144 results about "Frequency selectivity" patented technology

The invention discloses a bionic TENG sensor unit for an artificial throat and a preparation method thereof, and relates to the field of artificial throats, and the sensor unit comprises a gradient micro-dome friction layer, a strain amplification layer, an electrode layer and a back cavity substrate layer. The gradient micro-dome array realizes gradual contact through gradient change of height and diameter; the strain amplification layer converts vertical vibration into horizontal strain by using a cantilever beam-sliding block structure; the back cavity array selectively amplifies vibration at a specific frequency based on the Helmholtz resonance principle. The invention further provides a corresponding preparation method. The preparation method comprises the steps of back cavity forming, electrode deposition, microstructure manufacturing, surface treatment and the like. The sensor has the advantages of high sensitivity, good frequency selectivity and strong durability, and is particularly suitable for detecting weak laryngeal vibration signals of laryngeal patients.

The invention discloses an OCT (Optical Coherence Tomography) retina image denoising method based on a high-frequency enhanced diffusion model, which is characterized in that a double-branch diffusion model network constructed based on frequency perception Fourier transform attention (FFTA) is used for separating different frequency domains, enhancing specific frequency domain features and fusing the specific frequency domain features into a spatial domain feature map to realize stronger frequency domain perception and processing capability; the invention relates to a time step T coding method for a module of frequency domain attention. The time step T of the diffusion model is used as a parameter to be coded into a frequency domain attention module to participate in self-attention matrix calculation, so that frequency domain feature processing is aligned with the iteration step number of the diffusion model, and different frequency domain information is pointedly processed at different time steps T; the frequency selective hopping mechanism uses pooling operation to obtain a high / low frequency characteristic pattern, so that the network has adaptive frequency domain retention capability for different local parts.

The invention provides a component high-frequency signal transmission quality prediction and optimization method and system, and relates to the technical field of signal transmission, and the method comprises the steps: extracting the attenuation change rate of each frequency band based on the frequency domain characteristics and transmission path physical characteristic parameters of a to-be-transmitted signal of a component, and building a correlation function with a frequency band boundary position; calculating a transmission path terminal prediction loss spectrum and determining a compensation gain coefficient; performing frequency selective amplitude adjustment on the to-be-transmitted signal; and an actual received signal is collected and compared with the target frequency domain amplitude distribution, and the correlation function is updated. According to the invention, accurate prediction and adaptive optimization of high-frequency signal transmission quality are realized, and signal transmission integrity is improved.

Wireless communications systems and methods related to wireless communications in a system are provided. A user equipment (UE) may receive from a base station (BS), an uplink (UL) scheduling grant indicating subband precoding information and a resource allocation spanning a plurality of subbands. The UE may determine a plurality of subband precoders based on the subband precoding information. Each precoder of the plurality of subband precoders may be associated with a subband of the plurality of subbands. The UE may transmit to the BS, an UL communication signal in the resource allocation using the plurality of subband precoders.

The invention belongs to the technical field of integrated circuits, and discloses a high-selectivity constant-bandwidth reconfigurable filter chip based on a GaAs (gallium arsenide) process, which comprises a dielectric substrate, a multilayer metal structure, a plurality of folded opening-shaped metal microstrip lines, a plurality of grounding metal columns, a variable capacitance diode, an MIM (metal injection molding) capacitor and the like. Resonance is realized in a mode of combining electric coupling and magnetic coupling, a variable capacitance diode is utilized to tune the center frequency, and the bandwidth is kept constant in the tuning process. Transmission zeros are introduced at two sides of a passband through cross coupling, so that the frequency selectivity and the spectrum management capability are remarkably improved, and meanwhile, the optimization of the microstrip interconnection structure effectively reduces the system loss. According to the invention, the strict requirements of a modern radio frequency communication system on miniaturization, high performance and high selectivity can be met, and extremely high adjustability and adaptability are achieved.

The invention discloses a low-voltage power line carrier communication network repeater deployment method and system, and relates to the technical field of power communication. The method comprises the following steps: (1) according to PLC network topology information, acquiring an STA set which cannot directly communicate with a CCO, and inputting model parameters; (2) calling a general optimization solver to carry out model solution to obtain a solution result; (3) if the feasible solution exists, outputting a PCO deployment mark; if not, adjusting the received signal threshold value and the transmitting power, and repeating the step (2); and (5) once a feasible solution is obtained or the model parameter reaches the set limit value, the solution is ended. According to the deployment planning model constructed by the invention, the optimal deployment position of the PCO in the network is solved by taking the minimum weighted sum of the total transmission time delay and the total cost as a target and taking the received signal strength and the single-hop relay as constraints; the problem that seamless coverage of a low-voltage power distribution network is difficult to realize by single-hop communication due to high background noise and frequency selective fading of a PLC channel is solved.

The present invention provides an interleaving method and a related device for mapping a virtual resource block to a physical resource block (VRB-to-PRB) during a sub-band full duplex (SBFD) period, and a method for mapping a virtual resource block to a physical resource block (VRB-to-PRB) during the SBFD period of the sub-band full duplex (SBFD) period of the sub-band full duplex (SBFD) period of the sub-band full duplex (SBFD) period of the sub-band full duplex (SBFD) period of the virtual resource block to the physical resource block (VRB-to-PRB). In one embodiment, the method includes performing a VRB-to-PRB interleaving during the SBFD to interleave resource blocks (RBs) and map a VRB beam to a PRB beam in a first DL frequency domain and a second DL frequency domain. By the method, the VRB-to-PRB interleaving is enhanced in the SBFD operation, thereby being able to benefit from less frequency selective fading.

The application provides a design method of a broadband multi-modal vibration suppression damping material based on fractal geometry, comprising: constructing an initial geometric configuration of the damping material, the damping material being composed of a periodic arrangement of a three-dimensional unit cell structure in a plane; layering the unit cell structure to construct a parameterized model of the unit cell structure by using a fractal dimension of the unit cell structure and layer structure parameters; constructing a vibration impedance transfer equation according to the parameterized model of the unit cell structure, determining input impedances of the innermost layer and the outermost layer, and determining vibration attenuation amounts of the unit cell structure in multi-target frequency bands by using the input impedances of the innermost layer and the outermost layer; and optimizing the configuration and the parameterized model of the unit cell structure until the vibration attenuation amounts of the unit cell structure in the multi-target frequency bands meet load platform requirements. The broadband multi-modal vibration suppression damping material based on fractal geometry constructed can realize efficient dissipation of 10-1000 Hz broadband vibration energy and solve the frequency selectivity limitation of traditional homogeneous damping materials in multi-frequency vibration suppression.

Apparatuses and methods for frequency selective beam management (FSBM). A method for operating a user equipment (UE) includes receiving first information indicating one or more channel state information (CSI) reference signal (RS) resources for FSBM and receiving second information indicating a correspondence between the one or more CSI-RS resources and a plurality of frequency subbands. The method further includes determining, based on the first information, the one or more CSI-RS resources for FSBM and identifying, based on the second information, the correspondence between the one or more CSI-RS resources and the plurality of frequency subbands.

The present disclosure provides a signal generation method, device and communication system, relating to the technical field of wireless communication and terminal. The method comprises: generating a first binary keying signal OOK waveform based on a low-power wake-up LP-WUS signal, replacing part of the waveform of each period in the first OOK waveform with a constant modulus sequence to obtain a target waveform, the constant modulus sequence being a group of sequences with the same modulus but different phases. According to the embodiment of the present disclosure, the first OOK waveform generated based on the LP-WUS signal can be scattered, the frequency diversity gain of the LP-WUS signal is improved, a similar spread spectrum effect is formed, so that the signal can still have good performance when passing through a frequency selective fading channel (such as TDL-C), so as to improve the detection accuracy and detection efficiency of the LP-WUS signal, and further improve the synchronization of NR reception and reduce energy loss.

This invention discloses a single-polarization broadband signal anti-reflection power-generating glass, an etching method, and an installation method, relating to the fields of communication and photovoltaic power generation technology. The power-generating glass includes an ultra-clear glass substrate and a plurality of single-segment thin-film solar cells connected in series within a layer of the ultra-clear glass substrate. Each single-segment thin-film solar cell includes a positive electrode, a power-generating thin film layer, and a back electrode. The positive electrode, power-generating thin film layer, and back electrode are sequentially stacked and bonded along the thickness direction of the ultra-clear glass substrate, and each is etched with periodically arranged rectangular patterns. The long side of each rectangular pattern is horizontal, forming a frequency-selective surface for the penetration of vertically polarized electromagnetic signals. This invention, by etching rectangular patterns on the power-generating glass, achieves efficient transmission of signals in the target frequency band while ensuring power generation functionality, solving the problem of traditional power-generating glass blocking communication signals and improving the quality of broadband signal transmission.

A method for making an uncoated fine mesh design on a coated surface. The aim of this design is to completely or partially reflect or transmit specific frequencies of the electromagnetic spectrum. Such design is referred to as a frequency selective surface (FSS). More particularly, the invention relates to masking a portion of the surface of the substrate prior to deposition of the coating and later removing the mask by water washing in the process, leaving the designed fine mesh FSS pattern.

This invention discloses a bandpass frequency-selective surface structure based on strongly coupled pairs, composed of multiple basic structural units. Each basic structural unit has a vertically symmetrical structure along its thickness direction. Both the upper and lower symmetrical portions include a first metal layer and a first dielectric layer in symmetrical positions. The first metal layer contains a first resonator pair, a second resonator pair, and a third resonator pair, each using metal patches as resonators. A second metal layer and a second dielectric layer, separated along the thickness direction of the basic structural unit and in asymmetrical positions, are disposed between the upper and lower symmetrical portions. The upper and lower symmetrical portions are connected by metal conductive posts. This invention operates stably at a center frequency of 5 GHz, introduces four transmission zeros, achieves a fourth-order frequency response within 8.4% of the relative bandwidth, has an insertion loss of less than 0.49 dB, and 40° angular stability, exhibiting superior performance.

A method of estimating a channel by a reception apparatus in a wireless communication system, includes estimating a reception channel based on a received signal; determining a signal-to-noise ratio (SNR) of the received signal; estimating a frequency selectivity of the reception channel; determining a moving average filter based on the SNR and the frequency selectivity; and applying the determined moving average filter to the estimated reception channel.

The application provides a high-selectivity and simple-structure filter power amplifier and radio frequency integrated circuit, and relates to the field of power semiconductor devices.The application provides stable gate and drain bias voltages for the power amplifier transistor through a gate DC bias network and a drain DC bias network, and guarantees stable operation of the device.The input end and the output end impedance matching network are symmetrically arranged around the power amplifier transistor, both of which contain the same filter impedance transformer, and the layout is compact and simple, without additional independent filter module, effectively simplifying the circuit structure and improving the miniaturization level.Further, the filter impedance transformer is formed by cascading two λ / 4 parallel coupled microstrip lines and is matched with a λ / 2 open microstrip line, and based on the transmission line impedance transformation principle, the filter impedance transformer realizes fundamental real impedance matching, reduces signal transmission loss, forms transmission zero points in the stop band, and significantly improves the frequency selectivity.The overall circuit has high integration, excellent performance, and good engineering application and promotion value.

The application discloses a kind of OFDM-PON bits and power loading method based on layered modulation, belong to passive optical network field.The application includes: based on the signal-to-noise ratio between each branch optical network unit and optical line terminal in OFDM-PON, each optical network unit is grouped;Low-order quadrature phase modulation modulation format is used as base layer in the optical network unit group with low signal-to-noise ratio, high-order quadrature amplitude phase modulation-16 and quadrature amplitude phase modulation-64 modulation format are used as enhancement layer in the optical network unit group with high signal-to-noise ratio;The trough point of the frequency selective fading of each group optical network unit in OFDM-PON is calculated;According to bit allocation method, power allocation method is carried out for bit allocation and power allocation of base layer and enhancement layer.The application realizes the maximum utilization of flexible OFDM-PON in channel condition by simple and easy-to-implement algorithm, to realize the increase of overall OFDM-PON system capacity, satisfy future optical access network to the full use of channel power abundance.

The invention discloses a channel estimation method, related equipment, a storage medium and a computer program product. The method comprises the steps that a sending device determines a first symbol and first information, the first symbol is used for indicating semantics of an information source, and the first information is used for indicating the importance degree of the first symbol on information source reconstruction; in the process of superposing a second symbol to the first symbol, power is allocated for the first symbol and the second symbol based on the first information, and the second symbol is used for channel estimation; and sending the superposed first symbol to a receiving device through a first channel, the first channel having at least the characteristics of time selective fading and frequency selective fading. According to the technical scheme provided by the invention, under the scene of double selective channels, the pilot symbols are superposed on the semantic symbols, and the distribution of the pilot power is dynamically adjusted in combination with the importance of the semantic symbols, so that more accurate channel estimation and stronger anti-interference capability can be realized.

The invention relates to the technical field of acoustic diffusion, in particular to an acoustic number theory diffuser of a composite Helmholtz resonator unit and a design method. The acoustic number theory diffuser of the composite Helmholtz resonator unit comprises at least one Helmholtz resonator unit and at least one bottom containing cavity, and the Helmholtz resonator unit is composed of at least two Helmholtz resonators and installed in the bottom containing cavity to form an acoustic diffusion module of a specific structure. Comprising a first cavity structure formed by Helmholtz resonator units, a second cavity structure formed by the Helmholtz resonator units and the wall surface of the accommodating cavity, and a third cavity structure formed by the Helmholtz resonator units and the opening of the accommodating cavity. According to the acoustic diffuser, a good acoustic diffusion effect can be generated in a wider frequency range, the problems that a traditional acoustic diffuser is high in frequency selectivity and high in structural size correlation are solved, and the acoustic diffuser is small in structural size, simple in design and suitable for being used in a small-size acoustic environment.

This application provides a method for identifying electricity consumption anomalies in electricity meters based on an HPLC communication unit, belonging to the field of electricity consumption anomaly identification technology. The method includes: the HPLC communication unit collecting electricity consumption data from the electricity meter and reporting it to the power distribution manager; when the power distribution manager determines whether electricity consumption data has not been received, it generates a missing marker for the current collection period; after generating the missing marker for the current collection period, it retrieves multiple main carrier frequency point numbers from when the electricity meter successfully reported before the current collection period to determine the environmentally adaptive stable frequency point; it instructs the HPLC communication unit to switch to the environmentally adaptive stable frequency point and perform supplementary collection from the electricity meter; if no electricity consumption data is received within the supplementary waiting time, it is determined that the electricity meter has experienced an offline anomaly during electricity consumption. This method can accurately distinguish between occasional missing electricity consumption data and real offline anomalies of the electricity meter under the influence of frequency selective fading in HPLC power line carrier communication.

Various embodiments disclosed herein relate to a low-E film using patterns for selectively transmitting or blocking electromagnetic waves according to frequency, the low-E film comprising: an insulating layer made of an insulating material; and a metal coating layer obtained by coating one surface of the insulating layer with a metal or metal oxide. The metal coating layer includes a plurality of unit cells having a polygonal shape and repeatedly arranged in rows and columns, and each of the plurality of unit cells includes patterns formed by partially removing the metal coating layer. The patterns include: a shielding pattern that forms a shielding region including the center of the unit cell in order to block electromagnetic waves in a specific frequency band; and a transmission pattern that is formed in a transmission region, which is a region of the unit cell other than the shielding region, in order to transmit electromagnetic waves in frequency bands other than the specific frequency band.

A method is disclosed for reduction of peak-to-average power ratio (PAPR) of transmission of a multiple-input multiple-output (MIMO) signal from a transmitter, wherein the transmission comprises a number of MIMO layers. The method comprises determining a clipping signal for the MIMO signal, and generating a PAPR reduced MIMO signal for transmission by combining the MIMO signal with a projection of the clipping signal onto a null space of an effective channel. The effective channel comprises a propagation channel between the transmitter and one or more receivers (wherein the receivers have an amount of receiver antenna ports) as affected by receiver combining matching transmitter precoding. A setting of the transmitter precoding is varied over frequency, which induces frequency selectivity of the effective channel. The method is particularly useful when the propagation channel is relatively flat in frequency. Corresponding computer program product, apparatus, radio access node, user device, control node, and system are also disclosed.

The application discloses a kind of bionic TENG sensor unit for artificial throat and preparation method thereof, it is related to artificial throat field, the sensor unit includes gradient microdome friction layer, strain amplification layer, electrode layer and back cavity substrate layer.Gradient microdome array realizes progressive contact by the gradient change of height diameter;Strain amplification layer utilizes cantilever beam-sliding block structure to convert vertical vibration into horizontal strain;Back cavity array is selectively amplified to specific frequency vibration based on Helmholtz resonance principle.The application also provides a corresponding preparation method, including back cavity forming, electrode deposition, microstructure manufacturing and surface treatment and the like steps.The sensor has the advantages of high sensitivity, good frequency selectivity and strong durability, and is particularly suitable for detecting weak laryngeal vibration signals of laryngeal patients.

The invention provides a power distribution transmission method and device under an OCDM frequency selection channel, and the method comprises the steps: converting a time domain signal into a frequency domain through a discrete Fourier transform matrix at a transmitting end, generating a power distribution matrix through combining channel state information and adopting a water injection algorithm, and carrying out the dynamic power precoding of a frequency domain subcarrier; generating a time domain OCDM signal through an inverse discrete Fourier transform matrix and an inverse discrete Fresnel transform matrix, adding a cyclic prefix, and transmitting the time domain OCDM signal; after a receiving end is subjected to prefix removal, a discrete Fourier transform matrix is converted into a frequency domain, a frequency domain equalizer is designed on the basis of a minimum mean square error criterion by utilizing channel diagonalization characteristics, signals are equalized in combination with transmitting power information, and finally time domain information is recovered through an inverse discrete Fourier transform matrix; therefore, the problem of traditional power distribution failure caused by OCDM channel energy dispersion is solved, and through receiving and transmitting joint optimization, diversity gain is fully mined, frequency selective channel fading is adaptively matched, the anti-interference and anti-multipath capabilities of the system are improved, and the spectrum efficiency and the transmission performance are maximized.

A method compensates for leakage currents in a protective conductor of an electrical power converter. The method includes: using a first differential current sensor for determining a differential current depending on a phase conductor current in a phase conductor and a neutral conductor current in a neutral conductor; feeding a compensation current into the phase conductor and / or into the neutral conductor via a first compensation circuit; using a second differential current sensor for capturing a signal representing remaining residual leakage current; converting the signal representing the residual leakage current to a frequency domain; generating a compensation signal for the residual leakage current in a frequency-selective manner; converting the compensation signal to a time domain; supplying the converted compensation signal converted to the first compensation circuit or a second compensation circuit; and feeding a residual compensation current corresponding to the compensation signal into the phase conductor(s) and / or into the neutral conductor.

The present disclosure provides a protective enclosure for electronic systems integrating two key components: a preconfigurable polymer matrix and a tunable metamaterial. The polymer matrix forms a lightweight, structurally robust foundation with excellent mechanical properties and design flexibility, configurable for specific application requirements. Integrated within this matrix is a highly adaptable metamaterial system, precisely tunable to interact with electromagnetic energy in customized ways. By adjusting its permittivity and permeability, the metamaterial can selectively repel or absorb specific frequencies of electromagnetic radiation, allowing targeted shielding against harmful interference while permitting desired communication signals to pass through. This integration overcomes limitations of traditional electromagnetic shielding approaches, offering enhanced design flexibility and customization for various electronic applications. The use of carbon nanoparticles enables fine-grained control over the metamaterial's electromagnetic properties, creating protective enclosures that effectively manage electromagnetic energy while remaining lightweight and mechanically robust.

A multi-stage fluidic oscillating circuit and system can produce an output spray of selectively varying frequency, even though the fluid supplied to the circuit / system is maintained at a substantially constant pressure. The circuit is characterized by two successive stages, each having a power nozzle aligned around a central axis. Upstream and downstream inertance loops are included in each of the stages, with fluid from one of these loops being selectively released to affect the frequency change in the output spray. The circuit is also characterized by a splitter and optional dog ear style protrusions formed in the outlet of the circuit.

This invention discloses a multi-spectral compatible reflective electrochromic thin-film device with an integrated frequency-selective surface and its fabrication method. The device employs a fully flexible stacked structure, consisting of, from top to bottom: a frequency-selective surface, a transparent encapsulation dielectric layer, an electrochromic working electrode, an electrolyte layer, a counter electrode, and a bottom encapsulation film. This invention utilizes a frequency-selective surface prepared through simple solution processes such as spraying for spatial impedance matching, combined with the efficient electromagnetic dissipation of the transparent dielectric layer, significantly reducing the device thickness and achieving polarization-insensitive broadband microwave absorption. This device overcomes the radar reflection contamination problem caused by the underlying metal in traditional electrochromic devices, achieving omnidirectional stable electromagnetic protection while ensuring high transmittance in the visible light band and dynamic multi-color state control. This invention combines low cost, ultra-thin conformal design, and multi-spectral compatibility, making it suitable for integrated intelligent control and microwave protection scenarios.

This invention provides an adjustable notch filter based on a ridge waveguide SSPP structure, relating to the field of wireless communication technology. By introducing independent planar adjustable notch units into the ridge waveguide SSPP structure, the notch frequency can be continuously adjusted without compromising the surface wave propagation characteristics and frequency-selective transmission response of the SSPP. The SSPP structure is formed by periodically etching multiple grooves along the propagation direction on a metal ridge, with continuous portions of the metal ridge maintained between adjacent grooves. These periodic grooves modulate the dispersion characteristics of the electromagnetic field within the ridge waveguide, enabling the ridge waveguide to support equivalent surface plasmon wave propagation, thereby forming a stable frequency-selective transmission response within a predetermined frequency range. The planar adjustable notch unit constructs a main transmission path and a secondary transmission path, utilizing the destructive interference of the two paths at a specific frequency to create a notch effect. Simultaneously, by changing the equivalent capacitance value of the varactor diode, the notch frequency can be continuously adjusted within the predetermined frequency range.

A communication method and apparatus are disclosed, applicable to the field of communication technology. The method includes: a network device sending first information to a terminal device, the first information indicating the transmission precoding matrix corresponding to each of M sub-bands, wherein the M sub-bands belong to N sub-bands, and the N sub-bands are frequency domain resources for communication between the terminal device and the network device, where N is greater than or equal to M, and M is an integer greater than 1. Through this application, the network device can configure the transmission precoding matrix at the sub-band granularity for the terminal device, adapting to the frequency-selective fading of the channel and improving communication performance. When N is less than M, the network device can indicate the transmission precoding matrix corresponding to each of some of the N sub-bands, without needing to indicate the transmission precoding matrix corresponding to each of all sub-bands, thus reducing indication overhead and blind detection complexity on the terminal device side.

The present application belongs to the technical field of radio spectrum monitoring, and provides a wide-frequency unmanned aerial vehicle spectrum detection and rapid identification method based on deep learning, which comprises the following steps: collecting wide-frequency radio signals to form a composite signal sequence and converting the composite signal sequence into a time-frequency feature map, performing cepstrum transformation on the original signal to extract a cepstrum time delay peak, constructing an environment compensation parameter vector, identifying frequency selective fading notches in the time-frequency feature map, dividing to form a spectrum fragment set, constructing a fragment association model in combination with a frequency domain spacing and an inverse frequency position matching rule, and completing physical constraints, inputting the spectrum fragment spatial features and the environment compensation parameter vector into the model, calculating a coherence weight through a deep fragment association model based on a Transform architecture, completing logical reorganization of the spectrum fragments in a vector space and generating a logical reorganization vector, inputting the vector into a double-branch parallel classification network, and realizing accurate identification of unmanned aerial vehicle target models and communication protocols.