摘要:
A metamaterial comprises a support medium, such as a planar dielectric substrate and a plurality of resonant circuits supported thereby. At least one resonant circuit is a tunable resonant circuit including a conducting pattern and a tunable material, so that an electromagnetic parameter (such as resonance frequency) may be adjusted using an electrical control signal applied to the tunable material.
摘要:
A gradient index lens for electromagnetic radiation includes a dielectric substrate, a plurality of conducting patches supported by the dielectric substrate, the conducting patches preferably being generally square shaped and having an edge length, the edge length of the conducting patches varying with position on the dielectric substrate so as to provide a gradient index for the electromagnetic radiation. Examples include gradient index lenses for millimeter wave radiation, and use with antenna systems.
摘要:
An automotive radar system having a high frequency radio transmitter which generates a radar signal in a known direction. A high frequency radio receiver receives echoes from the radar signal in which each echo represents a reflection of the radar signal from an object. A processor then identifies animate objects, if any, from the received echoes within a range of interest and generates an alert signal for each such identified animate object.
摘要:
A method and system for multiple microphone photoacoustic leak detection and localization. The leak detection technique uses photoacoustic sounds produced by the interaction of a carbon dioxide (CO2) laser turned to 10.6 microns and a photoactive tracer gas, sulfur hexafluoride (SF6), emitted by calibrated leak sources. As the leaked gas is heated by the laser, it expands and launches a photoacoustic sound pulse. The sound pulses generated by the scanning process are recorded across a broad bandwidth by multiple ultra-sensitive microphones. After the photoacoustic pulses arc recorded, the magnitude is compared with background noise measurement at several frequencies for a determination if a leak is present. If the presence of a leak is found, then the location of the leak is determined. The recorded sound is processed by using Matched Field Processing (MFP) as the signal processing technique. The photoacoustic sounds recorded at the microphones are reversed in time through computer simulation that causes the sounds to converge to the apparent point of origin. No synchronization between the acoustic signal processor and the laser scanner is required.
摘要:
A metamaterial microwave lens having an array of electronic inductive capacitive cells in which each cell has an electrically conductive pattern which corresponds to incident electromagnetic radiation as a resonator. At least one cell has a first and second electrical sections insulated from each other and each which section has at least two legs. A static capacitor is electrically connected between one leg of the first section of the cell and one leg of the second section of the cell. A MEMS device is electrically disposed between the other legs of the first and second sections of the cell. The MEMS device is movable between at least two positions in response to an electrical bias between the first and second sections of the cell to vary the index of refraction and resonant frequency of the cell.
摘要:
An apparatus comprises a metamaterial including a first conducting layer, a second conducting layer, and a dielectric layer located between the first conducting layer and the second conducting layer. Each conducting layer has holes formed therethrough, for example as an array of holes formed through the metamaterial. The holes are configured so that the metamaterial has a gradient refractive index at an operational wavelength. The operational wavelength may be an IR or visible wavelength. The apparatus may be an optical element, and for example may have the functionality of a lens or prism through the gradient refractive index. Interfaces may be parallel planar interfaces.
摘要:
A cooling member for withdrawing heat from a heat containing device is disclosed. The cooling member can have a housing with a fluid inlet, a fluid outlet and a plurality of irregular-shaped fins located at least partially therewithin. In addition, a plurality of irregular-shaped and hierarchical branched fluid pathways can be located between the plurality of fins and the housing and/or the plurality of fins can be in physical contact with the heat containing device.
摘要:
An example apparatus comprises an electromagnetic source, such as an antenna, a metamaterial lens, and a reflector. The antenna is located proximate the metamaterial lens, for example supported by the metamaterial lens, and the antenna is operable to generate radiation when the antenna is energized. The reflector is positioned so as to reflect the radiation through the metamaterial lens. The reflector may have a generally concave reflective surface, for example having a parabolic or spherical cross-section. The metamaterial lens may have an area similar to that of the aperture of the reflector. In some examples, the antenna is located proximate a focal point of the reflector, so that a generally parallel beam is obtained after reflection from the reflector.
摘要:
A microwave component having an elongated flexible sheet made of a liquid crystal polymer. A first microwave pattern is printed on one side of the sheet while a second microwave pattern is printed on the other side of the sheet. The first and second patterns are mirror images of each other so that, with the first and second portions of the sheet folded over so that the first portion overlies the second portion, the patterns are aligned with each other and bond together. A margin area of the sheet in between the first and second patterns is then removed to form the microwave component.
摘要:
An active safety system for a machine and a process for operating the active safety system are disclosed. The active safety system an active ultrasonic array having a plurality of ultrasonic transducers. The plurality of ultrasonic transducers can propagate a plurality of sound waves, receive a plurality of echo waves and transform the plurality of echo waves into a plurality of electrical pulses. The plurality of electrical pulses can be transmitted to and received by a three-dimensional imaging circuit. The three-dimensional imaging circuit can generate a 3D image from the plurality of electrical pulses and an electrical control unit can determine a location, size and geometric orientation of the 3D image. The electronic control unit can also provide an occupant safety parameter as a function of the location, size and geometric orientation of the 3D image and transmit the occupant safety parameter or an instruction related to the occupant safety parameter to an occupant safety system and/or an occupant warning system.