159 results about "Antiresonance" patented technology

The invention discloses a surface acoustic wave device, which comprises a substrate, a first dielectric layer, a piezoelectric layer, an interdigital transducer and a second dielectric layer, the first dielectric layer is arranged on the substrate; the piezoelectric layer is arranged on the first dielectric layer; the interdigital transducer is arranged on the surface of the piezoelectric layer, an overlapping area is formed between the two bus bars in the extending direction of the electrode fingers, a gap area is formed between the overlapping area and the bus bars, and the gap area is adjacent to the ends, close to the overlapping area, of the bus bars; the second dielectric layer is located in at least one gap region and covers the piezoelectric layer and the electrode fingers located in the gap region; wherein the propagation speed of the sound waves in the first dielectric layer and the propagation speed of the sound waves in the second dielectric layer are larger than the propagation speed of the sound waves in the piezoelectric layer, and the thickness of the first dielectric layer and the thickness of the second dielectric layer meet the condition that h2 is smaller than or equal to 0.3 h1. The surface acoustic wave device solves the problem that the Q value of the surface acoustic wave device cannot be improved and the high-frequency impure-mode suppression effect near the anti-resonance point cannot be improved in the prior art.

The invention discloses an intelligent control method and system for a motor driver, and the method comprises the steps: building an acoustoelectric incidence matrix through collecting harmonic current and sound pressure fluctuation data in the operation process of a motor, and forming a fault feature library; identifying an available fault mode to determine an energy collection point, and performing phase deviation processing on the collection point to generate an auxiliary driving signal; performing spectrum analysis on the sound pressure fluctuation data to obtain an acoustic characteristic spectrum, extracting an efficiency indication tone through characteristic decomposition, mapping the efficiency indication tone into a torque optimization parameter, and establishing a noise reduction control table; performing spectrum analysis on the enhanced control domain to identify a high-energy frequency band, executing a frequency shift operation to generate a safety frequency band signal, and forming a multi-frequency band management strategy in combination with a noise reduction control table; a management strategy is decomposed into parallel control flows for sequential staggered arrangement, and an energy-saving control matrix is generated; and generating a PWM control signal based on the matrix, carrying out edge reconstruction, and obtaining a softened edge waveform through an anti-resonance injection technology to complete intelligent control of the motor driver.

A filter device includes a filter circuit including first and second terminals and series arm resonators along a series arm connecting the first terminal and the second terminal, and an additional circuit connected in parallel at least some of the series arm resonators. The additional circuit includes first, second, and third interdigital transducer electrodes. The first interdigital transducer electrode is connected to a first node at one end portion of a series arm resonator having a lowest anti-resonant frequency of the series arm resonators, the second interdigital transducer electrode is connected to a second node having a potential different from a potential of the first node, the third interdigital transducer electrode is connected to a third node having a potential different from the potentials of the first and second nodes, and the first and second nodes are closer to the first terminal than the third node.

A multiplexer includes first and second filters respectively with a first pass band and a second pass band on a higher frequency side than the first pass band. The first filter includes series-arm resonators and parallel-arm resonators, a resonance band width of at least one of the series-arm resonators is wider than the first pass band, one of the series-arm resonators is coupled closest to a common terminal among the series-arm resonators and the parallel-arm resonators. An anti-resonant frequency of the one of the series-arm resonators is lower than a high frequency end of the second pass band and is lowest among anti-resonant frequencies of the series-arm resonators.

Disclosed is a surface acoustic wave filter for suppressing a spurious component caused by a lateral mode, which suppresses a spurious component caused by an unnecessary lateral mode in a frequency band higher than an anti-resonant frequency or resonant frequency by having a higher sound velocity at a dummy electrode than at an interdigital transducer (IDT) electrode. The device comprises a substrate, and a supporting substrate, an energy limiting layer and a piezoelectric layer are stacked on the substrate in sequence. The first bus bar and the second bus bar extend in a first direction on the substrate and are separated from each other in a second direction perpendicular to the first direction; a plurality of first and second IDT electrodes alternately extending from the first and second bus bars in the second direction and spaced apart from each other in the first direction; a second dummy electrode extending from the second bus bar to face an end portion of each of the plurality of first IDT electrodes extending from the first bus bar; a first dummy electrode extends from the first bus bar to face an end of each of the plurality of second IDT electrodes extending from the second bus bar, a sound velocity at the dummy electrode being higher than a sound velocity at the plurality of IDT electrodes.

A vehicular compartment sound proofing structure includes a partition member 12 that partitions the vehicular compartment, a sound absorbing layer 14 having spaces therein, an air impermeable layer 30 made of air impermeable material, and a compressed fiber layer 32A mainly formed of a compressed mass of fibers. Connection strength between the compressed fiber layer 32A and the air impermeable layer 30 is lower than connection strength between the air impermeable layer 30 and the sound absorbing layer 14. Accordingly, antiresonance arises between resonance due to the resonance transmission and resonance by stretching of the sound absorbing layer 14 (refer to 10A). This improves insertion loss in the middle frequency band and soundproofing performance with respect to sound in the middle frequency band is improved.

The utility model discloses a surface acoustic wave device and a radio frequency front-end module. The surface acoustic wave device comprises an interdigital transducer, wherein the interdigital transducer comprises a first bus bar and a second bus bar which are oppositely arranged, an electrode finger and a plurality of gap electrodes; in the extending direction of the electrode fingers, an overlapping area is formed between the first bus bar and the second bus bar, a first area is formed between the overlapping area and the first bus bar, a second area is formed between the overlapping area and the second bus bar, and the first area and the second area are adjacent to the first bus bar and the second bus bar respectively; the plurality of gap electrodes are arranged in at least one of the first area and the second area, and the plurality of gap electrodes, the bus bars and the electrode fingers are arranged at intervals; wherein the plurality of gap electrodes form a first curve in the arrangement direction of the electrode fingers. According to the invention, the Q value near the anti-resonance point can be improved while the inhibition effect of the transverse mode is improved.

The invention relates to a single-polarization anti-resonance optical fiber, in particular to an asymmetric cladding structure single-polarization anti-resonance optical fiber working in a terahertz wave band, six longitudinal double-layer nested cladding tubes and two transverse double-layer nested cladding tubes are arranged in an optical fiber cladding, a protective tube is arranged outside the optical fiber cladding, and a perfect matching layer is arranged outside the protective tube; the six longitudinal double-layer nested cladding pipes are divided into two groups with the same number by the two transverse double-layer nested cladding pipes, and the six longitudinal double-layer nested cladding pipes and the two transverse double-layer nested cladding pipes are uniformly distributed on the circumference; the longitudinal double-layer nested cladding tube is composed of a first inner cladding tube and a first outer cladding tube, and the transverse double-layer nested cladding tube is composed of a second inner cladding tube and a second outer cladding tube. The loss of X polarization FM and the loss of Y polarization FM at 1 THz are 9.07 dB / m and 2.59 * 10 <-5 > dB / m respectively, and the PLR reaches up to 349318. The structure can effectively reduce the transmission loss and increase the polarization loss ratio, and the single polarization effect is good.

To reduce cost of an entire harmonic filter facility and downsize the harmonic filter facility.SOLUTION: A harmonic filter facility suppressing harmonic components included in AC voltage of a bus that is a harmonic suppression target has an LC series circuit composed of a first reactor element connected to the bus and a capacitor element connected to a low pressure side of the first reactor element, and a second reactor element connected to the capacitor element in parallel in the low pressure side of the first reactor element. Anti-resonance orders of the capacitor element and the second reactor element are set to a higher order than a fundamental frequency.SELECTED DRAWING: Figure 1

An elastic wave filter, an elastic wave multiplexer and a radio frequency front-end circuit. In an elastic wave filter (100), a first-type resonator (30) is arranged in series in a loop between an input terminal (10) and an output terminal (20); a first end of a second-type resonator (40) is connected in the loop between the input terminal (10) and the output terminal (20), and a second end of the second-type resonator (40) is grounded; the resonant frequency of the first-type resonator (30) and the anti-resonant frequency of the second-type resonator (40) are located within the frequency band range of a passband of the elastic wave filter (100); and the resonant frequency and the anti-resonant frequency of a third-type resonator (50) are both located outside the frequency band range of the passband of the elastic wave filter (100), and are greater than the maximum frequency value of the passband of the elastic wave filter (100).

The invention discloses a cluster admittance passivity control method based on inverter transformation, and the method comprises the steps: firstly obtaining an original anti-resonant frequency and an original sampling frequency of an inverter cluster; then, according to the original anti-resonant frequency, the original sampling frequency and the heterogeneous inverter, determining a target sampling frequency of the heterogeneous inverter; and then, according to the target sampling frequency, determining a filtering parameter of the heterogeneous inverter, and obtaining the configured heterogeneous inverter. And then, the configured heterogeneous inverters are put into an original inverter cluster, so that a target inverter cluster is constructed. The admittance phase of the target inverter cluster can be effectively controlled within a preset range. Through the mode, passive control in a broadband range is realized, dynamic harmonic resonance is effectively inhibited, and the interaction stability of the system is greatly improved. According to the embodiment of the invention, the stability and applicability of the inverter cluster can be improved while the complexity and cost of the system are reduced.

An acoustic wave filter includes a serial arm resonator disposed on a serial arm path connecting input / output terminals, and a parallel-arm resonator device connected between the serial arm path and the ground. The serial arm resonator is a first acoustic wave resonator. The parallel-arm resonator device includes a parallel arm resonator and an inductor connected in series between the serial arm path and the ground. The serial arm resonator and the parallel arm resonator are on the same piezoelectric substrate. The resonant frequency of the parallel-arm resonator device is lower than or equal to the low frequency end of the passband of the acoustic wave filter. The anti-resonant frequency of the parallel-arm resonator device is higher than or equal to the high frequency end of the passband.

The invention relates to the technical field of microelectronics, in particular to a high-order acoustic wave filter and communication equipment applying the same. The high-order acoustic wave filter provided by the invention comprises at least one series resonator and at least one parallel resonator, a resonator in the high-order acoustic wave filter comprises a supporting substrate, a bottom electrode, a piezoelectric film and a top electrode which are sequentially arranged from bottom to top. The top electrode is an interdigital electrode; the target mode of the resonator is a high-order sound wave mode generated by excitation of a longitudinal electric field; the product of the electrode finger spacing of the top interdigital electrodes of part of the resonators and the anti-resonant frequency is larger than the slow shear wave sound velocity of the supporting substrate, and the product of the electrode finger spacing of the interdigital electrodes of all the resonators and the upper cut-off frequency of the filter is smaller than the fast shear wave sound velocity of the supporting substrate. Therefore, the influence caused by the parasitic mode of the resonator can be reduced, and the passband of the filter can be ensured to be hardly influenced.

An anti-resonant hollow-core fiber includes a fiber cladding having an inner bore, a fiber longitudinal axis, and a fiber core radius R_Faser, and a number of anti-resonance units, each including an ARE element, an NE element, and a DNE element. The anti-resonance units are mutually spaced and are arranged so as to have no contact with one another at desired positions on an inner side of the inner bore. In the anti-resonance units, the ARE element has a circular cross section, the NE element is arranged in a first interior of the ARE element, and the DNE element is arranged at least partially into a second interior of the NE element.

The invention relates to an anti-resonant hollow core fiber (1000), comprising a fiber cladding (2000) which has an inner bore (2200), a fiber longitudinal axis (2300) and a fiber core radius R_Fiber (2310), a number of anti-resonance units (3000), each comprising • an ARE element (3100), • an NE element (3400), • a DNE element (3900), wherein the anti-resonance units (3000) are spaced apart from one another and arranged contact-free at desired positions on an inner side (2150) of the inner bore (2200), wherein in the anti-resonance units (3000) • the ARE element (3100) has a circular cross-section, • the NE element (3400) is arranged in a first interior space (3170) of the ARE element (3100), and • the DNE element (3900) is arranged at least partially in a second interior space (3470) of the NE element (3400). According to the invention,that in at least one anti-resonance unit (3000) • the NE element (3400) has a circular arc-like cross-section and is connected to the DNE element (3400) along two connecting seams (3700, 3700'), • the DNE element (3900) has an oval cross-section, and • in the cross-section, a sum of the distances of any point on a DNE element wall (3950) from two focal points (4000, 4000') is equal for all points to less than 15% of the sum of the distances.

The present invention enables a user to easily adjust a controller having a resonance frequency and an anti-resonance frequency as inputs in a motor control device for driving a servo motor. An adjustment assistance system (1) comprises a measurement processing unit (21), an input processing unit (22), a calculation processing unit (23), and a display processing unit (24). The measurement processing unit (21) measures the frequency characteristics of a control target (42) and outputs the frequency characteristics as first frequency characteristics. The calculation processing unit (23) calculates the frequency characteristics of the control target (42) on the basis of a plurality of characteristic values inputted to the input processing unit (22), and outputs the frequency characteristics as second frequency characteristics. The display processing unit (24) displays the first frequency characteristics and the second frequency characteristics.

The invention relates to an optronic sight having a critical mode, in particular an anti-resonance mode, comprising a variable fundamental frequency, and to a motorised vehicle comprising such a sight. This optronic sight for a motorised vehicle such as an aerial, marine or land vehicle, comprises: - a sighting module (13) capable of being moved about a first axis (X) and a second axis (Y) which is not parallel to the first axis; - means (14, 15) for moving the sighting module about the first axis and the second axis; and - a servo loop for slaving a position parameter of the sighting module to a setpoint, comprising an adaptive servo corrector (16) capable of calculating a command for a controlled device having a critical mode modifying the response of the device. The sight comprises means (23) capable of determining a fundamental frequency of the variable critical mode on the basis of an operating parameter of the controlled device, the corrector (16) being calculated from the fundamental frequency determined to compensate for the anti-resonance or resonance mode.

Provided is a multiplexer (1) in which the insertion loss in the passband of a common-connected filter is reduced, the multiplexer (1) being provided with: a filter (10) having a first passband; and a filter (20) having a second passband closer to the higher frequency side than the first passband, the filter (10) having series arm resonators (s11-s14) and parallel arm resonators (p11-p14), the resonance frequency band width of at least one of the series arm resonators (s11-s14) being larger than that of the first passband, the series arm resonator (s11) being connected closest to the common terminal (100) among the series arm resonators (s11-s14) and the parallel arm resonators (p11-p14), and the series arm resonator (s11) being connected closest to the common terminal (100) among the series arm resonators (s11-s14) and the parallel arm resonators (p11-p14). The anti-resonance frequency (fast 11) of the series arm resonator (s11) is lower than the high-frequency end of the second passband, and is the lowest among the anti-resonance frequencies (fast 11 to fast 14) of the series arm resonators (s11 to s14).

The invention relates to the technical field of communication equipment design, in particular to a design method and system for a broadband annular magnetoelectric antenna with a high electromechanical coupling coefficient. Constructing a vibration analysis model of the annular piezoelectric layer, and calculating to obtain a characteristic equation of rigidity and mass coefficients according to the vibration analysis model; solving the characteristic equation of the rigidity and the quality coefficient to obtain a resonant frequency and an anti-resonant frequency; the resonant frequency and the anti-resonant frequency are substituted into an electromechanical coupling coefficient formula, a size factor is introduced, and a correction formula is constructed; obtaining an optimized size parameter of the annular piezoelectric layer based on a correction formula; optimized size parameters of the annular piezoelectric layer can be obtained through simulation, the design efficiency and the performance stability of the antenna are further improved, and in practical application, the antenna can adapt to the requirements of different frequency bands and scenes more quickly.

The invention relates to the technical field of radio frequency, in particular to a pressure detection method and device based on a single surface acoustic wave resonator and a storage medium, and the method comprises the steps: S1, obtaining the temperature sensitivity coefficient information and strain sensitivity coefficient information of the resonant frequency and anti-resonant frequency of a piezoelectric substrate; s2, determining a target tangential range according to the temperature sensitivity coefficient information and the strain sensitivity coefficient information; s3, calculating and determining a strain-frequency incidence relation based on the target tangential range; and S4, detecting and determining pressure information according to the strain-frequency association relationship. Through the resonant frequency information and the anti-resonant frequency information of the piezoelectric substrate, pressure inspection and temperature compensation are realized, and only one resonator is needed, so that the overall size of the device is small, and the problem that the temperatures of a multi-resonator structure are different does not exist.

The present invention discloses a microstrip line tuning circuit. The tuning circuit is composed of a single-layer PCB circuit board, and the single-layer PCB circuit board consists of three parts: a front copper-clad microstrip line, a dielectric board, and a back copper-clad ground plane. The front copper-clad microstrip line includes: an input pad, an output pad, an input impedance transformation section, an output impedance transformation section, and a resonator composed of a plurality of parallel open stubs. The above resonator eliminates the impedance discontinuity phenomenon caused by electromagnetic mode conversion near the corresponding frequency point of the ultra-wideband radiation unit through "anti-resonance", so as to achieve the purpose of expanding the impedance bandwidth. Considering that the most widely used base station antenna radiation units currently basically operate below the third-order mode, the above microstrip line tuning circuit is optimized to a suitable resonance frequency, and theoretically adapts to almost all radiation units, significantly improving the impedance bandwidth. The present invention also provides a base station antenna.

The invention provides a hollow-core anti-resonance optical fiber temperature sensor based on surface plasma resonance. The hollow-core anti-resonance optical fiber temperature sensor comprises a cladding region and a fiber core region, the cladding area comprises four cylindrical nested elliptical quartz tubes and two quartz tubes which are uniformly arranged, the quartz tubes intersect with the tube wall of the optical fiber, the inner radius of each cylindrical nested elliptical quartz tube is r1, the inner minor semi-axis of each nested elliptical quartz tube is a, and the tube wall thickness of each cylindrical nested elliptical quartz tube is t1; the inner radius of the quartz tube intersected with the tube wall of the optical fiber is r2, and the thickness of the tube wall is t2; the sensor adopts an anti-resonance optical fiber structure, and a cladding area is formed by uniformly arranging four cylindrical nested elliptical quartz tubes and two quartz tubes intersected with the tube wall of the optical fiber. The two quartz tubes in the x direction are filled with gold threads, and other cladding tube holes are filled with ethanol liquid; the fiber core area is an area enclosed by the six quartz tubes and is filled with ethanol liquid. According to the invention, a surface plasma effect sensing mechanism is realized by filling metal, so that temperature sensing is realized. The detection temperature range of the sensor is-50 DEG C to 50 DEG C, and the sensitivity is 3.16 nm / DEG C. The sensor has the advantages of simple structure and high sensitivity, and has wide application prospects in the fields of biomedicine, environmental science, aerospace and the like.

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 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.

To provide a multiple resonance type LLC resonant tank which is applicable to an application of a wide control range of a voltage regulation and a large step-up / step-down ratio with less component elements and capable of sufficiently narrowing down output in the case of a lightweight load and with which sufficient output can be expected by a parameter of a high frequency transformer in the case of a heavy load.SOLUTION: A capacitor for anti-resonance is connected in parallel with a resonance inductor constituting an LLC resonant tank in which excitation inductance, a resonant inductor and a resonant capacitor are connected in series. Regarding anti-resonance, impedance becomes theoretically infinitely large in a resonant frequency, so that a voltage in an output end is zero. Therefore, a voltage conversion ratio of the LLC resonant tank becomes zero. Frequency control is performed between a normal resonant frequency (first resonant frequency) of the LLC resonant tank and a resonant frequency of newly configured anti-resonance (second resonant frequency), so that voltage regulation control can be performed over a wide range.SELECTED DRAWING: Figure 1

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.

Described herein is a method of estimating a quantity dependent on a capacitance (Cf) of an electrical filter connected to an AC side of an electrical converter. The method includes injecting a plurality of frequency components into a voltage reference of the electrical converter; operating the electrical converter with the voltage reference by determining switching commands from the voltage reference and applying the switching commands to the electrical converter; determining an AC side voltage (uc) and an AC side current (ic) in the AC side of the electrical converter and determining a filter admittance and / or filter impedance from the AC side voltage (uc) and the AC side current (ic); determining at least one of a resonance frequency and an anti-resonance frequency of the electrical filter; and determining the quantity dependent on the capacitance (Cf) of the electrical filter from the resonance frequency and / or the anti-resonance frequency.

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.