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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Širokopásmová FTTx přípojka na architektuře WDM - PON / Wide-band FTTx Networks Terminal in WDM - PON architecture

Bobkovič, Peter January 2010 (has links)
This masters thesis is focusing on the issue of passive optic access networks. It is dealing with the limiting factors for broadband connections, especially attenuation of fibre optics and dispersion. It is also dealing with most commonly used standards of passive optic networks. It clarifies the issue of wavelength-division multiplexing, its advantages and disadvantages, used standards, various types of components for the WDM-networks, their characteristics, application etc. In the practical part of the work you can find the measuring and diagnostics of the passive optic network EPON. It contains measuring by the direct method OLTS, measuring by the Pon Power Meter and optic reflectometer OTDR. At the end I am dealing with the measuring of splitter in the rate of 1:16.
2

Možnosti zvýšení propustnosti optovláknové průmyslové sítě / Possibilities of increasing the throughput of optical fiber industrial networks

Čičmanský, Tomáš January 2015 (has links)
Diploma thesis deals with problems of industrial networks using optical fiber as the main transmission lines. The task of the diploma work is to study and summarize the issues of industrial networks as well as the ways to increase their transmission capacity. In telecommunications and computer networks are generally used multiplexes, thanks to which we are able to achieve the desired transmission capacity. Consequently, the following work deals with the selection of the adequate solutions using described multiplexes as well as other transmission methods. The aim of the diploma work is to compare various renovation techniques of an old industrial network. Using this network as an example the work should demonstrate the individual problems and their solutions while considering different types of methods used. Based on the price, the performance and the difficulty to install other devices and transmission media we are able to select the appropriate solution for optical link.
3

Desenvolvimento de ger?ncia SNMP para dispositivos de redes totalmente ?pticas / Development of SNMP management for all network optical devices

Schimidt, Carlos Roberto 08 February 2007 (has links)
Made available in DSpace on 2016-04-04T18:31:17Z (GMT). No. of bitstreams: 1 Carlos Roberto Schimidt.pdf: 1673709 bytes, checksum: bfff1e1a4d903d3af1ffd35db6413138 (MD5) Previous issue date: 2007-02-08 / Optical wavelength converters (OWC) are devices that can reduce congestion and improve the efficiency of the next generation of wavelength division multiplexing (WDM) optical networks. Currently, our research group is developing a prototype of this converter in the Kyatera Project funded by Funda??o de Amparo ? Pesquisa do Estado de S?o Paulo (FAPESP). In this perspective, the objective of this work was to implement an open source software to dynamically manage the wavelength converter prototype in an all optical network. This task was performed in two phases. In the first one, the Telecommunications Management Network (TMN) functionalities were utilized to define the device parameters that should be managed. After this, a management information base (MIB) was structured for the OWC. In the second phase, a SNMP agent was developed and implemented in order to allow the communication between network management and the OWC MIB. Both software programs were tested and worked as expected. The software programs could also be utilized in the communication between a central management and optical nodes that do not perform wavelength conversions or after some adjustments, to manage other all-optical devices. Therefore, this effort may contribute with other research groups or companies that need to evaluate new optical network technologies, such as routing wavelength assignment algorithms and the monitoring of signal quality. For those interested, an appendix fully describes the procedures for managing new devices. / Conversores ?pticos de comprimento de onda s?o equipamentos que podem reduzir o congestionamento e aumentar a efici?ncia da pr?xima gera??o de redes ?pticas com multiplexa??o por divis?o em comprimentos de onda (wavelength division multiplexing, WDM). Atualmente, nosso grupo de pesquisas est? desenvolvendo um prot?tipo deste conversor dentro do Projeto KyaTera promovido pela Funda??o de Amparo ? Pesquisa do Estado de S?o Paulo (FAPESP). Neste contexto, o objetivo deste trabalho foi o de implementar um software de c?digo aberto capaz de gerenciar, de maneira din?mica, a opera??o do conversor em uma rede totalmente ?ptica. Para isso, o trabalho foi dividido em duas etapas. Na primeira, as fun??es de gerenciamento do modelo Telecommunications Management Network (TMN) foram utilizadas para definir os par?metros de gerenciamento do equipamento. A partir destas defini??es, estruturou-se e implementou-se uma Management Information Base (MIB) para o referido equipamento. A segunda etapa consistiu em desenvolver e implementar um agente Simple Network Management Protocol (SNMP) capaz de realizar a comunica??o entre a ger?ncia de redes e a MIB do equipamento conversor. Ambos os softwares foram testados e funcionaram de acordo com o esperado. O software desenvolvido tamb?m pode ser utilizado para realizar a comunica??o entre uma ger?ncia centralizada e n?s ?pticos que n?o fa?am a convers?o de comprimentos de onda ou, mediante pequenas adapta??es, pode ser usado para gerenciar outros equipamentos de redes totalmente ?pticas. Por essas raz?es, o trabalho pode ser ?til para outros grupos de pesquisa ou para empresas que necessitem avaliar novas tecnologias em redes ?pticas, como a implementa??o de algoritmos de aloca??o de comprimentos de onda ou de estrat?gias para a monitora??o da qualidade de sinais. Com o intuito de auxiliar o trabalho de outros grupos que precisem realizar a ger?ncia de equipamentos, um ap?ndice dessa disserta??o tamb?m apresenta uma descri??o detalhada dos procedimentos (nem sempre explicitamente indicados na literatura) necess?rios para atingir esse objetivo.
4

Étude des potentialités offertes par les technologies de transmission optique flexible pour les réseaux métro / coeur / Study of the potentialities offered by the flexible optical transmission technologies for metro and core networks

Blouza, Sofiene 16 May 2013 (has links)
L'évolution vers de nouveaux services, comme la TV à la demande, nécessitant de grosses bandes passantes remet en question les débits transportés par chaque canal optique d'un réseau WDM. Les débits des canaux ont atteint aujourd'hui les 100 Gbit/s. Cette montée en débit doit être accompagnée par de nouvelles fonctionnalités au sein des réseaux de transport optiques. Améliorer la flexibilité et assurer la transparence des réseaux optiques sont des défis très importants auxquels les opérateurs doivent faire face aujourd'hui. Un réseau optique est dit transparent, si les signaux optiques transportés ne subissent aucune conversion optoélectronique sauf au moment de leur insertion et de leur extraction dans le réseau optique. La flexibilité, quant à elle, concerne principalement les fonctions d'agrégation et de désagrégation optiques. Aujourd'hui ces fonctions d'agrégation et de désagrégation sont réalisées dans le domaine électronique, ce qui avec la montée du débit, va engendrer un coût important pour les opérateurs. Une manière d'y remédier serait de trouver une technologie adaptée à la montée du débit et offrant la possibilité de faire de l'agrégation et de la désagrégation optique des flux de trafics. Dans cette thèse nous proposons d'étudier une technique de commutation tout-optique offrant la possibilité de faire de la commutation optique intra-canal. Cette technique, baptisée multi-bande OFDM, consiste à diviser un canal WDM en plusieurs entités appelées sous-bandes. Le nombre de ces entités dépend des contraintes technologiques des équipements utilisés pour générer le canal multi-bande (les filtres optiques, les convertisseurs analogiques/numérique et numériques/analogiques). Nous comparons la technologie multi-bande OFDM par rapport à des technologies tendancielles mono-bande : le cas mono-bande opaque et mono-bande transparent. Nous démontrons que la technologie multi-bande OFDM peut être un compromis entre ces deux technologies pour les futurs réseaux de télécommunications optiques. Pour ce faire, nous calculons les performances en termes de blocage. Nous étudions l'impact de la conversion de longueurs d'onde sur les réseaux multi-bande OFDM ainsi que l'impact d'augmenter les nombres de sous-bandes sur les performances du réseau. Nous dégageons les limites technologiques de cette approche. Dans une autre partie de l'étude, nous montrons l'intérêt économique de la technologie multi-bande OFDM. Nous exposons le gain en coût des émetteurs/récepteurs obtenu grâce au déploiement de la technologie multi-bande OFDM sur un réseau cœur et un réseau métropolitain. / The evolution of new telecommunication services, which requires large bandwidth, challenges bit-rates transported by each optical channel of a WDM network. Bit-rates of optical channels have now reached 100 Gbit/s. This increase in bit-rate must be supported by new features in optical network. Improve flexibility and ensure transparency of optical network, are very important challenges that telecom operators face today. An optical network is called transparent, if the transported optical signals are not converted in electrical domain except at the time of their insertion and extraction in/from the optical network. Flexibility concerns mainly the aggregation / disaggregation processes. Today, the functions of aggregation/disaggregation are made on the electrical domain. This generates a significant cost for operators. One way to avoid this would be to find a technology which offers high bit-rates and enable the aggregation and disaggregation functions in the optical domain. In this thesis, we propose to study all-optical switching technology at the sub-wavelength granularity. This technique, called multi-band OFDM, consists in dividing a WDM channel into multiple entities, called sub-bands. The number of sub-bands depends on the technological constraints of optical components used to transport the optical signal (optical filters, digital analogical converters, analogical digital converters, optical transponders, optical multiplexers, etc.). We compare the multi-band OFDM technology to two legacies scenarios: mono-band opaque and mono-band transparent WDM technologies. We demonstrate that the multi-band OFDM technology can be a trade-off between these two legacies scenarios. To do that, we studied the performance in terms of blocking ratio of the multi-band OFDM technology and mono-bands WDM technologies. We study the impact of increasing the number of sub-bands on network performances. We also investigate the technical limits of this technology. Moreover, we demonstrate the economic interest of the multi-band OFDM. We expose the gain on the number of transponders when the multi-band OFDM technology is deployed on metro and core network.
5

Rozšíření optického vláknového přenosového systému / Extension of optical fiber transmission system

Horský, Tomáš January 2021 (has links)
The diploma thesis describes the elaboration of a program for the simulation of an optical transmission path. The work introduces the basic parameters of optical transmission, such as attenuation, dispersion and bandwidth. Furthermore, the techniques of line code and error detection are described in the work, especially a cyclic redundancy sum. The key parameter of this thesis is dispersion of the optical signal. The work includes the characteristics of the eye diagram and its analysis. The resulting program can also be used to measure the real transmission route and its parameters.
6

Experimentální práce s POF - polymerová optická vlákna / Experimental work with POF - Polymer optical fibers

Doležal, Ondřej January 2015 (has links)
In this diploma thesis, the reader is familiarized with polymer optical fiber (POF). Firstly is mentioned theoretical background of optical fibers and optical transmission. The following are the basic properties and significant parameters of POF, a more detailed description of each type POF and their essential advantages and disadvantages in comparison with established optical fibers based on glass. The next chapter describes the area of practical issues: working with fibers and fiber installation, as well as the available connectors and methods of measurement of POF. Closely are analyzed knowledge of the practice, including the utilize in the aerospace and automotive industries, as well as in industrial networks, access data networks and local area networks. The practical part includes the measurement of basic transmission and mechanical parameters, including analysis of the results. The conclusion summarizes all the findings and results of this work, including possible future developments.

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