2415 results about "Center frequency" patented technology

The invention provides a satellite-borne multi-band synthetic aperture radar signal processing optimization method and system, and relates to the technical field of signal processing, and the method comprises the steps: obtaining original echo data of a satellite-borne multi-band synthetic aperture radar, carrying out Doppler center frequency estimation, carrying out two-dimensional matrix product operation, and obtaining compensation echo data; distance direction position information and scattering intensity information are obtained based on a distance direction matching filtering algorithm of sub-band decomposition; determining spatial distribution density, performing adaptive block processing, and performing phase error modeling in each block to generate a continuous phase correction function; performing wavelet domain convolution operation to obtain corrected echo data, obtaining a multi-band two-dimensional image, extracting a multi-dimensional feature vector through a deep neural network, performing weight learning, performing nonlinear weighted fusion, and performing adaptive histogram equalization enhancement to determine a synthetic aperture radar imaging result.

The invention discloses a power distribution network state panoramic intelligent sensing method, relates to the technical field of power distribution network monitoring management, and is used for solving the problem of poor power distribution network abnormity monitoring. According to the method, multi-scale decomposition and baseline construction of the signals are realized through accurate acquisition and preprocessing of the node signals of the power distribution network, steady-state and abnormal dynamic characteristics of the power distribution network are effectively extracted, a variational mode decomposition technology is used, and a low-frequency mode is screened through a center frequency to construct a baseline, so that the reliability of the power distribution network is improved. Constructing a robust residual error and an abnormal energy index by combining the difference between a baseline and an original signal, accurately determining an abnormal event, switching a power distribution network node to an ultrahigh frequency sampling mode after abnormal triggering, extracting a local disturbance characteristic by using time domain difference, and adaptively adjusting a filtering parameter according to a local edge ratio through robust filtering noise reduction, so as to achieve the purpose of reducing noise. Therefore, the abnormal edge information is fully reserved, the real-time and high-precision perception of the abnormal state of the power distribution network is realized, and the response speed and accuracy of the panoramic perception of the power distribution network are improved.

The invention provides a multi-band radio frequency power amplifier dynamic range adaptive test method and a system thereof. The method comprises the following steps: acquiring an output signal frequency spectrum of a tested radio frequency power amplifier, extracting characteristic frequency points including a center frequency and a bandwidth, matching the characteristic frequency points with a preset frequency band database, and automatically loading a test scheme of a corresponding frequency band. According to the method, the frequency bands are automatically matched through spectrum sensing, the test scheme is loaded, the multi-frequency-band characteristics can be rapidly adapted without manual parameter configuration, index missing test is avoided, and the switching efficiency is improved; dynamically optimizing test parameters by using a genetic algorithm, and accurately capturing a nonlinear distortion critical point while balancing coverage and efficiency; by combining multi-dimensional signal analysis and a deep learning model, the problem of missing detection of traditional single-domain analysis is solved, and the abnormal signal recognition capability is remarkably enhanced; through linear model correction, impedance dynamic matching and index threshold iteration, full automation and high precision of the test are realized, the environmental interference influence is effectively reduced, and a self-adaptive test system is constructed.

The invention belongs to the technical field of time series prediction, and more specifically relates to a time series data prediction method based on a deep integrated learning model and high and low frequency separation. The method comprises the following steps: collecting time sequence data in a system, and preprocessing the obtained data; vMD variational mode decomposition is carried out on original time sequence data, and a time sequence is decomposed into K mode components with limited bandwidth; combining a maximum information coefficient method and a reconstruction error analysis method to determine an optimal decomposition mode number K; dividing high and low frequency components for all decomposed modes by using a zero-crossing rate and a center frequency; appropriate prediction models are established for the high-frequency component and the low-frequency component respectively; and superposing all modal prediction results to obtain a final time sequence prediction result. According to the method, multiple deep learning models are combined, so that the prediction method has higher flexibility and adaptability, and proper models can be selected for components with different characteristics for prediction, thereby improving the overall performance.

A base station generates a punctured synchronization signal block (SSB) for a channel of a frequency band based on a SSB. A bandwidth of the SSB exceeds a bandwidth of the channel. The punctured SSB includes a punctured physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS). The PSS of the punctured SSB has a center frequency indicated by a sync raster location of a set of sync raster locations associated with the frequency band. The punctured PBCH is obtained from a PBCH of the first SSB based on a puncture pattern associated with the sync raster location. The base station transmits the punctured SSB in the channel. A user equipment (UE) detects the punctured SSB according to the sync raster location.

The present invention relates to the technical field of power source power allocation. Disclosed are a direct current power source power allocation method and system for a generator status monitoring apparatus. The method comprises the following steps: by means of system data, constructing a variational problem model; solving the constructed variational problem model, and using a particle swarm optimization algorithm to optimize computing parameters of the variational problem model; and, on the basis of a computing result of the variational problem model, allocating the total output power of a hybrid energy storage system to an energy-type storage device and a power-type storage device according to a ratio. By means of using the convergence-guaranteed particle swarm optimization algorithm, the present invention not only excels in the solving speed but also shows significant advantages in computational accuracy; furthermore, by means of solving the variational problem model, more accurate allocation ratios are obtained; variational mode decomposition can achieve adaptive matching of the optimal center frequency and bandwidth for each mode, thus effectively separating intrinsic mode components and achieving frequency domain partitioning of signals.

The invention relates to the field of electric power material warehouse management and control, in particular to an electric power material digital intelligent professional warehouse management and control method, which comprises the following steps: acquiring electromagnetic spectrum data, identifying a central frequency point energy distribution diagram and an electromagnetic interference intensity level, constructing a three-dimensional electromagnetic field intensity distribution model of a professional warehouse, and dynamically adjusting the working mode of an RFID reader-writer; the method comprises the following steps: deploying a multi-modal check node in a storage area of a professional warehouse, and generating a composite check result through an infrared contour matching method and a UWB coordinate verification method when the confidence coefficient of electric power material data read by an RFID reader-writer is lower than a preset confidence coefficient threshold value; updating an electric power material inventory database according to a composite verification result, and performing electric power material inventory state analysis in real time through an edge computing node; the problems that inventory data distortion and material positioning deviation are caused by reduction of the accuracy rate of RFID in a strong electromagnetic environment, and inventory accuracy management of an electric power material warehouse is seriously restricted are solved.

The invention belongs to the technical field of radar signal processing and target identification, and particularly relates to a maritime hybrid target identification method and system based on modal decomposition and reconstruction, and the method comprises the steps: carrying out the variational modal decomposition of a radar echo signal of a maritime hybrid target, and decomposing an original signal into a plurality of intrinsic modal signals; estimating a background noise energy reference and removing noise modals based on the decomposed modal signals, clustering the remaining modals according to the center frequency, and combining the modals with the frequency within the center frequency range into an independent single-target signal which is of the same target and is reconstructed into an independent single-target signal; respectively carrying out time-frequency analysis on each reconstructed single target signal to obtain a corresponding time-frequency diagram, and extracting time-frequency domain features from the time-frequency diagram; and inputting the extracted features into a trained support vector machine classifier to realize automatic identification of the ship target and the floating target. A ship target and a floating target can be distinguished more accurately in a mixture scene, and the stability of tracking identification is improved.

The present invention discloses a neural network accelerated simulation method for the radar scattering field of a wide-band target group, belonging to the technical field of electromagnetic simulation. The method of the present invention constructs a KAN neural network model at the central frequency of the wide band, and constructs KAN neural network models at other target frequencies through transfer learning or direct training; uses the trained KAN neural network model to generate a multi-frequency point numerical Green's function data set, and then constructs a wide-band training sample to train the multi-task learning model to realize the global prediction of the numerical Green's function of the entire target wide band; uses the numerical Green's function output by the multi-task learning model to realize the fast simulation of the scattering field of the wide-band target group. The method of the present invention can realize the fast and accurate simulation of the radar scattering field of the wide-band target group.

The invention relates to a nonlinear ultrasonic guided wave phased array imaging method based on mixed array elements and time reversal. The method comprises the following steps: exciting a fundamental wave and receiving a second harmonic wave at piezoelectric array elements of the fundamental wave and the second harmonic wave of an ultrasonic guided wave by using a center frequency respectively; full-matrix data of ultrasonic guided wave signals in the detected workpiece are obtained in a one-transmitting and one-receiving mode; a fundamental wave signal is suppressed and a second harmonic signal is enhanced by adopting a pulse inversion mode; for the full-matrix data after pulse inversion, utilizing continuous wavelet transform filtering to extract a second harmonic signal; respectively calculating the distance from the discretized imaging area to the excitation array element and the distance from the discretized imaging area to the receiving array element; and for each discrete pixel point, according to an excitation signal of a distance forward propagation fundamental wave and a received second harmonic signal back propagation, a pixel value is calculated by using a time domain topology energy equation, and local acoustic nonlinear imaging of the plate-shaped structure is realized.

The invention discloses an optical cable icing galloping online monitoring system based on a BOTDR, and belongs to the technical field of distributed optical fiber sensing. The system comprises an optical module, a signal processing module and a data processing module, the optical module is used for generating a detection light signal and interacting with a sensing optical fiber to obtain a Brillouin scattering signal, and then the Brillouin scattering signal is converted into an electric signal; the signal processing module is used for performing frequency down-conversion, signal filtering and digital acquisition on the electric signal to obtain multiple groups of Brillouin scattering signal data; the data processing module is used for processing the multiple groups of Brillouin scattering signal data and extracting a Brillouin frequency shift center frequency; temperature and strain distribution along the optical cable is obtained according to the frequency shift, and temperature and strain states are transmitted to a QT upper computer through PCIE for real-time display. According to the invention, high-precision and long-distance optical cable icing galloping monitoring can be realized, reliable early warning and safety guarantee are provided, and technical support is provided for maintenance and management of an electric power system.

The invention provides a bridge dynamic displacement measurement method based on an unmanned aerial vehicle, and relates to the field of bridge health monitoring, and the method comprises the steps: obtaining a bridge image sequence through the unmanned aerial vehicle; obtaining transformation matrixes according to the relation between the other frames of images and the fixed measurement points of the reference frame, correcting the coordinates of the motion measurement points of the corresponding frames of images according to the transformation matrixes, obtaining a corrected bridge image sequence, and further obtaining an initial displacement signal; variational mode decomposition is carried out on the initial displacement signal, a constraint variational optimization problem is constructed, the optimization problem is solved through iteration to obtain each mode component of variational mode decomposition and a corresponding center frequency, and a low-frequency mode component is removed to obtain a displacement signal after secondary correction of the influence of the unmanned aerial vehicle; and obtaining the real displacement according to the scale factor between the image obtained by the unmanned aerial vehicle and the real world. The influence caused by the movement of the unmanned aerial vehicle is corrected, and the accuracy, reliability and stability of a measurement result are effectively improved.

The invention discloses a power distribution network high-resistance grounding fault detection method and system, and relates to the technical field of power distribution network fault detection. A power distribution network high-resistance grounding fault detection method comprises the following steps: S1, collecting a transient zero-sequence voltage signal of a target feeder line as a to-be-decomposed electric quantity signal; s2, variational mode decomposition is carried out on the to-be-decomposed electric quantity signals, mode functions obtained by decomposing the single to-be-decomposed electric quantity signals are arranged according to the center frequency from low to high, and one-dimensional feature vectors of the to-be-decomposed electric quantity signals are obtained; and S3, inputting the one-dimensional feature vector of the electric quantity signal to be decomposed into a pre-constructed Transform model to obtain a detection result. According to the method, the high-resistance grounding fault and the disturbance condition can be accurately identified, the fault identification accuracy is very high, and the power distribution network fault detection efficiency is improved.

The invention discloses an ultra-low phase noise microwave signal generation method and system based on an electro-optical comb. The method comprises the following steps: 1) locking two lasers with continuously tunable wavelengths in the same FP cavity through two links with different modulation frequencies to realize a dual-wavelength laser with a frequency interval of (v2-v1); 2) reducing the electronic noise of each link to a quantum noise limit by using a residual amplitude modulation noise control technology; 3) coupling the lasers with the center frequencies of v1 and v2 into one path, inputting the laser into an electro-optical frequency comb generator, and generating two sets of electro-optical frequency combs with spectrum overlapping; (4) beat frequency signals of the two electro-optical frequency combs are obtained; the beat frequency signal and a reference signal from a reference signal source are accessed to a phase discriminator for phase discrimination; an output signal of the phase discriminator is sent to a proportional-integral-differential control circuit; and 5) controlling the phase noise of the radio frequency source by using the output feedback of the proportional-integral-differential control circuit to obtain an ultra-low phase noise microwave signal.

The invention discloses a method for estimating the transmittance of a time-varying channel based on a frequency division multiplexing pilot frequency, and aims to solve the problem that the existing method for estimating the transmittance by adopting average transmittance does not have the capabilities of timely feedback and dynamic adjustment. The method comprises the following steps of: measuring a regular position component and a regular momentum component of a received signal by receiving a quantum signal and a pilot signal of frequency division multiplexing in a local local oscillator continuous variable quantum key distribution system generated by a transmitting end in real time; compensating phase noise caused by frequency offset and channel jitter due to different center frequencies of two independent lasers at a receiving end and a transmitting end by using a frequency offset compensation and phase recovery algorithm, and performing band-pass filtering to obtain a recovered pilot signal; and calculating the power ratio of the obtained pilot signal to the pre-calibrated pilot signal at each moment to obtain the time-varying free space transmittance. The performance change of the system in different time periods can be accurately reflected, the communication performance of the CVQKD system can be optimized, the success rate of key transmission can be improved, and the adaptability and robustness of the system can be improved.

Disclosed are techniques for wireless communication. In an aspect, a network node receives, from a network entity, a configuration for reporting carrier phase measurements of one or more reference signal resources spanning a plurality of subcarriers, wherein the configuration indicates one or more center frequencies to use for reporting the carrier phase measurements, obtains one or more carrier phase measurements of the one or more reference signal resources based on the one or more center frequencies, and reports, to the network entity, the one or more carrier phase measurements.

The invention provides a sound source imaging calculation method and system, electronic equipment, a storage medium and a computer program product, and the method comprises the steps: carrying out the preprocessing of obtained audio data, so as to obtain a center frequency in a scanning frequency range, and the audio data are collected through a microphone array; sound intensity grids are divided within the visible range of the video collection device. And determining an Euclidean distance matrix and an array steering vector from the microphone array to the sound intensity grid. And obtaining an output power spectrum matrix according to the array steering vector and the cross-spectrum matrix. And coloring the sound intensity grids to obtain a thermodynamic diagram. The sound source imaging method is optimized and innovated by utilizing the parallel computing capability of the CUDA technology, the accurate positioning of the sound source is realized, the processing speed and the positioning precision of the CUDA architecture model are improved, and powerful technical support is provided for the development of the sound source imaging field.

A reconfigurable intelligent surface (RIS) may include multiple sub-RIS, and the base station may configure the RIS and the multiple sub-RIS with RIS sync raster including multiple center frequencies. The RIS may be configured to simultaneously apply different water-markings and reflect the incident beam into different beams in different directions. The base station may perform a beam-sweeping by transmitting synchronization signal blocks (SSBs) on multiple SSB beams, and the RIS may receive one SSB beam of the multiple SSB beams and reflect the SSB beams on the RIS sync raster. A UE may be configured to monitor the base sync raster and the RIS sync raster for a suitable SSB beam, and transmit a feedback report to the base station indicating the suitable beam. The base station may configure the RIS based on the feedback report received from the base station for beam management.

A centimeter-resolution integrated photonic millimeter-wave (mmWave) radar chip operating in the mmWave V band based on a 4-inch wafer-scale thin-film lithium niobate (TFLN) technology is provided. The fabricated TFLN photonic mmWave integrated circuit has a first electro-optic modulator (EOM) capable of generating a broadband linear frequency modulated mmWave radar waveform through optical frequency multiplication of a low-frequency input signal, and a second EOM for frequency de-chirp of the reflected echo wave, thereby greatly relieving bandwidth requirements for the digital-to-analog converter in the transmitter and analog-to-digital converter in the receiver. In the absence of optical and electrical filters, the radar chip features continuous on-demand tunability of the center frequency and bandwidth, currently only limited by the bandwidths of electrical amplifiers. The radar chip provides a promising way to achieve high resolution sensing and detection for vehicle radar, airborne radar, and smart home in the 6G era.

The invention requests to protect a rolling bearing fault diagnosis method based on envelope spectrum knowledge distillation. The method comprises the following steps: obtaining a rolling bearing vibration signal, and carrying out sample division and normalization processing; the spectral kurtosis of the source working condition sample is calculated, the center frequency and bandwidth of envelope demodulation are determined according to the spectral kurtosis, envelope demodulation is carried out, and the demodulation sample is sent to a teacher network phi for pre-training; respectively inputting an original vibration sample and an envelope spectrum sample under a source working condition into a student network psi and a pre-trained teacher network phi, and extracting bearing health state representations learned by the two networks to establish envelope spectrum knowledge distillation loss; calculating the prediction loss of the student network, the cross-working-condition sample probability distribution alignment loss and the diversity loss represented by the health state; carrying out multi-loss back propagation, and optimizing the weight and bias of the fault diagnosis network by adopting an Adam optimizer; and finally, inputting the target working condition sample into the trained fault diagnosis model for performance testing.

The invention discloses a multipath interference suppression method and device during in-pipe detection and a storage medium, and belongs to the technical field of radar signal processing. According to the method, a CFAR detection and clustering algorithm combined method is adopted, and the target number and the center frequency are automatically extracted from a radar amplitude-frequency signal; an original noisy signal is decomposed into a target number of modal components by using an improved variational modal model, and an improved power reference analysis method is proposed to divide the modal components into effective modals and ineffective modals; sVD noise reduction is carried out on the effective mode; and performing signal reconstruction on the plurality of modal components after SVD noise reduction to obtain a signal after multipath interference suppression. According to the method, the problem that the decomposition number and the center frequency of the variational mode decomposition algorithm are difficult to determine is effectively solved, the influence of inaccurate parameters is reduced, multipath interference suppression during complex environment detection is facilitated, and the effectiveness of the algorithm is verified through actual measurement.

The invention provides a low-frequency signal receiving device, belongs to the technical field of low-frequency communication, and designs a large-gain isolation direct amplification and variable center frequency band-pass filter to replace a traditional frequency conversion receiver, so that the scale of a circuit is effectively reduced to 1 / 3 of that of the original frequency conversion receiver; front isolation amplification is designed, the two-stage automatic gain circuit has high-sensitivity 16 dB to 126 dB large dynamic range receiving capacity, isolation segmentation amplification is designed, a frequency-adjustable narrow-band filter is inserted in the middle of cascade connection of the two-stage automatic gain circuit in a penetrating mode to prevent circuit self-excitation, and direct large gain amplification stability is improved. The bandwidth of the two-stage frequency-adjustable narrow-band filter ranges from 400 Hz to 1200 Hz, the gradient coefficient is smaller than 4, and out-of-band interference can be effectively restrained. A 10dB-80dB amplifier is designed in front of a frequency-adjustable narrow-band filter, so that the noise of an LTC1068-25 switched capacitor filter is overcome, and the received noise of the whole machine is smaller than 5nV / Hz1 / 2. According to the invention, light, stable and miniaturized underwater receiving capability is realized, and the antenna is suitable for application scenarios with high requirements on power consumption and space, such as UUV and the like.

The invention discloses a method for jointly detecting corrosion defects of a pressure pipeline by utilizing multiple guided wave modes, relates to an ultrasonic non-destructive testing technology, and is used for solving the problem that the accuracy is relatively low when a single guided wave mode is used for detecting. The method for detecting the corrosion defect of the pressure pipeline comprises the following steps: calculating ultrasonic guided wave dispersion data of the pressure pipeline, and determining the center frequency of a transducer according to the dispersion data; the method comprises the following steps: arranging ultrasonic transducer annular arrays on two sides of a to-be-detected pressure pipeline, and acquiring ultrasonic guided wave data detected by the pressure pipeline in an L (0, 1) mode and a T (0, 2) mode; preprocessing the array waveform data to obtain detection data which can be used for guided wave imaging; according to the L (0, 1) mode guided wave data, a full waveform inversion method is adopted to invert the wall thickness of the pipeline corrosion defect; judging whether the pipeline defect exceeds the detection depth range of the T (0, 2) mode, and if the pipeline defect exceeds the detection depth range, ending; and if not, inverting the wall thickness of the pipeline corrosion defect by adopting a full-waveform inversion method according to the T (0, 2) mode guided wave data.

The invention discloses a LoRa-based parallel backscatter communication method and system. The method comprises the following steps: transmitting a single-tone radio frequency source signal as a signal excitation source; designing a backscattering label, and performing backscattering modulation processing on the environmental perception data in combination with the signal excitation source to obtain a modulated standard LoRa data packet; and the receiver presets the center frequency of a communication link, and performs frequency band distinguishing and demodulation processing on the modulated standard LoRa data packet to complete parallel backscatter communication of the LoRa data. According to the invention, while a parallel backscattering LoRa communication system compatible with commercial LoRa equipment is realized, the throughput of the system is improved, and frequency division multiple access parallel transmission is realized. The LoRa-based parallel backscatter communication method and system can be widely applied to the technical field of parallel backscatter communication.

The invention relates to the technical field of MEMS gyroscopes, in particular to a mode matching MEMS gyroscope temperature self-compensation control system and method, and the system comprises a driving mode control subsystem which is used for carrying out closed-loop control on the phase and amplitude of the driving mode of an MEMS gyroscope; the detection mode control subsystem is used for carrying out closed-loop control on the gain of a band-pass filter of an MEMS gyroscope detection mode and enabling the center frequency of the band-pass filter to be matched with the resonant frequency of the detection mode; force coupling is carried out between the driving mode control subsystem and the detection mode control subsystem through the Coriolis effect. The gain of the band-pass filter is adjusted based on the real-time change of the quality factor of the detection mode, and the center frequency of the band-pass filter is matched with the resonant frequency of the detection mode, so that the suppression and self-compensation of the temperature drift of the gyroscope are realized.

The invention discloses a signal acquisition and processing method and system based on a multifunctional radar, and relates to the technical field of signal acquisition and processing, and the method comprises the steps: employing a quantum genetic algorithm to optimize radar transmission waveform parameters, including center frequency, bandwidth and frequency modulation slope, and generating a nonlinear frequency modulation waveform through FPGA hardware; a non-uniform sparse array is adopted to receive a target echo signal, time domain random interval sampling and frequency domain pseudo-random frequency point selection are synchronously implemented, and time-space-frequency three-dimensional compressed sensing observation data are formed; performing trilinear tensor joint sparse reconstruction on time-space-frequency three-dimensional compressed sensing observation data, decomposing a polarization scattering matrix eigenvalue from a reconstructed signal, and calculating a coupling characteristic quantity of eigenvalue entropy and micro-Doppler frequency; inputting the coupling characteristic quantity into a deep reinforcement learning model, and dynamically outputting a constant false alarm detection threshold, a moving target display filter order and a resource allocation weight; and detecting a threshold based on a constant false alarm rate.

Example systems and methods for radio-frequency adversarial deep-learning inference for automated network coverage estimation include a generative adversarial network (GAN) based approach for synthesizing RF maps in indoor scenarios. In some examples, a semantic map is utilized—a high-level representation of the indoor environment to encode spatial relationships and attributes of objects within the environment and guide the radio frequency (RF) map generation process. A new gradient-based loss function is introduced that computes the magnitude and direction of change in RSS values from a point within the environment. Some examples incorporate this loss function along with the antenna pattern to capture signal propagation within a given indoor configuration and generate new patterns under new configuration, antenna (beam) pattern, and center frequency.

The invention discloses a composite fault signal separation method based on adaptive spectral kurtosis deconvolution. The method comprises the following steps: S1, carrying out noise reduction processing on an original composite fault signal; s2, separating the composite fault signal after noise reduction through Hilbert envelope demodulation; s3, optimizing a low-pass filter and a high-pass filter through a Bayesian objective function, and constructing a band-pass filter and a band elimination filter; and S4, carrying out iterative filtering on the composite fault signal after noise reduction through a band-pass filter and a band elimination filter, constructing a frequency-bandwidth fast spectral kurtosis graph according to a fast spectral kurtosis deconvolution method, obtaining a center frequency and bandwidth range corresponding to the maximum spectral kurtosis, and separating out the weak fault signal in the step S2. According to the method, a spectral kurtosis graph is constructed by combining a low-pass filter and a high-pass filter through a fast spectral kurtosis deconvolution method to determine the center frequency and the bandwidth range, targeted separation is carried out on composite fault signals, an initial filtering parameter range is provided for Bayesian optimization, and the fault separation efficiency and accuracy are improved.

The invention discloses a hydroelectric generating set state online monitoring system and method based on data analysis, and relates to the technical field of data analysis. The method comprises the following steps: setting a training period, extracting a time domain feature vector and a frequency domain feature vector of each data packet, and training to generate a gated attention mechanism model; training and generating a mixed density network model according to the data packet containing the fault state label; according to the real-time fault risk probability, the latent variable representation vector and the real-time center frequency, whether abnormal features are analyzed or not is judged, if the abnormal features are analyzed, the contribution degree of each input feature to the real-time fault risk probability is calculated through a gradient approximation method, and an influence degree score is calculated; and taking the corresponding input features exceeding the influence degree score threshold as abnormal features, and outputting prompt information for operation and maintenance personnel to check, thereby improving dynamic environment response, identification precision degree and reliability of a monitoring system.

The invention belongs to the technical field of metal crack detection, and discloses a metal microcrack ultrasonic detection method, which comprises the following modules: an ultrahigh frequency composite array probe with a center frequency dynamic adjustable range of 5-50 MHz; the dual-mode excitation and receiving module is used for independently generating a pulse reflection mode excitation signal and a diffraction mode chirp frequency modulation signal; the phase-controlled synthetic aperture dynamic focusing module is used for realizing + / -60-degree deflection and sub-wavelength level focusing of acoustic beams; the nonlinear harmonic enhancement module is used for exciting a crack nonlinear effect by superposing 1-2MHz fundamental waves; and a time-space-frequency three-domain data fusion module. According to the method, signal-to-noise ratio collapse caused by the diffraction effect in a traditional method is overcome, more importantly, the system has low-frequency penetrability and high-frequency resolution at the same time due to 80%-120% of broadband coverage of chirp frequency modulation signals, the diffraction signal gain is increased by 20 dB or above, a near-surface blind area is compressed to be within 0.2 mm, and the system can be applied to the field of radar imaging. And the core pain point of missing detection of the near-surface microcracks of the thin-wall component is solved.