Zobrazeno 1 - 10
of 145
pro vyhledávání: '"Nelson J. G. Fonseca"'
Publikováno v:
IEEE Open Journal of Antennas and Propagation, Vol 5, Iss 1, Pp 58-66 (2024)
In this paper, a novel dual-slant polarized three-dimensional (3D) periodic Luneburg lens with a diameter of 390 mm ( $4.6\lambda _{0}$ at 3.55 GHz) is presented. Copper-plated cubes with truncated corners are placed in a body-centered cubic (BCC) la
Externí odkaz:
https://doaj.org/article/3acc58d3ec4347e3b5040e62f6471393
Publikováno v:
IEEE Journal of Microwaves, Vol 3, Iss 4, Pp 1199-1211 (2023)
This article provides for the first time a detailed discussion of the optimal assignment of adjacent output phase differences in terms of matrix performance out of all possible combinations in generalized one-dimensional parallel switching matrices w
Externí odkaz:
https://doaj.org/article/99e2f63eb6e54b22972f4829bb268c3c
Publikováno v:
IEEE Access, Vol 11, Pp 74239-74249 (2023)
This paper presents a design of a two-dimensional (2-D) $6\times 4$ -way hollow waveguide beam-switching matrix working at 28.25 GHz, with a fractional bandwidth of 7.1%. It is the first time that a 2-D one-body hollow waveguide beam-switching matrix
Externí odkaz:
https://doaj.org/article/3d1b3542da1141b1b7b7ab1d6999ad26
Publikováno v:
IEEE Journal of Microwaves, Vol 3, Iss 2, Pp 800-814 (2023)
3D-printing is leading to a major transformation in many industrial and application sectors, ranging from medical to aerospace. In the space sector, 3D-printing has firstly been adopted for the development of structural and thermal parts, such as bra
Externí odkaz:
https://doaj.org/article/7255d0c991174c1882b99436185cf373
Autor:
Nicola Bartolomei, Darwin Blanco, Francois Doucet, Etienne Girard, Herve Legay, Nelson J. G. Fonseca, Ronan Sauleau, Mauro Ettorre
Publikováno v:
IEEE Access, Vol 11, Pp 4602-4614 (2023)
This work presents a full metal circularly-polarized lens-like antenna for Satcom applications at Ka-band. The antenna is composed of two continuous parallel plate waveguide (PPW) quasi-optical beamformers (QOBF), feeding an array of septum polarizer
Externí odkaz:
https://doaj.org/article/8b1f595cdf6246978eb422467d37155a
Publikováno v:
Scientific Reports, Vol 12, Iss 1, Pp 1-14 (2022)
Abstract Electromagnetic linear-to-circular polarization converters with wide- and multi-band capabilities can simplify antenna systems where circular polarization is required. Multi-band solutions are attractive in satellite communication systems, w
Externí odkaz:
https://doaj.org/article/4d6f4511e5a34b1799e161c55552ef6e
Publikováno v:
Nature Communications, Vol 13, Iss 1, Pp 1-12 (2022)
A double-layer lens consists of a first gradient-index/geodesic profile in an upper waveguide, partially surrounded by a mirror that reflects the wave into a lower guide where there is a second profile. A family of such lens profiles are derived.
Externí odkaz:
https://doaj.org/article/3ee42a585d9e4d229cb21e888da7b981
Autor:
Tobias Chaloun, Luigi Boccia, Emilio Arnieri, Michael Fischer, Vaclav Valenta, Nelson J. G. Fonseca, Christian Waldschmidt
Publikováno v:
IEEE Journal of Microwaves, Vol 2, Iss 4, Pp 545-581 (2022)
Satellite, fifth generation (5G), and sixth generation (6G) mobile communication systems operating at micro- and millimeter wave frequencies are an essential pillar in advanced network architectures for high-throughput low latency services. The decis
Externí odkaz:
https://doaj.org/article/fcbbb134cacb45e88d2a755facf70767
Publikováno v:
IEEE Journal of Microwaves, Vol 2, Iss 4, Pp 678-689 (2022)
Septum polarizers have been used in waveguide systems for over 50 years and are very popular in communication satellites operating in circular polarization. With the progress of computational electromagnetics and computer hardware, combined with adva
Externí odkaz:
https://doaj.org/article/0a98df68486541a6bc1258fef73b188c
Publikováno v:
Communications Physics, Vol 4, Iss 1, Pp 1-10 (2021)
Spherically-symmetric lenses can create sharp virtual images, but a general expression for their refractive index profiles had not yet been developed. Here, this expression is provided via analogy between classical mechanics and geometrical optics, y
Externí odkaz:
https://doaj.org/article/589ca8132c2e489280a00b0fabf289b0