Optical fiber transmission systems for in-door next generation broadband access network.

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London.This thesis investigates the generation and radio-over-fibre (RoF) transport of unlicensed 60 GHz millimetre-wave (mm-wave) frequency band. The investigated benefits of transmission schemes applicable for the mm-wave generation include optical carrier suppression (OCS), optical frequency multiplication (OFM) and remote heterodyne detection (RHD). For the in-door cabling of the mm-wave transmission, a low-cost polymer optical fibre (POF) along with bend-insensitive single mode fibre (BI-SMF) has been investigated for short-range networks. Transporting mm-wave generated signals over POF and BI-SMF cables based on OCS scheme showed results with the highest spectral efficiency and least inter-symbol interference over a 2.5 Gbit/s data delivery. Based on this thesis analysis, OCS simulation of POF showed the most reliable power penalty performance and receiver sensitivity at 30-m whilst the BI-SMF fiber produced equal observations at 150-m and more. In observing the free space links of delivering the RoF signal, the attenuation on the received signal power for both POF and BI-SMF was insignificant but expected, as the simulation assumed complete and total collimation of the light beams onto the aperture of the photodetector. OCS scheme for mm-wave generation and transport was explored based on the cost effectiveness of using one external modulator compared to other generation schemes that utilised more than one external modulator. OFM scheme was simulated to transport LTE and Wi-Fi signals along with 60 GHz RF band through both SMF and MMF-POF/BI-SMF cables. OFM transport scheme produced the highest attenuation on LTE, Wi-Fi and mm-wave signals carrying 100 Mbit/s data as simulated POF lengths increased. The best performance POF length was observed at 10-m. The application of offset launch technique at the coupling of SMF and POF showed insignificant improvement on signal bandwidth. The free space OFM transmission also demonstrated negligible change to the received signal power. This reinforces the attributes of deploying OWC system in an in-door environment. In other investigation, the simulated successful delivery of mm-wave signal using RHD scheme modulated and transported 10 Gbit/s data signal over POF and BI-SMF cables. Additional observed unrecorded result also showed BI-SMF cable maintained a 2% reduction of received power for 450-m fiber cable from 150-m. The attributes to RHD includes its low operating power system application and delivery of localised 60 GHz signal for uplink RoF transmission. The conceptualised design of Gigabit data delivery for indoor customer applications either through POF or BI-SMF cable, transporting various wireless channels has been presented in this thesis for the design of a robust next generation Broadband access network to reinforce the fiber-inside-the-home (FiTH) deployment

Design of optical fiber sensors and interrogation schemes

[ES] Las fibras ópticas son dispositivos muy utilizados en el campo de las telecomunicaciones desde su descubrimiento. En las últimas décadas, las fibras ópticas comenzaron a utilizarse como sensores fotónicos. Los primeros trabajos se centraron en la medición de unas dimensiones físicas en un punto específico. Posteriormente, surgió la posibilidad de medir las propiedades de la fibra óptica en diferentes puntos a lo largo de la fibra. Este tipo de sensores se definen como sensores distribuidos. Los componentes optoelectrónicos fueron desarrollados e investigados para telecomunicaciones. Los avances en las telecomunicaciones hicieron posible el desarrollo de sistemas de interrogación para sensores de fibra óptica, creciendo en paralelo con los avances de las telecomunicaciones. Se desarrollaron sistemas de interrogación de fibra óptica que permiten el uso de una única fibra óptica monomodo estándar como sensor que puede monitorear decenas de miles de puntos de detección al mismo tiempo. Los métodos que extraen la información de detección de la señal reflejada en la fibra óptica son los más empleados debido a la facilidad de acceso al sensor y la flexibilidad de estos sistemas. Los más estudiados son la reflectometría en dominios de tiempo y frecuencia. La reflectometría óptica en el dominio del tiempo (OTDR) fue la primera técnica utilizada para detectar la posición de los fallos en las redes de comunica-ción de fibra óptica. El OTDR sensible a la fase hizo posible detectar la elongación y la temperatura en una posición específica. Paralelamente, los gratings de Bragg (FBG) se convirtieron en los dispositivos más utilizados para implementar sensores en fibra óptica discretos. Se desarrollaron técnicas de multiplexación para realizar la detección en múltiples puntos utilizando FGBs. La reflectometría realizada interrogando arrays de FBG débiles demuestra que mejora el rendimiento del sistema en comparación al uso de una fibra monomodo. Los sistemas de interrogatorio actuales tienen algunos inconvenientes. Algunos de ellos son velocidad de interrogatorio limitada, grandes dimensiones y alto costo. En esta tesis doctoral se desarrollaron nuevos sistemas de interrogación y sensores de fibra óptica para superar algunos de estos inconvenientes. Los sensores de fibra óptica de plástico demuestran ser una plataforma innovadora para desarrollar nuevos sensores y sistemas de interrogación de bajo costo y fáciles de implementar para fibras de plástico comerciales. Se investigó la reflectometría en el dominio del tiempo y las técnicas fotónicas de microondas para la interrogación de una matriz de rejillas débiles que permitieron simplificar el sistema de interrogación para la detección de temperatura y vibración.[CA] Les fibres òptiques són dispositius molt utilitzats en el camp de les telecomunica-cions des del seu descobriment. En les últimes dècades, les fibres òptiques van començar a utilitzar-se com a sensors fotònics. Els primers treballs es van centrar en el mesurament d'unes dimensions físiques en un punt específic. Posteriorment, va sorgir la possibilitat de mesurar les propietats de la fibra òptica en diferents punts al llarg de la fibra. Aquest tipus de sensors es defineixen com a sensors distribüits. Els components optoelectrònics van ser desenvolupats i investigats per a telecomunicacions. Els avanços en les telecomunicacions van fer possi-ble el desenvolupament de sistemes d'interrogació per a sensors de fibra òptica, creixent en paral·lel amb els avanços de les telecomunicacions. Es van desenvolupar sistemes d'interrogació de fibra òptica que permeten l'ús d'una única fibra òptica monomodo estàndard com a sensor que pot monitorar desenes de milers de punts de detecció al mateix temps. Els mètodes que extreuen la informació de detecció del senyal reflectit en la fibra òptica són els més utilitzats a causa de la facilitat d'accés al sensor i la flexibilitat d'aquests sistemes. Els més estudiats són la reflectometría en dominis de temps i freqüència. La reflectometría òptica en el domini del temps (OTDR) va ser la primera tècnica utilitzada per a detectar la posició de les fallades en les xarxes de comunicació de fibra òptica. El OTDR sensible a la fase va fer possible detectar l'elongació i la temperatura en una posició específica. Paral·lelament, els gratings de Bragg (FBG) es van convertir en els dispositius més utilitzats per a implementar sensors en fibra òptica discrets. Es van desenvolupar tècniques de multiplexació per a realitzar la detecció en múltiples punts utilitzant FGBs. La reflectometría realitzada interrogant arrays de FBG febles demostra que millora el rendiment del sistema en comparació a l'ús d'una fibra monomodo. Els sistemes d'interrogatori actuals tenen alguns inconvenients. Alguns d'ells són velocitat d'interrogatori limitada, voluminositat i alt cost. En aquesta tesi doctoral es van desenvolupar nous sistemes d'interrogació i sensors de fibra òptica per a superar alguns d'aquests inconvenients. Els sensors de fibra òptica de plàstic demostren ser una plataforma innovadora per a desenvolupar nous sensors i siste-mes d'interrogació de baix cost i fàcils d'implementar per a fibres de plàstic comercials. Es va investigar la reflectometría en el domini del temps i les tècniques fotòniques de microones per a la interrogació d'una matriu de reixetes febles que van permetre simplificar el sistema d'interrogació per a la detecció de temperatura i vibració.[EN] Optical fibers are devices largely used in telecommunication field since their discovery. In the last decades, optical fibers started to be used as photonic sensors. The first works were focused on the measurement of physical dimensions to a specific point. Afterward, emerged the possibility to measure the optical fiber properties at different locations along the fiber. These kinds of sensors are defined as distributed sensors. The optoelectronic components were developed and investigated for telecommunications. The progress in telecommunication made possible the development of optical fiber sensors interrogation systems, growing in parallel with the advances of telecommunications. Optical fiber interrogation systems were developed to use a single standard monomode optical fiber as a sensor that can monitor tens of thousands of sensing points at the same time. The methods that extract the sensing information from the backscattered signal in the optical fiber are widely employed because of the easiness of access to the sensor element and the flexibility of these systems. The most studied are the reflectometry in time and frequency domains. The optical time domain reflectometry (OTDR) was the first technique used to detect the position of the failures in the optical fiber communication networks. Using phase sensitive OTDR it is possible to sense strain and temperature at a specific position. In parallel, fiber Bragg gratings (FBGs) became the most widely used devices to implement discrete optical fiber sensors. Multiplexing techniques were developed to perform multi points sensing using these gratings. The reflectometry performed interrogating weak FBGs arrays demonstrate to improve the performance of the system employing a single mode fiber. The interrogation systems nowadays have some drawbacks. Some of them are limited speed of interrogation, bulkiness, and high cost. New interrogation systems and optical fiber sensors were developed in this doctoral thesis to overcome some of these drawbacks. Plastic optical fiber sensors demonstrate to be an innovative platform to develop both new sensors and low cost, easy to implement interrogation systems for commercial plastic fibers. Reflectometry in time domain and microwave photonic techniques were investigated for the interrogation of weak gratings array allowed to simplify the interrogation system for the sensing of temperature and vibration.I would like to greatly thank the European Union’s Horizon 2020 Research and Innovation Program that funded the research described in this thesis under the Marie Sklodowska-Curie Action Grant Agreement 722509.Sartiano, D. (2021). Design of optical fiber sensors and interrogation schemes [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/161357TESI

Power system applications of fiber optics

Power system applications of optical systems, primarily using fiber optics, are reviewed. The first section reviews fibers as components of communication systems. The second section deals with fiber sensors for power systems, reviewing the many ways light sources and fibers can be combined to make measurements. Methods of measuring electric field gradient are discussed. Optical data processing is the subject of the third section, which begins by reviewing some widely different examples and concludes by outlining some potential applications in power systems: fault location in transformers, optical switching for light fired thyristors and fault detection based on the inherent symmetry of most power apparatus. The fourth and final section is concerned with using optical fibers to transmit power to electric equipment in a high voltage situation, potentially replacing expensive high voltage low power transformers. JPL has designed small photodiodes specifically for this purpose, and fabricated and tested several samples. This work is described

Comunicações avançadas com fibra óptica plástica

Nowadays, fiber to the Home/Curb/Building/Cabinet (FTTx) services that interconnect homes with a standard glass optical fiber cables to the core/access optical networks have brought the optical fiber at the doorsteps of our homes. However, the last few miles in home access network is still based on the limited bandwidth electronic component which supports by the cooper wires e.g. Cat-5, 6. The rapid growth of personal smart/mobile electronic devices with new developments such as video on demand, High Definition (HD) and three-Dimension (3D) television (TV), cloud computing, video conferences, etc. has been proposed new challenges for the next generation high bandwidth demand required for subscribers in home access network. In order to meet the more demanding expectations of the end user with new developments, it is necessary to improve the physical infrastructure of the existing in home networks in order to obtain the best ratio between quality of service and price of implementation. Plastic optical fibers (POFs) are point out as a promising transmission medium for short-range communication in compare to the “classic” single/multimode glass optical fibers and current cooper wire technology developments. The main advantages of POF are its easy to install, easy splicing and the possibility of using low cost optical transceivers, capability of being robust, and immunity to electromagnetic noise interference. However, the benefits of large-core POFs come at the expense of a less bandwidth and a higher attenuation than silica-based solution. The main objective of this doctoral dissertation is to explore the possibilities and develop low cost, short reach, high data rate POF-links for in home networks applications. This thesis investigates the use of multilevel modulation in particular, pulse amplitude modulation (PAM in combination of the receiver equalizer in order to overcome the bandwidth limitations of the graded index POFs. The possibility of the using multiple channels over a single fiber to increase the capacity of POF systems using commercially available multimode components is also analyzed in this dissertation. Moreover, a low cost Digitised radio signal over plastic fiber system is proposed and evaluated to deliver digital baseband data for wireline and wireless users in home access network. The deployment will be specified in terms of performance, maximum rates and any degradation that might appear in the network. Furthermore, the possibilities of the microstructured fibers in telecommunication application will be studied with main emphasis on their structural design. The photonic crystal fibers made of different highly nonlinear materials with different structures are optimized to achieve ultra-flat dispersion, high nonlinearity and low confinement loss over a broad range of wavelengths in the perspective of their usage in telecommunication applications.Hoje em dia, a possibilidade de a fibra óptica até casa (FTTH) para a transmissão simultânea de diferentes serviços como internet, telefone, televisão digital é uma realidade. No entanto, para satisfazer as expectativas mais exigentes do usuário final com novos desenvolvimentos, tais como vídeo sob demanda, de alta definição (HD) e tridimensional (3D) de televisão (TV), computação em nuvem, vídeo conferências, etc., é necessário melhorar a infra-estrutura física da existente em redes domésticas, a fim de obter a melhor relação entre a qualidade do serviço e preço de implementação. Fibra óptica de plástico (POF) é considerada um meio de transmissão promissor para comunicações de curto alcance, queando comparadas com a clássica fibra óptica de silica (tanto monomodo como multimodo) e com as tecnologias atuais baseadas em fio de cobre. As principais vantagens da POF encontramse na sua facilidade de instalação e conecção, possibilidade de uso de fontes e detectores de baixo custo, robustez e imunidade electromagnética. No entanto, o uso da POF de elevado diâmetro têm também desvantagens uma vez que esta oferece uma menor largura de banda e uma atenuação superior à fibra de sílica convêncional. Esta dissertação de doutoramento tem como principal objetivo explorar as possibilidades de desemvolvimento de componentes de baixo custo baseados em POF para redes de curto alcance, com alta taxa de transmisssão de dados. Esta tese investiga a utilização de vários formatos de modulação combinados com equalizador e receptor, de maneira a superar as limitações de largura de banda em sistemas de comunicação óptica de curto alcance. Em particular, a modulação em amplitude de impulso (PAM) é proposta e investigada a fim de aumentar a capacidade de tais sistemas. Além disso, a possibilidade de usar múltiplos canais, utilizando uma única fibra óptica, também conhecido por multiplexagem por divisão de comprimento de onda (WDM), será analisada neste trabalho. A viabilidade das tecnologias de redes de acesso tanto a nível individual como em sistemas WDM serão analisadas usando componentes multimodo disponíveis comercialmente. A implementação será especificada em termos de desempenho tanto a nível da taxas máximas de transmissão, bem como na degradação do sinal que possa ocorrer na rede. No capitulo 5 desta dissertação é apresentado sistema de radio através de fibra. Este tipo de sistemas permite a simplificação das estações base providenciando também uma elevada manutenção de custos. O principal objectivo deste estudo prende-se com a investigação do impacto da amostragem na preformance de digitalização de rádio através de fibra e também como a introdução de fibra óptica de plástico pode afetar o sistema. Além disso, a possibilidade da aplicação de fibras óticas microestruturadas em redes de telecomunicações serão estudadas com ênfase principal na sua concepção estrutural. As fibras de cristal fotônico feitas de diferentes materiais altamente não-lineares com diferentes estruturas serão otimizadas a fim de alcançar uma dispersão ultra-plana, elevada não linearidade e baixa perda de confinamento em uma vasta gama espectral, na perspectiva de seu uso em aplicações de telecomunicações.Programa Doutoral em Engenharia Eletrotécnic

Aspectos de interconectividade dos moduladores de polímero

Orientador: Hugo Enrique Hernández-FigueroaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: As interconexões ópticas e elétricas são de grande interese na area de encapsulamento de circuitos integrados híbridos fotônicos. Baixas perdas e banda larga são necessárias para o desenvolvimento de novas tecnologías na área. Nesta tese apresentan-se as seguintes contribuições originais: uma metodologia do modelamento de interconexões elétricas em encapsulamento de moduladores de polímero eletro-óptico, um dispositivo óptico compacto de banda larga para interconectar a plataforma de silício sobre isolante com a plataforma de filmes finos de polímero sobre silícioAbstract: Electrical and optical interconnects are of great interest for photonic integrated circuits with hybrid platforms. Low loss and wide band are essential for the development of new technologies in this area. In this thesis, we present the following original contributions: a methodology for modeling electrical ceramic interconnects inside an electrooptic polymer packaging, and a compact low-loss optical interconnect for the silicon-on-insulator platform to the thin-film polymer on silicon platformDoutoradoTelecomunicações e TelemáticaDoutor em Engenharia Elétrica07/2014-36CAPE