摘要:
Described embodiments include an antenna, method, and an apparatus. The antenna includes a sub-Nyquist complex-holographic aperture configured to define at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface with tangential wavenumbers up to 2&pgr; over the aperture element spacing (k_apt=2&pgr;/a).
摘要:
Described embodiments include an antenna, method, and an apparatus. The antenna includes a sub-Nyquist complex-holographic aperture configured to define at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface with tangential wavenumbers up to 2&pgr; over the aperture element spacing (k_apt=2&pgr;/a).
摘要:
Described embodiments include an antenna, method, and an apparatus. The antenna includes a sub-Nyquist complex-holographic aperture configured to define at least two selectable, arbitrary complex radiofrequency electromagnetic fields on a surface with tangential wavenumbers up to 2&pgr; over the aperture element spacing (k_apt=2&pgr;/a).
摘要:
A method and apparatus for processing a terahertz frequency electromagnetic beam are disclosed. For example, the method receives the terahertz frequency electromagnetic beam via a metamaterial having a plurality of addressable magnetic elements, where a resonant frequency of each of the plurality of addressable magnetic elements is capable of being programmably changed via an adjustment, and activates selectively a subset of the plurality of addressable magnetic elements to manipulate the terahertz frequency electromagnetic beam.
摘要:
An implantable medical device comprises an antenna configured for wirelessly receiving energy of a first frequency from an external device, electronic circuitry configured for performing a function in response to the receipt of the received energy, and a biocompatible housing containing the electronic circuitry and antenna. The housing includes a substrate structure and a two-dimensional array of elements disposed on the substrate structure. The array of elements and substrate structure are arranged in a manner that creates a frequency selective surface capable of reflecting at least a portion of energy of a second frequency incident on the housing, while passing at least a portion of energy of the first frequency incident on the housing to the antenna.
摘要:
An antenna assembly for a wireless communication device includes a substrate of dielectric material that has opposing first and second surfaces. A ground plane formed by a layer of electrically conductive material on the first surface. An antenna with a physical length is disposed on the substrate. At least one metal-dielectric structure is disposed on the substrate. The metal-dielectric structures resonate so as to interact with the antenna and thereby alter the effective electrical length of the antenna. That interaction causes the antenna to function as though it had a greater physical length. In one embodiment, that interaction enables an antenna ,that is shorter than one-fourth the wavelength of a radio frequency signal applied thereto, to function as through the physical length of the antenna was one-fourth that wavelength.
摘要:
A method and apparatus for processing a terahertz frequency electromagnetic beam are disclosed. For example, the method receives the terahertz frequency electromagnetic beam via a metamaterial having a plurality of addressable magnetic elements, where a resonant frequency of each of the plurality of addressable magnetic elements is capable of being programmably changed via an adjustment, and activates selectively a subset of the plurality of addressable magnetic elements to manipulate the terahertz frequency electromagnetic beam.
摘要:
An antenna comprises a plurality of re-radiating elements arranged in at least one plane being parallel to a fixed surface. The arrangement is adapted such that electromagnetic radiation emitted from the re-radiating elements in response to electromagnetic radiation arriving from a predetermined direction interferes constructively at a feed location. Additionally, the antenna comprises a feed provided at the feed location. In a method of manufacturing an antenna, the arrangement of the plurality of re-radiating elements may be calculated and the re-radiating elements can be provided in the at least one plane substantially parallel to the substrate. An apparatus for manufacturing an antenna may comprise a data processor adapted to calculate the arrangement of the plurality of re-radiating elements and means for forming the plurality of re-radiating elements.
摘要:
A grating comprising a plurality of substantially parallel members having a conducting surface of depth L, separated by a dielectric layer gap, and having of pitch μg and where L>16μg. The members are preferably metallic or comprise metallic foil covered plastic. The gap may be filled wholly or partially with dielectric material including liquid crystal whose refractive index can be controlled by suitable application of voltage across the gap.
摘要:
L'invention a pour objet un dispositif à surface sélective en fréquence comportant au moins un réseau (1) d'éléments conducteurs constituant des motifs élémentaires (2). Selon l'invention le dispositif comporte des moyens de couplage (4) entre les éléments conducteurs, sélectionnés et commandés par des moyens de commande (3) de manière à modifier la dimension apparente des motifs rendant ainsi le réseau sélectif accordable dans une large gamme de fréquences, ces moyens de couplage (4) comportant une première série de composants électroniques (44), une deuxième série de composants électroniques (45) permettant d'actionner les composants de la première série et de contrôler leur conduction, les composants (45) de la deuxième série étant reliés par au moins un fil d'adressage (41, 42) aux moyens de commande (3).