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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.
51

Úzkopásmová PLC komunikace se standardy G3-PLC, PRIME a IEEE-1901.2 / Narrowband PLC communication based on G3-PLC, PRIME and IEEE-1901.2 standards

Skrášek, Tomáš January 2015 (has links)
Diploma thesis is about narrowband PLC communication standards. The theoretical part describes details of all available OFDM standards including G3-PLC, PRIME, IEEE-1901.2 and G.hnem. The practical part deals with PRIME and G3-PLC standards. In this part is also compared OFDM technology with system of single carrier frequency in environment with real interferences. The last part describes developement of two firmwares for PLC modems Texas Instruments TMDSPLCKIT-V3, which allow UART communication and remote data collection. The thesis also includes Windows application developed to display and save collected data.
52

Komunikace po silových rozvodech pro účely domácí automatizace / Power Line Communication for Home Automation Applications

Hromádka, Michal January 2014 (has links)
This thesis describes the design of a modem for a communication over residential power lines. First part is focused on the history, suitable frequency bands, modulation techniques and mainly on the selection of the optimal modem device. Second section contains the description of the hardware design of the modem itself and clarifies the implementation of the PLC module to be used as a communication interface for a full residential automation solution. Last chapters of this thesis introduce the communication protocol, design of the software for the ATmega32 MCU and present of the final field testing under real conditions.
53

Úzkopásmový PLC modem / Narrowband PLC modem

Novák, Pavel January 2016 (has links)
The theses is focused on the use of PLC technology. The aim of the thesis is creating device which communicates in a narrowband transmission frequency band. Transmission of communication between plc elements runs through the low voltage distribution network. The frequency and phase modulations are used in order to change the character of data signal. Transmitter and receiver parameters are subjects to the CENELEC standard. The theses gives more attention to the area of hardware build communication element rather than the area of programming.
54

Úzkopásmový PLC modem / Narrowband PLC modem

Novák, Pavel January 2016 (has links)
The theses is focused on the use of PLC technology. The aim of the thesis is creating device which communicates in a narrowband transmission frequency band. Transmission of communication between plc elements runs through the low voltage distribution network. The frequency and phase modulations are used in order to change the character of data signal. Transmitter and receiver parameters are subjects to the CENELEC standard. The theses gives more attention to the area of hardware build communication element rather than the area of programming.
55

Μετάδοση δεδομένων υψηλών ταχυτήτων σε γραμμές χαμηλής τάσης εντός κτιρίων : χαρακτηρισμός επικοινωνιακού μέσου και αξιοποίηση διαθέσιμου ευρους ζώνης / High speed data transission using indoor power distribution circuits : communications media characterization and available bandwidth utilization

Αναστασιάδου, Δέσποινα 25 June 2007 (has links)
Αντικείµενο της παρούσας διατριβής είναι η αξιοποίηση των γραµµών χαµηλής τάσης εντός κτιρίων για τη δηµιουργία ενός τοπικού δικτύου επικοινωνιών για µετάδοση δεδοµένων σε υψηλές ταχύτητες µε σκοπό την παροχή υπηρεσιών ευρείας ζώνης στον τελικό χρήστη. Η χρήση του δικτύου παροχής ηλεκτρικής ενέργειας ως επικοινωνιακό µέσο σε υψηλές συχνότητες εξαρτάται από την αντιµετώπιση των ιδιαίτερων χαρακτηριστικών της συµπεριφοράς του, που περιλαµβάνουν επιλεκτική εξασθένηση πλάτους συναρτήσει της συχνότητας, παραµόρφωση φάσης που εξαρτάται από τα µήκη των γραµµών, ισχυρό κρουστικό θόρυβο και παρεµβολές στενής ζώνης. Οι συνθήκες µετάδοσης επηρεάζονται επίσης δυσµενώς από την εξάρτηση των παραπάνω χαρακτηριστικών από το χρόνο, η οποία οφείλεται στη µεταβολή της φόρτισης του δικτύου. Η σύγχρονη αντιµετώπιση του επικοινωνιακού µέσου στηρίζεται σε εµπειρικά µοντέλα συµπεριφοράς, που πηγάζουν από µετρητικά δεδοµένα σε πειραµατικά δίκτυα και επιχειρεί να καλύψει αξιόπιστα µε κατάλληλες τεχνικές µετάδοσης τη ‘χειρότερη’ περίπτωση σε ότι αφορά τις συνθήκες του καναλιού, χωρίς να βοηθά στην κατανόηση των παραγόντων που επηρεάζουν τη συµπεριφορά του µέσου, ώστε να είναι εφικτή και η ουσιαστική αντιµετώπισή τους. Η παρούσα εργασία ακολουθεί µια διαφορετική προσέγγιση για την αξιοποίηση του µέσου, που στοχεύει στην ουσιαστική αντιµετώπιση της χρονικά µεταβαλλόµενης συµπεριφοράς του µέσου, προτείνοντας διαδικασίες και τεχνικές που προσαρµόζουν τη µετάδοση στο υφιστάµενο επικοινωνιακό περιβάλλον. Η ανάπτυξη των διαδικασιών αυτών στηρίχθηκε σε ένα πρότυπο περιβάλλον επικοινωνιών που καλείται pDSL (powerline Digital Subscriber Lines) και προτάθηκε για να αποτελέσει το πλαίσιο, σύµφωνα µε το οποίο αναπτύχθηκαν διαδικασίες ανίχνευσης και προσαρµογής της µετάδοσης στις συνθήκες του καναλιού. Στο pDSL περιβάλλον ορίζονται επικοινωνιακά κανάλια που ισοδυναµούν µε ‘σηµείο-προς-σηµείο’ ζεύξεις µεταξύ της pDSL πύλης (κεντρική µονάδα του δικτύου και µονάδα διασύνδεσης του τοπικού δικτύου µε άλλα δίκτυα) και των pDSL επικοινωνιακών συσκευών, όπως ονοµάζονται οι ηλεκτρονικές συσκευές που απαιτούν υπηρεσίες µετάδοσης δεδοµένων υψηλών ταχυτήτων. Η ανάπτυξη των τεχνικών µετάδοσης που αντιµετωπίζουν τις συνθήκες που επικρατούν στο επικοινωνιακό µέσο στηρίζεται στο χαρακτηρισµό της συµπεριφοράς του. Πρώτο βήµα της διαδικασίας αυτής αποτελεί η σύνδεση της απόκρισης του καναλιού µετάδοσης µε τα χαρακτηριστικά του δικτύου γραµµών. Για το σκοπό αυτό, αναπτύχθηκε και παρουσιάζεται ένας αλγόριθµος ανάλυσης της πολυοδικής µετάδοσης του σήµατος στο δίκτυο των γραµµών χαµηλής τάσης, ο οποίος προσδιορίζει µε αναλυτικό τρόπο τα προϊόντα της µετάδοσης που πραγµατοποιείται µέσω πολλαπλών διαδροµών στο δίκτυοκαι συνθέτει την κρουστική και φασµατική απόκρισή του. Ο αλγόριθµος βασίζεται στην περιγραφή της τοπολογίας, των χαρακτηριστικών µετάδοσης των καλωδίων και των εµπεδήσεων των φορτίων τερµατισµού της. Η εργασία περιλαµβάνει επίσης την ανάπτυξη δύο πειραµατικών µεθοδολογιών µε τις οποίες πραγµατοποιείται η εκτίµηση των χαρακτηριστικών µετάδοσης των καλωδίων χαµηλής τάσης στις υψηλές συχνότητες και της εµπέδησης των ηλεκτρικών φορτίων που συνδέονται στα δίκτυα αυτά. Τα µεγέθη αυτά προκαλούν την εξάρτηση της συµπεριφοράς του µέσου µετάδοσης από τη συχνότητα και το χρόνο και ο προσδιορισµός τους είναι αναγκαίος για την εφαρµογή της ανάλυσης και της πρόβλεψης της συµπεριφοράς του καναλιού µε τη βοήθεια του αλγορίθµου ανάλυσης. Η αξιοπιστία των µεθόδων πιστοποιήθηκε µε τη σύγκριση της πειραµατικής και της θεωρητικής συνάρτησης µεταφοράς των καναλιών που σχηµατίζονται σε πειραµατικές τοπολογίες γραµµών χαµηλής τάσης, οι οποίες κατασκευάστηκαν για το σκοπό αυτό. Στην παρούσα εργασία, η ανάλυση της συµπεριφοράς του µέσου πλαισιώνεται µε τη σχεδίαση και την υλοποίηση ενός εξοµοιωτή πραγµατικού χρόνου του επικοινωνιακού καναλιού, ο οποίος εξοµοιώνει τη χρονικά µεταβαλλόµενη συµπεριφορά του µέσου µε βάση την τοπολογία και τη φόρτιση του. Ο εξοµοιωτής αυτός µπορεί να αποτελέσει πολύτιµο εργαλείο ελέγχου νέων τεχνικών µετάδοσης, κάτω από διαφορετικές συνθήκες επικοινωνίες. Τέλος, µε βάση το χαρακτηρισµό της συµπεριφοράς του επικοινωνιακού µέσου που προηγήθηκε επιχειρείται η ανάπτυξη διαδικασιών που αποσκοπούν στην ανίχνευση των συνθηκών που επικρατούν στο επικοινωνιακό κανάλι και στην προσαρµογή της τεχνικής µετάδοσης σε αυτές, στα πλαίσια της pDSL αρχιτεκτονικής επικοινωνιών. Για την ανίχνευση των συνθηκών µετάδοσης στις επικοινωνιακές ζεύξεις αναπτύχθηκαν δύο επιµέρους διαδικασίες: η ‘αρχική συνθηκοθέτηση’ του καναλιού, που πραγµατοποιείται κατά την αρχικοποίηση των επικοινωνιακών ζεύξεων και η ‘ενδιάµεση συνθηκοθέτηση’ που εκτελείται περιοδικά και επανεκτιµά τις συνθήκες του καναλιού κατά τη διάρκεια της µετάδοσης. Η δεύτερη διαδικασία, η οποία υπόκειται σε εξαιρετικά αυστηρούς χρονικούς περιορισµούς, πλαισιώθηκε από µια µέθοδο πρόβλεψης της συµπεριφοράς του µέσου που επιταχύνει και συµπληρώνει τη διαδικασία ‘ενδιάµεσης συνθηκοθέτησης’ και βασίζεται στη διαθέσιµη πληροφορία εκτίµησης του καναλιού και στον αλγόριθµο ανάλυσης της µετάδοσης στο κανάλι. Η προτεινόµενη διαδικασία προσαρµογής της µετάδοσης στις τρέχουσες συνθήκες που επικρατούν στο κανάλι στοχεύει στην κατάλληλη ανακατανοµή του διαθέσιµου εύρους ζώνης στις επικοινωνιακές ζεύξεις, Η διαδικασία αξιοποιεί την πληροφορία της εκτίµησης των συνθηκών στο µέσο και επιχειρεί να χαρακτηρίσει τα διαθέσιµα υπο-κανάλια ως προς την καταλληλότητα τους για µετάδοση δεδοµένων, ώστε να τα κατανείµει µε βέλτιστο τρόπο στις ζεύξεις, ανάλογα µε τις απαιτήσεις τους σε ρυθµό µετάδοσης.
56

COMUNICAÇÃO EM LINHA E RUÍDOS SEMÂNTICOS NA RECUPERAÇÃO DE INFORMAÇÕES EM PESQUISAS CIENTÍFICAS

Lorusso, Marise Miglioli 14 August 2007 (has links)
Made available in DSpace on 2016-08-03T12:30:36Z (GMT). No. of bitstreams: 1 CAPA.pdf: 6587 bytes, checksum: 2b1e4893b77f4a03ffa888fb1f5d6d23 (MD5) Previous issue date: 2007-08-14 / The scientific researcher needs necessary information, in skillful time for conclusion of its works. With the advent of the INTERNET, the process of on-line communication, man x machine, mediated for the search mechanisms, became, simultaneously, an aid and a difficulty in the process of recovery of information. The researcher had that to adapt it the way to operate of the INTERNET and included knowledge of idiomatic differences, of terminology, beyond using instruments that supply parameters to it to get greater relevancy and relevance in the data. The use of intelligent agents for improvement of results and the reduction of semantic noises have been pointed as solutions with respect to increase of the precision in the result of the searches. The exploratory study of cases carried through it analyzes on-line research from the theory of the information and considers two forms to optimize the comunicacional process with sights to the relevancy and relevance of the gotten data: the first one suggests the application of algorithms that use mediating the controlled vocabulary as of the communication process using itself of the describers for on-line recovery. , and second the importance of the intelligent agents in the process of man-machine communication stands out.(AU) / O pesquisador científico necessita de informações precisas, em tempo hábil para conclusão de seus trabalhos. Com o advento da INTERNET, o processo de comunicação em linha, homem x máquina, mediado pelos mecanismos de busca, tornou-se, simultaneamente, um auxílio e uma dificuldade no processo de recuperação de informações. O pesquisador teve que adaptar-se ao modo de operar da INTERNET e incluiu conhecimentos de diferenças idiomáticas, de terminologia, além de utilizar instrumentos que lhe forneçam parâmetros para obter maior pertinência e relevância nos dados. O uso de agentes inteligentes para melhoria de resultados e a diminuição de ruídos semânticos têm sido apontados como soluções para aumento da precisão no resultado das buscas. O estudo de casos exploratório realizado analisa a pesquisa em linha a partir da teoria da informação e propõe duas formas de otimizar o processo comunicacional com vistas à pertinência e relevância dos dados obtidos: a primeira sugere a aplicação de algoritmos que utilizem o vocabulário controlado como mediador do processo de comunicação utilizando-se dos descritores para recuperação em linha. , e a segunda ressalta a importância dos agentes inteligentes no processo de comunicação homem-máquina.(AU)
57

Uma contribuição à análise espectral de sinais estacionários e não estacionários

Menezes, Alam Silva 01 September 2014 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-16T09:52:46Z No. of bitstreams: 1 alamsilvamenezes.pdf: 8301590 bytes, checksum: aed618e30f38206da4bf4f329924f87e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T12:30:53Z (GMT) No. of bitstreams: 1 alamsilvamenezes.pdf: 8301590 bytes, checksum: aed618e30f38206da4bf4f329924f87e (MD5) / Made available in DSpace on 2016-02-26T12:30:53Z (GMT). No. of bitstreams: 1 alamsilvamenezes.pdf: 8301590 bytes, checksum: aed618e30f38206da4bf4f329924f87e (MD5) Previous issue date: 2014-09-01 / A presente tese propõe soluções ao problema da explicitação do conteúdo espectral de processos estacionários e não estacionários, com aplicações na estimação de frequência, estimação da densidade espectral de potência e no monitoramento do espectro. A técnica de estimação de frequência proposta nesta tese, baseada na warped discrete Fourier transform, apresenta, de acordo com as simulações computacionais, o melhor desempenho frente às demais técnicas comparadas, atingindo o Cramer-Rao bound para uma ampla faixa de relação sinal ruído. Em relação a estimação da densidade espectral de potência, a Hartley Multitaper method, proposta nesta tese, apresenta desempenho similar à multitaper method, em termos da variância de estimação e da polarização do espectro, mas simpli cação de implementação. Uma técnica para monitoramento do espectro para sistemas power line communication é proposta, levando em consideração o conceito de quanta e a diversidade observada quando os sinais são aquisitados a partir da rede de energia elétrica e do ar. Baseando-se em sinais sintéticos, gerados em computador, assim como dados de medição do espectro, obtidos utilizando uma antena e o cabo de energia elétrica como elementos sensores, veri fica-se que o desempenho da técnica proposta supera a monitoração padrão, sobretudo quando a diversidade gerada pelo cabo e pela antena sobre o sinal monitorado é explorada na detecção. / This dissertation aims at discussing solutions to deal with spectral analysis of stationary and non-stationary processes for frequency estimation, power spectral density estimation and spectral monitoring applications. The frequency estimation techniques are assessed through computer simulations. The proposed technique for frequency estimation is based on warped discrete Fourier transform outperforms other techniques, achieving the Cramer-Rao Bound for a wide range of signal to noise ratio. Regarding the power spectral density estimation, the proposed Hartley Multitaper Method shows similar performance, in terms of variance of estimates and polarization spectrum; however, it can simplify the implementation complexity. The introduced spectrum sensing technique is based on quanta de nition and the diversity o ered by the signals acquired from the electric power grids and the air. Based on computer-generation data and those one obtained during a measurement campaign, which one in this thesis is evaluated using synthetic signals, generated by computer, as well as measurement data of the spectrum. The numerical results show that the proposed technique outperforms a previous technique and can attain the very detection ratio and the very low false alarm when the diversity yielded by electric power grid and air is exploited.
58

Estudo da técnica FBMC aplicada em Power line communication

Franzin, Renato Pivesso 27 October 2017 (has links)
Submitted by Marta Toyoda (1144061@mackenzie.br) on 2018-02-08T19:53:42Z No. of bitstreams: 2 RENATO PIVESSO FRANZIN.pdf: 4022365 bytes, checksum: 9a9f1f649dcaff054b2cc033a7c69dba (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Paola Damato (repositorio@mackenzie.br) on 2018-02-22T13:30:38Z (GMT) No. of bitstreams: 2 RENATO PIVESSO FRANZIN.pdf: 4022365 bytes, checksum: 9a9f1f649dcaff054b2cc033a7c69dba (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-22T13:30:38Z (GMT). No. of bitstreams: 2 RENATO PIVESSO FRANZIN.pdf: 4022365 bytes, checksum: 9a9f1f649dcaff054b2cc033a7c69dba (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-10-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present dissertation presented a comparative analysis between OFDM and FBMC modulation techniques, applied in Power Line Communication (PLC) technology, considering realistic channel models. With the growing demand for access to broadband data networks, there is a need to integrate the various data communication technologies. In this scenario, PLC networks can o er a viable alternative as a provider of network access, since they use the infrastructure of the transmission lines. However, the electrical network is a hostile medium for data transmission, presenting impedance mismatches, noise interference and signal propagation in multipath, characterizing the PLC channel model. With the objective of increasing the data transmission rate, as well as to obtain a better utilization of available bandwidth, the present work proposed to replace the OFDM technique by FBMC in PLC networks. For this, a study of the channel model was carried out to obtain the necessary parameters for the computational simulations through Matlab software. The OFDM and FBMC techniques were implemented according to IEEE 1901 standard technical speci cations. With the results obtained in the simulations, it was veri ed that the FBMC is more robust the channel interferences, presenting gains of up to 8 dB in the bit error rate, and an increase in the data transmission rate and spectral e ciency of up to 25% in relation to OFDM. Therefore, the FBMC technique can be implemented at the physical layer of the IEEE 1901 standard, replacing OFDM. / A presente dissertação apresentou uma análise comparativa entre as t_ecnicas de modulação OFDM e FBMC, aplicadas na tecnologia Power Line Communication (PLC), considerando modelos realísticos de canais. Com a crescente demanda ao acesso das redes de dados em banda larga, há uma necessidade de integração das diversas tecnologias de comunicação de dados. Nesse cenário, as redes PLC podem oferecer uma alternativa viável como provedora de acesso à rede, pois utilizam a infraestrutura das linhas de transmissão de energia elétrica. Entretanto, a rede elétrica é um meio hostil para transmissão de dados, apresentando desajustes de impedância, interferência de ruído e propagação do sinal em multipercursos, caracterizando o modelo do canal PLC. Com o objetivo de aumentar a taxa de transmissão de dados, como também obter um melhor aproveitamento da largura de banda disponível, o presente trabalho propôs substituir a técnica OFDM pela FBMC em redes PLC. Para isso, foi realizado um estudo do modelo do canal, para obter os parâmetros necessários para as simulações computacionais por meio do software Matlab. As técnicas OFDM e FBMC foram implementadas de acordo com especificações técnicas do padrão IEEE 1901. Com os resultados obtidos nas simulações, constatou que o FBMC é mais robusto as interferências do canal, apresentando ganhos de até 8 dB na taxa de erro de bit, e um incremento na taxa de transmissão de dados e eficiência espectral de até 25% em relação ao OFDM. Portanto, a técnica FBMC pode ser implementada na camada física do padrão IEEE 1901, substituindo o OFDM.
59

Comunicação digital em canais PLC: técnicas de transmissão, detecção e caracterização de canais PLC outdoor brasileiros

Picorone, Antonio Angelo Missiaggia 22 August 2014 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-04-25T12:36:15Z No. of bitstreams: 1 antonioangelomissiaggiapicorone.pdf: 6590019 bytes, checksum: 115ef6e90742599945ac5e9c8c44cb2c (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-04-25T15:26:22Z (GMT) No. of bitstreams: 1 antonioangelomissiaggiapicorone.pdf: 6590019 bytes, checksum: 115ef6e90742599945ac5e9c8c44cb2c (MD5) / Made available in DSpace on 2017-04-25T15:26:22Z (GMT). No. of bitstreams: 1 antonioangelomissiaggiapicorone.pdf: 6590019 bytes, checksum: 115ef6e90742599945ac5e9c8c44cb2c (MD5) Previous issue date: 2014-08-22 / Esta tese discute a medição e a caracterização das redes de distribuição de energia elétrica de baixa tensão (RDE-BT) e externa (outdoor) como meio de comunicação de dados para sistemas power line communication (PLC). São apresentados e discutidos diversos parâmetros obtidos a partir de uma campanha de medição realizada na RDE-BT de uma concessionária brasileira. Dentre os parâmetros analisados destacam-se o tempo de coerência, banda de coerência, espalhamento do atraso, comprimento da resposta ao impulso do canal e capacidade do canal, quando se considera as bandas de frequências de 1,7 a 30 MHz, 1,7 a 50 MHz e 1,7 a 100 MHz. As análises estatísticas evidenciam o potencial da rede de energia elétrica como meio de comunicação e discute os limites dessa potencialidade. Além disso, são propostos modelos de densidade espectral de potência dos ruídos, caracterização esparsa de canais PLC e proposto um modelo para geração de canais PLC variantes no tempo, cujo tempo de coerência entre as realizações dos canais é controlado. A estimação de canais PLC é apresentada como uma oportunidade de aplicação das técnicas de amostragem compressiva. Os resultados relacionados com as modelagens propostas constituem um ferramental de grande utilidade para projetar e analisar o desempenho de sistemas PLC. / This dissertation aims at discussing the measurement and characterization of outdoor electric power grid of low voltage as communication medium (power line communication - PLC). Statistical analyses carried out on several parameters such as average channel gain, coherence time, coherence bandwidth, delay spread, length of the channel impulse response, and channel capacity, when it is considered the frequency bands from 1.7 to 30 MHz, from 1.7 up to 50 MHz, and from 1.7 up to 100 MHz, are presented. These analyses reveal the circumstances in which outdoor and low-voltage electric power grids can be advantageous to support a reliable and efficient PLC system operation. Moreover, power spectral density models of additive noise and sparse representation of PLC channels are proposed. Also, a PLC time-varying channels model generator that makes use of coherence time is introduced. The proposed model generator, which is validated with measured PLC channels, is an effective tool to carry out performance analysis of PLC systems. Finally, PLC channel estimation is highlighted as an opportunity for the application of compressive sampling-based techniques. The use of traditional OFDM - based channel estimation techniques and the ones based on compressive sensing gives some directions for advancing channel estimation techniques for PLC channels.
60

Analyses of a low-bit rate hybrid PLC-wireless single-relay channel

Fernandes, Victor 23 February 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-07-19T18:40:00Z No. of bitstreams: 1 victorfernandes.pdf: 1092306 bytes, checksum: 4a32aa04ed1256ce18768180de089629 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-09T12:20:45Z (GMT) No. of bitstreams: 1 victorfernandes.pdf: 1092306 bytes, checksum: 4a32aa04ed1256ce18768180de089629 (MD5) / Made available in DSpace on 2017-08-09T12:20:45Z (GMT). No. of bitstreams: 1 victorfernandes.pdf: 1092306 bytes, checksum: 4a32aa04ed1256ce18768180de089629 (MD5) Previous issue date: 2017-02-23 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Essa dissertação tem por objetivo mostrar os benefícios em termos de desempenho e confiabilidade de um modelo de canal híbrido de baixa taxa de dados que pode ser aplicado a smart grids e internet das coisas. Esse modelo é chamado de hybrid power line communication-wireless single-relay channel (HSRC), que consiste do uso paralelo e mútuo dos modelos single-relay channel baseado em transmissão de dados via rede elétrica e sem fio. Para mostrar os benefícios do mesmo, foi considerado que a posição do nó de retransmissão é variável, também foi assumida alocação de potência uniforme e ótima sob restrição de potência, bem como o uso de dois protocolos de cooperação: amplify-andforward (AF) e decode-and-forward (DF). Além disso, essa dissertação discute o modelo HSRC incompleto, que é caracterizado pela perda de um enlace de comunicação de dados ou uma interface de comunicação de um nó no modelo HSRC. Primeiramente, foi apresentada a formulação matemática no que tange a taxa de dados ergódica e probabilidade de outage dos dois modelos mencionados. Em seguida, foi realizada a análise numérica dos mesmos. Por fim, os resultados numéricos foram analisados e mostraram que tanto o HSRC quanto o HSRC incompleto têm performance melhores do que o single-relay channel baseado em transmissão de dados via rede elétrica ou sem fio para todas as posições do nó de retransmissão e protocolos de cooperação considerados. Também, os resultados mostraram que a posição relativa entre os nós de fonte, destino e de retransmissão impactam significativamente na taxa de dados ergódica bem como na probabilidade de outage. Ainda, foi mostrado o impacto da perda de cada enlace de comunicação de dados ou interface de comunicação de um nó (HSRC incompleto) quando a posição relativa do nó de retransmissão muda. Por último, é mostrado que a diferença de desempenho entre os protocolos de cooperação AF e DF reduz quando o modelo HSRC é utilizado e que a melhor posição para o nó de retransmissão é entre os nós fonte e destino em termos de taxa de dados ergódica. / This dissertation aims at discussing improvements of performance and reliability of lowbit rate data communication technologies applied to smart grids and internet of things. In this regard, a comprehensive analysis of the ergodic achievable data rate and the outage probability of the so-called low-bit rate hybrid power line communication-wireless singlerelay channel (HSRC) model, which jointly and in parallel uses power line and wireless channels for data transmission, is presented. In order to highlight the benefits of such hybrid channel model for the target applications when the relative position of relay node changes, optimal and uniform power allocations under sum power constraint, amplifyand-forward (AF) and decode-and-forward (DF) cooperative protocols are taken into account. Moreover, this dissertation discusses the so-called incomplete HSRC which is characterized by the loss of one data communication link or node communication interface in a HSRC. Numerical results show that the HSRC and incomplete HSRC remarkably outperform power line or wireless single-relay channels for all considered positions of the relay node and the chosen cooperative protocols. Furthermore, these results show that the relative distances among source, relay and destination nodes significantly impact the achievable data rate and outage probabilities. In addition, the impact of each missing data communication link or node communication interface (incomplete HSRC) when the relay position, relative to source and destination nodes, changes is quantified. Finally, but not the least, it is shown that the performance difference between AF and DF protocols reduces when the HSRC model is taken into account and that the best relay position is in the middle between source and destination nodes.

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