Optimization Tool for Erbium Doped Fibre Amplifiers Electrical and Computer Engineering

109 Pages·2016·2.94 MB·English

by  Pedro Antunes

Optimization Tool for Erbium Doped Fibre Amplifiers

Pedro Tavares Antunes

Thesis to obtain the Master Science Degree in
Electrical and Computer Engineering

Supervisors: Prof. Paulo Sérgio de Brito André
Eng. Carlo Marques
Dr. Paola Frascella

Examination Committee
Chairperson: Prof. José Eduardo Charters Ribeiro da Cunha Sanguino
Supervisor: Prof. Paulo Sérgio de Brito André
Members of the Committee: Prof. Mário José Neves de Lima

May, 2016
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To my family

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Acknowledgments

Firstly, I would like to express my sincere gratitude to Prof. Paulo André, for selecting me for this
dissertation and grating me the opportunity to develop this work in a business environment.
I would like to thank Coriant for providing me with a working space in their facilities in Alfragide (Lisbon),
where most of the work took place. I would also like to leave a word of appreciation to my co-supervisors
within the company, Eng. Carlo Marques and Dr. Paola Frascella, for their constant support, patience
and knowledge which was instrumental to overcome some of the challenges I faced throughout this
dissertation. Thank you for steering me in the right direction throughout this process.
Special thanks to my friends and colleagues, and most importantly to my family, particularly my parents
and brother, for providing me with the possibility to be where I am today. Without your love,
encouragement, advice and endless support, none of this would have been possible.

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Resumo

Os amplificadores de Fibra Dopada com Érbio (EDFA) - caracterizados pelo elevado ganho e largura
de banda, baixas perdas intrínsecas e rápidos tempos de reposta - emergiram nas últimas décadas
como componentes essências de comunicações óticas com multiplexagem espectral (WDM). A
transição progressiva das redes atuais para redes puramente óticas de alta capacidade, aumentou a
complexidade dos elementos de rede, influenciando o custo global dos sistemas. Consequentemente,
a otimização de elementos ativos tornou-se um processo crucial em sistemas WDM modernos. O
objetivo desta dissertação é propor uma ferramenta de otimização eficaz para o desenho de EDFAs.
As principais contribuições desta dissertação incluem: i) teoria e criação de modelos representativos
da Fibra Dopada com Érbio e dos dispositivos passivos que compõem a arquitetura dos EDFAs, ii)
descrição das características do amplificador e a sua relação com diferentes componentes, topologias
e configurações de bombeamento, iii) avaliação dos principais parâmetros de desempenho, iv)
desenvolvimento de um simulador eficiente para EDFA, englobando várias topologias e opções de
bombeamento, v) elaboração de um algoritmo heurístico para testar e avaliar vários EDFAs, de acordo
com um conjunto de requisitos de rede, de modo a selecionar e otimizar a mais solução de menor custo.
Os resultados obtidos demonstram que a ferramenta proposta é capaz de determinar uma solução
otimizada de EDFA para diversas situações, indicando com precisão os parâmetros de desenho que
garantem os requisitos de rede predefinidos. A utilização desta ferramenta reduz a quantidade de testes
experimentais a efetuar para encontrar uma solução ótima, economizando tempo e dinheiro.

Palavras-chave — Comunicações óticas, WDM, amplificador ótico, EDFA, técnicas de otimização.
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Abstract

Erbium Doped Fibre Amplifiers (EDFA), featuring high gain over a large bandwidth, low intrinsic losses
and long fluorescence times, have emerged over the past decades as key enabling components in WDM
systems. The progressive transition towards high capacity, all-optical networks has increased the
complexity of each network element, thus impacting the overall cost of the systems. Therefore, optimum
design of network active elements became a crucial part of modern WDM systems. The goal of this
dissertation is to propose an effective optimization tool for steady-state EDFA design.
The main contributions of this dissertation include: i) theory and modelling of Erbium Doped Fibre and
passive devices that compose EDFA´s architecture, ii) description on EDFA´s characteristics and their
relation with amplifier’s components, topologies and pumping configurations, iii) assessment of key
design parameters, iv) development of an efficient simulator for EDFA, supporting several topologies
and pumping configurations, v) construction of a heuristic algorithm for testing and evaluating several
EDFA topologies according to a set of network requirements, in order to select and optimize the most
cost-effective solution.
The obtained results show that the proposed optimization tool is able to deliver an optimized EDFA
solution for all the three case studies, indicating an accurate determination of design parameters in order
to meet pre-establish network requirements. Additionally, employing the proposed tool reduces the
amount of experimental tests necessary to find an optimum solution, thereby saving both time and
money.

Keywords — Optical Communications, WDM, Optical Amplifier, EDFA, optimization techniques.
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