Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

46 results about "Spectral amplitude" patented technology

Power is proportional to the square of amplitude, so squaring the amplitude spectral density gives you a power spectral density, or how much power is in each frequency.

Bridge health monitoring method and system based on artificial intelligence

The invention discloses a bridge health monitoring method and system based on artificial intelligence, and relates to the technical field of bridge monitoring, and the method comprises the steps: building a bridge finite element physical model based on a bridge geometric model; and performing modal analysis and strain energy analysis based on a finite element physical model, determining key nodes based on an analysis result to generate sensor candidate nodes, and optimizing the sensor layout by using a genetic algorithm. According to the method, on the basis of bridge design parameters, a finite element analysis model is used for building a physical model for a bridge, sensitive areas in the bridge are converted into key monitoring nodes according to modal analysis and strain energy analysis, and sensor layout is optimized according to the key monitoring nodes in combination with a genetic algorithm, so that high-quality data acquisition is achieved; the monitoring efficiency is maximized, the cost is reduced, and dynamic damage characteristic indexes in the bridge are comprehensively extracted by calculating parameters such as the frequency spectrum amplitude, the damping ratio and the strain energy change.
Owner:LANZHOU JIAOTONG UNIV

Adaptive threshold SAMP reconstruction method for power quality disturbance signal

The invention discloses a self-adaptive threshold SAMP reconstruction method for a power quality disturbance signal. According to the method, a compression observation value is obtained by constructing a random Gaussian observation matrix, and sparse representation is carried out on an original signal by using discrete Fourier transform. In the iterative reconstruction process, the spectrum amplitude difference is introduced for the first time to serve as an adaptive termination basis, and automatic adaptation of different noise levels and different disturbance characteristics is achieved in combination with a dynamic threshold update function. According to the method, the problems of traditional SAMP sparseness overestimation and redundant iteration are effectively avoided, and the calculation load is remarkably reduced. Compared with an OMP method, an original SAMP method and the like, the method has the advantages that the number of iterations can be reduced by 30%-60%, the reconstruction signal-to-noise ratio is increased by 2-5 dB, the root-mean-square error is reduced by 10%-25%, higher robustness and real-time performance are achieved in power quality disturbance signal reconstruction, and the method is quite suitable for scenes such as compressed sampling, edge calculation and high-speed signal reconstruction in a power quality monitoring system.
Owner:HUNAN NORMAL UNIVERSITY

Measurement equipment and frequency estimation method and denoising method for equipment noise in measurement equipment

The invention relates to the technical field of photoacoustic measurement, and particularly provides measuring equipment and a frequency estimation method and a denoising method of equipment noise therein, the frequency estimation method comprises the following steps: controlling pump light and probe light to irradiate a first sample to be measured, the pump light generating ultrasonic waves on the surface of the first sample to be measured, the detection light is reflected by the surface of the first to-be-detected sample to form first detection signal light; acquiring a first photoacoustic time domain signal formed by the first detection signal light; removing a non-noise signal and a random noise signal in the first photoacoustic time domain signal to obtain a first time domain noise signal; performing time-frequency transformation on the first time-domain noise signal to obtain a first noise spectrum; and determining the frequency of the equipment noise according to the spectrum amplitude of the first noise spectrum. Thus, the device noise in the photoacoustic signal can be removed in a targeted manner according to the frequency of the device noise subsequently, and compared with a traditional overall noise removal manner, the signal-to-noise ratio and the measurement sensitivity can be improved.
Owner:SKYVERSE TECH CO LTD

Infrared image super-resolution method based on conditional diffusion model

PendingCN121921178AImage enhancementImage analysisImage resolutionSpectral amplitude
The invention provides an infrared image super-resolution method based on a conditional diffusion model, and belongs to the technical field of infrared image super-resolution reconstruction. The method comprises the following steps: adding noise to a high-resolution infrared image to construct a diffusion process; splicing the noisy image, the low-resolution infrared image and the visible light image in a channel dimension, and inputting the spliced image into a U-Net encoder to extract multi-scale fusion features; the decoder recovers the spatial resolution through layer-by-layer up-sampling in combination with jump connection, and meanwhile, structural features of a low-resolution image and texture features of a visible light image are introduced into each layer to carry out spatial condition modulation, so that cross-modal stable guidance is realized; and constructing a joint objective function including denoising loss, frequency domain phase consistency loss and spectrum amplitude constraint loss, and optimizing network parameters through back propagation. According to the method, complementary information of infrared and visible light images can be fully fused, and the problems of insufficient detail recovery and artifact generation of an existing method are effectively solved.
Owner:KUNMING UNIV OF SCI & TECH

Fabric texture fidelity rendering method and system based on scanned image and target color number

The invention discloses a fabric texture fidelity rendering method and system based on a scanned image and a target color number, and solves the technical problems of poor color perception consistency and texture detail loss. The method comprises the steps of preprocessing a standardized input image through illumination compensation, performing double-space color mapping in an LAB color space, partitioning the image by adopting K-means clustering according to texture features of a gray-level co-occurrence matrix, establishing a color mapping function containing global mapping transformation and local adaptive adjustment, and adaptively determining a fusion coefficient according to regional variance; decomposing the image into a base layer and a detail layer by adopting guide filtering, and performing spectrum constraint on the detail layer to ensure that the spectrum amplitude is consistent with the original; extracting material parameters such as a normal map, a roughness map and a metallity map; according to the method, fabric texture details are completely reserved while color perception consistency is guaranteed, rendering reality is improved, batch processing of multiple groups of target color numbers is supported, and the method is suitable for application scenes such as costume design, e-commerce display and virtual fitting.
Owner:MAYTEX (SUZHOU) TECHNOLOGY CO LTD

Construction method and use of deep learning-based denoising model

A construction method of a deep learning-based pipeline leakage detection and denoising model: performing signal modulation on clean signals and noise signals in different proportions to obtain noisy signals; performing short-time Fourier transform (STFT) on the clean signals to extract spectral amplitudes of the clean signals, and using absolute values of the spectral amplitudes of the clean signals as target samples; performing STFT on the noisy signals to obtain spectral amplitudes of the noisy signals, calculating absolute values of the spectral amplitudes of the noisy signals, correcting the absolute values of the spectral amplitudes of the noisy signals, and using the corrected spectral amplitudes as training samples; normalizing amplitudes of the training samples and the target samples, and then inputting the amplitudes into a denoising convolutional encoding-decoding neural network for training; and optimizing the trained denoising convolutional encoding-decoding neural network to obtain a pipeline leakage detection and denoising model.
Owner:INNOVATION CENTER OF YANGTZE RIVER DELTA ZHEJIANG UNIVERSITY +1

Optical metrology system and method

A measurement system for use in optical metrology, the measurement system which includes a control system configured and operable to carry out the following: (i) receive raw measured data generated by a measurement unit that is configured and operable for performing normal-incidence spectral interferometric measurements on a sample and generating the raw measured data indicative of spectral interferometric signals measured on the sample for a number of different optical path differences (OPDs) between sample and reference arms using infrared wavelengths; (ii) extract, from the raw measured data, a portion of spectral interferometric signals describing variation of signal intensity with a change of an optical path difference OPD during interferometric measurements, said portion of the spectral interferometric signals being independent of interferometric signals returned from a bottom portion of the sample in response to said illuminating electromagnetic field; and (iii) directly determine, from the extracted portion of the spectral interferometric signals, both spectral amplitude and phase of reflection of the illuminating electromagnetic field from the top portion of the sample, thereby enabling to determine a measured spectral signature characterizing the top portion of the sample.
Owner:NOVA MEASURING INSTR LTD

Distortion-resistant distributed optical fiber sensing method and system based on array phase spectrum demodulation

The invention belongs to the technical field of distributed optical fiber sensing, and relates to an anti-distortion distributed optical fiber sensing method and system based on array phase spectrum demodulation, an ultra-weak reflection optical fiber Bragg grating array is used as a sensing optical fiber, a series of reflection peaks with the signal-to-noise ratio higher than that of RBS are generated, a reflection peak sequence is formed, and the beat frequency signal spectrum amplitude is increased. A discrete beat frequency signal with frequency domain distortion output by an OFDR sensing system is converted to a frequency domain through Fourier transform of a symmetric window function to obtain a corresponding discrete frequency spectrum, and characteristic parameters such as amplitude and phase of a reflection peak sequence in the frequency spectrum are tracked and extracted; and then frequency correction factors of the reflection peak sequence in all measurement periods are calculated by using an amplitude interpolation correction method to obtain a corrected accurate array phase spectrum, and phase difference and strain calculation are performed to realize multi-point quasi-distributed strain demodulation for suppressing frequency domain distortion such as Doppler frequency shift and the like. The frequency resolution limitation caused by the fence effect is broken, and the fidelity of the frequency domain distortion signal is recovered.
Owner:BEIJING INST OF TECH

Real-time speech enhancement method and system based on dual-stage spectral subtraction and dual-mask fusion

The invention provides a real-time speech enhancement method and system based on dual-stage spectral subtraction and dual-mask fusion, and relates to the technical field of speech signal processing, and the method comprises the steps: respectively carrying out the framing, windowing and short-time Fourier transform of a left channel mixed signal and a right channel noise reference signal, obtaining a complex frequency spectrum and an amplitude spectrum of the left channel signal and an amplitude spectrum of the right channel noise reference signal; and performing noise estimation by adopting a first noise multiplication factor based on the amplitude spectrum of the right channel noise reference signal to obtain a noise estimation spectrum, and performing constraint spectrum subtraction on the amplitude spectrum of the left channel signal to obtain voice amplitude estimation of a first stage. According to the method, effective suppression of TTS noise and real-time speech enhancement are realized through framing windowing and frequency domain conversion in combination with over-estimation spectrum subtraction and double-mask fusion through two-stage gain application and time domain reconstruction.
Owner:BEIJING ZHIZI NEW STAR TECHNOLOGY CO LTD

Method for monitoring wear state of piston ring of vehicle diesel engine, storage medium and device

The application discloses a kind of vehicle diesel engine piston ring wear state monitoring method, storage medium and device, it is related to diesel engine state monitoring field, the method includes defining the measured point sensitivity characteristic value for representing the attenuation amount of measured point energy relative to acoustic emission source energy, and determining multiple acoustic emission source positions and measured point positions for installing acoustic emission sensor on cylinder cover;Drive acoustic emission sensor at acoustic emission source to produce excitation, the measured point sensitivity characteristic value between each measured point and acoustic emission source is calculated, determine the measured point for carrying out fault identification among all measured points, as detection measured point;Acoustic emission signal of detection measured point is obtained when piston is located in set position during diesel engine operation, the PSD spectral amplitude of acoustic emission signal is calculated, and compared with the fault threshold under different fault states of piston ring, realize piston ring fault determination.The application can realize the accuracy and effectiveness of piston ring fault diagnosis.
Owner:DONGFENG COMML VEHICLE CO LTD

An Adaptive Background Noise Detection Method, System and Medium

The present invention provides an adaptive background noise detection method, comprising: S1, obtaining a sound signal within a background noise detection interval; S2, performing a fast Fourier transform on each frame of the sound signal to estimate the spectral amplitude of the sound signal; S3, performing a steady-state statistical analysis on the spectral amplitude of the sound signal to calculate the change in the spectral amplitude of the sound signal; S4, performing a dynamic statistical analysis on the spectral amplitude of the sound signal to calculate the change in the spectral variance of the spectral amplitude of the sound signal; S5, determining whether the sound signal is background noise according to the change in the spectral amplitude of the sound signal and the change in the spectral variance of the spectral amplitude of the sound signal. The present invention discriminates whether it is background noise through the spectral signal characteristics of the sound signal, can make timely adjustments according to the changes in the detected environmental noise, and has a high detection accuracy.
Owner:ジャン州立達信光電子科技有限公司

Quantification method and device for moire patterns of screen shot image and storage medium

ActiveCN121860870AHigh compensation accuracyImage enhancementImage analysisVisual perceptionSpectral amplitude
The invention discloses a screen shooting image moire quantification method and device and a storage medium, which are used for improving the compensation precision of a display screen. Acquiring a sub-pixel unit image of the display screen to be tested; performing brightness compensation processing on the sub-pixel unit image to generate an expected brightness compensation image; generating a compensation graph frequency spectrum amplitude image according to the brightness compensation image; generating a stripe frequency band sensing image according to the visual distance and the pixel pitch corresponding to the target color channel; carrying out region division on the frequency spectrum amplitude image of the compensation graph; standard deviations of the elliptical region and the plurality of elliptical ring regions are calculated, and a region standard deviation set is generated; filling a blank image with the standard deviation in the regional standard deviation set to generate a first elliptical ring standard deviation image; performing frequency domain filtering on the first elliptical ring standard deviation image by using the stripe frequency band sensing image to generate a first frequency domain filtering image; and generating a first moire quantization value corresponding to the brightness compensation image according to the compensation image frequency spectrum amplitude image and the first frequency domain filtering image.
Owner:SHENZHEN SEICHITECH TECHN CO LTD

Insulator defect evaluation method based on vibration acoustics

The invention relates to the technical field of intelligent sensors, in particular to an insulator defect evaluation method based on vibration acoustics, and the method comprises the steps: analyzing the amplitude difference between each non-backbone component and an acoustic signal, and the discrete degree of all amplitudes in each non-backbone component, determining the noise influence degree according to the number difference between all the non-backbone components and all the backbone components; determining a signal characteristic value based on the proportion of the average frequency spectrum amplitude of each backbone component in the average frequency spectrum amplitude of the acoustic signal and the random fluctuation degree of all the amplitudes in each backbone component, and determining the disturbance degree in combination with the sound influence degree; and based on the confusion degree and the disturbance degree of the acoustic signal, denoising the acoustic signal by adopting a wavelet function so as to evaluate the defect of the insulator. According to the invention, through adaptive denoising, environmental noise interference is suppressed, and the accuracy and reliability of insulator defect evaluation are improved.
Owner:NANYANG POWER SUPPLY COMPANY OF STATE GRID HENAN ELECTRIC POWER +1

Frequency estimation method for judging interpolation direction based on phase difference

The invention discloses a frequency estimation method for judging an interpolation direction based on a phase difference, which belongs to the technical field of radar signal processing and comprises the following steps of: performing FFT (Fast Fourier Transform) on an original signal of an LFMCW (Linear Frequency Modulated Continuous Wave) radar transmitting signal, finding out positions of a maximum value and a second maximum value corresponding to a frequency spectrum amplitude, solving a phase at a spectral line, comparing the phase difference and judging the interpolation direction. According to the method, the Rife algorithm is improved, interpolation direction judgment is carried out through the phase difference between the maximum spectral line and the second maximum spectral lines adjacent to the two sides, better anti-noise performance is achieved, relatively high stability is achieved, and the problem of interpolation direction misjudgment is avoided.
Owner:SHANDONG ACAD OF SCI INST OF AUTOMATION

Multifunctional audio processing method, device and system

The invention discloses a multifunctional audio processing method, device and system, and relates to the technical field of audio processing, and the method comprises the steps: calculating spectrum amplitude data from a spectrogram of an audio signal; selecting an audio processing function needing to be executed, and outputting control signals and instructions required by each module for realizing the audio processing function; inputting the audio signal or the spectrum amplitude data into a neural network accelerator, and transmitting the weight and bias parameters of a pre-trained neural network model corresponding to the audio processing function to a multiply-accumulate array and each storage module in the neural network accelerator; and decomposing, equivalently and optimizing various operators in the neural network model according to the instruction, so that the various operators are converted into calculations which can be executed by the neural network accelerator, and then the various executable operators are utilized to calculate the audio signal or the spectrum amplitude data according to the weight and the bias parameter to obtain a processing result of the audio processing function. The audio processing efficiency can be improved.
Owner:SUN YAT SEN UNIV

Gas leakage detection method and system based on laser speckle imaging

The invention discloses a gas leakage detection method and system based on laser speckle imaging, and the method comprises the steps: irradiating the outer wall surface of a to-be-monitored region with laser beam expansion to form laser speckles, and continuously collecting a plurality of monitoring speckle images of the to-be-monitored region; segmenting the monitored speckle image and the corresponding original speckle image without leakage into a plurality of sub-windows, and calculating the frequency spectrum amplitude and the frequency spectrum phase of each sub-window; calculating a correlation coefficient between the two sub-windows according to the spectrum amplitudes and the spectrum phases of the sub-windows corresponding to the original speckle image and the monitoring speckle image; marking the sub-windows in the monitoring speckle image corresponding to all the correlation coefficients smaller than a preset threshold value as gas leakage coarse positioning areas; and for each pixel point in the leakage coarse positioning area, calculating a pixel-level imaging operator of the pixel point, and taking the pixel point corresponding to the maximum pixel-level imaging operator as a gas leakage point.
Owner:SOUTHWEST JIAOTONG UNIV

Method for joint inversion of near-seismic body wave three-dimensional quality factor

The invention discloses a joint inversion three-dimensional quality factor method, which comprises the following steps of: acquiring average attenuation travel time through an initial three-dimensional quality factor (Q value) and an average attenuation travel time formula, and acquiring a theoretical frequency spectrum amplitude at the frequency by combining a plurality of initial values including corner frequency, field effect, low-frequency amplitude and frequency and an amplitude formula; converting the displacement frequency spectrum amplitude in the frequency domain into an observation frequency spectrum amplitude in a natural logarithm domain, and obtaining a residual vector formula in combination with a theoretical frequency spectrum amplitude; a formula obtained after meshing of the seismic wave three-dimensional propagation speed and the initial Q value in the average attenuation travel time formula is substituted into a residual vector formula, smooth constraint and damping parameters are added to obtain a new residual vector formula, and the new residual vector formula is solved to obtain a value of a parameter disturbance quantity; superposing the values to the plurality of initial values to obtain a plurality of new initial values of the next round of iteration; and substituting the initial three-dimensional Q value back to a residual vector formula to obtain a residual vector, and taking the new initial three-dimensional Q value as a target three-dimensional Q value when a difference value between the residual vector and the amplitude meets a condition.
Owner:CHANGAN UNIV

Carbon dioxide concentration detection method based on photoacoustic effect multi-frequency modulation anti-interference

The invention belongs to the technical field of carbon dioxide concentration detection, and particularly relates to a multi-frequency modulation anti-interference carbon dioxide concentration detection method based on a photoacoustic effect. Comprising the following steps: S1, enabling infrared light with a certain wavelength to pass through CO2 gas to be detected; s2, periodically modulating the infrared heat source, and flashing according to pulses with different frequencies in the modulation stage; and S3, collecting a sound wave signal through a high-sensitivity MIC, extracting an MIC frequency spectrum amplitude characteristic value, and calculating the CO2 concentration according to a fitting formula of the calibration curve. A traditional fixed frequency modulation mode is broken through, and environment vibration noise is effectively separated through multi-frequency combination.
Owner:SU ZHOU ZE SHENG WEI DIAN ZI YOU XIAN GONG SI

A traceable pressure sensor dynamic response calibration method based on absorption spectrum reference pressure input

PendingCN122360794AFrequency spectrumPressure amplitude
The application discloses a kind of traceable pressure sensor dynamic response calibration method based on absorption spectrum reference pressure input, in shock tube is driven section tail end wall position arrangement to be calibrated pressure sensor, and set optical measurement window in reflected shock action area, synchronous acquisition pressure sensor output signal and absorption spectrum signal;Absorption spectrum signal is preprocessed and spectral line fitting, calculate the gas temperature and collision broadening coefficient after reflected shock wave, and reference pressure amplitude P5 after reflected shock wave is obtained accordingly;Pressure amplitude P1 before incident shock wave is measured using pressure gauge after metrological calibration;According to P1, P5 and pressure mutation time t0 Reference pressure step input signal based on Heaviside step function is constructed;Reference pressure step input signal and pressure sensor output signal are processed, and the ratio of the spectral amplitude of the two is used as the sensitivity of the pressure sensor at the corresponding frequency;Error source in the process of calculating reference pressure amplitude, pressure mutation time and sensitivity is evaluated and calculated, and the sensitivity calibration result of pressure sensor is obtained.The application can obtain the sensitivity characteristics and its uncertainty of pressure sensor.
Owner:SOUTHEAST UNIV

Signal enhancement method, device, OPA laser radar and storage medium

The present application is applicable to the field of signal processing technology, and provides a signal enhancement method, device, OPA laser radar and storage medium. The signal enhancement method includes: obtaining a first frequency spectrum corresponding to each of N difference frequency signals for the target detection object, wherein the first frequency spectrum includes a spectrum serial number and a spectrum amplitude corresponding to the spectrum serial number, where N is an integer greater than 1; performing a dot multiplication operation on the spectrum amplitudes with the same spectrum serial number in the N first frequency spectra to obtain a second frequency spectrum with a signal-to-noise ratio of #imgabs0#, where x1 is the signal-to-noise ratio of a single first frequency spectrum; and determining the frequency of the difference frequency signal based on the second frequency spectrum. The present application can improve the accuracy of the frequency measurement results of the difference frequency signal.
Owner:WUHAN WANJI INFORMATION TECH

A PPG signal lightweight diffusion denoising method, system, device and medium

The present application relates to the field of signal denoising, and provides a PPG signal light-weight diffusion denoising method, system, device and medium, which comprises generating reference noise and obtaining a pure signal to obtain a reference signal; the pure signal is added with noise to obtain a diffusion noise signal; a multi-scale one-dimensional convolution structure is constructed, the diffusion noise signal and the reference signal are respectively convolved through the multi-scale one-dimensional convolution structure to obtain a double-branch feature sequence; light-weight attention calculation is performed on the double-branch feature sequence to obtain an updated double-branch feature sequence, multi-layer residual fusion and noise prediction are performed on the updated double-branch feature sequence to obtain a noise prediction result; the diffusion noise prediction loss, the average spectral amplitude difference and the waveform form loss of the noise prediction result are calculated to obtain a prediction loss, and the target prediction model is obtained through training according to the prediction loss, and the PPG signal is denoised through the target prediction model.
Owner:TIANJIN POLYTECHNIC UNIV

Hyperspectral diffraction imaging device, system and method based on blind coding

The invention discloses a hyperspectral diffraction imaging device, system and method based on blind coding, and relates to the technical field of hyperspectral coherent diffraction imaging.The method comprises the steps that a hyperspectral light beam emitted by a light source is transmitted to a mask plate through a reflector after being subjected to beam expanding, focusing and collimation; controlling the mask plate to move from the first position to the second position, so that the mask plates at different positions before and after movement have overlapped areas along the light path direction, and obtaining a diffraction image of each lamination scanning position; and according to the diffraction image, performing joint reconstruction on the unknown mask plate, the spectrum and the imaging object by using a broadband phase reconstruction algorithm based on multi-parameter constraint to obtain amplitude and phase information of the reconstructed mask plate, the spectrum and the imaging object so as to complete hyperspectral illumination coherent diffraction imaging. According to the method disclosed by the invention, multi-spectrum amplitude-phase-spectrum joint reconstruction of the hyperspectrum under low-time coherent illumination can be realized by utilizing laminated scanning under the condition that codes are unknown.
Owner:SHANDONG UNIV

An ion concentration analysis method and system

The present application relates to the technical field of data processing, and discloses an ion concentration analysis method and system. The method includes: collecting spectral data at multiple monitoring points in the hydroxide ion chamber to obtain an original spectral data set for each monitoring point; respectively performing spectral amplitude, shape, and information difference measurement on the original spectral data set to obtain comprehensive spectral feature data for each monitoring point; inputting the comprehensive spectral feature data of each monitoring point into a preset partial least squares regression model for ion concentration prediction to obtain ion concentration prediction data for each monitoring point; inputting the ion concentration prediction data of each monitoring point into a preset integrated cost-sensitive deep neural network model for ion concentration anomaly detection to obtain a target ion concentration anomaly detection result. The present application improves the accuracy of ion concentration detection in the hydroxide ion chamber.
Owner:深圳微子医疗有限公司

Optical metrology system and method

A measurement system for use in optical metrology, the measurement system which includes a control system configured and operable to carry out the following: (i) receive raw measured data generated by a measurement unit that is configured and operable for performing normal-incidence spectral interferometric measurements on a sample and generating the raw measured data indicative of spectral interferometric signals measured on the sample for a number of different optical path differences (OPDs) between sample and reference arms using infrared wavelengths; (ii) extract, from the raw measured data, a portion of spectral interferometric signals describing variation of signal intensity with a change of an optical path difference OPD during interferometric measurements, said portion of the spectral interferometric signals being independent of interferometric signals returned from a bottom portion of the sample in response to said illuminating electromagnetic field; and (iii) directly determine, from the extracted portion of the spectral interferometric signals, both spectral amplitude and phase of reflection of the illuminating electromagnetic field from the top portion of the sample, thereby enabling to determine a measured spectral signature characterizing the top portion of the sample.
Owner:NOVA MEASURING INSTR LTD

Programmable acousto-optic modulation ultrashort pulse laser control method, device and system

The invention discloses a programmable acousto-optic modulation ultrashort pulse laser control method, device and system. An exemplary ultrashort pulse laser control method comprises the following steps: acquiring a signal parameter of an output light pulse; on the basis of the signal parameters of the output light pulses and the corresponding relation between the output light pulses and ultrasonic waves, the signal parameters of the ultrasonic waves are obtained; generating ultrasonic waves based on the signal parameters of the ultrasonic waves; an input light pulse is modulated using the ultrasonic waves to produce an output light pulse. According to the programmable acousto-optic modulator provided by the invention, the spectral amplitude and phase of the ultra-short pulse laser can be regulated and controlled at will through programming setting, meanwhile, the spectrum does not need to be separated in space like a spatial light modulator, the acousto-optic crystal can be directly inserted into a light path, and the problems of spectral modulation and the like cannot be caused.
Owner:INSTITUTE OF PHYSICS CHINESE ACADEMY OF SCIENCES

Method of suppressing undesired noise in a hearing aid

The invention relates to a method of suppressing undesired noise in a hearing aid, the hearing aid comprising a handheld unit, in which a microphone is integrated, and another microphone located externally of the handheld unit and connected thereto. The method includes the steps of converting a signal from the integrated microphone and a signal from the external microphone into digital signals; dividing the digital signal from the integrated microphone and the external microphone into frequency sub-bands, computing the current spectral amplitude of the integrated microphone sub-band signal and the current spectral amplitude of the external microphone sub-band signal; computing the ratio of the current spectral amplitude of the external microphone sub-band signal to the current spectral amplitude of the integrated microphone sub-band signal; modifying the integrated microphone sub-band signal according to the calculated ratio; and computing a full-band output signal from the integrated microphone sub-band signals.
Owner:ALANGO TECH

A method for detecting target motion direction based on frequency modulated continuous wave laser radar

A method for detecting the direction of target movement based on a frequency modulated continuous wave laser radar, the method comprising: obtaining a first difference frequency signal generated by mixing a transmitting signal and an echo signal within a single frequency sweep period T, the transmitting signal being a signal transmitted by a frequency modulated continuous wave laser radar based on triangular wave modulation, and the echo signal being an echo signal after the transmitting signal is reflected by a moving target; setting the difference frequency signal data of a certain duration t within half a frequency sweep period of the first difference frequency signal to zero to obtain a second difference frequency signal; and determining the speed information of the moving target relative to the laser radar based on the frequency values ​​of the two spectral peaks in the spectrum data corresponding to the second difference frequency signal, the speed information including the speed magnitude and direction. This application establishes a corresponding relationship between the spectrum amplitude and the spectrum of the difference frequency signal in the upper and lower frequency sweep bands, and the speed information between the target and the radar can be obtained by measuring the frequency difference between the upper and lower frequency sweep bands.
Owner:VANJEE TECHNOLOGY CO LTD

Spectral quantitative detection model updating method applied to recessive decision boundary

The invention provides a spectrum quantitative detection model updating method applied to a recessive decision boundary, which comprises the following steps of: (1) collecting spectrum data of an unmarked sample, and obtaining frequency characteristics of a spectrum; (2) calculating the distance between the unmarked sample and the modeling sample on the spectral amplitude characteristic and the spectral frequency characteristic; (3) selecting a valuable sample through a statistical inference algorithm based on the calculated distance between the two types of features; (3) selecting representative samples from the valuable samples by using hierarchical clustering and local linear reconstruction methods, and manually marking label values of the representative samples; and (4) designing a target function for model updating, and updating the model by adopting a batch training method based on an information extraction ratio. The method focuses on the updating problem of the spectrum quantitative detection model, the representative sample is obtained based on the implicit decision boundary mode, and rapid, reliable and low-cost updating of the model is achieved.
Owner:HUZHOU UNIVERSITY

Multi-domain fusion voice noise reduction method and system and computer readable storage medium

PendingCN121983017ADeploy lightweight and excellentExcellent engineering interpretabilitySound producing devicesHigh level techniquesFrequency spectrumAlgorithm
The invention discloses a multi-domain fusion voice noise reduction method and system and a computer readable storage medium, and relates to the technical field of voice enhancement and signal processing, and the method comprises the following steps: recognizing a candidate line spectrum through constructing a power spectrum peak value comprehensive score, and carrying out the adaptive notch; performing compensation in combination with wavelet adaptive threshold processing and improved logarithmic spectrum amplitude estimation; and weighted fusion is further carried out on the signals after wave trapping and compensation through spectrum energy entropy. Rapid suppression of narrowband line spectrum interference is realized through spectrum line peak detection and an adaptive notch technology, broadband background noise is effectively eliminated by means of a wavelet coefficient energy ratio eta adaptive threshold algorithm and an OM-LSA spectrum compensation technology, and recursive robust estimation in a time-frequency domain is completed by adopting frequency domain three-dimensional Kalman filtering. And finally, signal detail reconstruction and spectrum equalization are realized by using a lightweight residual CNN network without training weight, so that the optimal balance of high gain and low distortion is achieved in a complex noise environment.
Owner:NANJING UNIV OF POSTS & TELECOMM