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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

Proposta, simulação e testes de arquitetura para redes ópticas passivas GPON e XG-PON / Proposal, simulation and tests of architecture for passive optical networks GPON and XG-PON

Cardoso, Rodrigo Alves, 1986- 06 September 2015 (has links)
Orientador: Edson Moschim / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-27T23:28:40Z (GMT). No. of bitstreams: 1 Cardoso_RodrigoAlves_M.pdf: 10022519 bytes, checksum: 6cc7c615004e4ecdf7f5acc095cd2d2f (MD5) Previous issue date: 2015 / Resumo: O objetivo deste trabalho foi propor uma arquitetura de rede óptica passiva (PON) capaz de suportar um sistema GPON e permitir a evolução para redes PON de nova geração, ou XG-PON, de maneira que ambas as tecnologias possam coexistir na mesma infraestrutura de rede óptica. Na arquitetura foram considerados um mecanismo de proteção parcial e equipamentos que possibilitam sua efetiva construção. Foi apresentado um modelo matemático que permitiu a validação da arquitetura em função do cálculo do power budget de acordo com as premissas estabelecidas pelas normas das tecnologias PON. Um modelo de cálculo de disponibilidade de redes com proteção parcial foi apresentado. De posse destes modelos foram obtidos resultados do alcance máximo da rede, número máximo de clientes suportados, as classes requeridas de equipamentos GPON e XG-PON e a relação entre o comprimento do enlace protegido e a disponibilidade, sendo obtido um alcance máximo de 13 km e disponibilidade próxima a 5-9s para uma rede com proteção parcial. O desempenho do sistema foi validado utilizando o simulador Optisystem e testes realizados em equipamentos reais / Abstract: The aim of this work was to propose a Passive Optical Network architecture (PON) capable of supporting a GPON system and enable the evolution to next-generation PON network, or XG-PON, where both technologies can coexist in the same optical network infrastructure. In the architecture were considered a partial protection mechanism and devices that allow their deployment in real situations. It was presented a mathematical model to validation of the architecture based in the power budget calculation and in the premises established by the PON technologies recommendations. A mathematical model to calc availability in networks with partial protection was presented. Using these models were obtained the maximum reach of the network, maximum supported clients, which GPON and XG-PON equipment classes were required and the relationship between the length of the protected link and availability. It was obtained a maximum reach of 13 km and network availability next to 5-9s using partial protection. The system¿s performance was validated using the Optisystem simulator and tests performed in real equipment / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica
2

Redução do tempo de zapping em serviços IPTV sobre redes GPON utilizando vídeos escaláveis / Reducing zapping time in IPTV service over GPON networks using scalable video

Mokarzel, Marcos Perez 11 August 2010 (has links)
Com a padronização das redes óticas passivas, em particular do GPON (gigabit-capable passive optical network) adotada no Brasil, uma nova gama de serviços passou a ser viável, dentre eles a transmissão de canais de TV para assinantes usando o protocolo IP (Internet protocol), sistema conhecido como IPTV. Este processo apresenta inúmeras vantagens, dentre elas a possibilidade de um número maior de canais e com qualidade variável. O grande inconveniente neste sistema é que em qualquer sistema de transmissão de TV digital o tempo de troca de canais, conhecido como tempo de zapping, pode chegar a alguns segundos. Para reduzir este problema, este trabalho descreve um processo de codificação e transmissão de IPTV em redes GPON que reduz o tempo de zapping, podendo chegar ao tempo de recuperação de um quadro (frame). O estudo foi baseado na codificação escalável em qualidade (SNR, signal to noise ratio) proposta no padrão MPEG-2 (Moving Picture Experts Group) e pode ser facilmente portado para outros padrões de codificação como os FGSs (fine grain scalability) do MPEG-4. O transporte utiliza a característica multicast das redes GPON além do protocolo IGMP (Internet group management protocol). Uma vez que o sistema IPTV propicia ao assinante vantagens como, o aumento do número de canais e a melhoria da qualidade de cada um deles devido à flexibilização da banda, este trabalho pressupõe que o assinante aceitará uma qualidade de vídeo inferior, no momento do zapping, desde que aumente com o decorrer do tempo. O aumento da qualidade é ilustrado por curvas comparativas, que mostram os tempos entre a mudança do canal, a entrada dele em baixa resolução e a melhora progressiva até a estabilidade em qualidade máxima. / With the standardization of passive optical networks, in particular GPON (gigabit-capable passive optical networks), which is adopted in Brazil, a new range of services become feasible, among them TV channels transmission to subscribers using the IP (Internet protocol), known as IPTV system, is one of the most important. This process has many advantages, including the possibility of offering a greater number of channels with variable quality. The greater inconvenience of this solution is that in any system of digital TV transmission the time to exchange channels, known as zapping time, can reach some seconds. To reduce this problem, this M.Sc thesis proposes a coding and transmission process for IPTV in GPON networks that reduces the zapping time to values smaller than one frame time. This work is based on the scalable SNR (signal to noise ratio) proposed in MPEG-2 standard and can be easily ported to other standards like FGS (fine grain scalability) in MPEG-4. Transport uses GPON multicast characteristics beside IGMP (Internet group management protocol). Once IPTV system offers many advantages like, increasing number of channels and better image quality per channel since bandwidth can be flexible. It is assumed that the IPTV subscriber will accept low video quality, at the zapping moment, but quality will increase progressively. Comparative graphics show the quality increase in terms of time between zapping, low quality video starting and the progressive quality increase up to stability in full quality.
3

Redução do tempo de zapping em serviços IPTV sobre redes GPON utilizando vídeos escaláveis / Reducing zapping time in IPTV service over GPON networks using scalable video

Marcos Perez Mokarzel 11 August 2010 (has links)
Com a padronização das redes óticas passivas, em particular do GPON (gigabit-capable passive optical network) adotada no Brasil, uma nova gama de serviços passou a ser viável, dentre eles a transmissão de canais de TV para assinantes usando o protocolo IP (Internet protocol), sistema conhecido como IPTV. Este processo apresenta inúmeras vantagens, dentre elas a possibilidade de um número maior de canais e com qualidade variável. O grande inconveniente neste sistema é que em qualquer sistema de transmissão de TV digital o tempo de troca de canais, conhecido como tempo de zapping, pode chegar a alguns segundos. Para reduzir este problema, este trabalho descreve um processo de codificação e transmissão de IPTV em redes GPON que reduz o tempo de zapping, podendo chegar ao tempo de recuperação de um quadro (frame). O estudo foi baseado na codificação escalável em qualidade (SNR, signal to noise ratio) proposta no padrão MPEG-2 (Moving Picture Experts Group) e pode ser facilmente portado para outros padrões de codificação como os FGSs (fine grain scalability) do MPEG-4. O transporte utiliza a característica multicast das redes GPON além do protocolo IGMP (Internet group management protocol). Uma vez que o sistema IPTV propicia ao assinante vantagens como, o aumento do número de canais e a melhoria da qualidade de cada um deles devido à flexibilização da banda, este trabalho pressupõe que o assinante aceitará uma qualidade de vídeo inferior, no momento do zapping, desde que aumente com o decorrer do tempo. O aumento da qualidade é ilustrado por curvas comparativas, que mostram os tempos entre a mudança do canal, a entrada dele em baixa resolução e a melhora progressiva até a estabilidade em qualidade máxima. / With the standardization of passive optical networks, in particular GPON (gigabit-capable passive optical networks), which is adopted in Brazil, a new range of services become feasible, among them TV channels transmission to subscribers using the IP (Internet protocol), known as IPTV system, is one of the most important. This process has many advantages, including the possibility of offering a greater number of channels with variable quality. The greater inconvenience of this solution is that in any system of digital TV transmission the time to exchange channels, known as zapping time, can reach some seconds. To reduce this problem, this M.Sc thesis proposes a coding and transmission process for IPTV in GPON networks that reduces the zapping time to values smaller than one frame time. This work is based on the scalable SNR (signal to noise ratio) proposed in MPEG-2 standard and can be easily ported to other standards like FGS (fine grain scalability) in MPEG-4. Transport uses GPON multicast characteristics beside IGMP (Internet group management protocol). Once IPTV system offers many advantages like, increasing number of channels and better image quality per channel since bandwidth can be flexible. It is assumed that the IPTV subscriber will accept low video quality, at the zapping moment, but quality will increase progressively. Comparative graphics show the quality increase in terms of time between zapping, low quality video starting and the progressive quality increase up to stability in full quality.
4

光纖寬頻世代台灣網通廠商整併策略之研究 / The M&A strategy study of Taiwan telecommunication industry toward optical broadband era

婁道生, Lou, Tao Sheng Unknown Date (has links)
網路世界歷經十年的發展後,消費者對於網路交易的低成本和安全性開始廣泛認同與接受,從入口網站的架設、網路遊戲、搜尋引擎、即時通訊、網路視訊和一般電子商務等,吸引了愈來愈多的企業開發網路商機,寬頻接取也將繼水、電、瓦斯之後成為第四個公用事業,不僅僅帶來了生活的便利,更是國家競爭力的重要指標。而為因應全球數位生活之蓬勃發展,也將有各式創意應用服務激盪科技創新技術,進而活化數位生活內容。隨著大量寬頻數位設備投入,如何有效且適時導入新世代的寬頻網路接取技術更形重要。本論文透過對網通產業市場發展、技術演進、應用與商業模式開發等面向作全面性的討論,從全球市場的展望回頭檢視國內網通業者目前的策略和技術缺口,並針對未來在網通產業鏈定位與成長瓶頸提出觀察,再以模擬個案提出可能的合作方式—購併,期能對國內網通產業下一階段的發展有所貢獻。
5

10G GPON Management System Study and Implementation

Li, Jia January 2009 (has links)
<p>This thesis includes the GPON management system concept study and implementation work to translate the command line interface management mechanism to a user friendly GUI (graphic user interface). The original system was developed in C program with a client-server structure. The new system retains the same communication structure and protocol interface between the OLT PON card and user workstations. On the workstation side, a new GUI management client application is developed in Java to offer the similar functionalities as the original one, and a totally new graphic real-time system traffic statistics function is integrated to make it easier for user to monitor system traffic information in real time.</p><p> </p><p>The main object of this project is to study the GPON specifications, and understand GPON system working procedure and traffic transmission principle. On the other hand, ‘original system management application’ study is necessary including third party documentation reading and C code understanding. This study has resulted in the development of a new application in Java with third party user libraries and plug-ins. This new application has been tested using basic function tests executed in the GPON lab environment.</p>
6

10G GPON Management System Study and Implementation

Li, Jia January 2009 (has links)
This thesis includes the GPON management system concept study and implementation work to translate the command line interface management mechanism to a user friendly GUI (graphic user interface). The original system was developed in C program with a client-server structure. The new system retains the same communication structure and protocol interface between the OLT PON card and user workstations. On the workstation side, a new GUI management client application is developed in Java to offer the similar functionalities as the original one, and a totally new graphic real-time system traffic statistics function is integrated to make it easier for user to monitor system traffic information in real time.   The main object of this project is to study the GPON specifications, and understand GPON system working procedure and traffic transmission principle. On the other hand, ‘original system management application’ study is necessary including third party documentation reading and C code understanding. This study has resulted in the development of a new application in Java with third party user libraries and plug-ins. This new application has been tested using basic function tests executed in the GPON lab environment.
7

A CMOS QPSK Demodulator Frontend for GPON

Chen, Fei 30 June 2010 (has links)
This thesis examines the design of a QPSK demodulator frontend for GPON transceiver at end user's side. Since lowering the cost of the terminal transceivers in an access network like GPON is a key requirement, CMOS technology is used and several area-saving design techniques are applied. The designed frontend circuit saved more than 80% area of the key components like the mixers and the QVCO than some published designs which can also fit the application. A measurement in frequency domain and a simulation in time domain verified that this frontend is able to demodulate a QPSK signal with a data rate as high as 5 Gbit/s. Two structures of quadrature oscillators are firstly presented and compared. One is an LC QVCO centered at 5 GHz, which has a tuning range of 3 GHz, a phase noise of -100.8 dBc/Hz at 1 MHz offset, and an area of 0.15 mm2 excluding pads. The other is a ring QVCO which only takes an area of 0.019 mm2. But it has a higher phase noise of -81 dBc/Hz at 1 MHz offset. Then two broadband mixers are described separately. The first one provides a high conversion gain, but its input linearity is insufficient to meet the input power requirement. The second mixer obtains required input linearity but with a trade-off of conversion gain. Both mixers have a broadband input impedance match from 2 GHz to 8 GHz. The first mixer has a conversion gain of 8.5 dB and an input 1 dB compresion point at -17 dBm. The second mixer has a conversion gain of -7 dB with an on-chip buffer or -2.1 dB without buffer, but an input 1 dB compresion point at -5 dBm. A frontend circuit is lastly presented. It integrates the compact ring QVCO, two broadband mixers with high input linearity, and two second-order LC ladder low pass filters. A Frequency domain measurement shows the expected spectrum down conversion of a 2.5 Gsym/s QPSK signal centered at 5 GHz. The whole frontend circuit including pads takes 1 mm2 area, and consumed 157 mW power. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-06-29 10:59:45.312
8

Systém sledování změn v pasivních optických sítích / System for monitoring changes in passive optical networks

Pancák, Matej January 2021 (has links)
This diploma thesis describes a design and implementation of a system for monitoring events in passive optical networks, specifically in GPON networks. The main technologies used in the implementation of this system are Apache Kafka, Docker and the Python programming language. Within the created application, several filters are implemented. This filters obtain essential information from the captured frames in terms of traffic analysis on the given network. The result of the thesis is a functional system that from the captured GPON frames obtains information about the network traffic and stores them in the Apache Kafka, where the stored data is accessible for further processing. The work also provides examples of how to process the stored data, along with information about their meaning and structure.
9

Design of silicon-based equalization techniques for band limited giga hertz channels

Kim, Hyoung soo 08 April 2010 (has links)
The object of this research is to develop a solution for band-limited channels. Backplane channels and GPON channels are investigated to apply an equalization technique. Different lengths of backplane channels are measured with different signal speeds to investigate the channel performance. Also a GPON system with different fiber lengths is designed and set up in a lab to measure the BER performance. The GPON system utilizes a Fabry-Perot laser for the most economical solution. After the circuits are fabricated, they are inserted into the system to measure the performance of the channels with equalizers. Both the backplane and the GPON system show successful channel improvement in measured eye diagrams and BER. To expedite the procedure and eventually build an adaptive system which could be inserted and self-optimizing, we found it essential to monitor the output of the equalizer. A novel analog way to achieve this goal is suggested. All the equalizers mentioned in this dissertation have one summing node to add up all the values from VGAs. This structure is very efficient, but in the event that there are too many VGAs, it draws too much current through the one node. This issue is dealt with by the design of two nine tap equalizers, which are compared to assess the difference in performance between the unbalanced structure and the balanced structure.
10

Técnicas de testes aplicadas a software embarcado em redes ópticas / Tests techniques applied to embedded software in optical networks

Fadel, Aline Cristine, 1984- 19 August 2018 (has links)
Orientadores: Regina Lúcia de Oliveira Moraes, Eliane Martins / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-19T14:09:37Z (GMT). No. of bitstreams: 1 Fadel_AlineCristine_M.pdf: 3259764 bytes, checksum: a287ca33254d027f23e2f2f818464ee1 (MD5) Previous issue date: 2011 / Resumo: Esse trabalho apresenta os detalhes e os resultados de testes automatizados e manuais que utilizaram a técnica de injeção de falhas e que foram aplicados em redes ópticas. No primeiro experimento o teste foi automatizado e utilizou a emulação de falhas físicas baseadas na máquina de estados do software embarcado dessa rede. Para esse teste foi utilizado uma chave óptica que é controlada por um robô de testes. O segundo experimento foi um teste manual, que injetou falhas nas mensagens de comunicação do protocolo dessa rede, a fim de validar os mecanismos de tolerância a falhas do software central dessa rede. Esse experimento utilizou a metodologia Conformance and Fault injection para preparar, executar e relatar os resultados dos casos de testes. Nos dois experimentos também foi utilizado um padrão de documentação de testes que visa facilitar a reprodução dos testes, a fim de que eles possam ser aplicados em outros ambientes. Com a aplicação desses testes, a rede óptica pode alcançar uma maior confiabilidade, disponibilidade e robustez, que são características essenciais para sistemas que requerem alta dependabilidade / Abstract: This work presents the details and the results of automatic and manual tests that used the fault injection technique and were applied on GPON network. In the first experiment the test was automated, and it performed the emulation of physical faults based on the state machine of the embedded software in this network. In this test is used an optical switch that is controlled by a test robot. The second experiment was a manual test, which injected faults on protocol communication message exchanged through the optical network, in order to validate the main software fault tolerance mechanisms. This experiment used a Conformance and Fault injection methodology to prepare, execute and report the results of the test cases. In both experiments, it was used a standard test documentation to facilitate the reproduction of the tests, so that they can be applied in other environments. With applying both tests, the optical networks reach greater reliability, availability and robustness. These attributes are essential for systems that require high dependability / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia

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