Zobrazeno 1 - 10
of 100
pro vyhledávání: '"Fernando J. S. Moreira"'
Publikováno v:
Journal of Microwaves, Optoelectronics and Electromagnetic Applications, Vol 23, Iss 3 (2024)
Abstract In the present work an analytical formulation to synthesize non-uniform phase distributions at cylindrical apertures is described. Assuming three distinct amplitude distributions, the respective phases are established to provide cosecant-squ
Externí odkaz:
https://doaj.org/article/6597d4b6ada54315bb557ebc9219460f
Publikováno v:
International Journal of Antennas and Propagation, Vol 2018 (2018)
This work discusses an alternative geometrical optics (GO) technique to synthesize omnidirectional dual-reflector antennas with uniform aperture phase distribution together with an arbitrary main-beam direction for the antenna radiation pattern. Sub-
Externí odkaz:
https://doaj.org/article/23265970aa1749bbb3be8915eae9607a
Autor:
Diego Tami, Cássio G. Rego, Dinael Guevara, Andrés Navarro, Fernando J. S. Moreira, Jordi Giménez, Hernan G. Triana
Publikováno v:
International Journal of Antennas and Propagation, Vol 2018 (2018)
We discuss three sets of heuristic coefficients used in uniform theory of diffraction (UTD) to characterize the electromagnetic scattering in realistic urban scenarios and canonical examples of diffraction by lossy conducting wedges using the three s
Externí odkaz:
https://doaj.org/article/1e420bffbf0e4df2a3bc47ea014eca72
Publikováno v:
International Journal of Antennas and Propagation, Vol 2016 (2016)
This work investigates a novel numerical procedure for the solution of an exact formulation for the Geometrical Optics synthesis of a single reflector antenna by simultaneously imposing Snell’s Law and Conservation of Energy in a tube of rays, yiel
Externí odkaz:
https://doaj.org/article/d108fe884dc6451286b85c0751f52105
Publikováno v:
International Journal of Antennas and Propagation, Vol 2012 (2012)
This paper presents a formulation for shaping the main reflector of an axis-symmetric dual-reflector antenna designed to offer an omnidirectional coverage with an arbitrary radiation pattern in the vertical plane. The subreflector is generated by an
Externí odkaz:
https://doaj.org/article/871a7d3ec63d48d187213d5aec89144f
Publikováno v:
Journal of Microwaves, Optoelectronics and Electromagnetic Applications, Vol 19, Iss 2, Pp 177-190
Abstract This work investigates an alternative numerical scheme for the solution of an exact formulation based on Geometrical Optics (GO) principles to synthesize offset dual reflector antennas. The technique is suited to solve a second-order nonline
Externí odkaz:
https://doaj.org/article/a66b18989b8b42d5b559cef367b14918
Publikováno v:
International Journal for Numerical Methods in Engineering. 122:3141-3170
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::f891d780d4325afd8a158d8198161466
https://doi.org/10.1002/nme.6647
https://doi.org/10.1002/nme.6647
Publikováno v:
Vietnam Journal of Mechanics. 42:209-237
When the method of finite spheres is used for the solution of time-harmonic acoustic wave propagation problems in nonhomogeneous media, a mixed (or saddle-point) formulation is obtained in which the unknowns are the pressure fields and the Lagrange m
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::2dce107bff290653e7511a080da95249
https://doi.org/10.15625/0866-7136/15336
https://doi.org/10.15625/0866-7136/15336
Publikováno v:
IET Microwaves, Antennas & Propagation. 14:1310-1315
This work presents a new technique for the geometrical optics (GO) shaping of axisymmetric dual-reflector antennas. Both reflectors' generatrices are shaped by the continuous concatenation of conic sections, suited to provide simultaneous control of
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e7217b6138060532715dece8a92be9bf
https://doi.org/10.1049/iet-map.2020.0156
https://doi.org/10.1049/iet-map.2020.0156
Autor:
Fernando J. S. Moreira, Joyce Lopes
Publikováno v:
Cadernos de Campo, Iss 28, Pp 17-26 (2020)
Expoente da Semiótica de orientação francesa no Brasil, Diana Luz Pessoa de Barros analisa, nesta entrevista a Fernando Moreira e a Joyce Lopes, estratégias enunciativas da nova extrema direita que passaram a marcar os discursos políticos e soci
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::30da86f0d5123c6ec52d01e18947379b
https://periodicos.fclar.unesp.br/cadernos/article/view/14184/9652
https://periodicos.fclar.unesp.br/cadernos/article/view/14184/9652