99 results about "Passband" patented technology

This invention discloses an infrared narrow-band passband and wide-cutoff-band high-optical-density filter based on a CaF2 substrate. It comprises a front film system and a back film system designed on both sides of the CaF2 substrate, with each film system consisting of alternating deposits of Ge and ZnS. The front film system is: 0.762(0.5HL0.5H)^M1 + 1.246(0.5LH.5L)^M2; the back film system is: 0.56(0.5HL0.5H)^M3 + 0.39(0.5HL0.5H)^M4 + 0.28(0.5HL0.5H)^M5 + 0.2(0.5HL0.5H)^M6L. The resulting filter, when tested with a spectrometer, achieves a cutoff bandwidth of 1000nm-7100nm and 8500nm-20000nm, with an average cutoff optical density reaching OD4; the transmission band of 7669±120nm has an average transmittance of 98.85%, and a half-wavelength of 470nm±30nm.

The application provides a single-layer three-passband terahertz filter metamaterial, which comprises a metamaterial sheet layer and a plurality of artificial microstructures arranged in an array in the metamaterial sheet layer, each artificial microstructure and a corresponding part of the metamaterial sheet layer are defined as a metamaterial unit together, each metamaterial sheet layer can be regarded as being arranged by the array of the metamaterial units, when electromagnetic waves enter the metamaterial, the artificial microstructures are coupled to enable the metamaterial to reflect electromagnetic waves of other frequencies by reflecting terahertz wave bands of three specific frequency ranges, namely, the metamaterial is equivalent to a three-passband terahertz filter, and the application demand of different terahertz frequency bands can be met; in addition, compared with traditional metal-dielectric and metal-dielectric-metal filter metamaterials, the metamaterial composed of only a single metamaterial sheet layer has the advantages of light weight, low price and easy processing, the metamaterial can greatly reduce the processing difficulty of designing and processing terahertz devices, and is beneficial to the development of terahertz technology.

This invention relates to the field of optical imaging technology, specifically providing an optical radar co-aperture off-axis imaging system, comprising: an off-axis mirror assembly, a frequency-splitting device, a radar transceiver system, and an optical imaging system. The frequency-splitting device is disposed in the rear optical path of the secondary mirror and is used to reflect light waves and transmit microwaves. The frequency-splitting device includes a frequency-selective surface, which comprises an FSS pattern layer and a bias line layer. The FSS pattern layer includes periodically arranged FSS units. Nonlinear capacitors are electrically connected to the FSS units. The bias line layer applies a voltage to the nonlinear capacitors according to the received microwave band. By changing the voltage applied to the nonlinear capacitors, the resonant frequency of the FSS units is tuned, thereby changing the microwave passband frequency of the frequency-splitting device. This invention not only achieves a reflective wave-transmitting microwave design but also solves the problem that transmitting only a single band of microwaves in microwave-transmitting and light-reflecting methods is difficult to adapt to different task requirements.

The present application provides an adjustable radio frequency unit, a filter, and an electronic device. The adjustable radio frequency unit includes a first tunable dielectric layer and a second tunable dielectric layer; a first conductive layer located between the first tunable dielectric layer and the second tunable dielectric layer; a second conductive layer located on the side, away from the first conductive layer, of the first tunable dielectric layer; and a third conductive layer located on the side, away from the first conductive layer, of the second tunable dielectric layer; wherein orthographic projections of the first conductive layer, the second conductive layer and the third conductive layer on the first tunable dielectric layer at least partially overlap with one another. The adjustable radio frequency unit has the characteristic of passband adjustability and with high adjustment precision, good controllability, wide working frequency range, and low loss and cost.

This disclosure relates to the field of thermal automatic control, specifically to a speed signal processing method and system. The system includes: a speed measuring gear, a magnetoresistive speed sensor, a first capacitor, a signal shaping module, and a controller. The speed measuring gear and the magnetoresistive speed sensor are arranged adjacently and separated by an air gap threshold. The magnetoresistive speed sensor is connected to both ends of the first capacitor to generate a speed signal when the speed measuring gear rotates. The first capacitor is used to remove zero-crossing harmonics from the speed signal to correct it. The first and second input ports of the signal shaping module are connected to both ends of the first capacitor to generate a square wave signal based on the corrected speed signal. The controller receives the square wave signal. Thus, the first capacitor selects the frequency of the speed signal, removes zero-crossing harmonics outside the passband, and repairs the distorted speed waveform to obtain a sine wave.

This invention belongs to the field of electromagnetic protection technology and provides a low-profile energy selective surface with ultra-wideband protection to solve electromagnetic protection problems. This invention improves the equivalent circuit design of a cascaded energy selective surface and a frequency selective surface, resulting in a low-profile energy selective surface with ultra-wideband protection. Under low power density incidence, the energy selective surface generates a passband in the S-band, ensuring normal signal reception and transmission for the protected antenna. Under high power density incidence, the energy selective surface can totally reflect electromagnetic waves across the entire frequency band. Furthermore, this invention employs a rotationally symmetric structure, exhibiting polarization insensitivity. Compared with existing technologies, the energy selective surface proposed in this invention has a simpler structure, a lower profile, higher shielding effectiveness, and provides wider bandwidth protection, achieving ultra-wideband protection.

An acoustic wave device is provided comprising a substrate and at least one resonator structure of a first type and at least one resonator structure of a second type mounted on the substrate. The resonator structures of the first type are configured to operate as capacitors and have a first thickness, causing the resonator structures to have a first passband frequency range. The resonator structures of the second type have a second thickness that is different from the first thickness, causing the resonator structures to have a second passband frequency range. A method for forming such an acoustic wave device is also provided. A die comprising such an acoustic wave device, a filter comprising such an acoustic wave device, a radio-frequency module comprising such an acoustic wave device, and a wireless mobile device comprising such an acoustic wave device are also provided.

The application belongs to the technical field of signal high-speed acquisition and processing, and particularly relates to a kind of ocean absolute gravimetric metrology device interference signal high-speed acquisition and processing method, with NI PXIe-5172 digitizer as hardware, single-channel input mode is adopted, 14-bit resolution, 250MS / s sampling rate is set to collect interference signal;The collected signal is subjected to 128-tap FIR filtering processing of 5MHz-40MHz passband;Based on FPGA, multi-dimensional information fusion discrimination zero-crossing processing algorithm is realized, including double-sampling zero-crossing detection, local amplitude validity discrimination, timing consistency verification and comprehensive logic determination;Linear interpolation algorithm is used to calculate accurate time stamp for valid zero-crossing point;Combined with laser half-wavelength and time stamp sequence, the weighted least squares method is used to fit and solve the value of gravitational acceleration, and the standard deviation is calculated.

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.

A high-frequency circuit (1) is provided with: a transmission filter (31) connected to selection terminals (512 and 513), having a passband of a transmission frequency band including a frequency band (A); a reception filter (33) connected to a selection terminal (516), having a passband of a reception frequency band including the frequency band (A); and paths (P1 and P2) connecting the transmission filter (31) to the selection terminals (512 and 513), respectively, wherein a first reflection phase of the reception frequency band of the frequency band (A) when the transmission filter (31) is observed from a common terminal (511) via the path (P1) is different from a second reflection phase of the reception frequency band of the frequency band (A) when the transmission filter (31) is observed from the common terminal (511) via the path (P2), and in the transmission frequency band of the frequency band (A), a phase variation amount between the common terminal (511) and the transmission filter (31) connected via the path (P1) is smaller than a phase variation amount between the common terminal (511) and the transmission filter (31) connected via the path (P2).

Enhancing spurious rejection in an acoustic filter circuit is provided. Specifically, the filter circuit includes an acoustic bandpass filter circuit and an acoustic bandstop filter circuit. In embodiments disclosed herein, the acoustic bandpass filter circuit and the acoustic bandstop filter circuit can be integrated into either a single semiconductor die or a single system-in-package (SiP). By integrating the acoustic bandstop filter circuit with the acoustic bandpass filter circuit, it is possible to enhance spurious rejection with minimum impact on insertion loss and passband performance to thereby improve overall performance of the acoustic filter circuit. Moreover, it is possible to reduce fabrication variation and cost of the acoustic filter circuit as well.

Disclosed is a multi-band base station antenna using a selective shielding surface. The disclosed antenna comprises: a selective shielding surface which passes signals in a preset frequency band; a plurality of low-band radiators located on the selective shielding surface; a reflection plate disposed below the selective shielding surface and spaced apart from the selective shielding surface; and a plurality of high-band radiators coupled onto the reflection plate, wherein the selective shielding surface has a pass band configured to pass signals emitted from the high-band radiators and block signals emitted from the low-band radiators.

The application discloses a surface acoustic wave device and a radio frequency front-end module, and relates to the technical field of radio frequency filtering. The surface acoustic wave device comprises a piezoelectric substrate, at least one first interdigital transducer, at least one second interdigital transducer, a reflection assembly and a mass load layer; the first interdigital transducer and the second interdigital transducer are electrically connected and are arranged on the piezoelectric substrate; the reflection assembly comprises at least a first reflector; in a first direction, the first reflector is arranged between the first interdigital transducer and the second interdigital transducer, and the first direction is the arrangement direction of the first interdigital transducer and the second interdigital transducer; and the mass load layer is arranged on the side of the first reflector away from the piezoelectric substrate. The application can improve the suppression effect of a specific frequency band (for example, a frequency band close to a passband) while ensuring that the passband insertion loss is not affected.

The application discloses a kind of based on interdigital coupling and SIS multi-mode double trap wave ultra-wideband filter, comprising: dielectric plate, first component assembly fixed on the top of the dielectric plate and second structural assembly fixed on the bottom of the dielectric plate;The first component assembly includes first feed line port port, second feed line port port is oppositely arranged with the first feed line port port, is arranged between the multi-mode resonator of first feed line port port and second feed line port port and is arranged below the second trap structure of the multi-mode resonator;The multi-mode resonator includes first transmission line, second transmission line is fixedly connected on one side of first transmission line and third transmission line is fixedly connected on the other side of the first transmission line, and the end of the third transmission line away from first transmission line is away from second feed line port port.According to the application, the filter has excellent passband performance high frequency selectivity, double-frequency trap wave function, compact structure and strong processing feasibility.

The application discloses a LiNbO3-based periodic curved three-busbar structure acoustic wave resonator and a preparation method thereof, which comprises a substrate, a piezoelectric film layer arranged on the substrate, an interdigital electrode layer arranged on the piezoelectric film layer, a release hole arranged on the piezoelectric film layer, and a cavity arranged in the substrate, wherein the interdigital electrode layer is provided with symmetrically arranged interdigital electrodes, and two interdigital electrodes on the same side are connected by three parallel periodic curved busbars. The transverse excitation bulk acoustic resonator (XBAR) based on the curved three-busbar structure can effectively suppress the transverse high-order stray mode, significantly weaken the ripple in the passband, suppress the additional acoustic energy loss caused by the parasitic mode, improve the flatness and stability of the frequency response, and improve the signal transmission performance of the device. Compared with the traditional XBAR with the parallel busbar structure, the structure can effectively avoid the excitation of other non-target acoustic modes during the resonance process, thereby improving the spectral purity of the device and increasing the Q value by about 4 times compared with the traditional XBAR.

Provided are a high-frequency module and a communication device capable of reducing transmission loss degradation while enabling communication for a co-banded communication band. A high-frequency module (1) comprises a first filter (21), a second filter (22), and a switch (5). The first filter (21) has a first passband. The first passband includes a reception band of a first communication band. The second filter (22) has a second passband. The second passband includes a transmission band of the first communication band and a reception band of a second communication band. The switch (5) connects the first filter (21) and / or the second filter (22) to an antenna terminal (71). The reception band of the second communication band includes a first band and a second band. The first band is a band overlapping the reception band of the first communication band. The second band is a band overlapping the transmission band of the first communication band. The second filter (22) is a variable filter.

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.

The application discloses a band-pass filter, and relates to the field of microwave technology.The band-pass filter comprises a first shielding layer, a resonant coupling layer and a second shielding layer which are sequentially arranged from top to bottom and are made of a low-temperature co-fired ceramic process.The resonant coupling layer comprises a first coupling line, a second coupling line, four resonators arranged from left to right and three couplers;one coupler is arranged between every two adjacent resonators;the first coupling line is located above the resonators at the leftmost end and the rightmost end;the second coupling line is located below the two resonators in the middle;the resonators and the couplers are connected with ground ports;the resonator at the leftmost end is connected with an input port;the resonator at the rightmost end is connected with an output port;the first shielding layer and the second shielding layer are connected with the ground ports.The application can make the relative bandwidth of the passband less than 10%, and improve the passband performance and the stopband suppression performance.

This invention discloses a suboctave band equalization structure and a method for optimizing in-band flatness based on it, relating to the technical field of microwave circuits. The suboctave band equalization structure consists of a 50-ohm microstrip line, an absorption resistor, and a high-impedance line. The high-impedance line employs an S-shaped bend structure to reduce volume, and the absorption resistor's geometric dimensions are adjusted to precisely control the equalization depth. This invention utilizes the transmission characteristics of a resonator exhibiting high insertion loss at the center of the band and gradually decreasing insertion loss at both sides when the fundamental frequency reaches the second resonant frequency. This complements the transmission characteristics of a filter, which has low insertion loss in the center of the passband and gradually increasing insertion loss at both sides. This application can significantly improve in-band flatness by physically canceling passband edge losses through passive microstrip circuits while ensuring high matching performance with return loss better than -20dB. It has advantages such as simple structure, easy integration, and strong engineering applicability.

A high-frequency module (1) comprises: a power amplification circuit (10); a filter (31) having a passband that includes a transmission band of a band A; a filter (35) having a passband that includes a band B; a filter (34) having a passband that includes a reception band of a band C; inductors (51 and 52); and semiconductor components (41 and 43). The semiconductor component (41) includes a switch (301) that is connected to the filter (31) and the power amplification circuit (10), a switch (303) that is connected to the filter (35) and the power amplification circuit (10), and a switch (304) that is connected to the filter (35) and one end of the inductor (52). The semiconductor component (43) includes a low noise amplifier (22) and a switch (206) that is connected between the one end of the inductor (52) and the ground. One end of the inductor (51) is connected to the filter (34), and the other ends of the inductors (51 and 52) are connected to an input end of the low noise amplifier (22).

A triple-tuned radio frequency coil transceiver system and a nuclear magnetic resonance imaging device. The triple-tuned radio frequency coil transceiver system comprises a coil circuit, a first transceiver link, a second transceiver link, and a first signal filter. The first signal filter comprises a first filter and a second filter. The passband range of the first filter does not coincide with the passband range of the second filter. A first end of the first filter and a first end of the second filter are both electrically connected to the coil circuit. A second end of the first filter is electrically connected to the first transceiver link, and a second end of the second filter is electrically connected to the second transceiver link. The first transceiver link is configured to transmit and receive a first nuclide signal. The second transceiver link is configured to transmit and receive a second nuclide signal and a third nuclide signal. The coil circuit is configured to generate relaxation signals of a first nuclide, a second nuclide, and a third nuclide.

The embodiment of the application relates to the technical field of filter design, and discloses a straight-line topology structure with phase compensation characteristics, design and a superconducting filter. The topology structure is based on a standard straight-line topology structure comprising a source suspension branch, a straight-line coupling main path and a load suspension branch. Four continuous resonators are selected on the straight-line coupling main path. A first resonator and a fourth resonator of the four continuous resonators are cross-coupled to form the straight-line topology structure with the phase compensation characteristics. The four continuous resonators form a CQ structure. Therefore, under the condition of fully utilizing the simplicity of the straight-line topology structure, the introduction, independent control and adjustment of the phase compensation real zero point are realized, the group delay in the passband of the filter is compensated while the sideband suppression capability is improved, and therefore the signal fidelity of a communication system is improved.

This invention discloses a method for generating coherent broadband frequency-stepped microwave signals. The method involves electro-optically modulating an optical carrier with a microwave signal to generate a double-sideband optical signal containing only an upper sideband and a lower sideband. A dual-passband optical filter separates the upper and lower sideband signals. These signals are then frequency-shifted in opposite directions and subjected to the same delay before being fed back into the dual-passband optical filter, forming a bidirectional frequency-shifting loop. The gain of the bidirectional frequency-shifting loop is set to 1, and the coupled signals of the two frequency-shifted signals output from the loop are photoelectrically converted to generate a coherent broadband frequency-stepped microwave signal. This invention also discloses a coherent broadband frequency-stepped microwave signal generation device. Compared to existing technologies, this invention eliminates the influence of optical carrier phase noise, effectively enhances signal stability and coherence, and increases the bandwidth of the generated signal.

This invention proposes a high-performance LC high-pass filter, comprising a signal input terminal, a signal output terminal, and a common ground terminal, and further comprising a first resonant unit, a second resonant unit, a third resonant unit, a fourth resonant unit, and a fifth resonant unit connected in sequence. This invention can be used in carrier aggregation scenarios to suppress blocking interference caused by low-frequency transmitted signals to high-frequency receivers, while allowing high-frequency signals to pass through without distortion. Its steep stopband characteristics ensure extremely high suppression even at frequencies very close to the passband, effectively protecting sensitive receiving circuitry. By employing a Π-type capacitor network structure, the bandwidth of the high-pass filter is extended by 6%. Furthermore, the integrated design reduces its physical size by approximately 10%, making it highly suitable for space-constrained system applications.

This invention belongs to the field of microwave antenna and RF front-end circuit technology, specifically relating to a broadband filter dielectric resonator antenna with wide harmonic suppression characteristics and a method for controlling its radiation characteristics. The method includes the following steps: obtaining an initial electromagnetic state parameter set and performing fundamental mode field distribution decoupling calculations; constructing an open-loop feeder partially coupled topology to generate a hybrid broadband response signal set; parsing the passband envelope and attenuation determination to map a folded open-loop resonator to generate lower stopband zeros; determining the harmonic frequency band energy density threshold to trigger a multi-topology notch filter to generate an upper stopband zero array; and compensating for phase group delay and gain flatness to output the converged final radiation state parameters of the antenna. This invention overcomes the problems of multimode interference between the feed network and the radiator, the inability to independently generate stopband radiation zeros, and nonlinear phase group delay shift caused by the lack of distributed notch filter node cooperative configuration.

The application relates to an acoustic metamaterial with a frequency-doubling filtering characteristic and a shape optimization method thereof, the optimization method comprising the following steps: constructing a two-dimensional finite element simulation model, the two-dimensional finite element simulation model comprising a main plate, a thin adhesive layer and an acoustic metamaterial, the acoustic metamaterial having an initial structure, the initial structure being periodically arranged by an initial unit cell structure, and a free-shape boundary being arranged in the initial structure; constructing an optimization model according to a target that a fundamental frequency is a passband and a frequency double is a stopband; adjusting the free-shape boundary on the basis of the initial structure by using a moving asymptote method; and calculating to obtain an optimal structure of the acoustic metamaterial. Compared with the prior art, the application not only ensures that the optimization target can be achieved, but also reduces the complexity of the structure, facilitates processing and manufacturing, and the designed acoustic metamaterial has the frequency-doubling filtering characteristic, and can effectively filter the inevitable system nonlinearity in nonlinear ultrasonic Lamb wave detection.

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.

This invention discloses a surface acoustic wave (SAW) device, filter, and fabrication method using a locally convex piezoelectric thin film structure, relating to the field of integrated circuit technology. The device includes an interdigitated electrode layer and a piezoelectric thin film. A convex piezoelectric thin film structure is disposed above the piezoelectric thin film along the propagation direction of the SAW. The interdigitated electrode layer is disposed above the piezoelectric thin film and forms a bridge-like structure with the convex piezoelectric thin film structure. The convex piezoelectric thin film structure is fabricated using a pulsed laser deposition process, or by an etching process. This device significantly suppresses the excitation of lateral heterogeneous modes, thereby improving the passband performance of the device.