Listar por tema "Metamaterials"
Mostrando ítems 1-20 de 46
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A study of super-oscillatory lenses of high frecuencies using metamaterials
The first part of this work deals with the design, numerical demonstration and experimental characterization of an ultra-thin super-oscillatory lens (SOL) based on metamaterials (MTMs) at the Terahertz range, with a ... -
Accurate circuit modeling of fishnet structures for negative-index-medium applications
Metallic plates with a two-dimensional (2D) periodic distribution of sub-wavelength apertures are known to exhibit extraordinary transmission of electromagnetic waves. Stacking two or more of such plates gives place to the ... -
Advanced metamaterials for high resolution focusing and invisibility cloaks
Los metamateriales, descendientes de los dieléctricos artificiales, tienen parámetros electromagnéticos inusuales y proporcionan más posibilidades que los dieléctricos naturales para el control de la propagación de la luz. ... -
Blind spot mitigation in phased array antenna using metamaterials
In this work, a metaradome based on a fakir’s bed of nails is designed and tested in order to suppress the blind directions of a 100-element antenna array. The antenna is a microstrip array designed to operate in X-band. ... -
Compact pillbox reflector based on geodesic lens
We propose a pillbox antenna in combination with a geodesic lens at 60 GHz. The antenna is implemented in a dual-layer parallel plate waveguide. The waves from a geodesic lens in a first layer, after being reflected by a ... -
Coupling in metamaterial structures and devices
(2023) Tesis doctoral / Doktoretza tesiaEn esta tesis se abordan algunos de los retos de las comunicaciones actuales desde el punto de vista de diseño de dispositivos. La tesis se estructura en tres capítulos: En el primero de ellos se presentan las líneas ... -
Desfasadores para microstrip empleando metamateriales
In this paper an application of LH materials at microwave frequencies (10GHz) is presented. A compact quarter-wave impedance transformer is proposed using alternating sections of left handed media (LHM) and conventional ... -
Design of a planar meta-surface based on dipoles and wires for antenna applications
In this paper, the design of a planar meta-surface based on dipoles and wires is presented. The unit cell is formed by three independent layers, which contain two parallel dipoles and one wire. The behaviour of these ... -
Design of multi-layered radiative cooling structures using evolutionary algorithms
In this work we present a novel way to design thinfilm radiative cooling metamaterials based on genetic algorithms. Three simulations with different design constraints have been done, resulting in three structures that ... -
Design of terahertz sensors based on metasurfaces for fungal infection detection
El trabajo propuesto trata sobre el diseño de sensores en la banda de terahercios para la detección de “thin films” y microorganismos, en particular de hongos. En primer lugar, se ha realizado un estudio profundo de ... -
Dipolos y metamateriales: mejora de las características de radiación
In this work, pass band properties of Left Handed Media (LHM) are demonstrated. These properties have been used in order to make a LHM super-substrate that is put over a dipole antenna. This super-substrate is going to ... -
Diseño, simulación, fabricación y medida de lentes de metamaterial acopladas a antenas de bocina
En este proyecto fin de carrera se presenta un sistema formado por una antena de bocina y una lente metálica de metamaterial basada en transmisión extraordinaria. Como ya se ha demostrado en el pasado, la aplicación de ... -
Electroinductive waves in chain of complementary metamaterial elements
Electronductive waves supported by chains of resonators drilled on a metallic plate are presented. Propagation of energy comes as a consequence of the electric coupling between these resonators. Therefore, these waves ... -
Enhancing the infrared and visible emission properties of calcium silicate hydrate for radiative cooling using metamaterials
Two periodic structures composed of metal cylinders with different orientations are used to improve the solar reflection of calcium silicate hydrate (CSH) while maintaining its atmospheric emission. Interesting effects ... -
Epsilon-near-zero metalenses operating in the visible
Several converging lenses working in the permittivity near to zero (ENZ) regime at optical frequencies are designed using an array of metal-dielectric-metal plasmonic waveguides. These plasmonic waveguides show a dispersive ... -
Estudio sobre resonadores en tecnología microstrip como sensor de medida de grosor de materiales a 24GHz
Diversas aplicaciones industriales requieren de la caracterización y medición de materiales con alta precisión. En las últimas décadas se han investigado métodos para realizar dichas mediciones ... -
Experimental demonstration of a millimeter-wave metallic ENZ lens based on the energy squeezing principle
The performance of an epsilon-near zero (ENZ) plano-concave lens is experimentally demonstrated and verified at the D-band of the millimeter-waves. The lens is comprised of an array of narrow metallic waveguides near cut-off ... -
Experimental demonstration of deeply subwavelength dielectric sensing with epsilon-near-zero (ENZ) waveguides
In this Letter, an all metallic sensor based on ε-near-zero (ENZ) metamaterials is studied both numerically and experimentally when working at microwave frequencies. To emulate an ENZ medium, a sensor is made by using a ... -
Experimental demonstration of metamaterials application for mitigating scan blindness in phased array antennas
This paper presents two metamaterial-inspired solutions to mitigate the scan blindness effects in a phased array antenna. In the first solution, portions of a bed of nails are introduced in the radome to prevent the excitation ... -
Experimental realization of an epsilon-near-zero graded-index metalens at terahertz frequencies
The terahertz band has been historically hindered by the lack of efficient generators and detectors, but a series of recent breakthroughs have helped to effectively close the “terahertz gap.” A rapid development of terahertz ...