The use of instantaneous phase for improving sparse arrays images
Autor(a) principal: | |
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Data de Publicação: | 2013 |
Outros Autores: | , , , |
Tipo de documento: | Artigo de conferência |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1109/ULTSYM.2013.0250 http://hdl.handle.net/11449/111864 |
Resumo: | Sparse arrays have pitch larger than half-wavelength (lambda/2) and there is a reduced number of elements in comparison with a full-populated array. Consequently, there is a reduction in cost, data acquisition and processing. However, conventional beamforming techniques result in large side and grating lobes, and consequently in image artifacts. In this work the instantaneous phase of the signals is used in a beamforming technique instead of the instantaneous amplitudes to improve images obtained from sparse arrays configurations. A threshold based on a statistical analysis and the number of signals used for imaging is applied to each pixel, in order to determine if that pixel is related to a defect or not. Three sets of data are used to evaluate the technique, considering medical and non-destructive testing: a simulated point spread function, a medical phantom and an aluminum plate with 2 lambda-, 7 lambda- and lambda-pitch, respectively. The conventional amplitude image is superposed by the image improved by the instantaneous phase, increasing the reflectors detectability and reducing artifacts for all cases, as well as dead zone for the tested plate. |
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The use of instantaneous phase for improving sparse arrays imagesSparse arrays have pitch larger than half-wavelength (lambda/2) and there is a reduced number of elements in comparison with a full-populated array. Consequently, there is a reduction in cost, data acquisition and processing. However, conventional beamforming techniques result in large side and grating lobes, and consequently in image artifacts. In this work the instantaneous phase of the signals is used in a beamforming technique instead of the instantaneous amplitudes to improve images obtained from sparse arrays configurations. A threshold based on a statistical analysis and the number of signals used for imaging is applied to each pixel, in order to determine if that pixel is related to a defect or not. Three sets of data are used to evaluate the technique, considering medical and non-destructive testing: a simulated point spread function, a medical phantom and an aluminum plate with 2 lambda-, 7 lambda- and lambda-pitch, respectively. The conventional amplitude image is superposed by the image improved by the instantaneous phase, increasing the reflectors detectability and reducing artifacts for all cases, as well as dead zone for the tested plate.Univ Estadual Paulista, Fac Engn Ilha Solteira, BR-15385000 Ilha Solteira, SP, BrazilUniv Estadual Paulista, Fac Engn Ilha Solteira, BR-15385000 Ilha Solteira, SP, BrazilIeeeUniversidade Estadual Paulista (Unesp)Prado, V. T. [UNESP]Higuti, R. T. [UNESP]Kitano, C. [UNESP]Martinez-Graullera, O.IEEE2014-12-03T13:09:02Z2014-12-03T13:09:02Z2013-01-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/conferenceObject966-969http://dx.doi.org/10.1109/ULTSYM.2013.02502013 Ieee International Ultrasonics Symposium (ius). New York: Ieee, p. 966-969, 2013.http://hdl.handle.net/11449/11186410.1109/ULTSYM.2013.0250WOS:000336665300247640533951088320328834403518951670000-0003-4201-56170000-0001-6320-755XWeb of Sciencereponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPeng2013 Ieee International Ultrasonics Symposium (ius)info:eu-repo/semantics/openAccess2022-01-11T17:19:37Zoai:repositorio.unesp.br:11449/111864Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462022-01-11T17:19:37Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
The use of instantaneous phase for improving sparse arrays images |
title |
The use of instantaneous phase for improving sparse arrays images |
spellingShingle |
The use of instantaneous phase for improving sparse arrays images Prado, V. T. [UNESP] |
title_short |
The use of instantaneous phase for improving sparse arrays images |
title_full |
The use of instantaneous phase for improving sparse arrays images |
title_fullStr |
The use of instantaneous phase for improving sparse arrays images |
title_full_unstemmed |
The use of instantaneous phase for improving sparse arrays images |
title_sort |
The use of instantaneous phase for improving sparse arrays images |
author |
Prado, V. T. [UNESP] |
author_facet |
Prado, V. T. [UNESP] Higuti, R. T. [UNESP] Kitano, C. [UNESP] Martinez-Graullera, O. IEEE |
author_role |
author |
author2 |
Higuti, R. T. [UNESP] Kitano, C. [UNESP] Martinez-Graullera, O. IEEE |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade Estadual Paulista (Unesp) |
dc.contributor.author.fl_str_mv |
Prado, V. T. [UNESP] Higuti, R. T. [UNESP] Kitano, C. [UNESP] Martinez-Graullera, O. IEEE |
description |
Sparse arrays have pitch larger than half-wavelength (lambda/2) and there is a reduced number of elements in comparison with a full-populated array. Consequently, there is a reduction in cost, data acquisition and processing. However, conventional beamforming techniques result in large side and grating lobes, and consequently in image artifacts. In this work the instantaneous phase of the signals is used in a beamforming technique instead of the instantaneous amplitudes to improve images obtained from sparse arrays configurations. A threshold based on a statistical analysis and the number of signals used for imaging is applied to each pixel, in order to determine if that pixel is related to a defect or not. Three sets of data are used to evaluate the technique, considering medical and non-destructive testing: a simulated point spread function, a medical phantom and an aluminum plate with 2 lambda-, 7 lambda- and lambda-pitch, respectively. The conventional amplitude image is superposed by the image improved by the instantaneous phase, increasing the reflectors detectability and reducing artifacts for all cases, as well as dead zone for the tested plate. |
publishDate |
2013 |
dc.date.none.fl_str_mv |
2013-01-01 2014-12-03T13:09:02Z 2014-12-03T13:09:02Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/conferenceObject |
format |
conferenceObject |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://dx.doi.org/10.1109/ULTSYM.2013.0250 2013 Ieee International Ultrasonics Symposium (ius). New York: Ieee, p. 966-969, 2013. http://hdl.handle.net/11449/111864 10.1109/ULTSYM.2013.0250 WOS:000336665300247 6405339510883203 2883440351895167 0000-0003-4201-5617 0000-0001-6320-755X |
url |
http://dx.doi.org/10.1109/ULTSYM.2013.0250 http://hdl.handle.net/11449/111864 |
identifier_str_mv |
2013 Ieee International Ultrasonics Symposium (ius). New York: Ieee, p. 966-969, 2013. 10.1109/ULTSYM.2013.0250 WOS:000336665300247 6405339510883203 2883440351895167 0000-0003-4201-5617 0000-0001-6320-755X |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
2013 Ieee International Ultrasonics Symposium (ius) |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
966-969 |
dc.publisher.none.fl_str_mv |
Ieee |
publisher.none.fl_str_mv |
Ieee |
dc.source.none.fl_str_mv |
Web of Science reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
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1803046975659048960 |