2) by Full Service Access Network, the fiber distance is 20-km to 1000-km, and provides 40-Gbps network transmission capacity to support 1-Gbps data rate per optical network unit (ONU). OFDM LR-PON becomes one of the most promising candidates for the development of low-cost, high capacity access networks with wide coverage.
The fiber Raman amplifier has two merits. One is the low noise characters and the other is the arbitrary spectral gain band. So, it plays an important role in optical communication system. In this paper, we employ hybrid Raman amplifier and nonlinear distortion compensation techniques. Then, we demonstrate a high speed and high capacity OFDM LR-PON system.