Spelling suggestions: "subject:"antransmission systems"" "subject:"entransmission systems""
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Distributed asynchronous optimal routing in data networksJanuary 1984 (has links)
John N. Tsitsiklis, Dimitri P. Bertsekas. / Bibliography: leaf 5. / "August 1984." / DARPA Contract No. ONR-N00014-75-C-1183
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Failsafe distributed optimal routing in data-communication networksJanuary 1979 (has links)
by M. Sidi, A. Segall. / Bibliography: p. 146-148. / Research supported by ARPA Contract N00014-75-C-1183, ONR Contract ONR-N)))14-77-C-0532.
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Notes on optimal routing and flow control for communication networksJanuary 1981 (has links)
by Dimitri P. Bertsekas. / Bibliography: p. 55-56. / "December 1981." / Defense Advanced Research Projects Agency contract No. ONR-N00014-75-C-1183
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Loops in multicommodity flowsJanuary 1974 (has links)
Robert G. Gallager. / Caption title. / Includes bibliographical references. / Supported in part by ARPA under Grant ONR/N00014-75-C-1183 National Science Foundation Grant NSF/ENG76-24447
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A busy-tone-multiple-access-type scheme for packet-radio networksJanuary 1981 (has links)
Moshe Sidi, Adrian Segall. / Bibliography: leaf 8. / "Contract ONR/N00014-77-C-0532"
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Microwave data transmission by means of an optimal bandwidth multichannel QPSK systemMalan, Jacques de Villiers January 2004 (has links)
Thesis (MScEng)--Stellenbosch University, 2004. / Full text to be digitised and attached to bibliographic record. / ENGLISH ABSTRACT: The increase in the complexity and functionality of new satellites leads to a
growing demand for a digital communication system operating at a much higher bit
rate than before. The main purpose of this thesis is to address precisely this
problem.
The theory as well as a practical high speed system are custom-developed. The
goal of this thesis is not to reinvent the wheel, but to use off-the-shelf products as far
as possible. This system demonstrates that a very high data rate is not out of reach
for a developer with limited funds.
The secondary goal is to understand the operation of this communication system.
The emphasis is on the inaccuracies in the system. A design tool is created to act as
a vehicle for understanding the influence of a single variable on the performance of
the entire system. / AFRIKAANSE OPSOMMING: Die toename in die kompleksiteit en funksionaliteit van nuwe satelliete lei tot die
groeiende behoefte aan 'n digitale kommunikasiestelsel wat teen "n heelwat hoër bis
spoed funksioneer. Die hoofdoel van hierdie tesis is om juis hierdie probleem aan te
spreek.
Die teorie en 'n praktiese hoëspoed stelsel is ontwikkel. Die doel van die tesis is
nie om die wiel te herontdek nie maar om sover moontlik bestaande produkte in die
ontwerp van die stelsel te gebruik. Die stelsel demonstreer dat 'n hoëspoed
datatempo nie buite die bereik van 'n ontwikkelaar met beperkte fondse is nie.
'n Verdere doelwit is om die funksionering van die kommunikasie stelsel te begryp.
Klem is gelê op die onakkuraathede in die kommunikasiestelsel. Ontwikkeling
sagteware is geskep as "n metode om die invloed van "n enkele veranderlike op die
werkverrigting van die stelsel as geheel te begryp.
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Models and applications of wireless networks in rural environmentsLi, Yang January 2005 (has links)
Magister Scientiae - MSc / With the unprecedented growth of the communication industry that the world is experiencing, the demand from rural inhabitants for high quality communications at an economically affordable cost is growing. However, rural areas are rather restricted from deploying communication services due to the rough natural environment, and the shortage of rudimentary communication facilities and technical personnel. Appropriate models for building rural wireless networks and a concomitant simulation environment are, therefore, expected to enable the construction of technologically-optimal and economically-efficient networks in specified rural areas.The research has set up two independent models, one for the economic need and the other for the technical need of building networks in rural areas. One model was the Impact of Telecommunications Model, which disclosed the importance of building a wireless network in specified rural areas by choosing an economic parameter to forecast the profitability of the network. The other was the Service Model, which collected primitive data from given rural areas and abstracted these data by flowing them through four technical layers to form the predicted technical wireless network. Both of the models had been applied to real-world cases to demonstrate how to use them.A simulation environment was finally designed and implemented to realize the above two models for the sake of instantiation. This environment could simulate the specified rural network by constructing a wireless network on the invented areas and evaluating its quality and economic efficiency. It was written in Scilab simulation language, which was an open source. / South Africa
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Sistema de comunicação de dados pela rede elétrica, de baixo custo, aplicado a uma rede de medidores individuais de energia elétrica residencial = concepção do circuito, protótipo e testes / Communication system to the AC power, low cost, applied to a network of individual meters for residential electricity, circuit design, prototyping and testingAiroldi, Douglas 19 August 2018 (has links)
Orientador: José Antonio Siqueira Dias / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-19T07:47:20Z (GMT). No. of bitstreams: 1
Airoldi_Douglas_M.pdf: 6691455 bytes, checksum: c3353281e717bd0415dc9ce4a5762ba6 (MD5)
Previous issue date: 2011 / Resumo: Este trabalho é parte de um projeto de pesquisa e desenvolvimento de uma rede de mini-medidores de energia, de baixíssimo custo, que se comunica com uma central, que armazena todas as informações relativas ao consumo de energia elétrica, de cada um dos pontos de consumo de uma residência. Ao fim de um período, fornece ao consumidor condições de analisar a distribuição do seu gasto com energia elétrica por ponto medido. Neste trabalho foi desenvolvido um sistema de comunicação de dados pela rede elétrica, também conhecida como Power Line Communication (PLC)). O hardware, de baixo custo, é composto por microcontrolador e um modem integrado que utiliza o processo Amplitude Shift Keying (ASK), com taxas de comunicação entre 600 e 1200 bps (bits por segundo). O firmware criado é composto de um protocolo que realiza a comunicação half-duplex entre duas estações de medição, permitindo ao transmissor da informação, saber se a mesma foi recebida com integridade / Abstract: This work is part of a research project and develops a network of mini-power meters, very low cost, which communicate with a central, which stores all information relating to the consumption of electricity, each of the points consumption of a residence. At one time, it gives the consumer the ability to analyze the distribution of its spending power by the measured point. We have developed a communication system for data grid, also known as Power Line Communication (PLC). The hardware, low cost, consists of microcontroller and an integrated modem that uses the process Amplitude Shift Keying (ASK), with communication rates between 600 and 1200 bps (bits per second). The firmware is created consisting of a protocol that performs half-duplex communication between two measuring stations, allowing the transmitter of information, whether it was received with integrity / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica
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[en] IMPLEMENTATION OF ALL OPTICAL CLOCK VECOVERY CIRCUITS / [pt] ESTUDO E IMPLEMENTAÇÃO DE RECUPERAÇÃO DE RELÓGIO POR PROCESSO ÓPTICOVALTER SILVA BARBIO 22 August 2006 (has links)
[pt] A tendência de um rápido aumento nas taxas de transmissão
utilizadas em sistemas de comunicações ópticas, impõe que
sejam repensadas as tecnologias e princípios de fabricação
dos diversos elementos de um sistema de transmissão ou de
recepção. Em breve, sistemas operando em taxas superiores
a 100Gbits/s serão uma realidade. Este trabalho propõe-se
a analisar o problema da extração de relógio em receptores
ópticos de alta capacidade. O processo, atualmente
empregado, é completamente elétrico sendo dificultado
devido a sensibilidade dos componentes eletrônicos à
freqüência de operação. Apresenta-se neste trabalho um
método de recuperação de relógio por processo óptico,
utilizando-se como elemento fundamental um laser DFB multi-
seção. Inicialmente será realizado um estudo teórico do
fenômeno de auto-pulsação, pré-requisito para a extração
de relógio por processo óptico. Em seguida serão
apresentados e discutidos uma série de experimentos que
demonstram a recuperação de relógio por processo óptico. A
partir destas informações e das condições adequadas para a
obtenção do fenômeno, implementa-se um set-up experimental
utilizando-se um laser InGaAsP/InP DFB dupla-seção, a
partir do qual obtém-se recuperação de relógio por
processo óptico em 1,24Gbits/s e 2,48Gbits/s nos formatos
RZ e NRZ. / [en] Today bit-rates increase quickly in optical communications
sustems. New technologies and fabrication process
discovers are fundamental to the development of several
devices in the transmission and reception systems. Soon,
optical communication systems working in 100Gbits/s will
be a reality. This work intends to solve the problem of
clock recovery in high capacitu optical receivers. The
process employed nawadays is completely electrical. As it
is known, electronics devices are limited in frequency,
and won´t operate propely in such high bit-rates. In this
work a optical clock recovery method is shown, using a
multi-section laser, as main element. The first step will
be the description of a theoretical study of the self-
pulsation phenomenon, allowing the understanding of the
mechanism of optical clock recovery. Afterwards a series
of experiments that show optical clock recovery are
preented and discussed. A experimental set-up is
implemented, utilizing a InGsAsP/InP doublesection DFB
laser, and optical clock recovery is obtained from
1,24Gbits/s and 2,48Gbits/s bit streams, in RZ and NRZ
formats.
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Synchronization with permutation codes and Reed-Solomon codesShongwe, Thokozani Calvin 23 September 2014 (has links)
D.Ing. (Electrical And Electronic Engineering) / We address the issue of synchronization, using sync-words (or markers), for encoded data. We focus on data that is encoded using permutation codes or Reed-Solomon codes. For each type of code (permutation code and Reed-Solomon code) we give a synchronization procedure or algorithm such that synchronization is improved compared to when the procedure is not employed. The gure of merit for judging the performance is probability of synchronization (acquisition). The word acquisition is used to indicate that a sync-word is acquired or found in the right place in a frame. A new synchronization procedure for permutation codes is presented. This procedure is about nding sync-words that can be used speci cally with permutation codes, such that acceptable synchronization performance is possible even under channels with frequency selective fading/jamming, such as the power line communication channel. Our new procedure is tested with permutation codes known as distance-preserving mappings (DPMs). DPMs were chosen because they have de ned encoding and decoding procedures. Another new procedure for avoiding symbols in Reed-Solomon codes is presented. We call the procedure symbol avoidance. The symbol avoidance procedure is then used to improve the synchronization performance of Reed-Solomon codes, where known binary sync-words are used for synchronization. We give performance comparison results, in terms of probability of synchronization, where we compare Reed-Solomon with and without symbol avoidance applied.
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