53 results about "Antiresonance" patented technology

Anti-resonance element preform for producing an anti-resonant hollow-core fiber includes a first longitudinal axis, an ARE outer element designed in a circular arc-like manner, and an ARE inner element. The ARE outer element and the ARE inner element are connected to one another along two connecting lines, which are arranged essentially in parallel to the first longitudinal axis. The ARE outer element has an inner space, which is at least partially limited by an ARE outer wall and into which the ARE inner element, designed in a circular arc-like manner, protrudes at least partially.

The invention relates to a design method of a double-end-pair resonance type surface acoustic wave filter, which comprises the following steps of: determining a core structure component of the double-end-pair resonance type surface acoustic wave filter, comprising a piezoelectric substrate, an input transducer, an output transducer and a reflecting grating; a two-dimensional model of a pair of interdigital transducers is established by using COMSOL software based on the wavelength of the interdigital transducers, the resonant frequency and the anti-resonant frequency are simulated by changing the thickness of the interdigital transducers, the appropriate film thickness of the interdigital transducers is selected, the simulation propagation velocity of the interdigital transducers is obtained according to the resonant frequency and the anti-resonant frequency corresponding to the thickness, and the simulation propagation velocity of the interdigital transducers is calculated. Extracting equivalent circuit model parameters of the double-end pair resonant surface acoustic wave filter, performing ADS software simulation, determining the number of reflecting grating fingers, performing experimental verification, obtaining an actual center frequency and an actual propagation speed, comparing the actual center frequency with a target center frequency, if the actual center frequency is not matched with the target center frequency, repeating the operation, and if the actual center frequency is not matched with the target center frequency, repeating the operation. And the actual center frequency coincides with the target center frequency.

The invention relates to a transverse excitation bulk acoustic wave resonator with an embedded electrode structure, which belongs to the technical field of radio frequency communication and comprises a substrate, a temperature compensation layer and a piezoelectric layer which are arranged in at least one of the following layouts: (1) the temperature compensation layer and the piezoelectric layer are sequentially formed on the substrate; a groove array is etched on one side, deviating from the temperature compensation layer, of the piezoelectric layer; (2) the piezoelectric layer and the temperature compensation layer are sequentially formed on the substrate, and a groove array is etched on one side, close to the temperature compensation layer, of the piezoelectric layer and on the temperature compensation layer; the transverse excitation bulk acoustic wave resonator further comprises an embedded electrode structure and a cavity, and the embedded electrode structure is formed in the groove array so as to suppress a stray mode; the cavity is formed in the substrate. Compared with the prior art, the resonator provided by the invention can effectively suppress a stray mode, so that an admittance curve between a resonant frequency (fr) and an anti-resonant frequency (fa) is smoother.

A method for producing an anti-resonant hollow-core fiber having an outer diameter of less than 500 mm, having the steps of: providing a sheath tube, which comprises a sheath tube inner bore and a sheath tube longitudinal axis along which a sheath tube wall extends, the sheath tube wall being delimited by a sheath tube inner face and a sheath tube outer face; preparing a number of anti-resonance units, each comprising an ARU outer tube; inserting at least parts of the anti-resonance units into the sheath tube inner bore; and creating a hollow-core assembly comprising the sheath tube and the anti-resonance units by at least partially connecting the anti-resonance units to the sheath tube inner face; preparing a jacket tube, which comprises a jacket tube inner bore and a jacket tube longitudinal axis along which a jacket tube wall extends.

The application provides a film bulk acoustic resonator, comprising a substrate, an acoustic reflection structure arranged on one side of the substrate, a bottom electrode arranged on one side of the acoustic reflection structure, a piezoelectric film covering the bottom electrode, and a top electrode arranged on the side of the piezoelectric film away from the bottom electrode, wherein the side of the top electrode away from the piezoelectric film is provided with an interdigital protruding frame, the interdigital protruding frame comprises oppositely arranged first and second protruding frames, at least one pair of interdigital structures are formed by extending the first and second protruding frames towards each other and being spaced apart by a preset distance and being overlapped, and each interdigital structure comprises two interdigital structures spaced apart by a preset distance along the overlapping direction. The application can reflect two or more transverse Rayleigh-Lamb waves to achieve high reflection efficiency and improve the Q value corresponding to the anti-resonance frequency of the resonator. The peeling residue problem caused by the closed loop of the existing protruding frame can be improved.

The embodiment of the invention discloses a surface acoustic wave resonator, a surface acoustic wave filter and a multiplexer. The surface acoustic wave resonator includes: a piezoelectric layer; a conductive layer; the conductive layer comprises a first conductive unit and a second conductive unit; the first conductive unit comprises an interdigital transducer electrode, and a first bus bar and a second bus bar which are arranged at two ends of the interdigital transducer electrode; the interdigital transducer electrode comprises a plurality of first long electrode fingers and a plurality of second long electrode fingers which are alternately arranged in the first direction and extend in the second direction. Wherein in the second direction, at least one pair of adjacent first long electrode fingers are in short circuit on the side away from the first bus bar, and the second long electrode finger located between the two short-circuit first long electrode fingers is arranged in a suspended mode to form a suspended finger. The second conductive unit comprises a first reflecting grating and a second reflecting grating. According to the technical scheme, the distance between the resonance point and the anti-resonance point of the resonance unit can be shortened. The surface acoustic wave resonator is applied to a surface acoustic wave filter and can improve pass band edge roll-off.

The objective of the present invention is to provide, in order to solve the described problems, a surface acoustic wave (SAW) resonator capable of adjusting singular points through a phase change of a surface acoustic wave, and a manufacturing method therefor, the SAW resonator changing the phase of a SAW generated and propagated in an IDT electrode unit of the SAW resonator, so as to intentionally adjust singular points, that is, a resonance frequency and an anti-resonance frequency according to desired design specifications, even if a capacitor is not additionally connected to the SAW resonator while an area of the SAW resonator is maintained as is, thereby enabling skirt characteristics of a SAW pass filter including the SAW resonator to be more sharply improved according to the design specifications.

Acoustic wave filters operating at wider passband with enhanced frequency response are provided herein. In certain embodiments, an acoustic wave filter comprises an input port and an output port, a plurality of series resonators electrically connected in series between the input port and the output port, the plurality of series resonators including a first group of resonators and a second group of resonators, each resonator of the first group of resonators having a raised frame region, the second group of resonators including at least one resonator having its resonance frequency closest to one edge of a target passband that is closer to its anti-resonance frequency lacking any raised frame region such as to broaden a bandwidth of the target passband, and a plurality of shunt resonators each being electrically connected between respective series resonators and a ground.

The application discloses a kind of based on low-loss anti-resonance hollow waveguide broadband high-efficiency leaky-wave antenna design method and structure, its technical scheme includes: first based on anti-resonance principle design single dielectric wall hollow waveguide;Further introduce second dielectric wall optimization form double dielectric wall anti-resonance hollow waveguide, significantly enhance the transverse restraint to electromagnetic energy in air cavity by cascading reflection effect, realize super low loss transmission;Finally, etching periodic radiation slot in the upper layer metal plate of double dielectric wall hollow waveguide, construct leaky-wave antenna with frequency scanning function.The application uses air as main transmission medium, fundamentally reduces dielectric loss, so that the antenna has ultra-low transmission loss and ultra-high radiation efficiency in wide frequency band, while the structure is simple, process compatibility is strong, only through standard PCB process can be realized, can be widely used in 5G / 6G communication, millimeter wave radar, terahertz imaging and other high-performance wireless systems.

The invention discloses a hollow anti-resonance optical fiber with a large mode field area and ultralow loss in a middle infrared band. The cross section structure is composed of a central pentagonal hollow core area, a peripheral glass sheet connected coaxial semicircular nested pipe cladding and an outer cladding sleeve. The hollow core is an air channel with a pentagonal outline and is used for realizing the propagation of light in a low-loss medium; the cladding is composed of five symmetrically-distributed coaxial semicircular nested tube units, each unit comprises an inner semicircular arc glass sleeve and an outer semicircular arc glass sleeve which are connected by glass sheets to form a connected structure, and an anti-resonance boundary with a periodic microstructure is formed. According to the structure, the size of an air hole, the thickness of a glass wall, the radius ratio of two layers of semi-circular arcs and geometric symmetry are accurately regulated and controlled, and light of a specific wave band is limited in the hollow core through the anti-resonance effect. The invention realizes ultralow transmission loss, large mode field area and high nonlinear threshold, and is suitable for the application fields of mid-infrared laser transmission, gas sensing, spectral analysis and the like.

An acoustic wave filter package with a surface acoustic wave resonator having a capacitor coupled in parallel with the surface acoustic wave resonator. The capacitor results in a shifted anti-resonant frequency.

An anti-resonant hollow core optical assembly has a central longitudinal axis extending from a first end to a second end and a diagnostic ring structure through which the central longitudinal axis extends. The diagnostic ring structure extends longitudinally from the first end to the second end, disposed azimuthally around the central longitudinal axis, comprises an outer surface at an outer radius from the central longitudinal axis and an inner surface at an inner radius from the central longitudinal axis, and has a first refractive index. A plurality of anti-resonant elements is in contact with the inner surface. The anti-resonant elements extend longitudinally from the first end to the second end and surrounds the central longitudinal axis to define an effective core region. An outer cladding surrounds the diagnostic ring structure and has a second refractive index less than the first refractive index.

Systems for gradient surface electromagnetic wave generation and related methods are described. In some implementations, a first horn antenna may be configured to disrupt momentum conservation parallel to an interface between water and another material, enabling the generation of gradient surface electromagnetic waves. A second horn antenna, positioned in proximity to the first, may be adapted to generate anti-resonances in response to the gradient surface electromagnetic waves initiated by the first horn antenna. The presence of an object, which may be composed of metal or dielectric materials, near the interface may alter the anti-resonances generated by the horn antennas. This alteration in anti-resonances may indicate the presence of the object, thereby facilitating the detection of metallic and dielectric objects in close proximity to the water surface. This system and method may enhance biosensing and bioimaging applications by supplementing traditional x-ray and ultrasound techniques with gradient surface electromagnetic wave-based detection.

A filter device capable of realizing an increase in the amount of attenuation outside a passband. A filter device (1) has a filter circuit (3) with a plurality of series arm resonators (S1-S4) connected between a first terminal (2a) and a second terminal (2b), the series arm resonators (S1-S4) having at least two series arm resonators (S1, S3) with different anti-resonance frequencies from each other, and an additional circuit (4) connected in parallel with the filter circuit (3) between the first terminal (2a) and the second terminal (2b), the additional circuit (4) having at least three IDT electrodes (5-8) arranged along an elastic wave propagation direction, the at least three IDT electrodes (5-8) having an IDT electrode (7) connected to the filter circuit (3) on the first terminal (2a) side and IDT electrodes (5, 6, 8) connected to the filter circuit (3) on the second terminal (2b) side, the IDT electrode (7) being connected to a first node (N1) which is one end of the series arm resonator (S3) having the lowest anti-resonance frequency, the IDT electrode (5) being connected to a second node (N2) which is one end of the series arm resonators (S1, S2) other than the series arm resonator (S3) and different from the first node (N1), and the IDT electrode (8) being connected to a third node.

This invention discloses a method and apparatus for measuring the viscoelastic mechanical properties of polymers under high and low temperature environments, belonging to the field of mechanical property testing. This invention collects the admittance curves of the nth-order vibration of a resonant unit consisting of a spacer bar and a test sample, obtains the resonant frequency and anti-resonant frequency of the nth-order vibration, constructs the vibration characteristic equation and loss factor solution equation, and solves the equations to obtain the mechanical property parameters. This invention can accurately measure the viscoelastic mechanical properties of polymer materials at different temperatures. The apparatus of this invention is simple to manufacture, provides reliable measurement results, and is fast. Compared with the most commonly used methods for measuring the viscoelastic mechanical properties of polymers, whose measurement frequency range is usually below tens of Hz, this invention can obtain results at frequencies from several kHz to tens of kHz. This invention is of great significance for characterizing the mid-frequency viscoelastic mechanical properties of polymer materials and has broad application prospects.

An acoustic wave device includes series resonators and parallel resonators formed on a main surface of a piezoelectric layer. The series resonators includes a first series resonator including first, second and third series-divided resonators and a second series resonator including fourth, fifth and sixth series-divided resonators. One of the first, second and third series-divided resonators which is disposed at a position where an electric signal is input first, has a first anti-resonance frequency. The others of the first, second and third series-divided resonators have a second anti-resonance frequency. One of the fourth, fifth and sixth series-divided resonators which is centrally disposed has the second anti-resonance frequency, the others of the fourth, fifth, and sixth series-divided resonators have the first anti-resonance frequency.

To set specifications while suppressing antiresonance in a vibration control device having a plurality of tuned mass dampers.SOLUTION: A step of assuming that the plurality of tuned mass dampers 14 are sequentially installed on the structural member 52, setting a natural frequency of the tuned mass damper 14 assumed to be installed first to a primary natural frequency of the structural member 52, and then obtaining a frequency of anti-resonance generated by one or the plurality of tuned mass dampers 14 assumed to be installed first; And a process of correcting the natural frequency of one or a plurality of tuned mass dampers 14 assumed to be previously installed to the frequency of the antiresonance obtained in the process, and setting the natural frequency of the tuned mass damper 14 assumed to be installed next.SELECTED DRAWING: Figure 6

The invention relates to a lead-free transduction element for an ultrasonic transducer and a preparation method of the lead-free transduction element, and belongs to the technical field of ultrasonic transducer equipment, the lead-free transduction element is characterized in that the lead-free transduction element is composed of a lead-free piezoelectric material and a non-piezoelectric phase material, the lead-free piezoelectric material is a quadrangular prism which is uniformly cut into a latticed crystal column array, and the non-piezoelectric phase material is a non-piezoelectric phase material. The non-piezoelectric phase material is filled among the latticed crystal column arrays; the height of the composite material composed of the lead-free piezoelectric material and the non-piezoelectric phase material is 40-60 microns, and the volume of the lead-free piezoelectric material accounts for 50-60% of that of the composite material; the volume of the non-piezoelectric phase material accounts for 40%-50% of the volume of the composite material, the side length of a crystal column is 30-40 microns, the resonant frequency and the anti-resonant frequency of the composite material are both larger than 20 MHz, and the electromechanical coupling coefficient is larger than 70%. According to the invention, the harm of a lead-based piezoelectric material in an existing ultrasonic transducer transduction element to the environment and a human body is overcome, and the provided preparation method overcomes the problems that a lead-free piezoelectric single crystal is fragile and easy to crack, and a small-size crystal column is easy to collapse when being cut.

The present invention supports the implementation of structures for bulk acoustic wave resonators that can increase piezoelectric coupling and suppress parasitic modes. The grooves between the electrodes of the disclosed digital to analog converter (IDT) reduce the generation of parasitic modes and prevent the propagation of the parasitic modes and the resonance accumulation of the amplitude of the parasitic modes. In addition, the grooves between the disclosed IDT electrodes suppress a high order mode in a horizontal direction and increase the resonant-anti-resonant frequency gap of the bulk acoustic wave resonator.

A bandpass filter is provided, comprising a series resonator circuit disposed between an input and an output of the bandpass filter; a first shunt resonator circuit connected to ground in parallel with the series resonator circuit; and a second shunt resonator circuit connected to ground in parallel with the series resonator circuit, the second shunt resonator circuit configured to have one or more frequency pairs comprising an antiresonant frequency and a first resonant frequency, wherein for each frequency pair the antiresonant frequency is within a passband of the bandpass filter and the first resonant frequency at a higher frequency than the antiresonant frequency. A radiofrequency module and a wireless device comprising the same are also provided.

The invention discloses a surface acoustic wave resonator, a filter, a communication chip and electronic equipment, and aims to solve the problem of poor communication performance. In a transducer of the surface acoustic wave resonator, a first false finger is arranged on one side, deviating from a second bus bar, of a first bus bar, and the first false finger is connected with the first bus bar. The first false finger can increase the density of the side, deviating from the second bus bar, of the first bus bar, so that formation of sound waves of anti-resonance points with the frequency higher than that of the first resonance is prevented, clutters formed by coupling of the sound waves and sound waves corresponding to the second resonance are reduced, and the communication performance is improved. Besides, sound waves of the anti-resonance point with the frequency higher than that of the first resonance and sound waves corresponding to the second resonance can be scattered on the piezoelectric material layer near the first false finger, so that coupling of the sound waves of the anti-resonance point with the frequency higher than that of the first resonance and the sound waves corresponding to the second resonance is prevented, clutters are further reduced, and the communication performance is further improved.

The present application provides a filter device capable of suppressing 3rd order distortion due to an interference wave. The filter device (1) has a first filter (2A) having a first passband, which is commonly connected to a common terminal (3), and a second filter (2B) having a second passband located on a higher frequency side than the first passband. In the first filter (2A), a plurality of parallel arm resonators constitute a parallel connection portion (5) in which the plurality of parallel arm resonators are connected in parallel to each other without passing through series arm resonators. The plurality of parallel arm resonators in the parallel connection portion (5) include first and second parallel arm resonators whose anti-resonance frequencies are different from each other. When the first passband is set to f 1min ~ f 1max , the second passband is set to f 2min ~ f 2max , in the combined impedance frequency characteristic of the plurality of parallel arm resonators in the parallel connection portion, at least one of the anti-resonance frequencies other than the highest anti-resonance frequency is 2f 1min ~ f 2min , and 2f 1max ~ f 2max .

To provide a resonance frequency tracking circuit and a resonance frequency tracking method of a vibrator capable of stably tracking a resonance frequency by automatically correcting a damping capacity.SOLUTION: A resonance frequency tracking circuit of a vibrator includes a capacitance correction circuit of a damping capacitor (C0), and the capacitance correction circuit is configured to connect a voltage signal (Vf) of the vibrator to an input of a differentiation circuit, connect an output of the differentiation circuit to an input of a variable gain circuit, and subtract an output of the variable gain circuit from a current signal (If), and controls a correction amount of the damping capacitor (C0) by controlling a gain of the variable gain circuit to bring a selected anti-resonance frequency or the like (fa ") close to a target frequency (fCAL) and reduce an influence of the damping capacitor (C0).SELECTED DRAWING: Figure 5

To provide a band attenuation filter advantageous to simplification.SOLUTION: The band attenuation filter includes a signal path that passes a signal in a pass band between a first attenuation band and a second attenuation band that do not overlap with each other. The band attenuation filter includes the first and second acoustic wave resonators and / or the fifth and sixth acoustic wave resonators corresponding to the two band attenuation filters. The first and second acoustic wave resonators connect the signal path and the reference potential portion in parallel with each other and have resonant frequencies in attenuation bands different from each other. The fifth and sixth acoustic wave resonators are connected in series with each other on a skip path that bypasses a node connected to the reference potential portion of the signal path, and have anti-resonant frequencies in attenuation bands different from each other.SELECTED DRAWING: Figure 1

The present application relates to a kind of machine tool flexible ball screw system decoupling control method, first to the speed inner ring transfer function is decoupled, obtain the flexible modal item in system;Based on flexible modal item design shaping controller, the parameter of shaping controller is only determined by the anti-resonance frequency of system and anti-resonance damping ratio;Speed inner ring closed loop dynamic shaping is target second-order system, so that resonance suppression and bandwidth adjustment are realized independently by PI controller.In this way, the transfer function of position outer ring is decoupled, separates out the first order component of high-order flexible mode, and designs additional controller based on position difference feedback, the feedback gain is equal to the proportional gain size of P controller in position outer ring, and the sign is opposite, suppress the influence of the first order component of high-order flexible mode.The present application realizes the decoupling of shaping controller and P-PI controller parameter setting, simplifies parameter setting process, and improves the closed-loop bandwidth and industrial practicability of flexible ball screw feeding system.

The application discloses a transformer winding short-circuit state detection method based on pulse frequency response curve characteristics, first extracts the anti-resonance point of the amplitude-frequency response curve and the L-C zero-crossing point of the phase-frequency response curve to carry out function fitting, calculates amplitude-phase coexistence fitness TS, judges whether the winding to be detected is faulty or not; then carries out gray scale transformation on the pulse frequency response curve image, calculates image metric relationship TC, distinguishes winding inter-turn short circuit or winding capacitor fault; after judging the winding capacitor fault, calculates the gray scale-gradient coexistence rate TM of the pulse frequency response curve image, and distinguishes winding inter-turn short circuit or pie inter-turn short circuit.

The invention provides a multi-layer SAW device capable of suppressing spurious response, and aims to solve the problems that the quality factor and electromechanical coupling coefficient of the device are reduced and in-band ripple and insertion loss are deteriorated due to the fact that a traditional multi-layer SAW device easily generates spurious response when the device works, a mass block layer is deposited above a part of an IDT layer of the traditional multi-layer SAW device, and the quality factor and the electromechanical coupling coefficient of the device are reduced. By changing the length and height parameters of the mass block, observing the suppression degree of the original spurious response in the admittance frequency response, selecting several parameters with better suppression effects, further comparing the electromechanical coupling coefficient with the quality factor, and finally obtaining the optimal length and height parameters of the added mass block after comprehensive comparison. While the stray response suppression effect on the original traditional multilayer SAW device is good, the electromechanical coupling coefficient and the quality factor at the resonant frequency of the SAW device are basically kept unchanged, and the quality factor at the anti-resonant frequency of the SAW device is increased.

The invention relates to a filter, a radio frequency front-end module and electronic equipment. The filter comprises at least two resonators, resonance modes of the resonators respectively comprise a main mode and an impure mode, and the absolute value of the difference of first frequencies of the main modes of the at least two resonators in the filter is greater than the sum of half of the resonance width of the impure mode of the two resonators; wherein the resonance width is the frequency difference between the anti-resonance frequency and the resonance frequency of the mixed mode, and the first frequency is the resonance frequency, or the first frequency is the anti-resonance frequency. According to the invention, by controlling the interval of the first frequencies of the main modes of the at least two resonators, the frequency interval between the impure modes is indirectly controlled, so that the phenomenon of impure mode signal superposition between the two resonators can be improved, the passband insertion loss can be reduced or the out-of-band rejection capability can be improved, and the performance of the filter can be improved.

A method for producing a preform of an anti-resonant hollow-core fiber, which has a hollow core extending along a fiber longitudinal axis, and a cladding region surrounding the hollow core and includes at least one anti-resonance element. The method includes (a) providing a cladding tube having a cladding tube inner surface and a cladding tube outer surface, at least one anti-resonance element preform being arranged at the cladding tube inner surface, (b) providing an overlay tube including an overlay tube inner surface, the overlay tube having an inner diameter larger than an outer diameter of the cladding tube, (c) arranging the cladding tube inside the overlay tube, so that the overlay tube inner surface surrounds the cladding tube outer surface, and (d) adding the overlay tube to the cladding tube, so that the overlay tube inner surface connects to the cladding tube outer surface.

The invention relates to an anti-resonance ele-ment preform for producing an anti-resonant hollow-core fiber, in an axial top view comprising a circular first cir-cle element with a first circle radius and a circular arc-shaped first circular arc element with a first circular arc radius. Furthermore, the invention relates to a method for producing an anti resonance element preform, a preform for producing an anti-resonant hollow-core fiber comprising at least one anti-resonance element preform and an anti-resonant hol-low-core fiber. According to the invention, it is provided that the first circle element and the first circular arc element are connected to one another at two contact points.