摘要:
A photonic bandgap antenna (PBA) (10') utilizes a periodic bandgap material (PBM), which is essentially a dielectric, to transmit, receive, or communicate electromagnetic radiation encoded with information. Further, a photonic bandgap transmission line (PBTL) (10") can also be constructed with the PBM. Because the PBA (10') and PBTL (10") do not utilize metal, the PBA (10') and PBTL (10") can be used in harsh environments, such as those characterized by high temperature and/or high pressure, and can be easily built into a dielectric structure such as a building wall or roof. Further, the PBA (10') and PBTL (10") inhibit scattering by incident electromagnetic radiation at frequencies outside those electromagnetic frequencies in the bandgap range associated with the PBM.
摘要:
The present invention provides a fragmented aperture antenna. The antenna includes a planar layer having a plurality of conductive and substantially non-conductive areas. Each area has a periphery that extends along a grid of first and second sets of parallel lines so that each area comprises one or more contiguous elements defined by the parallel lines. The locations of the conducting materials in the fragmented aperture antenna are determined by a multi-stage optimization procedure that tailors the performance of the antenna to a particular application. The resulting configuration and arrangement of conductive and substantially non-conductive areas enable communication of electromagnetic energy wirelessly in a specific direction to the planar layer when an electrical connection is made to at least one of the conductive areas.
摘要:
Various examples of methods and systems are disclosed for non-contact determination of coating thickness. In one example, among others, a method includes illuminating a surface having a layer of a coating material with electromagnetic (EM) energy transmitted at two or more frequencies, obtaining measured reflection data from reflected EM energy, and matching the measured reflection data to modeled reflection data of a reflection model based upon minimization of an error between the measured reflection data and the modeled reflection data to determine a measured thickness of the layer. In another example, a system includes a probe configured to illuminate an area of the surface including a layer of a coating material with EM energy and receive reflected EM energy, and a processing device configured to determine a measured thickness of the layer based upon minimization of an error between measured reflection data and modeled reflection data.
摘要:
A thin-film bulk acoustic wave delay line device providing true-time delays and a method of fabricating same. An exemplary device can comprise several thin-film layers including thin-film transducer layers, thin-film delay layers, and stacks of additional thin-film materials providing acoustic reflectors and matching networks. The layer material selection and layer thicknesses can be controlled to improve impedance matching between transducers and the various delay line materials. For example, the transducer layers and delay layers can comprise piezoelectric and amorphous forms of the same material. The layers can be deposited on a carrier substrate using standard techniques. The device can be configured so that mechanical waves propagate solely within the thin films, providing a substrate-independent device. The device, so constructed, can be of a small size, e.g. 40 μm per side, and capable of handling high power levels, potentially up to 20 dBm, with low insertion loss of approximately 3 dB.
摘要:
Various examples are provided for fragmented aperture antennas. In one example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements, where positioning of the conducting elements in adjacent rows are offset based upon a fixed skew angle. In another example, a fragmented aperture antenna includes a two-dimensional lattice comprising a combination of first and second geometric conducting elements, where a second geometric conducting element provides a connection between adjacent sides of diagonally adjacent first geometric conducting elements. In another example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements having a single common non-rectangular shape, where the conducting elements interleave in a digitated fashion. Diagonally adjacent conducting elements overlap along a portion of adjacent edges of the diagonally adjacent conducting elements.
摘要:
Various examples are provided for fragmented aperture antennas. In one example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements, where positioning of the conducting elements in adjacent rows are offset based upon a fixed skew angle. In another example, a fragmented aperture antenna includes a two-dimensional lattice comprising a combination of first and second geometric conducting elements, where a second geometric conducting element provides a connection between adjacent sides of diagonally adjacent first geometric conducting elements. In another example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements having a single common non-rectangular shape, where the conducting elements interleave in a digitated fashion. Diagonally adjacent conducting elements overlap along a portion of adjacent edges of the diagonally adjacent conducting elements.
摘要:
Various examples of methods and systems are disclosed for non-contact determination of coating thickness. In one example, among others, a method includes illuminating a surface having a layer of a coating material with electromagnetic (EM) energy transmitted at two or more frequencies, obtaining measured reflection data from reflected EM energy, and matching the measured reflection data to modeled reflection data of a reflection model based upon minimization of an error between the measured reflection data and the modeled reflection data to determine a measured thickness of the layer. In another example, a system includes a probe configured to illuminate an area of the surface including a layer of a coating material with EM energy and receive reflected EM energy, and a processing device configured to determine a measured thickness of the layer based upon minimization of an error between measured reflection data and modeled reflection data.
摘要:
A thin-film bulk acoustic wave delay line device providing true-time delays and a method of fabricating same. An exemplary device can comprise several thin-film layers including thin-film transducer layers, thin-film delay layers, and stacks of additional thin-film materials providing acoustic reflectors and matching networks. The layer material selection and layer thicknesses can be controlled to improve impedance matching between transducers and the various delay line materials. For example, the transducer layers and delay layers can comprise piezoelectric and amorphous forms of the same material. The layers can be deposited on a carrier substrate using standard techniques. The device can be configured so that mechanical waves propagate solely within the thin films, providing a substrate-independent device. The device, so constructed, can be of a small size, e.g. 40 μm per side, and capable of handling high power levels, potentially up to 20 dBm, with low insertion loss of approximately 3 dB.