50results about How to "Adjustable resonance frequency" patented technology

An electromagnetic exciter includes a first suspension having a cylindrical side wall portion coaxial with respect to a cylindrical wall of a yoke of a magnetic circuit assembly, and a spring portion integrally formed at the lower end of the cylindrical side wall portion to support the lower end of the magnetic circuit assembly so that the magnetic circuit assembly is vibratable. An annular support member is secured to the inner peripheral surface of the upper end opening of the cylindrical side wall portion of the first suspension. A printed wiring board that supports a voice coil is supported on the annular support member. A protector has a cylindrical portion installed to cover the outer peripheral surface of the cylindrical side wall portion of the first suspension, and a caulking portion that is bent radially inward over the upper end edge of the cylindrical side wall portion of the first suspension to clamp the printed wiring board between itself and the annular support member.

The invention discloses a frequency-adjustable stretchable liquid metal antenna which comprises a stretchable base plate, wherein a curve-shaped liquid metal micro-flow way is machined on the stretchable base plate, and the liquid metal micro-flow way is internally filled with liquid metal or liquid metal alloy; when the stretchable base plate is transversely stretched, the liquid metal or the liquid metal alloy in the curve-shaped micro-flow way is lengthways and transversely deformed, and the length change of the stretched liquid metal antenna is controlled by presetting the proportional relation between the lengthways deformation and the transverse deformation, so that the work efficiency of the transversely-stretched liquid metal antenna can be adjusted. The invention further provides a manufacture method of the frequency-adjustable stretchable liquid metal antenna. According to the frequency-adjustable stretchable liquid metal antenna and the manufacture method of the liquid metal antenna, the length change of the stretched liquid metal antenna is controlled by presetting the proportional relation between the lengthways deformation and the transverse deformation, so that the work efficiency of the transversely-stretched liquid metal antenna can be adjusted.

A wireless LAN antenna/card which can transmit/receive RF signals in a high frequency band (e.g., 5 GHz) and a low frequency band (e.g., 2.4 GHz), includes a radiation electrode, a matching electrode and a feeding electrode. The radiation electrode has a predetermined area to define a transmission/reception frequency band of the antenna. The matching electrode has at least one open stub. The feeding electrode has a feeding point formed at an arbitrary position of the feeding electrode to receive a current, a first end connected to the radiation electrode, and a second end connected to the matching electrode. Further, the feeding point and a ground point are arbitrarily set on the feeding electrode, thus adjusting the impedance and frequency of the wireless LAN antenna.

The invention provides an active frequency selective surface structure based on a varactor diode, comprising a dielectric plate, and a top metal layer and a bottom metal layer respectively arranged onthe upper surface and the lower surface of the dielectric plate; the dielectric plate is provided with a metal through hole penetrating the dielectric plate and communicating with the top metal layerand the bottom metal layer; the bottom metal layer comprises a first metal sheet vertically centrally arranged, and two second metal sheets symmetrically arranged along the first metal sheet, and thesecond metal sheets are horizontally centrally distributed; the top metal layer comprises a center metal sheet and four metal sheets arranged around the center metal sheet and distributed symmetrically in the center. A metal gap is for between two adjacent metal sheets, and a varactor diode is load between that metal gaps. The structure is based on the load of a varactor diode, simple in structure, simple in feeding mode, adjustable in resonant frequency and wide in moving range, and keeps the insensitivity of resonant frequency to polarization, so the structure is suitable for complex electromagnetic environment.

A dual band antenna contains a first radiating conductor plate disposed substantially parallel to a grounding conductor, a power-supplying conductor plate extending downwards from the first radiating conductor plate, a connecting conductor plate for connecting the first radiating conductor plate to the grounding conductor, a second radiating conductor plate provided upright beneath the first radiating conductor plate and having a substantially wedge-shaped, elastically deformable portion, and a synthetic resin adjusting screw threaded to the first radiating conductor plate for depressing the top portion of the second radiating conductor plate downwards. The first and second radiating conductor plates resonate at first and second frequencies respectively (with f₂>f₁). The gap between the second radiating conductor plate and the first radiating conductor plate can be changed.

The invention belongs to the technical field of spintronics, and particularly relates to a spintronics device based on a metamaterial. The spintronics device disclosed by the invention is a composite metamaterial system formed by combining a magnetic metal material and a non-magnetic metal material; the upper layer of the spintronics device is of a metal structure consisting of two similar split-ring resonator structures back to back, metal structural units are periodically attached onto an insulating substrate, and the dimensions of the upper layer are in the sub-wavelength magnitude; and the lower layer of the spintronics device consists of periodical metal strips and strips with gradually changing widths, and a magnetic film is arranged at the narrowest place of each metal strip. The structural resonance of the non-magnetic metal material can concentrate electromagnetic waves inside the structure at maximum efficiency, namely a perfect absorption mode is realized; and moreover, the electromagnetic waves are absorbed by using a spinning rectification effect generated by electron spin motion and nonlinear coupling of charge current in a ferromagnetic material, so that a direct current voltage signal is generated. Therefore, the magnetic metal material is placed at the position with strongest electromagnetic field and current in the system, the electromagnetic waves generated by structural resonance are absorbed, and available direct current voltage is generated.

Mass portions of torsional dampers are annular surrounding corresponding elastic portions. The mass portion of the torsional damper has a first inclined face formed such that the elastic portion deforms in a sheared manner as the mass portion rotates in a rotational direction with respect to a companion flange and the elastic portion partially deforms in a compressed manner as the mass portion rotates in a direction other than the rotational direction. The mass portion of the torsional damper has second inclined faces formed such that the elastic portion deforms in a sheared manner as the mass portion rotates in the direction of the rotational axis of the companion flange and the elastic portion partially deforms in a compressed manner as the mass portion rotates in a direction other than the direction of the rotational axis.

The invention discloses a pressure sensor utilizing electrostatic negative stiffness and a production method of the pressure sensor. The pressure sensor comprises a pressure-sensitive layer, a cantilever-type resonance layer, a vacuum-sealed cover layer and electrodes from bottom to top. The production method includes taking photoresist as a mask to process an electrode hole and a lead gap on a glass sheet, and connecting the electrode hole and the lead gap with a silicon wafer to etch out a drive silicon electrode and a detect silicon electrode; reserving a mask window in a metal mask or a silicon oxide prior to etching out blind grooves both on the top and bottom surfaces of the cantilever-type resonance layer; etching out the lead gap of the cantilever-type resonance layer and a cantilever beam with a mass; taking the silicon oxide layer and a silicon nitride layer as masks to etch out a pressure-sensitive film and a grounding electrode which are single-sided to produce the pressure-sensitive layer; connecting both the upper end and the lower end of the cantilever-type resonance layer to form a combined piece prior to connecting with the vacuum-sealed cover layer to form a three-layer combined piece; mounting the three-layer combined piece to a hard board jig; producing a metal layer covering the grounding electrode and a lead electrode of the drive silicon electrode by means of spurting and evaporating so as to form the sensor finally.

The invention discloses a frequency-adjustable transverse field excitation film bulk acoustic resonator and a preparation method thereof. The frequency-adjustable transverse field excitation film bulkacoustic resonator sequentially comprises electrode aluminum, a piezoelectric substrate lithium tantalate, temperature compensation layer silicon dioxide and substrate silicon from top to bottom, wherein the substrate is provided with a cavity, the cavity is communicated with a release through hole penetrating through the temperature compensation layer and the piezoelectric substrate, and the piezoelectric substrate is made of a single crystal material. Under the condition that the thickness of the piezoelectric substrate is not changed, the center frequency of the resonator changes along with the change of the excitation direction of the electrode pair.

The invention relates to negative magnetic conductivity material, in particular to negative magnetic conductivity material which has a ring structure with appropriate thickness. Compared with the former material, the metal ring of the negative magnet conductivity material of the invention adopts the appropriate thickness, the plane in which the metal ring exists is in parallel with the direction of the magnetic field, namely vertical to the direction of the wave vector, and the material can generate magnetism resonance for realizing the negative magnetic conductivity. The adjustable microwave band negative magnetic conductivity material with minus 23.33 dB to minus 4.19 dB intensity of 900 MHz to 17500 MHz resonance frequency can be prepared through adjusting the internal and external diameters, the thickness, and the opening of the unit ring.

The invention relates to a cavity filter device and a cavity cover plate assembly thereof. A cover plate comprises a substrate, a metal layer covering the outer surface of the substrate and metal sheets formed on the inner surface of the substrate. Debugging via holes are formed in the positions, corresponding to resonant cavities and a coupling channel, of the cover plate. The cover plate of a printed board structure is adopted to replace a traditional metal cover plate, the metal layer is matched with the metal cavity to form a closed shielding space, and the metal sheets are coupled or electrically connected with the corresponding resonant columns, so that the resonant frequency is effectively reduced. Therefore, under the condition that the movable resonant column with the disc is notused, the corresponding index requirement can be met, and therefore only the metal cavity with small height is needed. By controlling the depth of a tuning rod inserted into the metal cavity, the adjustable resonant frequency and coupling amount can be realized. Moreover, the surplus part of the tuning rod is sheared, and the tail end of the tuning rod is flush with the outer surface of the coverplate. Therefore, the cavity filter device can realize miniaturization, light weight and low cost while ensuring excellent electrical indexes.

The invention discloses a separation type acoustic agglomeration suspended fine particle emission reduction system based on a resonant cavity. A closed coupling cavity (5) is coupled to a resonant agglomerating chamber (7) through a length adjustable short pipe (8), the closed coupling cavity (5) is connected with an electric-gas modulation sound generation head (3) through an index model cylinder (4), and the electric-gas modulation sound generation head (3) is connected with a signal generator and a power amplifier (20); an exhaust port (9) is formed in the closed coupling cavity (5); a bent thin-wall pipeline (6) is arranged in the resonant agglomerating chamber (7). The closed coupling cavity is coupled to the resonant agglomerating chamber through the length adjustable short pipe, and the resonance frequency of the resonant agglomerating chamber can be made to be equal to the optimal agglomerating frequency of particles in smoke by adjusting the length of the short pipe. Under the action of sound waves, relative velocity is generated through vibration of particles in smoke in the bent thin-wall pipeline, aggregates with large particle size are formed through collision and agglomeration, and the aggregates settle or are eliminated by conventional dedusting equipment. The system is small in occupied space, low in energy consumption, easy to operate, and high in expandability and dedusting efficiency.

The invention discloses a board-level integrated magnetic induction sensor based on a surface acoustic wave resonator, which comprises a high-frequency substrate (7), a surface acoustic wave resonatorchip, a planar magnetic induction coil (71) and multiple metal membrane wires, wherein the surface acoustic wave resonator chip is attached to a chip bonding area at one side of the top surface of the high-frequency substrate (7); the planar magnetic induction coil (71) is etched at the other side of the top surface of the high-frequency substrate (7); the multiple metal membrane wires are etchedon the bottom surface of the high-frequency substrate (7); and the inner end and the outer end of the planar magnetic induction coil (71) are respectively connected with a surface acoustic wave resonator voltage regulation electrode layer and a DC grounding electrode on the high-frequency substrate through the metal membrane wires, a metal through hole, a DC electrode and a bonding lead (9). According to the board-level integrated magnetic induction sensor based on the surface acoustic wave resonator, digital acquisition and processing of the magnetic induction signals can be realized conveniently, and the adjustment is flexible and convenient.

The invention relates to a broadband electrostatic micro-energy collector and collection system, and a preparation method of the collector. The broadband electrostatic micro-energy collector comprisesan upper electrode, a high-elasticity polymer film, a lower electrode and a support arranged in sequence, a mass block fixedly bonded to the middle of the upper electrode, an upper electrode lead connected with the upper electrode and a lower electrode lead connected with the lower electrode; the upper electrode is connected with the high-elasticity polymer film in an attached mode; the middle ofthe support is provided with a groove in a direction away from the high-elasticity polymer film; the two ends of the support are connected with the high-elasticity polymer film in an attached mode; the lower electrode is attached to the interior of the groove; and a cavity is formed between the lower electrode and the high-elasticity polymer film. Compared with the prior art, the collector has the advantages of being simple in structure, adjustable in resonant frequency, wide in frequency band and the like, and can be used for environmental vibration energy collection, human motion energy collection and the like.

The invention discloses a loss compensation type electrically tuned active resonator and a loss compensation method thereof. The loss compensation type electrically tuned active resonator comprises aninput port (1), a parallel resonance body (3), a compensation amplifier (5), a signal switch (4) and a variable capacitor (2); the parallel resonance body (3) and the variable capacitor (2) form a parallel LC (inductance capacitance) resonator; the compensation amplifier (5) amplifies a microwave signal from the open circuit end of the parallel resonance body (3) to form a compensation current, and then the compensation current is injected into the parallel resonance body (3) from other parts of the parallel resonance body (3), so that a signal current on the parallel resonance body (3) is enhanced and the loss in the resonator is compensated; the compensation amount of the loss of the active resonator can be changed by changing the current gain of the compensation amplifier (5), so thatthe Q value of the active resonator is adjustable; and the signal switch (4) is combined with the variable capacitor (2), so that the active resonator can be continuously tunable in a frequency band division mode. The loss compensation type electrically tuned active resonator can be realized by using an integrated circuit process of gallium arsenide, silicon and the like, and low-voltage direct-current voltage tuning is adopted; and the size is small, the resonant frequency is adjustable, the Q value (quality factor) is adjustable, and the tuning range is wide.

An antenna device for vehicle that is attached to a roof of a vehicle, the antenna device for vehicle including: an antenna base; an antenna case covering the antenna base from above; and an antenna element provided inside the antenna case, wherein the antenna base has a metal base fixed to the roof, and a metal plate electrically connected to the metal base.