Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital
Autor(a) principal: | |
---|---|
Data de Publicação: | 2002 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10451/14001 |
Resumo: | This work applies a pattern recognition system based on artificial neural networks to the demodulation of digitally modulated signals. It is intended to explore the ability that may be displayed by neural networks to reconstruct patterns corrupted by noise. A competition neural network is presented that is able to perform digital modulation reception tasks: frequency and phase carrier synchronization; symbol synchronization; systematic compensation of symbol rotation. Some tasks imply post-processing of neural network output. The presented system does not require carrier synchronization with a local oscillator. Same details of the proposed methods are new contributions, which are stressed upon discussion. It was indented to guarantee future implementation of the neural network using programmable logic arrays. It is necessary to limit the proposed architecture size to an acceptable number of logical gates. On the other hand it is necessary to guarantee that each given stimulus vector is fully processed before the next one arrives (assuring real time operation). This work is mainly focused on 4-PSK (or QPSK) modulation, since this kind of modulation is used in a wide range of digital modulation applications (including third generation mobile phones). Generalization possibilities to M-PSK and M-QAM are discussed. Simulation methods were applied to evaluate system performance. Results indicate that the system is able to perform accordingly to objectives |
id |
RCAP_1afc40412fa9605fd9160257c2ad8f0c |
---|---|
oai_identifier_str |
oai:repositorio.ul.pt:10451/14001 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação DigitalArtificial neural networkscompetition networkspattern recognitiontelecommunicationsdigital modulationdemodulatorThis work applies a pattern recognition system based on artificial neural networks to the demodulation of digitally modulated signals. It is intended to explore the ability that may be displayed by neural networks to reconstruct patterns corrupted by noise. A competition neural network is presented that is able to perform digital modulation reception tasks: frequency and phase carrier synchronization; symbol synchronization; systematic compensation of symbol rotation. Some tasks imply post-processing of neural network output. The presented system does not require carrier synchronization with a local oscillator. Same details of the proposed methods are new contributions, which are stressed upon discussion. It was indented to guarantee future implementation of the neural network using programmable logic arrays. It is necessary to limit the proposed architecture size to an acceptable number of logical gates. On the other hand it is necessary to guarantee that each given stimulus vector is fully processed before the next one arrives (assuring real time operation). This work is mainly focused on 4-PSK (or QPSK) modulation, since this kind of modulation is used in a wide range of digital modulation applications (including third generation mobile phones). Generalization possibilities to M-PSK and M-QAM are discussed. Simulation methods were applied to evaluate system performance. Results indicate that the system is able to perform accordingly to objectivesDepartment of Informatics, University of LisbonLourenço, CarlosRepositório da Universidade de LisboaGarcia, João2009-02-10T13:12:37Z2002-112002-11-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://hdl.handle.net/10451/14001porinfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-11-08T15:59:31Zoai:repositorio.ul.pt:10451/14001Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T21:35:53.722037Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital |
title |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital |
spellingShingle |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital Garcia, João Artificial neural networks competition networks pattern recognition telecommunications digital modulation demodulator |
title_short |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital |
title_full |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital |
title_fullStr |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital |
title_full_unstemmed |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital |
title_sort |
Aplicação de Redes Neuronais de Competição à Desmodulação de Sinal em Modulação Digital |
author |
Garcia, João |
author_facet |
Garcia, João |
author_role |
author |
dc.contributor.none.fl_str_mv |
Lourenço, Carlos Repositório da Universidade de Lisboa |
dc.contributor.author.fl_str_mv |
Garcia, João |
dc.subject.por.fl_str_mv |
Artificial neural networks competition networks pattern recognition telecommunications digital modulation demodulator |
topic |
Artificial neural networks competition networks pattern recognition telecommunications digital modulation demodulator |
description |
This work applies a pattern recognition system based on artificial neural networks to the demodulation of digitally modulated signals. It is intended to explore the ability that may be displayed by neural networks to reconstruct patterns corrupted by noise. A competition neural network is presented that is able to perform digital modulation reception tasks: frequency and phase carrier synchronization; symbol synchronization; systematic compensation of symbol rotation. Some tasks imply post-processing of neural network output. The presented system does not require carrier synchronization with a local oscillator. Same details of the proposed methods are new contributions, which are stressed upon discussion. It was indented to guarantee future implementation of the neural network using programmable logic arrays. It is necessary to limit the proposed architecture size to an acceptable number of logical gates. On the other hand it is necessary to guarantee that each given stimulus vector is fully processed before the next one arrives (assuring real time operation). This work is mainly focused on 4-PSK (or QPSK) modulation, since this kind of modulation is used in a wide range of digital modulation applications (including third generation mobile phones). Generalization possibilities to M-PSK and M-QAM are discussed. Simulation methods were applied to evaluate system performance. Results indicate that the system is able to perform accordingly to objectives |
publishDate |
2002 |
dc.date.none.fl_str_mv |
2002-11 2002-11-01T00:00:00Z 2009-02-10T13:12:37Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10451/14001 |
url |
http://hdl.handle.net/10451/14001 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Department of Informatics, University of Lisbon |
publisher.none.fl_str_mv |
Department of Informatics, University of Lisbon |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
_version_ |
1799134258015502336 |