160 results about "Coaxial antenna" patented technology

An antenna feed system includes a plurality of RF horn antennas (201, 202) for operating on a plurality of RF frequency bands. A first one of the feed horns (202) can have a boresight axis and is configured for operating at a first one of the frequency bands. A second one of the feed horns (201) is positioned coaxially within the first one of the feed horns (202) and is configured for operating at least at a second one of the frequency bands. Further, the first one of the feed horns (202) is a corrugated horn that has a plurality of corrugations (204) formed on an interior surface defining a profile. The profile extends substantially from a throat (205) of the first feed horn and along a tapered portion of the first feed horn. The profile substantially minimizes an interaction of the corrugations with the second feed horn.

Apparatus for detecting vulnerable plaques embedded in the wall of a patient's blood vessel includes an intravascular catheter containing a microwave antenna, an extra-corporeal radiometer having a signal input, a reference input and an output, a cable for electrically connecting the antenna to the signal input, and a device for applying an indication of the patient's normal tissue temperature to the reference input so that when the catheter is moved along the vessel, the locations of the vulnerable plaques are reflected in a signal from the output as thermal anomalies due to the higher emissivity of the vulnerable plaques as compared to the normal tissue. A second embodiment of the apparatus has two coaxial antennas in the catheter serving two radiometers. One measures the temperature at locations in the vessel wall, the other measures the temperature at the surface. By subtracting the two signals, the locations of vulnerable plaque may be visualized. The apparatus employs a special diplexer for separating the signals from the two antennas and a method of detecting and possibly destroying the plaques is also disclosed.

An on-board radar apparatus includes an antenna unit configured by combining one of a lens and a reflector, and a plurality of antenna elements, a transmission and reception unit configured to emit a radio wave using, for at least one of transmission or reception, a partial antenna of a plurality of patterns configured by the antenna elements that are part of the plurality of antenna elements, and to receive a reflection wave obtained by reflection of the radio wave from an object, and a detection unit configured to detect the object based on the reflection wave received by the transmission and reception unit.

An improved antenna for microwave ablation uses a triaxial design which reduces reflected energy allowing higher power ablation and / or a smaller diameter feeder line to the antenna.

A semi-coaxial horn antenna transmits and receives electromagnetic waves, including impulse radio waves. The antenna includes an inner conductor that is surrounded by a cone-shaped dielectric, and an outer conductor that is conformally attached to the cone shaped dielectric. In embodiments, the inner conductor is a hollow metallic cylinder that is able to slide over a separate metal shaft, which may be part of a portable hand-tool device. The dielectric constant of the cone shaped dielectric may be selected to match a target medium. The outer conductor has a cross-section that is substantially an arc shape, and defines a sector angle phi that determines an impedance along the length of the antenna.

An improved antenna for microwave ablation uses a triaxial design which reduces reflected energy allowing higher power ablation and / or a smaller diameter feeder line to the antenna.

Apparatus for detecting vulnerable plaques embedded in the wall of a patient's blood vessel includes an intravascular catheter containing a microwave antenna, an extra-corporeal radiometer having a signal input, a reference input and an output, a cable for electrically connecting the antenna to the signal input, and a device for applying an indication of the patient's normal tissue temperature to the reference input so that when the catheter is moved along the vessel, the locations of the vulnerable plaques are reflected in a signal from the output as thermal anomalies due to the higher emissivity of the vulnerable plaques as compared to the normal tissue. A second embodiment of the apparatus has two coaxial antennas in the catheter serving two radiometers. One measures the temperature at locations in the vessel wall, the other measures the temperature at the surface. By subtracting the two signals, the locations of vulnerable plaque may be visualized. The apparatus employs a special diplexer for separating the signals from the two antennas and a method of detecting and possibly destroying the plaques is also disclosed.

A biopsy needle (80) having a longitudinal channel (84) formed within an inner conductor (86) of a coaxial antenna is disclosed. The coaxial antenna terminates in a rigid insertion tip (82) e.g. a ceramic cone that is insertable into biological tissue. Microwave energy (e.g. having a frequency of 1 to 100 GHz) delivered to the coaxial antenna is emitted at the insertion tip. The insertion tip may be arranged to match the impedance of the coaxial antenna to a predetermined tissue impedance. The emitted radiation can be used to measure properties of or treat (e.g. ablate) tissue at the insertion tip. Needle biopsy apparatus is also disclosed, in which a microwave energy is controllably delivered to a needle from a microwave generator. The apparatus may include an impedance tuner to dynamically match the impedance of the needle with tissue at the insertion tip.

The invention discloses a method for controlling the pointing to the ground of the coaxial antenna of a lunar satellite. The method includes the following steps: first, according to earth ephemeris information transmitted from the ground to the satellite and a transformation matrix from an equatorial inertia system to a coordinate system of a satellite orbit, the ephemeris of the earth in the coordinate system in the satellite orbit in any moment is calculated ; second, according to the calculated ephemeris, visible earth region of the satellite is calculated and within the visible region, a pointing in the coordinate system of the satellite orbit of vector about the satellite pointing to geometer is calculated; the pointing in the coordinate system of the satellite orbit of vector about the satellite pointing to geometer is calculated in a compensated way to obtain the pointing in the coordinate system of the satellite body of vector about the satellite pointing to geometer; according to the pointing in the coordinate system of the satellite body of vector about the satellite pointing to geometer, an antenna target angle is calculated; a final instruction angle is obtained after an antenna zero deviation is compensated and the final instruction angle is sent to an antenna drive mechanism which can drive the antenna to point to the earth. The invention overcomes the defects of the prior art and adopts a tracking mode of a simple ring-opening program to meet the requirements for pointing accuracy.

An antenna for microwave tumor ablation provides coaxial antenna conductors surrounded by an insulated sleeve of length and size promoting destructive interference of axial microwave energy passing inside and outside of the sleeve to limit the tail of SAR power toward the skin.

The invention discloses a trunked aircraft communication system. Each member aircraft is provided with a communication terminal which comprises a platform electronic system, a communication processing module, a control bus, an optical antenna and an omnidirectional antenna. The communication processing module has two channels which are respectively a wireless laser channel and a wireless microwave channel. As for the wireless laser channel, the optical antenna is used as a transmitting antenna. As for the wireless microwave channel, the omnidirectional antenna is used as a transmitting antenna. The wireless laser channel transmits high-speed payload data. The wireless microwave channel transmits low-speed remote control and telemetry data and platform data information. When the high-speed payload data is transmitted, position and attitude information interactions between two laser communication parts are carried out through the wireless microwave channel so as to determine the laser transmission direction and further control optical antenna pointing. And then, the high-speed payload data is transmitted through the wireless laser channel. Combining advantages of microwave communication and laser communication, heterogeneous network interconnections between member aircrafts are realized by cooperation between the two channels.

An improved antenna for microwave ablation uses a triaxial design which reduces reflected energy allowing higher power ablation and / or a smaller diameter feeder line to the antenna.

This invention belongs to a laser radar domain, which relates to a continuous wave frequency modulation cohere laser radar which is on the basis of optical fiber laser device. Optical fiber laser device is used as light source, of which launching wnd links optical fiber coupler. Optical fiber coupler divides energy of light into two parts. Moiety is used as characteristics light, which can be directly inputted in an input end of secondary optical fiber coupler, the other part is inputted in expanding bunch lens device; after expanding bunch lens compresses laser emission angle, direct surveyed area by 2-dimensional scanner; echo-signal is feed-through one end of transmission optical fiber through optical antenna by 2-dimensional scanner, the other end of transmission optical fiber contacts secondary optical fiber coupler by optical fiber amplifier. After echo-signal and characteristics light are combined and interfered to mix frequency by optical fiber coupler, enter monitor component element. Monitor component element can transform and magnify signal photoelectricity, output, post it in computer by collecting card, carry out data processing. This invention has features of small volume, light quality, high integrated degree, good stability, intelligentification and modular.

The invention relates to a data transmission system for an underwater acoustic network, which comprises a plurality of independent underwater nodes, wherein each underwater node is equivalently connected with at least the other underwater node. The data transmission system also comprises a transmitting optical antenna, a receiving optical antenna, a light source, an optical modulator, an optical receiver, an underwater acoustic transducer / receiving transducer, a digital signal processor and a positioning module, wherein the positioning module is provided with a rotating device and used for completing the alignment between the light source and the optical receiver; the transmitting optical antenna, the light source, the optical modulator and the digital signal processor are in signal connection with each other in turn; the receiving optical antenna, the optical receiver and the digital signal processor are in signal connection with each other in turn; the digital signal processor is also in signal connection with the positioning module and the underwater acoustic transducer / receiving transducer respectively; and the light source is a blue-green laser source. The invention also relates to a data transmission method for the underwater acoustic network. The invention reduces the collision probability of data in the transmission process, improves the success rate of the construction of a communication link, saves the network bandwidth, and improves the network throughout.

The invention discloses a stable phase center measurement antenna which is mainly used in the fields of geodesy and relevant subjects including marine geodesy, geophysical exploration, resource exploration, engineering surveying, engineering deformation, spacecraft docking and the like. The antenna comprises a metal base of the antenna and wave-absorbing material arranged on the upper surface of the outer edge of the metal base. The center part of the metal base is a round cavity, and a circuit board protection cover, a multi-feed slot antenna array, a supporting medium, annular wave-absorbing material in the cavity, a coaxial feed antenna and a radio frequency connector are installed in the cavity from top to bottom. Two round groove choking coils are contained between the round cavity and the outer edge of the base. The multi-feed point, wave-absorbing material and coking coil technologies are comprehensively adopted for the stable phase center measurement antenna, and thus the stable phase center measurement antenna has the advantages of being low in wide angle polarization axis ratio and high in phase center stability and can be used for various kinds of precision measurement for satellite navigation.

A microwave charged particle source is provided according to various embodiments of the invention. The microwave charged particle source can include a coaxial antenna for generating microwaves and a dielectric layer surrounding the antenna. The microwave charged particle source can also include a first gas line outside the dielectric layer for providing sputtering gases and / or a second gas line for providing cooling gas in a space between the antenna and dielectric layer. The microwave charged particle source can further include a containment shield partially surrounding the dielectric layer and an extraction grid disposed on or near an aperture in the containment shield. In use, charged particles can be formed with the generated microwaves from sputtering gases. And the charged particles can be accelerated under an electric field created from a voltage applied to the extraction grid. A method for providing microwave charged particle source is also provided.

A biconical antenna according to the present invention includes a columnar dielectric member having frustum-shaped cavities extending respectively from an upper surface and a lower surface toward a center of the columnar dielectric member, wherein flat surfaces of apex portions of the frustum-shaped cavities are parallel and in opposition to one another; a frustum-shaped feeder portion made of a conductive film provided on an inner surface of the upper cavity; and a frustum-shaped ground portion made of a conductive film provided on an inner surface of the lower cavity. The present invention realizes a more compact biconical antenna by filling the dielectric member between the feeder portion and the ground portion of the biconical antenna.

There is provided an inductively coupled plasma processing apparatus capable of reducing a RF power loss within a high frequency power supply unit (particularly, a matching unit) and capable of enhancing a plasma generation efficiency. In this inductively coupled plasma processing apparatus, a multiple number of closed-loop secondary circuits 96, 98 independent from each other are formed between a coaxial antenna group 54 and a transformer 68. Further, by varying electrostatic capacitances of variable capacitors 64 and 66, secondary currents I2A and I2B flowing through an inner antenna 58 and an outer antenna 60, respectively, of the coaxial antenna group 54 are independently controlled. Accordingly, it is possible to readily control a plasma density distribution on a semiconductor wafer W in a diametrical direction.

A coaxial antenna is implemented that combines a VHF and UHF antenna on a common radiating element. The antenna may further include a satellite antenna that, together with the VHF / UHF antenna fits into a whip antenna footprint.

The invention provides an optical antenna for multipoint laser communication and belongs to the technical field of a space laser communication. The optical antenna for multipoint laser communication provided by the invention comprises a multi-reflector splicing optical antenna with an APT (Automatically Programmed Tool) control system and a cassette beam contraction system. The optical antenna provided by the invention is constructed by improving the surface structure of a rotating paraboloid, and the laser communication of one point to multiple points at the whole periphery of the horizontal direction and in the design field angle of the pitching direction can be realized. Because the reflection is carried out by adopting laser beams received by a large-area plane reflector which is formed after multiple small-area plane reflectors are deflected, the optical antenna provided by the invention has higher energy utilization rate compared with the optical antenna with a continuous paraboloid; and simultaneously, the cassette beam contraction system is adopted to compress the diameter of the light beams which are received by a large-caliber optical antenna, thereby reducing the caliber of a subsequent system, reducing the manufacturing design difficulty and being beneficial to the miniaturization of an optical system.

The invention discloses an optical transmitting antenna system and a beam control method thereof. An optical antenna has an array structure which is formed by uniformly arranging a plurality of laser transmitting antennae and a plurality of receiving antennae. The array structure is arranged on a cambered surface (a hemispherical surface or a spherical surface). Each laser transmitting antenna comprises a transmitting multimode fiber and a transmitting micro-lens. Each receiving antenna comprises a receiving multimode fiber and a receiving micro-lens. A transmitting micro-lens is positioned in the center of each receiving micro-lens. By the optical transmitting antenna system and the beam control method thereof, the mobile communication of a near-earth atmospheric laser system is well realized, dependence on a complex acquisition pointing and tracking (APT) system is reduced, and communication reliability is improved.

The invention relates to a structured light projection diffractive optical device based on a superstructure surface, and belongs to the technical field of depth perception and optical imaging. The device provided by the invention consists of a substrate and a plurality of sub-wavelength optical antenna arrays arranged in a periodic form on the surface of the substrate, wherein the sub-wavelength optical antenna arrays are one-dimensional arrays or two-dimensional arrays; when the sub-wavelength optical antenna arrays are one-dimensional arrays, the respective optical antennas are wire grids arranged in the direction of a column and having rectangular or trapezoidal cross sections; when the sub-wavelength optical antenna arrays are two-dimensional arrays, the respective optical antennas arecylinders forming planes in the direction of a column and a row and having circular or arbitrary regular polygon shaped cross sections; in each of the sub-wavelength optical antenna arrays, the diameter of each optical antenna is 1 / 20 to 1 / 2 of the operating wavelength, the heights of the respective optical antennas are all equal and in the sub-wavelength range, and the center distances of the adjacent two optical antennas are both equal and not more than half of the operating wavelength. The device provided by the invention can realize structured light projection having a large diffraction angle, high diffraction efficiency, high uniformity and insensitive incident light polarization.

There is provided an inductively coupled plasma processing apparatus capable of reducing a RF power loss within a high frequency power supply unit (particularly, a matching unit) and capable of enhancing a plasma generation efficiency. In this inductively coupled plasma processing apparatus, a multiple number of closed-loop secondary circuits 96, 98 independent from each other are formed between a coaxial antenna group 54 and a transformer 68. Further, by varying electrostatic capacitances of variable capacitors 64 and 66, secondary currents I2A and I2B flowing through an inner antenna 58 and an outer antenna 60, respectively, of the coaxial antenna group 54 are independently controlled. Accordingly, it is possible to readily control a plasma density distribution on a semiconductor wafer W in a diametrical direction.

The invention provides a microwave reaction device using a coaxial leaky antenna and application of the microwave reaction device using the coaxial leaky antenna. The device comprises a microwave heating device and a reactor, wherein the microwave heating device comprises a microwave generation and transmission device and the coaxial leaky antenna; the microwave generation and transmission device comprises a microwave power source, an annular device, a false load, a microwave power detection device, a coaxial converter and a microwave tuning device; the coaxial leaky antenna is connected to the coaxial converter, and extends into from any end of the reactor, so that microwaves are fed back into the reactor. The device provided by the invention is high in microwave energy coaxial conversion efficiency, is uniform in microwave distribution in the reactor, can be applied to any reaction for heating by utilizing the microwaves, and is especially suitable for large-scale microwave reaction.

An antenna may include a ground plane and a solar cell spaced above the ground plane. The solar cell may have first and second power output terminals. The antenna may include a coaxial antenna feed line including an inner conductor coupled to the first power output terminal, and an outer conductor coupled to the ground plane so that the solar cell also serves as a patch antenna element. The antenna may further include a drive shunt conductor extending between the first terminal and the ground plane.

The invention discloses a spectral analysis chip and a preparation method thereof. The spectral analysis chip comprises a silicon substrate layer, a quantum dot photosensitive film, and an optical antenna from down to up, wherein the optical antenna is an array obtained by periodically arranging a metal nano structure, and the spectral analysis chip also comprises at least a pair of photoelectricdetectors formed by metal electrodes contacted with the quantum dot photosensitive film. The preparation method of the detection chip comprises the following steps: preparing optical antenna; preparing the quantum dot photosensitive film; and producing the electrodes for chip preparation. The method uses cooperated cooperation between the metal nano structure and the quantum dot photosensitive film, and uses the filtering of the optical antenna, the light field enhancement function and the quantum confinement effect of the quantum dot, wavelength modulation and sensitization can be carried outon photoelectric response of the quantum dot photosensitive film, a tunable photoelectric detector unit with high sensitivity and narrow passband can be realized, and the high-sensitivity spectral analysis chip is subjected to integrated preparation.

A biconical antenna driven by an equal-delay transformer is provided herein with a bifurcating ground plane. According to one embodiment, the biconical antenna comprises a pair of cone-shaped elements and a conducting ground plate. The cone-shaped elements are arranged back-to-back to one another and aligned along a first axis. The conducting ground plate is arranged between the cone-shaped elements in a plane perpendicular to the first axis. As described herein, the bifurcating ground plane provides the decoupling needed to eliminate the anomalous undulations, which tend to occur in the antenna response at odd-integer average quarter-wave frequencies.

The invention provides a universal synthetic aperture laser imaging radar optical antenna for transmitting and receiving a distant-field or near-field optical signal for the same synthetic aperture laser imaging radar system. The antenna transmits and receives a primary telescope by a bidirectional loop, wherein the bidirectional loop consists of a transmitting channel of an adjustable secondary telescope structure and a receiving channel of an erecting telescope structure, and is connected with a laser light source, a photoelectric detector and the primary telescope; the position of a primary mirror of the secondary telescope in the transmitting channel can be moved; erecting system defocusing is arranged in the receiving channel; and a variable aperture light diaphragm is arranged in front of the photoelectric detector. The universal synthetic aperture laser imaging radar optical antenna can realize a laser transmitting wave surface with different curvature radiuses additively offset through special quadratic phase by controlling the moving distance of transmitting the secondary telescope, and can realize adjustment of receiving directivity of the optical antenna by controlling defocusing amount of the receiving channel and size of the aperture light diaphragm while eliminating target echo received wave surface aberration.