66 results about "Comb filter" patented technology

A method performed by a programmed processor of an audio system, the method includes retrieving a head-related transfer function (HRTF) dataset from memory, processing the HRTF dataset to remote comb filtering effects during audio playback; applying, to each HRTF in the processed HRTF dataset, a gain to increase a magnitude of the HRTF at a frequency range; and storing the processed HRTF dataset in memory.

The invention discloses a high-order digital decimation filter with a variable decimation multiple, which comprises a cascade comb filter used for downsampling and anti-aliasing filtering, filtering high-frequency components and obtaining low-frequency density signals, and a compensation filter connected to the output end of the cascade comb filter and used for compensating passband attenuation and performing double decimation on the signals, and the output end of the compensation filter is connected with a half-band filter for realizing third-stage signal extraction. The invention further discloses a filtering method of the high-order digital decimation filter with the variable decimation multiple. Aiming at the defects that a traditional single-stage FIR filter is high in hardware requirement, complex in design, high in filter order and not easy to implement and the like, and aiming at the defect that a CIC filter is insufficient in passband flatness, a CFIR compensation filter is used for compensation, and finally a half-band filter is used for frequency reduction.

The invention discloses a cone motion test data processing method based on parallel calculation and harmonic wavelet filtering, and the method comprises the steps: collecting an original voltage signal matrix measured by a wind tunnel force measurement six-component balance through a data collection system when a test model carries out the cone motion in a cone motion wind tunnel test; a principal coefficient matrix and a secondary coefficient matrix are constructed by using a six-component balance formula matrix, and a parallel resolving matrix is constructed by using the principal coefficient matrix and an original voltage signal matrix; iteratively solving a time-domain balance load matrix at each moment in the conical motion wind tunnel test based on the original voltage signal matrix, the principal coefficient matrix, the secondary coefficient matrix and the parallel solution matrix; the method comprises the following steps: determining the center frequency of a harmonic wavelet according to the prior information of a conical motion wind tunnel test, constructing a generalized harmonic wavelet, constructing a comb filter in a frequency domain based on the generalized harmonic wavelet, filtering a frequency domain balance load matrix by using the constructed comb filter, and then converting the frequency domain balance load matrix into a time domain, thereby completing the extraction and reconstruction of load data.

The present application provides a directional sound pickup method, system, device, and storage medium, relating to the field of sound pickup. The method comprises: performing MVDR beamforming processing on the initial speech signal input by the microphone array, and then extracting the BFCC features and fundamental frequency features of the speech signal. The BFCC features are processed using a pre-trained speech / noise separation DNN to obtain a time-frequency mask. Comb filter parameters are adaptively designed based on the fundamental frequency features, and the initial speech signal is comb filtered. The time-frequency mask is used as a weighting coefficient and multiplied with the comb-filtered speech signal and the initial speech signal, respectively, to estimate the target speech energy and noise energy. The frequency-dependent Bark gain coefficient is calculated on the Bark frequency scale and used to enhance the speech signal in the time-frequency domain. Finally, the enhanced speech signal is converted into a time-domain signal through an inverse BFCC transform to obtain the target enhanced speech pointing in the target direction. The above scheme improves the directional sound pickup effect.

The invention relates to the technical field of data acquisition, in particular to a data acquisition method and system for a high-low voltage transformer substation. The method comprises the following steps: acquiring an original electrical signal sequence, calculating an initial integer sampling point number based on a zero crossing point interval, determining a fundamental wave period by carrying out autocorrelation operation on the original electrical signal sequence in a preset window taking the fundamental wave period as a center, and obtaining a signal after primary filtering by adopting first comb filtering taking the fundamental wave period as a delay parameter; and performing short-time Fourier transform on the signal after primary filtering, forming a non-integer harmonic frequency point set in a preset non-harmonic frequency band, constructing a second filtering link according to the non-integer harmonic frequency point set, and filtering non-integer harmonics in the signal after primary filtering to obtain collected data. According to the scheme, the fundamental wave period can be accurately determined to deeply suppress the integer harmonics, the non-integer harmonics can be recognized and filtered out in the environment with the low signal-to-noise ratio, and meanwhile original signal damage is avoided.

The invention provides a digital filter, a parameter configuration method and a chip. The digital filter comprises a multi-order sinc filter and a multi-order comb filter which are connected, the order N and the down-sampling rate of the multi-order sinc filter, the order b of the multi-order comb filter and a plurality of corresponding weight coefficients are pre-determined and configured according to the frequency to be filtered; the multi-order sinc filter receives the coded signal, samples the coded signal for N times according to a preset down-sampling rate, and calculates an average value of each sampling result to obtain an average value signal; the multi-order comb filter performs weighting operation on the mean value signal through the first signal processing unit, the second signal processing unit and the corresponding weight coefficients, and sums the mean value signal through the accumulator to obtain an output signal; the output signal is a coded signal after the signal with the frequency to be filtered is filtered. The parameters of the digital filter are flexibly configured based on different application scenes.

The invention provides a tumor in-situ pathology detection system based on an endoscopic multi-mode probe. The tumor in-situ pathology detection system comprises a main controller, an SC laser, a DUV laser, a comb filter, a polarizer, a microarray lens, a multiplexing beam combiner, a conjugate coupling module, an endoscopic optical fiber bundle, a FAST optical fiber bundle, an SC spectrograph and a DUV spectrograph. Aiming at G14-level bronchial navigation surgical robot in-situ pathology detection, the invention provides a detection system based on an endoscopic multi-mode optical probe, FAST hyperspectral image spectrum integrated detection of SC, DUVRS, DUVLIF and mIHC can be realized, a multi-mode hyperspectral fusion image reflecting spatial distribution of histochemical components of a diagnosis point and corresponding spectral feature data are output, and the detection system is used for detecting the in-situ pathology of the G14-level bronchial navigation surgical robot. And real-time, accurate and multi-mode data or information is provided for diagnosis of doctors.

The application discloses a kind of electric energy metering system and method with magnetic field anti-interference ability, belong to electric energy metering technical field.The system includes current connection terminal, multi-winding current transformer, first analog-digital conversion unit, voltage connection terminal, voltage division conversion unit, second analog-digital conversion unit and electric energy metering unit, further include external magnetic field detection unit, active compensation control unit and micro power amplifier.The multi-winding current transformer of the application adopts the structure of double magnetic core+multi-winding, which can effectively detect magnetic field interference current, and also can realize accurate compensation, and has the advantages of simple structure, small size, etc.The active compensation control unit of the application accurately extracts interference signals through multi-stage feedback filter and four-stage comb filter, and combines active compensation control, which can effectively suppress the interference components in the difference current and ensure the accuracy of measurement.

The invention provides a communication antenna steering control system and method, and relates to the technical field of antenna control, and the system comprises a parameter configuration module which is used for obtaining the initial state of a communication antenna, and collecting hardware state information in real time; the signal capturing and tracking module is used for configuring the initial frequency of the numerical control oscillator, starting the parallel correlator group to scan the carrier frequency and calculating frequency domain power spectrum data; and the angle calculation module is used for mapping the resampling phase difference and the baseline parameter into an azimuth angle based on a quaternion solution, and superposing IMU angular velocity data for dynamic compensation. According to the invention, a multi-stage phase-locked loop architecture, a dynamic threshold adaptive algorithm, cascade frequency division coefficient compensation and an FIR comb filter are adopted, so that high-sensitivity acquisition of signals in a broadband is realized; an extended Kalman filtering algorithm and a mechanical lag compensation algorithm are fused, so that the phase lag of the steering engine system is greatly reduced; and in combination with real-time fusion of the IMU angular velocity, the system can still keep relatively high pointing precision in a dynamic scene.

The invention relates to a method for reducing the bias in a periodic signal having a theoretically zero mean value and provided by a sensor associated with a rotary electric machine, in particular by a sensor for determining the angular position of a rotor of a rotary electric machine, the method comprising: - receiving the signal provided by the sensor; - multiplying this signal by a signal proportional to the rotational speed of the rotor of the rotary electric machine in order to obtain a first signal; - at least one integration over half a period of the first signal in order to obtain a second signal; - applying, to the second signal, a finite impulse response filter, in particular a comb filter, so as to add, to the second signal, a delayed version of this second signal in order to obtain a third signal representative of the bias, in particular equal to the bias of the signal provided by the sensor; and - subtracting the third signal from the signal provided by the sensor, so as to reduce the bias in this signal provided by the sensor.

A method operates a hearing aid, in particular a classic hearing aid. The hearing aid includes an input transducer, a signal processing device, and an output transducer. Wherein an occurrence of a comb filter effect is determined by the signal processing device, and wherein a countermeasure is controlled by the signal processing device as a function of the determined occurrence of the comb filter effect.

The invention relates to the technical field of railway electric traction transmission, in particular to an irregular wheel wear detection method based on stator current analysis, which comprises the following steps of: constructing an electromechanical coupling model of a high-speed train traction transmission system based on a traction variable-current driving model and a train-track coupling power model; secondly, based on an electromechanical coupling model, the influence of irregular wear of the wheel on electrical parameters in an electric driving system is analyzed, and the frequency relation between irregular wear excitation and the electrical parameters (stator harmonic current) is established; and by constructing a comb filter based on variable mode decomposition, accurate capture of wheel wear related harmonic waves in stator current is realized, so that irregular wear of the wheel is detected, additional installation of a sensor is not needed, the cost is low, the method is not liable to be interfered by the external environment, and the method has relatively good engineering applicability.

The present invention relates to a Mach-Zehnder interferometer cascade comb filter and a wavelength division multiplexer / demultiplexer to solve the technical problems of wavelength sensitivity introduced by the wavelength division multiplexer of the existing cascade Mach-Zehnder interferometer and its unsuitability for transverse magnetic waves. The filter comprises n-stage comb filter units connected in series, and the m-th stage comb filter unit comprises 2 m A comb filter is provided, each comb filter includes a Mach-Zehnder interferometer, and the Mach-Zehnder interferometer includes a first optical coupling component, a transmission waveguide, and a second optical coupling component arranged in sequence along the transmission direction of the light wave; the first transmission waveguide in the transmission waveguide is provided with a phase delay waveguide, and after TE polarized light and TM polarized light pass through the phase delay waveguide, the phase difference between the TE polarization and the TM polarization is 2πA, where A is a positive integer, and the group refractive index difference between the TE polarization and the TM polarization is within 15%.

When an observation signal including noise the pitch of which changes with the passage of time has been received, a comb filter selection unit (21) selects, from a plurality of comb filters having different pitches to be removed, a comb filter having a pitch to be removed, which matches the pitch of noise, as a selected comb filter in response to the change of the pitch of the noise with the passage of time. A comb filter application unit (23) applies the selected comb filter to the observation signal to remove noise from the observation signal.

The application relates to a digital wave trap, a digital low-pass filter and a design method, a medium and an electronic device. The digital wave trap comprises a wave limit boundary anchoring unit and a wave limit zero point modulation unit which are cascaded in sequence, the wave limit boundary anchoring unit adopts a cascaded integral comb filter structure and is used for generating a first attenuation zero point at a boundary frequency of a target wave trap frequency band; the wave limit zero point modulation unit adopts a finite-length unit impulse response filter structure and is used for generating at least one second attenuation zero point in the target wave trap frequency band; and a continuous suppression band for the target wave trap frequency band is formed in the amplitude-frequency response of an output signal of the wave limit zero point modulation unit by the first attenuation zero point and the at least one second attenuation zero point. By using the digital wave trap provided by the application, a digital low-pass filter which can deeply and widely suppress power frequency interference and maintain strict linear phase and excellent low-pass characteristics can be designed without significantly increasing hardware resources and power consumption.

The invention relates to underwater acoustic signal processing, in particular to a low signal-to-noise ratio underwater acoustic line spectrum enhancement system based on deep learning, which comprises a learnable comb filter module, and is characterized in that a series of learnable multi-channel comb filters with fixed frequency are constructed through a convolutional layer to scan input signals, enhance target frequency and attenuate non-target frequency; the channel fusion module is used for carrying out feature extraction and feature fusion on the output signal of the multi-channel comb filter; the frequency estimation module is used for identifying the line spectrum component of the target frequency from the feature map output by the channel fusion module, screening the frequency bin by introducing a learnable threshold parameter, and generating a frequency index of each frame; the mask enhancement module is used for carrying out adaptive filtering on the input signal by utilizing the frequency index sequence output by the frequency estimation module; according to the technical scheme provided by the invention, the defect of insufficient line spectrum enhancement capability in a complex ocean noise environment in the prior art can be effectively overcome.

A method for reducing bias in a periodic signal with a theoretically zero average value provided by a sensor associated with a rotating electrical machine, in particular by a sensor for determining the angular position of a rotating electrical machine rotor, the method comprising: - receiving the signal provided by the sensor - multiplying this signal by a signal proportional to the rotational speed of the rotating electrical machine rotor to obtain a first signal - at least one integration over half a period of the first signal to obtain a second signal - applying a finite impulse response filter to the second signal, in particular a comb filter, to add a delayed version of this second signal to obtain a third signal representative of the bias, in particular equal to the bias of the signal provided by the sensor, and - subtracting the third signal from the signal provided by the sensor.in order to reduce the bias of this signal provided by the sensor. Abbreviated figure: Fig 3,

The invention discloses a body feeling myoelectricity artificial hand system fusing myoelectricity enhanced decoding and bionic electrical stimulation feedback. The system comprises a myoelectricity bracelet, a main controller, an electrical stimulator and an artificial hand. According to the system, an electromyographic bracelet is used for collecting residual limb side electromyographic signals, a main controller removes electrical stimulation artifacts in the signals in real time through a comb filtering and self-adaptive filtering series algorithm, gesture intentions are recognized online through a self-updating multi-class LDA algorithm, and the prosthetic hand is driven to execute corresponding actions. According to the system, a closed-loop feedback mechanism based on a muscle shuttle sensing model is constructed, the muscle shuttle sensing model simulates neural coding characteristics of a human body muscle shuttle, the real-time stroke of a micro servo electric cylinder of the prosthetic hand and stress information of a torque sensor are mapped into electrical stimulation frequency and voltage parameters respectively, and an electrical stimulator is controlled to apply bionic stimulation to the stump. According to the invention, closed-loop control of myoelectricity intention recognition, artificial limb action execution, state detection and electrical stimulation feedback is realized, the problems of lack of sensory feedback, serious electrical stimulation signal interference and the like of the existing myoelectricity artificial limb are effectively solved, a patient is helped to reconstruct ontology perception, and the accuracy and naturalness of artificial limb control are improved.

The utility model relates to the technical field of optical communication, in particular to an optical filter and optical communication equipment. The optical filter comprises a first polarization output assembly used for converting input light input from a first side into single polarized light and outputting the single polarized light, and the single polarized light has a target polarization direction; the polarizing beam splitter is located on the second side of the first polarization output assembly, the second side is opposite to the first side, and the polarizing beam splitter can transmit light in the target polarization direction and reflect light in other polarization directions; and the two comb filters are respectively positioned in two mutually vertical light emitting directions of the polarizing beam splitter, the filtering wavelength of each comb filter is adjustable, and each comb filter comprises a G-T resonant cavity. The optical filter provided by the utility model is simple in optical path and compact in structure, facilitates reduction of optical loss in an optical system, and is also easy to maintain and adjust.

The present invention discloses a blood oxygen saturation estimation method and system based on PPG signals, which relate to the technical field of blood oxygen saturation estimation and include the following steps: S1: designing a bandpass filter based on a Butterworth filter, designing a comb filter based on the characteristics of motion artifacts in PPG signals, and removing motion artifacts in the PPG signals by using the bandpass filter and the comb filter; S2: performing preliminary screening of PGG signal features by a threshold filtering method based on a correlation coefficient; S3: performing wrapping method feature screening from three dimensions of time domain, frequency domain and statistics by a recursive feature elimination method, and extracting a PGG signal feature set; S4: estimating the PGG signal feature set by an integrated regressor based on a random forest algorithm; and being able to extract blood oxygen saturation information from human PPG signals and realize real-time blood oxygen saturation monitoring.

The application discloses a device for realizing low-frequency wideband sound absorption of a small-space acoustic test box, which comprises a box body, and a composite sound absorption layer is arranged on the inner wall of the box body, characterized in that the composite sound absorption layer comprises multiple air layers for sequentially propagating sound, a micro-slit plate is arranged on the sound input side of each air layer, and a porous sound absorption material and a bottom closed flat plate are arranged on the sound output side of the air layer for finally propagating sound. The size of the small-space acoustic test box is optimized by calculating the normal frequency distribution, the degeneration of low-frequency vibration modes is avoided, and the irregular distribution of low-frequency normal vibration mode frequencies is optimized. The low-frequency sound dyeing and comb filter effect in the small-space acoustic test box are reduced, and a high-fidelity sound test signal acquisition environment is realized.

This application discloses an adaptive cancellation method and system for stator partial discharge signals to eliminate rotating excitation interference, belonging to the field of generator online monitoring technology. The method includes: determining the fundamental frequency and harmonic frequencies of the excitation interference at the current moment based on a synchronization reference signal to construct an interference frequency set; constructing an adaptive comb filter using the interference frequency set to filter the original partial discharge signal, obtaining a comb-filtered signal; performing a time-frequency transformation on the comb-filtered signal to obtain a time-frequency spectrum and identifying the time-frequency region corresponding to the interference frequency set, constructing an adaptive time-frequency masking template based on the time-frequency region, and masking the time-frequency spectrum using the adaptive time-frequency masking template to obtain a masked time-frequency spectrum; and performing an inverse time-frequency transformation on the masked time-frequency spectrum to obtain a partial discharge pulse signal that suppresses excitation interference. This invention can solve the technical problem of strong rotating excitation interference in generator partial discharge monitoring in existing technologies.

To reduce comb filtering in the ipsilateral when rendering binaural audio from plural virtual speakers on, for example, headphones, the ipsilateral delays of the ITDs of the respective speakers can be reduced to zero and the contralateral delays increased to maintain the same temporal length of the ITDs, shifting the delays to the less important contralateral ear.

The application provides a communication antenna steering control system and method, and relates to the technical field of antenna control, and comprises the following: a parameter configuration module, which is used for acquiring the initial state of a communication antenna and collecting hardware state information in real time; a signal capture and tracking module, which is used for configuring the initial frequency of a digital control oscillator, starting a parallel correlator group to scan the carrier frequency, and calculating frequency domain power spectrum data; and an angle calculation module, which maps the resampling phase difference and baseline parameters to an azimuth angle based on quaternion solution, and superimposes IMU angular velocity data for dynamic compensation. The application realizes high sensitivity capture of signals in a wide frequency band by adopting a multi-stage phase-locked loop architecture, a dynamic threshold adaptive algorithm, a cascaded frequency division coefficient compensation and a FIR comb filter; greatly reduces the phase lag of a steering engine system by fusing extended Kalman filtering and mechanical hysteresis compensation algorithms; and makes the system still maintain high pointing accuracy in a dynamic scene by combining real-time fusion of IMU angular velocity.

The invention discloses a milling chatter feature extraction method based on synchronous hierarchical entropy, and aims to extract milling chatter features from synchronous vibration data so as to better describe and analyze milling chatter. The method specifically comprises the following operation steps: selecting the type and the installation position of a sensor, and setting related parameters; acquiring synchronous vibration data X; determining n layers of decomposition operators and nodes; performing n-layer decomposition on the synchronous vibration data X to obtain # imgabs0 # low-frequency components and # imgabs0 # high-frequency components, and regarding each component as a node; respectively calculating the synchronous hierarchical entropy of each node obtained by decomposition of each layer; and taking the calculated # imgabs1 # synchronous hierarchy entropy as a flutter characteristic. According to the method, the chatter characteristics are considered, the synchronous vibration data are subjected to multi-level comb filtering decomposition to obtain a plurality of decomposition components, so that a plurality of chatter characteristics can be obtained, and the chatter can be represented more accurately. The method can be applied to milling chatter analysis and recognition, and has high practical application value.

The embodiment of the invention provides an interpolation filter circuit, a circuit module and a chip, the interpolation filter circuit comprises a compensation filter and an integrator comb filter, the compensation filter is used for carrying out first interpolation processing on an input signal of the interpolation filter circuit, and the integrator comb filter is used for carrying out second interpolation processing on the input signal of the interpolation filter circuit; a first interpolation result is obtained and input to the integrator comb filter; and the integrator comb filter is used for performing second interpolation processing on the first interpolation result to obtain a second interpolation result, and taking the second interpolation result as an output signal of the interpolation filter circuit. Therefore, the circuit complexity and the cost can be reduced.

The application discloses a combustion fault alarm method of a gas turbine, and belongs to the technical field of gas turbine fault detection. The method comprises the following steps: obtaining combustion pressure data of the gas turbine; inputting the combustion pressure data of the gas turbine into a pre-constructed pressure feature monitoring model to output a pressure feature monitoring result; inputting the pressure feature monitoring result into a pre-constructed combustion state prediction model, comparing the pressure feature monitoring result with a pre-set health threshold, and outputting a combustion fault result; and generating a fault alarm result according to the combustion fault result; wherein the construction of the pressure feature monitoring model comprises the following steps: obtaining a comb filter; adding an adaptive notch filter after a band-pass filter in the comb filter to obtain the pressure feature monitoring model; and the band-pass filter is an empirical guide multi-band band-pass filter. The application can improve the feature monitoring precision and reliability of the combustion process of the gas turbine, and ensure the stable operation of the combustion system.

The application discloses a heart rate extraction method based on an adaptive comb filter. The method comprises the following steps: 1, obtaining a life signal by processing a radar echo; 2, extracting a breathing rate and other features therefrom, and initializing parameters of the filter; 3, designing an ALE module for evaluating a filtering effect, and initializing parameters of the module; 4, passing the life signal through the adaptive comb filter, and iterating until the parameters to be optimized are basically converged; and 5, selecting a heartbeat frequency from a spectrum of an output signal of the life signal through the filter. The heart rate extraction method based on the adaptive comb filter considers the intermodulation characteristics of breathing and heart rate components of the life signal in a Doppler radar system, and effectively reduces the interference of breathing and higher harmonics on the selection of the heart rate. The experimental results show that when the higher harmonics of breathing in the life signal affect the measurement of the heart rate, the adaptive comb filter can accurately measure the heart rate of a person to be measured.

This invention provides an on-board quantitative diagnostic method for wheel polygons based on frequency response functions, belonging to the field of rail transit technology. This method first utilizes comb filtering to remove the influence of rail roughness, leaving a "purer" wheel polygon response component. Then, it uses the frequency response function to consider and correct the influence of the structure's inherent modes, thereby quantitatively diagnosing the polygon order and roughness level from the axle box vibration signal. This invention solves the problem of wheel and rail roughness vibration components being mixed in the axle box vibration response, leading to misjudgments between the wheel and rail during diagnosis, and the difficulty in quantitatively assessing wheel roughness in on-board wheel polygon detection methods.

The application discloses a power grid voltage sag detection method based on improved discrete Fourier transform and belongs to the field of power quality detection. f (z), a resonator and an adjustment factor G a (z), so as to obtain a phase signal of a positive sequence fundamental component; S3: the module length of the phase signal of the positive sequence fundamental component is calculated, so as to obtain the amplitude of the positive sequence fundamental voltage; after the amplitude is compared with a power grid voltage sag detection threshold, whether the power grid voltage is sagged can be judged. The algorithm can realize accurate detection of the power grid voltage sag event under the non-ideal power grid condition of harmonic distortion and three-phase voltage imbalance.