350 results about "Coaxial waveguides" patented technology

Provided are coaxial waveguide microstructures. The microstructures include a substrate and a coaxial waveguide disposed above the substrate. The coaxial waveguide includes: a center conductor; an outer conductor including one or more walls, spaced apart from and disposed around the center conductor; one or more dielectric support members for supporting the center conductor in contact with the center conductor and enclosed within the outer conductor; and a core volume between the center conductor and the outer conductor, wherein the core volume is under vacuum or in a gas state. Also provided are methods of forming coaxial waveguide microstructures by a sequential build process and hermetic packages which include a coaxial waveguide microstructure.

The invention provides a Ku/Ka frequency band circularly polarization integrated receiving and transmitting feed source antenna applied to antenna systems, such as a paraboloid antenna and the like, in satellite communication. The antenna adopts a coaxial nested compact structure, and is applied to Ku frequency band and Ka frequency band at the same time. The basic structure of a feed source comprises a circular waveguide, on which a pointed cone shaped dielectric rod is loaded, a flange, a coaxial waveguide, a symmetrical SMA connector pair, a circular polarizer and an orthogonal mode coupler, wherein the feed source in the Ka frequency band is applied to dual circular polarization, has rotary symmetrical radiation directional diagrams, the circularly polarization axial ratio in Ka double band is smaller than minus 2dB, and the transmitter-receiver isolation is smaller than minus 70dB; and the feed source in the Ku frequency band is applied to dual circular polarization, has rotary symmetrical radiation directional diagrams, a cross polarization level smaller than minus 40dB, and good transmitter-receiver isolation and reflection loss.

A multiband waveguide reflector antenna feed comprises waveguide feeds in a concentric architecture. A waveguide feed is located in the center and coaxial waveguide feeds are disposed around the center feed. The waveguide feeds may be all-metallic with the center feed operating in a TE₁₁ mode and the coaxial feeds operating in a coaxial TE₁₁ mode. The waveguide feeds may have electromagnetic band gap (EBG) surfaces on waveguide surfaces. The center waveguide feed may have an EBG outer conductor surface and operate in a circular waveguide TEM mode. The coaxial waveguide feeds may have EBG inner and outer conductors and operate in a circular waveguide TEM mode. The coaxial feeds may have EBG inner conductors and near perfect electrical conductor (PEC) outer conductors and operate in a circular waveguide-like TE₁₁ mode or may comprise EBG outer conductors and PEC inner conductors and operate in a quasi-TEM waveguide mode.

The present invention relates to a plasma processing apparatus including: a processing chamber whose ceiling portion is opened and the inside thereof can be evacuated to vacuum; a ceiling plate which is made of dielectric material and is airtightly mounted to an opening of the ceiling portion; a planar antenna member which is installed on a top surface of the ceiling plate, for introducing a microwave into the processing chamber; and a coaxial waveguide, which has a central conductor connected to the planar antenna member, for supplying the microwave, wherein a gas passage is formed to pass through the central conductor, the planar antenna member, and the ceiling plate, and an electric field attenuating recess for attenuating an electric field intensity of the center portion of the ceiling plate is installed on a top surface of a center area of the ceiling plate.

Provided is a plasma processing apparatus having a coaxial waveguide structure in which characteristic impedance of an input side and characteristic impedance of an output side are different. A microwave plasma processing apparatus, which plasma-processes a substrate by exciting a gas by using a microwave, includes: a processing container; a microwave source, which outputs a microwave, a first coaxial waveguide, which transmits the microwave output from the microwave source; and a dielectric plate, which is adjacent to the first coaxial waveguide while facing an inner side of the processing container, and emits the microwave transmitted from the first coaxial waveguide into the processing container. A thickness ratio between an inner conductor and an outer conductor of the first coaxial waveguide is not uniform along a longitudinal direction.

A microwave resonance plasma generating apparatus, a plasma processing system having the same and a method of generating a microwave resonance plasma are provided. The apparatus includes a microwave generating unit which generates a microwave, and a plasma producing unit which produces electrons and photons of high energy using the microwave generated from the microwave generating unit. The plasma producing unit includes a coaxial waveguide having an inner electrode disposed adjacent to the microwave generating unit, an outer electrode connected to the microwave generating unit and disposed to coaxially surround a portion of the inner electrode, the outer electrode being shorter than the inner electrode, and a dielectric tube disposed between the inner electrode and the outer electrode to insulate between the inner electrode and the outer electrode. The coaxial waveguide utilizes a principle of “cut or truncated electrode of coaxial waveguide” and a resonance phenomenon of Langmiur.

A compact plasma generating apparatus providing high efficiency of plasma excitation is presented. A plasma generating apparatus (100) comprises a microwave generating apparatus (10) for generating microwaves, a coaxial waveguide (20) having a coaxial structure comprising an inner tube (20a) and an outer tube (20b), a monopole antenna (21) being attached to one end of said inner tube (20a), for directing the microwaves generated by said microwave generating apparatus (10) to the monopole antenna (21), a resonator (22) composed of dielectric material for holding the monopole antenna (21), and a chamber (23) in which a specific process gas is fed for plasma excitation. The chamber (23) has an open surface and the resonator (22) is placed on this open surface, and the process gas is excited by the microwaves radiated from the monopole antenna (21) through the resonator (22) into the interior of the chamber (23) to generate plasma.

The invention relates to a microwave liquid nitrogen synergic freeze thawing coal seam anti-reflection method. According to the method, a freeze thawing drill hole is drilled in a coal seam, and two gas extraction drill holes are constructed at two sides of the freeze thawing drill hole. A microwave antenna, a coaxial waveguide, a water injection tube and a liquid nitrogen tube are sent into the freeze thawing drill hole together; firstly, a water injection pump is started, and water is injected into the freeze thawing drill hole; then a liquid nitrogen pump is started, and liquid nitrogen is injected into the freeze thawing drill hole to freeze water in the hole into ice so as to fracture the coal seam; and finally, a microwave generator is started, and produced microwave reaches the microwave antenna via a rectangular waveguide, a waveguide converter and the coaxial waveguide and is radiated to the freeze thawing drill hole by the microwave antenna, so that ice in the hole is quickly melted and gasified, high-temperature high-pressure water steam continues to fracture the coal seam, and gas is continuously desorbed at high temperature and rushes to the gas extraction drill holes along fractures in coal. According to the invention, microwave radiation is combined with liquid nitrogen freeze thawing, thus greatly improving the porosity and the permeability of the coal seam, promoting gas desorption, and further greatly improving the gas extraction efficiency and having wide practicability.

A seal integrity verification system scans for changes in impedance in a seal with integral coaxial waveguide, twisted pair wires, parallel ribbon wires or parallel wires. The wires are monitored by a TDR to note changes in impedance. The changes indicate the location where the seal is not under proper compression to ensure a tight fit. This is especially useful in verifying that watertight doors on ships or submarines are sealing properly when shut.

The invention relates to a coaxial-ridge waveguide-microstrip conversion structure ultra-broadband multi-channel power splitter. The input coaxial joint and the extended coaxial waveguide adopt a tapered coaxial gradual transition, and the tapered coaxial gradual transition And the ridge waveguide-microstrip conversion structure can realize ultra-wideband impedance matching; N ridge waveguide-microstrip conversion structures are uniformly distributed along the circumference in the extended coaxial waveguide to realize N-way parallel power division, and the entire power division circuit has axisymmetric To ensure that the signal amplitudes and phases of the N-channel power division signals are equal, the N-channel signal power division can be realized in one step, which can minimize the signal transmission loss. The present invention has ultra-wideband, low transmission loss, can realize any multi-channel power division output, each power division output signal has good amplitude and phase consistency, flat group delay characteristics in the band, and is easy to integrate with other peripheral planar circuits, etc. advantage. The invention is mainly used in microwave and millimeter wave power synthesis amplification systems, array antennas, etc., and has broad application prospects in microwave and millimeter wave systems such as communication and radar.

A mechanism for coupling a coaxial waveguide to another waveguide. The mechanism includes a lower or matching waveguide and an impedance transformer. A coaxial port couples the coaxial waveguide to the matching waveguide. The matching waveguide has a waveguide impedance which is close to the impedance of the coaxial waveguide. This arrangement allows matching between the coaxial waveguide and the matching waveguide over a wider frequency band. The impedance transformer couples the matching waveguide to the other waveguide. The impedance transformer comprises a single-stage, double-stage, or multi-stage transformer. The mechanism is suitable for coupling an antenna to a coaxial cable interface in a radar or microwave based level measurement or time of flight ranging systems.

A microwave inlet for introducing microwaves (coaxial waveguide) and a microwave launcher for generating volume-wave plasma are arranged on one side in a vacuum chamber, and a movable metal plate is arranged opposite to the microwave launcher on the other side in the vacuum chamber. The microwave launcher has a sandwiched structure where a quartz plate is sandwiched by a perforated plate having many holes of a specified diameter. Microwaves are introduced from an external microwave generator to the microwave launcher in, for example, oxygen gas, a mixture of helium gas and oxygen gas, a mixture of argon gas and oxygen gas, or a mixture of oxygen gas and nitrogen gas to change the spatial distribution of the electric field intensity, whereby the volume-wave plasma discharge is diffused to the entire inner space of the vacuum chamber by microwaves leaking through the holes in the perforated plate. The sterilizing method and the device of this invention use microwave discharge plasma that enables sterilization inside a perforated resinous package, such as a package of medical instruments in a vacuum chamber.

A multi band antenna feed, for supporting multiple frequency bands, is coupled to a reflector and includes a cylindrical core waveguide and at least three coaxial cylinders, encircling said cylindrical core waveguide and forming at least three coaxial waveguides, bounded between pairs of consecutive coaxial cylinders. The cylindrical core waveguide and the at least three coaxial waveguides provide a pair of sum and difference radiation patterns, for each frequency band: a C-band, an S-band and an L-band.

A plasma processing system 10 includes a processing chamber 100, a microwave source 700 that outputs a microwave, a coaxial waveguide 315 that transfers the microwave from the microwave source, a plurality of dielectric plates 305 that transmit the microwave transferred through the coaxial waveguide 315 and discharge the microwave into the processing chamber 100, and a metal electrode 310 having a first end and a second end, the first end coupled to the coaxial waveguide 315, the second end disposed on the surface of the dielectric plate 305 facing the substrate. The coaxial waveguide 315 holds the dielectric plate 305 and metal electrode 310 and is securely fastened by a fastening mechanism 500. The coaxial waveguide 315 is given a force by the spring member 515, the force being directed away from the processing chamber 100.