Search Results - "Matos, Sergio A."

Feasibility of Radar-Based Detection of Floating Macroplastics at Microwave Frequencies by Felicio, Joao M., Costa, Tomas S., Vala, Mario, Leonor, Nuno, Costa, Jorge R., Marques, Paulo, Moreira, Antonio A., Caldeirinha, Rafael F. S., Matos, Sergio A., Fernandes, Carlos A., Fonseca, Nelson J. G., de Maagt, Peter

“…Plastic marine litter is becoming a major environmental concern. Microwaves (MWs) have potential for remote detection of floating macroplastics operating from…”
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A Geometrical Approach to Duality Transformations for Tellegen Media by Prudencio, Filipa R., Matos, Sergio A., Paiva, Carlos R.

“…Duality transformations are of key importance in the study of Tellegen (i.e., achiral and nonreciprocal biisotropic) media: they often can reduce…”
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Minkowskian Isotropic Media and the Perfect Electromagnetic Conductor by Paiva, C. R., Matos, S. A.

“…The perfect electromagnetic conductor (PEMC) was introduced as an observer-independent "axion medium" that generalizes the concepts of perfect electric…”
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Bessel Beam Generation Using Dielectric Planar Lenses at Millimeter Frequencies by Vaquero, Alvaro F., Pino, Marcos Rodriguez, Arrebola, Manuel, Matos, Sergio A., Costa, Jorge R., Fernandes, Carlos A.

“…In this work a dielectric planar lens is proposed to generate a Bessel beam. The lens works at Ka-band and produces a non-diffraction range within the Fresnel…”
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Dual-Band Dual-Linear-to-Circular Polarization Converter in Transmission Mode Application to [Formula Omitted]-Band Satellite Communications by Naseri, Parinaz, Matos, Sergio A, Costa, Jorge R, Fernandes, Carlos A, Fonseca, Nelson J G

“…Many wireless communication applications such as satellite communications use circularly polarized (CP) signals, with the requirement for easy switching of the…”
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Circular Polarization Wide-Angle Beam Steering at Ka-Band by In-Plane Translation of a Plate Lens Antenna by Lima, Eduardo B., Matos, Sergio A., Costa, Jorge R., Fernandes, Carlos A., Fonseca, Nelson J. G.

“…A simple mechanical beam steering antenna concept is proposed for ground mobile terminals of Ka-band satellite and high altitude platform (HAP) providing…”
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High Gain Dual-Band Beam-Steering Transmit Array for Satcom Terminals at Ka-Band by Matos, Sergio A., Lima, Eduardo B., Silva, Joana S., Costa, Jorge R., Fernandes, Carlos A., Fonseca, Nelson J. G., Mosig, Juan R.

“…Transmit array design is more challenging for dual-band operation than for single band, due to the independent 360° phase wrapping jumps needed at each band…”
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Equivalent Circuit Modeling to Design a Dual-Band Dual Linear-to-Circular Polarizer Surface by Naseri, Parinaz, Costa, Jorge R., Matos, Sergio A., Fernandes, Carlos A., Hum, Sean V.

“…The working principle of a thin dual-band dual-linear to circular polarizer is presented here. This polarizer not only converts incident linearly polarized…”
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Synthesis of Shaped-Beam Radiation Patterns at Millimeter-Waves Using Transmit Arrays by Cruz, Catarina C., Fernandes, Carlos A., Matos, Sergio A., Costa, Jorge R.

“…Transmit arrays have been mostly used for beam collimation applications, either with fixed or scanning beam capability. But transmit arrays can also be used to…”
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Design of Low Profile Transmitarray Antennas with Wide Mechanical Beam Steering at Millimeter-Waves by Vaquero, Alvaro F., Teixeira, Jorge, Matos, Sergio A., Arrebola, Manuel, Costa, Jorge R., Felicio, Joao M., Fernandes, Carlos A., Fonseca, Nelson J. G.

“…Mechanical beam steering using a single Transmitarray (TA) can be a cost-effective solution for a high-gain antenna with wide-angle scanning. Elevation…”
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Generalized Risley Prism for Beam-Steering Transmit Arrays With Reduced Grating Lobes by Matos, Sergio A., Fonseca, Nelson J. G., Serra, Joao C., Felicio, Joao M., Costa, Jorge R., Fernandes, Carlos A.

“…Wide-angle beam steering is a fundamental requisite for the new generation of millimeter-wave communication systems. Mechanical scanning using two transmit…”
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Efficient Evaluation of Gradient Transmit-Arrays Through an Equivalent Dispersive Dielectric Description by Naseri, Parinaz, Matos, Sergio A., Lima, Eduardo B., Costa, Jorge R., Fernandes, Carlos A., Fonseca, Nelson J. G.

“…The growing popularity of transmit-arrays (TAs) for various antenna applications is calling for effective analysis and optimization methods. TAs are, usually,…”
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Study of Environmentally-Friendly Radomes Using Cork-Rubber Composites for 5G Backhaul Links at E-band by Felicio, Joao M., Motta-Cruz, Eduardo, Costa, Jorge R., Matos, Sergio A., Fernandes, Carlos A.

“…Polymer-based materials face increasing limitations imposed by the U.S.A. and European legislation due to their environmental impact, namely carbon footprint…”
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Surface and proper leaky-modes in a lossless grounded pseudochiral omega slab by Matos, Sérgio A., Paiva, Carlos R., Barbosa, Afonso M.

“…Surface and proper leaky modes guided by a grounded pseudochiral omega slab are studied. A new physical result is found: proper leaky modes may occur in a…”
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Evaluation of a Dielectric-Only Transmitarray for Generating Multi-Focusing Near-Field Spots Using a Cluster of Feeds in the Ka-Band by Vaquero, Álvaro F, Pino, Marcos Rodríguez, Arrebola, Manuel, Matos, Sérgio A, Costa, Jorge R, Fernandes, Carlos A

“…A transmitarray antenna is evaluated to generate a multi-focusing spot area in the Fresnel region of the antenna in the Ka-band. The antenna is designed to…”
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3-D-Printed Transmit-Array Antenna for Broadband Backhaul 5G Links at V-Band by Matos, Sergio A., Teixeira, Jorge P., Costa, Jorge R., Fernandes, Carlos A., Nachabe, Nour, Luxey, Cyril, Titz, Diane, Gianesello, Frederic, del Rio, Carlos, Arboleya, Ana, Garnero, Jean-Philippe, Vizzari, Jean-Francois

“…The low cost and compactness of transmit-array antennas (TAs) make them attractive for 5G backhaul links. However, the TA advantage is less obvious when…”
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Small-Scale Passive Millimetre-Wave Imaging Measurements for Marine Litter Detection at W-Band by Vala, Mario, Felicio, Joao M., Costa, Tomas S., Leonor, Nuno, Costa, Jorge R., Marques, Paulo, Moreira, Antonio A., Matos, Sergio A., Caldeirinha, Rafael F. S., Fernandes, Carlos A., Fonseca, Nelson J. G., De Maagt, Peter

“…In this study, we explore the possibility of employing passive millimetre-wave imaging (PMMWI) as a means for remotely detecting plastic marine litter. We…”
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Detection of Low Permittivity Floating Plastic Sheets at Microwave Frequencies by Da Costa, Tomas Soares, Felicio, Joao M., Vala, Mario, Leonor, Nuno, Costa, Jorge R., Marques, Paulo, Moreira, Antonio A., Caldeirinha, Rafael, Matos, Sergio A., Fernandes, Carlos A., Fonseca, Nelson J.G., de Maagt, Peter

“…Microwaves are surfacing in remote sensing as a viable or complementary technology to optical techniques for the detection and monitoring of floating plastic…”
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Applying Massively Parallel Computing to Multiscale Ka Dual-Band Transmit-Array Analysis Using FETI-2LM by Barka, Andre, Matos, Sergio A., Costa, Jorge R., Fernandes, Carlos A., Chreim, Hassan

“…Transmit-arrays (TAs) are a popular cost-effective solution for high-gain antennas at millimeter waves. The design of these antennas relies on the fine tuning…”
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On the Feasibility of Using Passive mm-Wave Imaging for Marine Litter Detection at the W-band by Vala, Mario, Felicio, Joao M., Da Costa, Tomas Soares, Leonor, Nuno, Costa, Jorge R., Marques, Paulo, Moreira, Antonio A., Matos, Sergio A., Caldeirinha, Rafael F. S., Fernandes, Carlos A., Fonseca, Nelson J. G., de Maagt, Peter

“…Large research effort is appearing in the literature on remote detection of plastic marine litter, using optical instruments, and lately microwaves. We present…”
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