3217 results about "Transducer" patented technology

The invention provides a gas ultrasonic transducer fast matching method, device and equipment and a storage medium, original measurement data such as flight time are obtained by deploying an ultrasonic transducer in a gas ultrasonic flowmeter in a gas conveying pipeline, and multi-dimensional data acquisition is carried out in combination with other sensor parameters. Wavelet noise reduction and dynamic time warping processing are carried out on collected signals, signal quality and time sequence consistency are improved, time domain, frequency domain, environment and statistical features are extracted, and multi-dimensional feature vectors are formed. Modeling is carried out through a time sequence feature branch and an environment feature branch, weighted fusion is carried out by adopting an attention mechanism, and the recognition capability of the model on key features is enhanced. A machine learning model is trained based on fusion features, a multi-objective loss function and a data enhancement strategy are adopted, the prediction precision and generalization ability of the model are improved, and a compensation value is output to calibrate the original traffic in real time. According to the method, the accuracy and stability of gas flow measurement in a complex environment are effectively improved, and the method has a good engineering application prospect.

The invention relates to the technical field of fluid measurement, in particular to a multimode signal fusion and self-adaptive processing ultrasonic flowmeter and a measuring method. The multimode signal fusion and self-adaptive processing ultrasonic flowmeter comprises an ultrasonic transducer, a signal generation driving module, a signal receiving and conditioning module, a control module, a signal processing module, a signal quality evaluation module and a sound velocity calculation and compensation module. According to the method, the time difference method and Doppler method signals are fused, the self-adaptive processing strategy is adopted to improve the measurement precision of the low-flow-velocity fluid and the impurity-containing fluid, the measurement precision of the low-flow-velocity fluid can be remarkably improved, the adaptability to complex fluid is enhanced, the overall measurement reliability is improved, the Doppler method precision is optimized, and the intelligent degree is high.

The invention discloses a double-frequency anti-interference ultrasonic water meter and a metering method thereof, and relates to the technical field of fluid metering. A 500kHz sound velocity reference channel is constructed in a self-transmitting and self-receiving mode of a single transducer, the sound path length under solidified pure water is calibrated through a factory, the current water quality sound velocity is calculated in real time in a zero flow state, the zero offset of a 1MHz main channel is dynamically corrected, and a high-precision temperature sensor is omitted. Meanwhile, online water quality diagnosis is realized by utilizing a double-frequency cooperation mechanism: turbidity is quantized according to the amplitude ratio of 500kHz and 1MHz signals (based on the characteristics of high-frequency scattering sensitivity and high low-frequency penetrability), and bubbles are detected according to the time domain volatility of the 1MHz signals; and dynamically optimizing the flow metering precision of the main channel according to a diagnosis result by combining a sound velocity compensation model (the sound velocity is inversely proportional to the turbidity) and a graded bubble compensation model (the sound velocity or the flow is corrected according to the volatility). According to the method, medium interference is effectively overcome, measurement reliability is improved, and real-time monitoring and reporting of basic water quality (turbidity and bubbles) are achieved at low cost.

The invention relates to a method (100) for correcting measured values ​​of a mean flow velocity of a medium flowing through a pipeline, determined by means of an ultrasonic flow meter (1), wherein several ultrasonic transducers (10) are arranged on or in the pipeline (50) or a measuring channel (60) integrated into the pipeline and span an arrangement of at least three signal paths, wherein an electronic unit (20) operates the ultrasonic transducers, evaluates measurement signals from the ultrasonic transducers and outputs corrected measured values ​​of the mean flow velocity, where the electronic unit is used at each time period - using the measurement signals from ultrasonic transducers for each signal path, a local flow velocity of the medium is calculated, - calculated at least one, in particular dimensionless, functional relationship between local flow velocities from calculated local flow velocities, - calculates a baseline measurement for the average flow velocity from at least one specific local flow velocity, the base measurement value is corrected and output using a correction factor determined by comparison.

The invention relates to the technical field of sewage detection, provides an intelligent detection method for suspended particles in coking sewage based on image deep learning, and aims to solve the problems of detection lag and low precision in the prior art. According to the technical scheme, the method comprises the following steps: synchronously acquiring sound wave and image data through a high-frequency ultrasonic transducer and an industrial camera, and extracting acoustic parameters and optical characteristic parameters; using a dual-channel convolutional neural network to fuse features, and combining a cross-modal attention mechanism to perform dynamic weighting; and outputting a particle concentration classification result and a particle size distribution prediction value through a multi-task learning model, and performing online learning to compensate environmental interference factors. The device is mainly used for realizing real-time and high-precision suspended particle monitoring and automatic process adjustment of coking sewage treatment.

The invention relates to the technical field of semiconductors, in particular to an ultrasonic transmitting circuit, a chip and an ultrasonic module. The ultrasonic transmitting circuit comprises a first control circuit and a signal generating circuit. The first control circuit is used for outputting a first control signal; the signal generation circuit is used for outputting a driving signal according to the first control signal; the driving signal is used for driving a first booster circuit to output an excitation signal, and the voltage of the excitation signal is higher than that of the driving signal; the excitation signal is used for exciting the ultrasonic transducer to emit ultrasonic waves. According to the embodiment of the invention, the energy of ultrasonic waves emitted by the ultrasonic transducer can be improved, so that the ultrasonic receiving circuit can receive echoes with higher energy, and the sensitivity and the signal-to-noise ratio of ultrasonic detection are improved.

The invention relates to the technical field of underwater acoustic engineering and ocean exploration, in particular to a multi-channel underwater acoustic signal transmitting and measuring system and a signal processing method, which are used for solving the problems that the existing multi-channel underwater acoustic signal processing generally depends on fixed threshold detection or simple time sequence alignment, and the signal processing efficiency is low. The problem that residual vibration, local noise abrupt change or multipath reverberation is easily misjudged as an effective first arrival signal in a complex underwater environment due to the fact that the influence of the physical response characteristic of a transducer on emission time calibration is not considered and effective verification on whether a candidate arrival structure accords with a sound wave propagation physical rule is lacked is solved. According to the invention, a multi-channel energy time sequence and hydrophone space geometrical relationship is fused through an underwater sound propagation initial physical judgment module, a judgment mechanism is constructed based on distance-time consistency of sound propagation, and self-consistent verification is realized by combining a cross-channel arrival sequence and sound velocity constraint. And the accuracy, the robustness and the physical interpretability of the judgment of the effective launching time of the underwater sound are obviously improved.

The invention discloses an ultrasonic transducer series resonant frequency tracking method and an ultrasonic driving power supply, and the tracking method comprises the steps: calculating a current phase difference between a voltage signal and a current signal, determining a phase difference error and an error change rate through the combination of a target phase difference, and determining the resonant state of an ultrasonic transducer according to the comparison of the phase difference error and an error threshold value; if the current driving frequency is in the resonance state, keeping the current driving frequency unchanged; and if in a non-resonant state, correcting the driving frequency through a fuzzy PID algorithm. In order to cope with the sudden change of the load, the tracking method introduces an AI model to identify the load and predict the optimal driving frequency, and then the predicted optimal driving frequency is used as the current driving frequency. According to the invention, the response speed and the adjustment precision in dynamic frequency tracking are improved, and adaptive resonance driving and frequency control of the ultrasonic transducer under variable load and variable working conditions can be realized.

The invention provides a driving and sensing integrated soft claw, gripper and method, and belongs to the field of deep sea soft grippers. The problems that a traditional soft gripper sensor is prone to forming stress concentration and cannot achieve multi-point sensing are solved. The driving and sensing integrated soft claw comprises a sensing layer, an acoustic wave guide main flow channel extending in the length direction is arranged on the sensing layer, and an ultrasonic transducer is arranged on the side, close to the fixed end of the sensing layer, of the acoustic wave guide main flow channel. The end face of one side of the sensing layer is a grabbing face, and a plurality of evenly-arranged protrusions are arranged in the acoustic wave guide main flow channel corresponding to the end face. And the driving layer is arranged on the side, away from the grabbing face, of the sensing layer, a plurality of deformation cavities communicating with the acoustic wave guide main flow channel are formed in the driving layer, the driving layer is in a stretching state in a normal state, and when the deformation cavities are filled with liquid and pressurization continues, the deformation cavities are used for deforming to drive the sensing layer to bend. The manipulator is mainly used for grabbing actions.

The invention relates to the technical field of medical equipment, and provides a focused ultrasound system with multiple treatment modes. The drive circuit comprises a signal generation module which outputs a first ultrasonic generation signal suitable for a thermal ablation mode or a second ultrasonic generation signal suitable for a histotripsy mode; the energy amplification module comprises a signal end, a power supply end and an output end coupled with the ultrasonic transducer; the energy amplification module comprises an isolation driving circuit which outputs a first switch driving signal and a second switch driving signal which are opposite based on an input ultrasonic generation signal; and the power amplification circuit comprises a second switch unit and a first switch unit which are set to be in opposite switch states by opposite driving signals so as to output ultrasonic driving signals to excite the ultrasonic transducer to form focused ultrasound in a histotripsy mode or a thermal ablation mode. The driving circuit is simple in structure and easy to realize, and can meet power supply requirements of various modes such as thermal ablation, histotripsy and the like.

A touch-sensing system includes a cover stack, piezoelectric capacitors, and a signal processor. The piezoelectric capacitors are mechanically coupled to the cover stack at its inner interface. There is a first array of the piezoelectric capacitors which are configured as piezoelectric ultrasonic transducers (PUTs). There is a second array of the piezoelectric capacitors which are configured as piezoelectric force-measuring elements (PFEs). The signal processor is configured to receive PUT array signals from the PUTs and PFE array signals from the PFEs. The signal processor is configured to calculate PUT centroid data from the PUT array signals and PFE centroid data from the PFE array signals. The signal processor is configured to determine an estimated touch position on the cover stack by combining applicable centroid data including the PUT centroid data and the PFE centroid data.

The invention provides an electrochemical biosensor based on ultrasonic bidirectional driving and a detection method, and belongs to the technical field of biosensing. The sensor comprises a porous membrane and an ultrasonic bidirectional driving unit, and a probe capable of specifically capturing a target object is fixed in a pore channel of the porous membrane; the ultrasonic bidirectional driving unit is composed of a first ultrasonic transducer and a second ultrasonic transducer which are symmetrically arranged on the two sides of the porous membrane, and can synchronously execute reverse power gradient change to form alternately changing pressure difference on the two sides of the membrane so as to drive liquid to repeatedly penetrate through the porous membrane. The detection method comprises the steps of to-be-detected liquid injection and ultrasonic bidirectional driving, ultrasonic auxiliary cleaning and electrochemical detection. The problems of insufficient probe utilization rate, low mass transfer efficiency and non-specific adsorption of a traditional passive diffusion mechanism are solved by utilizing bidirectional ultrasonic active driving force, the detection sensitivity, speed and signal-to-noise ratio are remarkably improved, and the method is suitable for rapid and high-sensitivity quantitative analysis of various analytes.

The invention relates to the technical field of wind turbine generator maintenance, and discloses a wind turbine generator blade unmanned aerial vehicle deicing assembly and method.The wind turbine generator blade unmanned aerial vehicle deicing assembly comprises an unmanned aerial vehicle, and a laser radar and an installation shell integrating an ultrasonic transducer, a pulse nozzle and a hydraulic pump are installed at the bottom of the unmanned aerial vehicle. The deicing control system obtains focus space coordinates and interface resonance frequency of the blade surface by using a space state sensing module; the stress field focusing module calculates the phase delay amount of the ultrasonic transducer, compensates the pose deviation of the unmanned aerial vehicle by adjusting the emission time sequence, and drives the ultrasonic transducer to generate resonance stress on an ice layer-skin interface; and the sound stream synchronous control module determines a jet flow triggering moment according to synchronous phase locking solution, drives a pulse nozzle at an instantaneous negative pressure phase point of a sound wave period to inject a small amount of deicing fluid into an interface crack, and generates shear stress to induce the interface crack to expand and peel off an ice layer. Accurate throwing of deicing energy is achieved, and the icebreaking efficiency is improved on the premise that the safety of the blade structure is guaranteed.

The embodiment of the invention provides an ultrasonic transducer, a preparation method of the ultrasonic transducer, an ultrasonic fingerprint module and electronic equipment. The ultrasonic transducer comprises a substrate, a bottom electrode, a piezoelectric layer, a top electrode and an excitation electrode, the bottom electrode is located on the upper surface of the substrate, the piezoelectric layer is located above the substrate and covers the bottom electrode, and at least part of the top electrode is located above the piezoelectric layer; the excitation electrode is located on the upper surface of the substrate, a distance exists between the excitation electrode and the bottom electrode, the piezoelectric layer is provided with an opening part, and the top electrode is electrically connected with the excitation electrode through the opening part; the excitation electrode is used for receiving an excitation signal and applying the excitation signal to the top electrode, so that an electric field is formed between the top electrode and the bottom electrode to excite the piezoelectric layer to emit an ultrasonic signal, and the bottom electrode is used for receiving an ultrasonic detection signal generated between the top electrode and the bottom electrode when the returned ultrasonic signal acts on the piezoelectric layer. The performance of the ultrasonic transducer in the scheme is good.

The utility model relates to the technical field of road and bridge detection, in particular to an improved pavement crack depth measurement device for road and bridge detection, which comprises a frame, a mounting plate is fixed on the surface of the frame, a measuring instrument is fixed at the top of the mounting plate, self-locking universal wheels are fixed at the bottom of the frame, and the self-locking universal wheels are fixed at the bottom of the frame. A multidirectional adjusting mechanism is mounted at the bottom of the mounting plate, a bidirectional adjusting mechanism is arranged on the surface of the multidirectional adjusting mechanism, an independent adjusting mechanism is arranged on the surface of the bidirectional adjusting mechanism, a transducer is arranged on the surface of the independent adjusting mechanism, and a controller is fixed on the surface of the mounting plate; the multi-direction adjusting mechanism comprises an extending block, the extending block is fixed to the bottom of the mounting plate, and an electric push rod is fixed to the surface of the extending block. High-precision measurement of the crack depth is achieved through cooperative work of the multi-directional adjusting mechanism, the bidirectional adjusting mechanism and the independent adjusting mechanism, and the problems that a transducer of a traditional device is inconvenient to adjust, and the device needs to be moved frequently are solved.

An audio device is provided. The audio device comprises a controller and an acoustic transducer. The controller is configured to receive an input audio signal. The controller is further configured to generate, via a loudness detector, a loudness level of a first portion of the input audio signal. The controller is further configured to identify a compression curve of a plurality of compression curves corresponding to a user volume setting. The controller is further configured to adjust, via an audio compressor, a second portion of the input audio signal based on the loudness level and the compression curve to generate an output audio signal. The loudness level is determined according to LUFS model.

The invention relates to the technical field of aero-engine nondestructive testing, and discloses a method for detecting defects and thickness of a surface coating of an aero-engine blade. The invention designs a novel acoustic impedance sensor special for a blade coating, the novel acoustic impedance sensor comprises a plurality of independently controlled transduction units, each transduction unit has multi-band detection capability, main resonant frequencies of different transduction units are configured in a differentiated manner, and during detection, the novel acoustic impedance sensor is coupled to the surface of a blade; the material state is reversely deduced by measuring the energy absorption spectrum of broadband sound waves in the coating, and the blade surface coating defect and thickness detection is achieved.

The present disclosure is of a bone conduction microphone. The bone conduction microphone comprises of a laminated structure and a base structure. The laminated structure is formed by a vibration unit and an acoustic transducer unit. The base structure is configured to load the laminated structure. At least one side of the laminated structure is physically connected to the base structure. The base structure vibrates based on an external vibration signal, the vibration unit deforms in response to the vibration of the base structure, and the acoustic transducer unit generates an electrical signal based on the deformation of the vibration unit. A resonant frequency of the bone conduction microphone is within a range of 2.5 kHz-4.5 KHz.

The invention provides a short bolt axial stress detection method and device based on electromagnetic ultrasonic resonance, and relates to the technical field of industrial fastener stress detection. The method comprises the following steps: determining a preset period and frequency of an excitation signal according to material characteristics of a to-be-measured short bolt, and calibrating resonant frequency and stress to obtain a calibration curve; classifying the lengths of the short bolts to be measured to obtain bolts with known original lengths and in-service bolts with unknown original lengths; based on the determined preset period and frequency, first-order resonant frequency corresponding to the bolt with the known original length is obtained through an electromagnetic ultrasonic transducer and a single-wave resonance method; based on the determined preset period and frequency, first-order resonant frequency corresponding to the in-service bolt with the unknown original length is obtained through an electromagnetic ultrasonic transducer and a double-wave resonance method; and calculating the axial stress of the corresponding short bolt to be measured according to the calibration curve and the first-order resonant frequency. The problems that in the prior art, the energy conversion efficiency is low, and the short bolt detection effect is poor are solved.

The invention relates to an ultrasonic fluid metering precision improving method and related equipment, and the method comprises the steps: exciting a first ultrasonic transducer through an excitation wave sequence, enabling a second ultrasonic transducer to work, obtaining a received digital signal corresponding to the excitation wave sequence, and calculating the signal-to-noise ratio of the received digital signal; wherein the excitation wave sequence is a combination of a main wave and a self-damping wave, and the signal-to-noise ratio is a ratio of a peak-to-peak value of a receiving signal area to a peak-to-peak value of a noise area; judging whether the signal-to-noise ratio is greater than a signal-to-noise ratio threshold value or not, if not, adjusting the occupation time of the high and low levels of the self-damping waves, and executing the excitation work again according to the adjusted excitation wave sequence until the actual signal-to-noise ratio is greater than the signal-to-noise ratio threshold value; and determining the corresponding excitation wave sequence when the actual signal-to-noise ratio is greater than the signal-to-noise ratio threshold as a target excitation wave sequence, and exciting the ultrasonic transducer to work according to the target excitation wave sequence so as to execute metering operation. According to the method, the measurement precision is remarkably improved while the hardware cost is not increased.

The invention discloses a cable length self-adaptive bolt axial force measurement method, and relates to the technical field of bolt axial force measurement, and a system comprises a target ultrasonic transducer, a measurement terminal and an upper computer, the target ultrasonic transducer comprises an ultrasonic transduction sheet used for transmitting and receiving ultrasonic waves, a temperature measuring resistor used for sensing the temperature of a target bolt to be measured, and a ceramic resonance sheet used for enhancing and amplifying ultrasonic signals; the measurement terminal performs time-sharing execution by switching the connection combination of each core wire in the target three-core cable: measuring the resistance of the target three-core cable to obtain cable length data; measuring the loop resistance including the temperature measuring resistor to obtain current bolt temperature data; the ultrasonic transduction piece is excited with low energy, and returned echo signals are collected to obtain ultrasonic data; and the upper computer obtains the current axial force value of the target to-be-measured bolt according to the cable length data, the current bolt temperature data and the ultrasonic data. By implementing the technical scheme, the effect of improving the measurement precision and efficiency is achieved.

A system and method for determining fluid quality or change in quality by training machine learning algorithms using ultrasound Fast Fourier Transform (FFT) signatures. The system includes one or more ultrasonic transducers embedded inside or outside of a pipe, piping, or vessel that allows a fluid to flow past or between the ultrasound transducers. The transducer's acoustic energy creates ultrasound pressure waves and localized heat due to acoustic cavitation. The cavitation creates bubbles that collapse creating ultrasound sonic energy in the time domain. Unique sonic time-domain signatures, distinctively associated with the characteristics of the fluids, are converted to FFTs to produce unique, well-defined frequency response signatures. Machine learning algorithms are used to identify, measure, and classify the unique frequency response signatures associated with a wide range of fluids.

A loudspeaker includes a housing having a plurality of walls that together define an acoustic cavity. An electro-acoustic transducer is mounted to a front wall of the housing, and an axis of motion of the electro-acoustic transducer is offset from a centroid of the front wall. The loudspeaker is configured to be stacked with another loudspeaker having the same configuration in a first configuration such that the stacked loudspeakers radiate acoustic energy to produce an omnidirectional radiation pattern; and the loudspeaker is configured to be stacked with the other loudspeaker in a second configuration such that the stacked loudspeakers radiate acoustic energy to produce a cardioid radiation pattern. The loudspeaker includes a keying feature that does not interlock and thereby prevent stacking when the loudspeaker is in a first orientation relative to the other loudspeaker, and that interlocks to allow stacking when the loudspeaker is in a second orientation relative to the other loudspeaker.

The invention discloses a multichannel ultrasonic transducer phased array driving method based on direct memory access. The method comprises a waveform data buffer length determination step, a data path construction step, a phase parameter calculation step, a waveform data synthesis step and a DMA driving step. An independent DMA channel is configured for each GPIO port or each group of GPIO ports corresponding to the transducer array by utilizing the DMA characteristic of a universal microcontroller, and buffer data is transmitted to the output data registers of the GPIO ports automatically and periodically by DMA hardware, so that multi-channel driving signals with accurate frequency and controllable phases are generated in parallel under the condition that CPU (Central Processing Unit) intervention is not needed. According to the invention, high-precision time sequence control comparable with an FPGA (Field Programmable Gate Array) scheme is realized with extremely low hardware cost and CPU (Central Processing Unit) resource occupation, the problem of time sequence jitter of an existing MCU (Microprogrammed Control Unit) scheme is solved, and the method has high stability, high efficiency and excellent expandability.

The invention discloses a vortex ultrasonic transducer, an acousto-optic coaxial modulation method and an analogue simulation method, and relates to the technical field of acousto-optic modulation.The method comprises the steps that a focused vortex sound field is generated through the vortex ultrasonic transducer with a center perforated hole, sound beams and light beams are coaxially propagated in the same direction, the sound field is used for regulating and controlling medium refractive index distribution, and the sound field is used for generating a focused vortex sound field; and light beam focusing spiral propagation and scattering suppression are realized. A model is constructed through analogue simulation, and the regulation and control effect of the sound field on the light beams is analyzed. According to the invention, coaxial modulation of the vortex sound fields with different topological charges on the light beams is realized, and a new path is provided for research of an acousto-optic regulation and control technology.

The invention relates to the technical field of semiconductors, in particular to an ultrasonic chip and an ultrasonic module. The ultrasonic chip comprises a circuit layer, a piezoelectric layer and an electrode layer; the circuit layer comprises a substrate, an on-chip circuit of an ultrasonic transmitting circuit is arranged in the substrate, a first bonding pad, a second bonding pad and a first electrode are arranged on the substrate, and the electrode layer comprises a second electrode; the first electrode, the second electrode and the piezoelectric layer are used for forming an ultrasonic transducer; the on-chip circuit is used for generating an electric signal and transmitting the electric signal to the first bonding pad, the first bonding pad is used for transmitting the electric signal to an off-chip circuit of the ultrasonic transmitting circuit, and the off-chip circuit is used for generating an excitation signal according to the electric signal and transmitting the excitation signal to the second bonding pad; the second bonding pad is used for transmitting an excitation signal to the second electrode so as to drive the ultrasonic transducer to emit ultrasonic waves, and the on-chip circuit is located in an area outside an ultrasonic area. According to the embodiment of the invention, the integration level of the ultrasonic chip can be improved.

An ultrasonic spindle, comprising a spindle body (100), a spindle core (200), an ultrasonic wave generation assembly (300), a mounting assembly (400) and a wireless sensing module (500), wherein the spindle body (100) is provided with a gas intake hole (120), the ultrasonic wave generation assembly (300) comprises a transducer (310), a first cooling channel (301) is defined between the mounting assembly (400) and the outer wall of the transducer (310), and the gas intake hole (120) is used for introducing a cooling gas. The cooling gas can enter the first cooling channel to cool the transducer. The ultrasonic spindle has a simple overall structure, and can prevent vibration energy transmission instability caused by an excessive temperature rise of the transducer, which affects the efficiency of electric energy transmission, thereby ensuring the working reliability of the spindle, and improving the working efficiency of the ultrasonic spindle.

Various implementations include approaches for device control and / or sound source selection in audio devices. In some implementations, an audio device includes: an electro-acoustic transducer for providing an audio output; a set of microphones for detecting ambient sounds; and a processor coupled with the electro-acoustic transducer and the set of microphones, the processor configured to: evaluate microphone signals from the set of microphones to identify classes of sound sources in the ambient sounds; and adjust output of at least one class of the ambient sounds relative to another class of ambient sounds based on a user input.

Systems and methods for implementing operation-specific impedance matching for enhancing sensitivity of an ultrasound system are described. To enhance sensitivity while using a transducer element for transmission and reception, a transducer module's architecture provides operation-specific impedance matching. Operation-specific impedance matching means that different impedances are provided for mitigating mismatch loss during transmission and reception. The impedance provided for reception can be associated with separate signal path with a smaller amount of attenuation compared to the impedance provided for transmission. In this way, the architecture enhances sensitivity of the ultrasound system by reducing an amount of attenuation experienced during reception compared to other ultrasound systems that utilize a same impedance for impedance matching during transmission and reception. With enhanced sensitivity, the ultrasound system can utilize higher frequencies and / or broader bandwidths to provide high-resolution images at farther imaging depths while meeting power-intensity guidelines.

The invention relates to the technical field of ultrasonic detection, in particular to a cable aluminum sheath defect grading detection method based on multi-frequency guided waves, which comprises the following steps: determining propagation characteristics of each guided wave mode according to a frequency dispersion curve, and determining excitation frequency for detecting a main mode based on the propagation characteristics; arranging and installing a transducer array on the cable aluminum sheath; according to the coarse screening main modal frequency, low-frequency guided waves are emitted, guided wave echo signals are collected, and low-frequency guided wave coarse screening is carried out to determine a suspected defect interval; and transmitting ultrasonic guided waves to the suspected defect interval according to the fine screening main modal frequency, accurately positioning the suspected defect interval, determining a comprehensive score through multi-feature weighting calculation, and determining a defect grade according to the comprehensive score. Low-frequency guided wave coarse screening is combined with wavelet transform and entropy verification, a suspected defect interval can be quickly locked, high-frequency fine screening extracts multi-dimensional defect features through variational mode decomposition, and accurate positioning of defect positions and scientific judgment of grades are achieved.