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56 results about "Frequency interval" patented technology

Frequency | interval |. is that frequency is (uncountable) the rate of occurrence of anything; the relationship between incidence and time period while interval is a distance in space.

A device vibration signal stationary data segmentation method

PendingCN122262506AAlgorithmData mining
The present application relates to a kind of equipment vibration signal stationary data segmentation method, the vibration signal is collected and forms original vibration data, then short-time Fourier transform is carried out to obtain two-dimensional STFT matrix;The effective value of each column data of STFT matrix is calculated respectively to obtain the overall effective value trend of vibration signal;Frequency distribution vector is obtained based on STFT matrix, then the narrow-band frequency interval of the front amplitude ordering is extracted and the effective value trend is calculated;Overall effective value trend of vibration signal and the effective value trend corresponding to all narrow-band frequency intervals are traversed, and candidate split line is determined and marked;The time window position corresponding to candidate split line is mapped as the index value of original vibration data and is sorted;Adjacent index difference in index sequence after sorting is used to determine stationary data interception interval, then original vibration data is interval intercepted to intercept stationary vibration data.The present application can automatically and accurately segment stationary data segment from non-stationary vibration signal, and provide pre-data support for subsequent.
Owner:JIANGSU JINHENG INFORMATION TECH CO LTD

Far-infrared spectrometer and far-infrared spectrometer

This invention provides a far-infrared spectrometer and a far-infrared spectroscopic method that can accurately measure the absorption spectrum derived from a sample. [Solution] In a far-infrared spectrometer 100 comprising a detector 225 that detects light obtained by irradiating a sample with far-infrared light, and a signal processing unit 230 that calculates the absorption spectrum of the sample from the signal from the detector, a first spectrum detected by the detector is obtained when the wavelength of the far-infrared light is changed and irradiated into the measurement optical path with the sample not on the measurement optical path, and a second spectrum detected by the detector is obtained when the wavelength of the far-infrared light is changed and irradiated into the measurement optical path with the sample on the measurement optical path. Then, the difference between the spectral signals is calculated at frequency intervals determined according to the absorption peak due to water vapor, and the frequency of the absorption peak due to water vapor is selected according to a comparison of the difference with a threshold. Based on the selected frequency, data removal is performed on the spectral signal.
Owner:HITACHI HIGH TECH CORP

Bird repelling device with self-recognition function

The invention relates to the technical field of bird repelling devices, in particular to a bird repelling device with a self-recognition function, and the system comprises a target extraction module, a maloperation screening module, a response pause module, an interference classification module and a recognition rule updating module. According to the method, the change combination of multi-channel signals is constructed, time alignment is realized, collaborative features of image brightness edges, audio dominant frequency intervals and infrared heat source distribution are extracted, inconsistent combination contents are identified and screened out, and behavior validity is judged according to interruption and abrupt change signals. Frequently appearing similar disturbances are classified and calibrated, an interference characteristic pattern is formed, edge judgment and a time parameter range are adjusted in combination with identification deviation, a response coordination mechanism among multiple channels is further improved, and the device has dynamic adaptive capacity aiming at different interference modes; the judgment accuracy in the target extraction process and the stability of the expelling response are enhanced, and continuous optimization of recognition and reaction logic in a complex scene is achieved.
Owner:XINGAN ELECTRIC POWER CO OF STATE GRID EAST INNER MONGOLIA ELECTRIC POWER CO LTD +1

Signal parameter estimation device and signal parameter estimation method

PCT designated stageWO2026053446A1Radio wave reradiation/reflectionSignal transitionChirp rate
This signal parameter estimation device is configured to comprise: a candidate value setting unit (1) that sets a plurality of candidate values for a chirp rate representing the ratio of chirp frequency width to chirp time width of a reception signal, which is an observation signal of a chirp signal that is the target for parameter estimation; and a candidate value selection unit (2) that multiplies the reception signal by opposite-phase components of each of the candidate values set by the candidate value setting unit (1), converts the reception signals after the opposite-phase component multiplication to signals of a frequency region, and selects, from among the plurality of candidate values, the candidate value for which an electrical power peak value of the signal of the frequency region is relatively larger. Moreover, the signal parameter estimation device comprises: a frequency width estimation unit (3) that multiplies the reception signal, which is the observation signal, by the opposite-phase component of the candidate value selected by the candidate value selection unit (2), converts the reception signal after the opposite phase component multiplication to a signal of the frequency region, and, on the basis of frequency intervals included in the post-conversion signal of the frequency region which correspond to a plurality of electrical power peak values, estimates the chirp frequency width; and a time width estimation unit (4) that estimates the chirp time width from the chirp frequency width estimated by the frequency width estimation unit (3) and the candidate value selected by the candidate value selection unit (2).
Owner:MITSUBISHI ELECTRIC CORP

Synchronization signal block processing method, device and equipment

Disclosed are a synchronization signal block processing method, apparatus and device, belonging to the field of communications, the synchronization signal block processing method of the embodiment of the present application comprising: a first device detecting a first synchronization signal block (SSB) portion at a first synchronization grid, the first synchronization grid being related to the first SSB portion, and the first equipment processes the second SSB part according to the first SSB part, and the first SSB part and the second SSB part form an SSB. Therefore, the frequency interval of the synchronization grid can be increased, the sending period of the SSB can be increased, and the complexity and time delay of searching on the frequency domain by the first equipment are reduced, so that network energy saving is realized.
Owner:VIVO MOBILE COMM CO LTD

Matching iteration method of sound field model

The invention provides a matching iteration method for a sound field model, and aims to remarkably improve the efficiency and accuracy of simulating and calculating a sound field characteristic rule through systematic model comparison and evaluation. The core thought of the method is that for the complex ocean sound field simulation problem, the limitation of a single model is broken through, and the optimal frequency interval suitable for the ray model with high calculation efficiency is defined by introducing a multi-model comparison verification framework. In the specific implementation process, a ray model with the advantage of calculation speed and a reference model such as a parabolic equation model and a coupling normal wave method which are recognized to be high in precision in a low-frequency band range are subjected to cooperative comparison and iterative verification, and a certain sound source depth, a certain receiving depth and a certain calculation distance are set. Obtaining a comparison result of a parabolic equation model, a coupling normal wave method and a ray model, and comprehensively considering two aspects of calculation speed and calculation precision to obtain the optimal sound source frequency of the ray model for iterative selection.
Owner:JIANGNAN SHIPYARD (GRP) CO LTD

Communication device, method, and non-transitory computer-readable storage medium for calibration

This communication device including a plurality of radio frequency (RF) processing circuits for an antenna array is configured to: transmit first calibration signals having a first subcarrier spacing (SCS) through a plurality of RF transmission paths of the plurality of RF processing circuits; obtain the first calibration signals through a plurality of RF reception paths of the plurality of RF processing circuits; identify a bandwidth of a frequency domain having an amplitude variation of the first calibration signals less than a first threshold value and a phase variation of the first calibration signals less than a second threshold value, on the basis of amplitude information and phase information of the first calibration signals; and perform calibration by transmitting second calibration signals on orthogonal frequency division multiplexing (OFDM) symbols according to a second SCS corresponding to the bandwidth of the frequency domain from among a plurality of SCSs, wherein the second SCS indicates a frequency interval of each of the OFDM symbols, and a time interval of each of the OFDM symbols is inversely proportional to the second SCS.
Owner:SAMSUNG ELECTRONICS CO LTD

A drive fault feedback method and feedback system

The application provides a driving fault feedback method and a feedback system. The method first determines frequency segments corresponding to different fault types; then feedbacks a detected fault level signal for logical processing; evaluates fault priority, changes the fault level signal to a low level according to the priority, changes the low level to a high level after a plurality of counting points, takes the high level as an initial value, and continuously outputs frequency signals corresponding to different fault types; finally collects the frequency signals, counts values between two rising edges, and determines a fault type according to the obtained counting values and the fault type frequency segments. The method uses a single channel to feedback fault information, transfers fault information according to feedback pulse frequency, and different frequency bands represent different faults, so that different fault types can be distinguished. By setting a wide fault frequency band and a frequency interval zone, the influence of interference can be greatly reduced.
Owner:HIWING TECH ACAD OF CASIC

A time domain detection and doppler frequency offset estimation method and device for data link signals

ActiveCN122053319BTime domainReal signal
The application provides a time domain detection and Doppler frequency offset estimation method and device of a data link signal, relates to the technical field of signal processing, and comprises the following steps: in the process of performing a sliding window detection on an entire real signal data, for each window, performing coarse scanning on a target frequency interval to determine a first frequency point with maximum integral power, performing fine scanning on the frequency corresponding to the first frequency point to determine a second frequency point with maximum integral power, taking the frequency corresponding to the second frequency point as a target peak frequency of the window, and taking the integral power at the second frequency point as a target integral power of the window; determining a current adjacent frequency reference power based on the integral power at the adjacent frequency points of the second frequency point; determining whether the window hits based on the target integral power and the current adjacent frequency reference power; determining a best hit window from a plurality of hit windows and performing frequency offset fine estimation to obtain a final frequency offset. The application can realize low-complexity fast frequency offset estimation and reduce the calculation amount and online time delay.
Owner:NEXWISE INTELLIGENCE CHINA LTD

Method for determining structural stress range distribution and related equipment

The invention discloses a method for determining structural stress range distribution and related equipment, which output stable and reliable structural stress range distribution by optimizing a frequency domain discrete and time domain reconstruction mode and combining a multi-round statistical optimization and fusion strategy. The method comprises the following steps: acquiring a stress power spectrum of a target structure, randomly dividing frequency intervals in a preset frequency band and distributing phases to obtain a discrete spectrum; reconstructing a time domain stress time calendar and carrying out rain flow counting, and generating multiple groups of dimensionless rain flow stress range probability density distributions; and after average fairing and moment keeping correction, candidate sub-distribution is generated by adopting a multi-fairing strategy, and final distribution is obtained by combining evaluation index weighted fusion. According to the method, the time calendar authenticity is improved through random discretization, distribution convergence is realized through multi-time statistical fusion, and smoothness and statistical characteristics are taken into account through moment maintenance and multi-strategy fusion. Only stress power spectrum input is needed, the method is suitable for complex scenes such as broadband and multi-peak spectrum, the method can be embedded into an existing system for automatic operation, analysis cost is reduced, and fatigue evaluation precision is improved.
Owner:HONG KONG UNIV OF SCI & TECH (GUANGZHOU) +1

Operation state monitoring method and system based on intelligent water pump

The invention discloses an operation state monitoring method and system based on an intelligent water pump, and relates to the technical field of water pump monitoring, and the method comprises the steps: obtaining the basic working condition parameters of the current operation of the water pump, and calculating the theoretical resonant frequency interval of a sealing cavity system based on the parameters and the inherent characteristics of the water pump; a target frequency scanning sequence is generated, the sequence is used for sequentially adjusting the rotating speed or flow of the water pump to a set of discrete steady-state values, and the system excitation main frequency corresponding to each steady-state value is included in the theoretical resonant frequency interval; according to the invention, dependence on macroscopic leakage signals is broken through, early micro-leakage is identified by using the characteristic distribution rule of resonance energy, the detection sensitivity is significantly improved, and early warning can be given in time at the initial stage of leakage.
Owner:TAIZHOU SHIFENG MECHANICAL & ELECTRICAL EQUIP CO LTD

Distance measurement method based on two adjacent frequency detection phases

PendingCN121784713AImprove ranging accuracyGood ranging accuracyElectromagnetic wave reradiationComputational physicsFrequency detection
In order to solve the problems that a circuit structure is simple, and distance measurement with good accuracy and precision can be achieved, the invention provides a method which does not need to adopt an array antenna, does not need to measure time difference, and only measures phases of two pilot frequency signals to achieve ambiguity-free and high-precision distance measurement. Different from the existing mode of solving the distance by measuring the phase difference, the new method directly uses a distance measurement equation for measuring the phase. In order to eliminate phase ambiguity, the frequency interval of two different-frequency signals is limited to ensure that the same wavelength integer cycle number exists during different-frequency phase detection on the detected distance length. On the basis, the wavelength whole cycle number can be solved through joint solution of a double-frequency phase ranging equation set. And then the detection distance can be obtained by using the phase distance measurement equation again. Simulation analysis shows that in a distance range without phase shift ambiguity, the double-frequency phase distance measurement method is not only good in accuracy, but also capable of obtaining distance measurement precision smaller than 0.2%.
Owner:SHANGHAI YUTAO INTELLIGENT TECH CO LTD +1

Method for trace detection of leaks in gas path systems by photoacoustic spectroscopy and related devices

The present application relates to the technical field of gas leakage detection, in particular to a photoacoustic spectroscopy trace detection method for gas path system leakage and related device. The photoacoustic spectroscopy trace detection method for gas path system leakage comprises the following steps: emitting specific wavelength laser with double-frequency intensity modulation to the suspected leakage area of the gas path system, the specific wavelength matches two adjacent absorption spectral lines of the target leakage gas, and the frequency difference of the double-frequency intensity modulation corresponds to the frequency interval of the two adjacent absorption spectral lines, so that the leakage gas molecules absorb laser energy of two frequencies at the same time to enhance the amplitude of the periodic photoacoustic signal. Through the cooperation of multiple technical links, the present application effectively solves the problems of weak trace signal, difficult noise suppression and low positioning accuracy in the existing method, and realizes the unification of high-sensitivity trace detection and centimeter-level accurate positioning for gas path system leakage.
Owner:SHANGHAI YUEZHI SEMICONDUCTOR TECHNOLOGY CO LTD

Nano-film thickness measurement method based on terahertz sub-wavelength interference enhancement

The invention discloses a nano-film thickness measurement method based on terahertz sub-wavelength interference enhancement. The method comprises the following steps: S1, acquiring a terahertz time domain signal of a to-be-measured sample formed by a film / substrate in a reflection or transmission mode; s2, performing frequency domain transformation on the time domain signal to obtain an amplitude spectrum of the time domain signal; s3, extracting a characteristic frequency interval of a periodic oscillation signal generated by multi-beam interference in the thin film; and S4, based on the characteristic frequency interval and the refractive index n of the thin film material, calculating to obtain the physical thickness d of the thin film. According to the nano-film thickness measurement method based on terahertz sub-wavelength interference enhancement, the multi-beam interference effect generated by terahertz waves reflected or transmitted by the upper interface and the lower interface of an ultrathin film is utilized, tiny thickness information is converted into periodic interference fringes easy to observe in the frequency domain, and accurate inversion of the sub-wavelength thickness is achieved.
Owner:SHAOXING RES INST OF ZHEJIANG UNIV

A device and method for detecting instantaneous broadband and phase-modulated light source signals.

This invention discloses a detection device and method for instantaneous broadband and phase-modulated light source signals, belonging to the field of laser signal processing. The detection device includes a polarization-maintaining transmission fiber, a waveguide-type amplitude modulator, a high-speed photodetector, and a signal frequency detector. The detection device provided by this invention features an all-fiber structure, resulting in efficient and accurate detection. It simplifies the performance requirements for the signal generator and facilitates demodulation of the frequency-interval periodic signal carried by the phase-modulated pulse, exhibiting high overall reliability. Furthermore, it can beat the signals of the two branches simultaneously, reducing the bandwidth requirements of the photodetector and avoiding integration of the time-domain signal. This allows for direct differentiation of whether the injected signal is broadband or single-frequency in a specific time slice using ordinary photodetector methods. The invention also provides a calculation process and judgment criteria for analyzing and identifying light source signals. After obtaining the modulation parameters of the injected light source signal, it can automatically and quickly determine whether the signal is an instantaneous broadband light source signal or a phase-modulated light source signal, achieving automatic analysis and judgment of the signal category throughout the entire process.
Owner:LASER FUSION RES CENT CHINA ACAD OF ENG PHYSICS

Method and apparatus for adaptive cutoff frequency filtering under unsprung control

This invention provides an adaptive cutoff frequency filtering method and apparatus for unsprung control, belonging to the field of automotive control technology. The method includes: determining a cutoff frequency based on the wheel's rotational fundamental frequency, the dominant frequency of vibration generated by road excitation, and the wheel's resonant frequency; establishing an initial upper cutoff frequency and a lower cutoff frequency; constructing a noise monitoring frequency band based on the cutoff frequency and preset pure noise setting frequency intervals and noise bandwidth; calculating the actual signal quality based on the theoretical target signal quality; determining the measurement deviation of the signal quality based on the cutoff frequency, the theoretical target signal quality, the total discretized signal power within the noise monitoring frequency band, the total discretized noise power within the noise monitoring frequency band, and the smoothing time constant; and determining the target upper cutoff frequency based on the measurement deviation, the theoretical target signal quality, and the actual signal quality, and performing cutoff frequency filtering based on the target upper and lower cutoff frequencies. This invention can solve the problem of poor consistency gains in unsprung control.
Owner:WUHAN JIANGXIA CHUNENG AUTOMOBILE TECHNOLOGY R&D CO LTD

An angle measurement method based on frequency diversity technology

PendingCN122386259ARadar antennasNoise
The application relates to an angle measurement method based on frequency diversity technology. The method comprises the following steps: obtaining a frequency interval constraint set according to the height of a radar antenna, the distance between a target and the radar and the flight height of the target; selecting a frequency interval according to the frequency interval constraint set, and determining the number of frequency points according to the frequency interval and the total width of the system; the radar transmits signals of each frequency point in turn in a time division mode, and receives target echo signals of each frequency point; calculating the target pitch monopulse ratio according to the target echo signals, and calculating a target pitch angle measurement value vector of all frequency points according to the target pitch monopulse ratio; calculating the target noise variance of each frequency point according to the real-time signal-to-noise ratio, and obtaining the target noise covariance matrix of all frequency points according to the target noise variance of each frequency point; and calculating the target sample residual of each frequency point. The application introduces the frequency diversity technology, thereby suppressing random and systematic errors caused by multipath, and significantly improving the tracking accuracy of the radar.
Owner:XIAN HUANGHE MECHANICAL & ELECTRICAL CO LTD

User health data intelligent acquisition system based on fitness equipment

The invention belongs to the technical field of user health data intelligent acquisition, and provides a user health data intelligent acquisition system based on fitness equipment, comprising: a coincidence frequency interval identification module, based on time-frequency analysis of a mixed signal, positioning a coincidence interval of stride frequency and heart rate; the coupling model construction module distinguishes a linear / nonlinear coupling relationship through Pearson correlation analysis, and constructs a fitting model in a partitioning manner; an analysis curve generation module generates a time-heart rate associated analysis curve in combination with the model when the stride frequency enters the coincidence interval; the interference elimination module divides four types of feature combinations through trend continuity and physiological rationality analysis after stride frequency is separated from a coincidence interval, and stride frequency interference is eliminated by adopting deviation correction, smooth interpolation, model prediction and trend calibration modes in a targeted manner; the problem of data distortion caused by motion artifacts is effectively solved, and the accuracy and reliability of heart rate collection of the fitness equipment are improved.
Owner:ZHONGKE YUNDONG (ZHEJIANG) DIGITAL INTELLIGENCE TECHNOLOGY CO LTD

A Time-Frequency Analysis Method for Power Faults Based on Synchronous Extraction Transformation

This invention relates to the field of power system fault signal processing, specifically to a power fault time-frequency analysis method based on synchronization extraction transform. The invention employs a Rogowski coil sensing system to acquire transient fault signals, obtains an initial time-frequency representation through short-time Fourier transform, and derives a corrected time-frequency representation using the derivative of a window function. Based on the ratio of the two representations, the instantaneous frequency trajectory is calculated. A synchronization extraction operator is constructed using a binarization criterion with discrete frequency intervals as an adaptive threshold. Only time-frequency coefficients on the instantaneous frequency trajectory are retained, rather than all coefficients in the concentrated energy diffusion region, resulting in a highly concentrated energy time-frequency representation. This method significantly improves time-frequency resolution while exhibiting stronger noise robustness and multi-component signal separation capabilities, providing an effective technical means for rapid and accurate fault location in distribution networks.
Owner:STATE GRID JIANGXI ELECTRIC POWER CO LTD RES INST

Self-adaptive multiple joint diversity method, system and device based on evaporation waveguide channel and medium

PendingCN121770651AMake smart choicesImprove reliabilityScatter propogation systemsTransmission monitoringAcousticsCoherence bandwidth
The invention relates to the technical field of communication, in particular to a self-adaptive multi-joint diversity method, system and equipment based on an evaporation waveguide channel and a medium. Meteorological parameters are collected, system diversity parameters are defined, a corrected refractive index profile is constructed, and the height of an evaporation waveguide is determined; based on the corrected refractive index profile, an initial field is calculated through a primary algorithm, the generated initial field is placed in a constructed refractive index profile environment, propagation and output field intensity distribution of an electromagnetic field in a non-uniform medium are solved step by step, RMS time delay spread is calculated through a secondary algorithm, coherent bandwidth is estimated, and the minimum frequency interval is determined based on the coherent bandwidth. Adjusting the minimum frequency interval; the method comprises the following steps: comparing a frequency interval with a minimum frequency interval, adaptively adjusting the frequency interval, respectively simulating space diversity, time diversity and frequency diversity, superposing different diversity, calculating outage probability and fading depth under different diversity, reducing depth fading caused by severe fluctuation of signal amplitude, and improving system availability.
Owner:HAINAN POWER GRID CO LTD

Music visualisation method, apparatus, computer readable storage medium and vehicle

The application discloses a music visualization method and device, a computer readable storage medium and a vehicle, wherein the method comprises: acquiring at least one frequency corresponding to an audio signal within a preset time before a current time; determining a frequency interval in which each frequency is located, and determining an amplitude corresponding to the frequency interval to obtain an amplitude corresponding to each frequency; wherein the frequency interval comprises a plurality of frequency intervals, each frequency interval has a corresponding amplitude; and controlling an atmosphere lamp according to each frequency and the amplitude corresponding to each frequency. Thus, the linkage between the atmosphere lamp and music can be realized, and different frequency characteristics of the vehicle-mounted music can be exhibited by controlling the atmosphere lamp, so that the visual presentation effect of the vehicle-mounted music is better, a more cool music atmosphere is created, and the user experience is improved.
Owner:ZHEJIANG ZEEKR INTELLIGENT TECH CO LTD +1

Optical microcavity dispersion measurement method based on dispersion line type real-time calibration

The invention provides an optical microcavity dispersion measurement method based on dispersion linetype real-time calibration, which is applied to the technical field of microcavity dispersion measurement, and comprises the following steps: converting the position extraction of an optical sideband into the position extraction of a dispersion linetype, and demodulating the optical sideband through a frequency mixer to obtain a sideband harmonic peak of a specific dispersion linetype; adjusting the phase difference between a modulation signal and a demodulation signal of the high-stability radio frequency source, identifying the position of a dispersion line type sideband harmonic peak, and extracting the frequency interval of the sideband harmonic peaks on the two sides of each resonance mode; dynamically calibrating the optical fiber Mach-Zehnder interferometer based on the number of sinusoidal signal cycles in the frequency interval of the dispersion line type sideband resonance peaks on the two sides of each resonance mode to obtain a calibrated Mach-Zehnder interferometer; and generating a dispersion measurement result of the optical microcavity according to the calibrated Mach-Zehnder interferometer interference signal. According to the invention, the dispersion measurement precision and the automation level can be improved.
Owner:NATIONAL INSTITUTE OF METROLOGY CHINA

Method and apparatus for estimating global navigation satellite system satellite inter-frequency clock bias

The embodiment of the application provides a global navigation satellite system satellite frequency interval clock bias estimation method and device, the method comprises: calculating the observation data of each satellite collected by a plurality of observation stations in a specified time period to generate a harmonic function coefficient table; if the arc length of the current data arc segment is greater than or equal to the set length threshold, the corresponding first coefficient group is matched according to the harmonic function coefficient table, and the first coefficient group is determined as the initial value of the fitting coefficient group; the least square fitting is carried out on the current data arc segment through the initial value of the fitting coefficient group, and the satellite frequency interval clock bias fitting value of the current data arc segment is obtained, so as to eliminate the error of positioning calculation; the arc length to be processed is not required, the data amount is reduced, and the timeliness of fitting processing is improved.
Owner:BEIJING AEROSPACE CONTROL CENT

Motor abnormal sound defect detection method and device based on target detection and storage medium

The invention relates to the field of motor quality detection, and provides a motor abnormal sound defect detection method and device based on target detection and a storage medium. The method comprises the following steps: acquiring an original audio signal of a to-be-detected motor, and generating a normalized time-frequency image highlighting potential defect characteristics based on a reference sound spectrum; inputting the normalized time-frequency image into a pre-trained target detection neural network model, and outputting bounding box coordinates and category confidence of the candidate defect area in the time-frequency image; all candidate defect areas are screened by applying a non-maximum suppression algorithm based on an adaptive threshold value, redundant frames with high overlapping degree and low confidence coefficient are removed, and a final defect feature area is reserved; and judging whether a defect feature region reserved after screening by a non-maximum suppression algorithm exists or not, if so, judging that the to-be-detected motor is unqualified, and analyzing and outputting a time interval, a frequency interval and confidence information associated with the defect based on a bounding box coordinate of the defect feature region.
Owner:SHENZHEN BORUICHUANG TECH CO LTD

A bearing damage positioning method based on acoustic emission signal lamb wave dispersion mode matching

ActiveCN117147159BHelps in remaining life predictionCarry out remaining life predictionMachine part testingSustainable transportationCorrelation coefficientAcoustic emission
The application relates to a bearing damage positioning method based on Lamb wave dispersion mode matching of acoustic emission signals, wherein different frequency band components of original acoustic emission signals with the same frequency interval are obtained; a time of arrival curve is obtained; a theoretical dispersion curve of Lamb wave propagation in a bearing is solved, then a coordinate system is unified with the signal time of arrival curve; the dispersion curve and the time curve are matched through a Pearson correlation coefficient index; a formula is established according to a speed difference and a time difference, and a bearing damage distance is calculated; the sensor is moved by a certain distance to be measured again, and the damage position is determined through the two results. The method of matching the Lamb wave propagation mode can determine the propagation speed of the acoustic emission signals with different frequencies, the accuracy of the time difference positioning method is greatly improved, the bearing damage position can be directly found through a single sensor, the bearing fault diagnosis can be realized without depending on the bearing rotating speed, the installation difficulty can be effectively reduced, and the detection cost can be reduced.
Owner:KUNMING UNIV OF SCI & TECH

Second-order IIR filter and optimization method thereof

PendingCN121508493ADigital technique networkIir filteringFilter system
The invention provides a second-order IIR (Infinite Impulse Response) filter and an optimization method thereof. The optimization method comprises the following steps: for a target cut-off frequency fc, setting a target cut-off frequency interval as [fcmin, fcmax], and setting a frequency interval delta f; generating a list formed by a plurality of candidate target cut-off frequencies in the target cut-off frequency interval by taking a frequency interval delta f as a step length, wherein the ith candidate target cut-off frequency is fc (i) = fcmin + i * delta f; calculating a filter system corresponding to each candidate target cut-off frequency, quantizing a filter coefficient corresponding to each candidate target cut-off frequency to obtain a quantized filter coefficient, and calculating a quantization error of a second-order IIR filter based on the quantized filter coefficient; and selecting the candidate target cut-off frequency with the minimum quantization error as the actual target cut-off frequency, and using the quantized filter coefficient corresponding to the actual target cut-off frequency as the filter coefficient of the second-order IIR filter. In this way, the quantization error of the whole system is reduced by optimizing the quantization process of the filter coefficient.
Owner:MEMSIC SEMICON WUXI

Optical coherence tomography method and system based on multi-dimensional dynamic feature fusion

The invention discloses an optical coherence tomography method and system based on multi-dimensional dynamic feature fusion, and relates to the technical field of optical coherence tomography, and the method comprises the steps: S1, obtaining continuous interference signals of OCT scanning; s2, performing preprocessing and fast Fourier transform to generate an intensity signal; s3, carrying out logarithmic domain transformation on the intensity signal and calculating a variance to obtain an LIV value and mapping the LIV value into a pseudo-color image based on the LIV value; s4, performing singular value decomposition on the intensity signal, calculating the power spectral density and dividing a frequency interval; reconstructing to obtain a reconstructed signal and mapping the reconstructed signal into a pseudo-color image based on frequency distribution; s5, calculating an autocorrelation function of the intensity signal to obtain an attenuation curve, performing function fitting to obtain an OCDS value, and mapping the OCDS value into an image based on attenuation characteristics; and S6, fusing the three images into an HSV color space. According to the method, the LIV algorithm, the SVD-PSD algorithm and the improved OCDS algorithm are combined, conjoint analysis is carried out on the OCT signals in the time domain, the frequency domain and the related domain, and comprehensive visual display is carried out in the HSV color space.
Owner:XIANG AN BIOMEDICINE LABORATORY +1

Active sonar processing method and system based on COSTAS waveform

This invention discloses an active sonar processing method and system based on the COSTAS waveform. It generates the COSTAS waveform signal by adjusting the frequency interval and the number of frequency jumps; performs frequency-domain beamforming based on steering vectors and Fast Fourier Transform, improving the signal-to-noise ratio (SNR) of the received signal and increasing azimuth information; achieves normalized matched filtering by selecting the maximum frequency modulus and estimating noise; and obtains the azimuth history map through approximate coherent weighted fusion. This invention effectively overcomes channel frequency-selective fading and significantly improves signal detection performance. Furthermore, by fully utilizing the coherent components in each frequency and combining them with an SNR-weighted fusion method, it effectively improves the echo gain in the azimuth history map, enhancing the accuracy and reliability of detection.
Owner:HUNAN UNIV

A dynamic power quality disturbance signal detection method, device and medium

ActiveCN121347949BImplement adaptive resolution adaptationOvercoming difficult-to-balance limitationsElectrical testingTime–frequency analysisVariable resolution
The application discloses a dynamic power quality disturbance signal detection method, device and medium, and the method steps comprise the following steps: S01, acquiring a dynamic power quality disturbance signal to be detected; S02, dividing a signal frequency band, and performing time-frequency analysis on the dynamic power quality disturbance signal by using an improved variable resolution S transform method; the improved variable resolution S transform method is an S transform based on a Gaussian window, and a Gaussian window scale factor is used to optimize the Gaussian window function; S03, performing a synchronous squeezing rearrangement operation on the improved variable resolution S transform result, so that energy components scattered in adjacent frequency intervals are aggregated to real frequency axis positions, and a time-frequency matrix after synchronous squeezing rearrangement is obtained; and S04, detecting signal components of the time-frequency matrix after synchronous squeezing rearrangement. The application can reduce energy diffusion and realize high-precision detection of non-stationary multi-scale complex dynamic power quality disturbance signals.
Owner:湖南工商大学