94 results about "Pulse echo" patented technology

The invention relates to the technical field of optical signal processing and analysis, and particularly provides a submarine optical fiber vibration event detection method based on credibility weighting, and the method comprises the steps: obtaining an optical pulse echo matrix according to a received signal, and carrying out the decomposition of the signal through a low-rank and sparse decomposition model. A credibility coefficient is introduced to measure the reliability of the data, an optimization model is established, and the credibility coefficient is set to be a tide credibility coefficient or a natural disaster credibility coefficient according to the marine environment. Solving the optimization model to obtain a sparse item estimation matrix corresponding to the sparse item; and detecting a natural disaster event and a vibration event in the received signal according to the sparse term estimation matrix. According to the method, reliability evaluation of the signals can be dynamically adjusted according to different marine environments, noise and real vibration events are effectively distinguished, high robustness is kept in the complex and multi-interference marine environment, the method is not prone to being affected by interference sources, and event detection precision and accuracy are good.

The invention discloses a multi-medium three-dimensional flaw detection system based on ultrasonic pulse echoes. The multi-medium three-dimensional flaw detection system comprises a synchronous data acquisition module, a temperature compensation module, a multi-physical field simulation optimization module, a signal processing module and a three-dimensional imaging and output module, the synchronous data acquisition module scans an object, records coordinates and synchronously transmits and receives ultrasonic echoes; the temperature compensation module calculates real-time sound velocity according to the water temperature, the real-time sound velocity is used by the multi-physics field simulation module, and the multi-physics field simulation module simulates sound wave propagation and generates a defect-free theoretical waveform as a reference by combining intrinsic parameters of an object and sound wave propagation parameters; the signal processing module carries out processing and feature extraction on actually measured echoes, and compares the actually measured echoes with a reference to identify defect signals; and the three-dimensional imaging module associates the signals with the coordinates, a three-dimensional model is generated by adopting slice reconstruction and a compressed sensing algorithm, and defects are visualized, so that the precision, the efficiency and the environmental adaptability of three-dimensional flaw detection can be improved.

The invention discloses a material grain size distribution deep learning prediction method based on multi-mode space signal coding, which comprises the following steps: firstly, collecting ultrasonic characteristic signals based on a pulse echo method, collecting space distribution signals as a single-point grain characterization characteristic set by using elliptical distribution by taking a collection point as a center, preprocessing the collection signals to extract characteristics, and carrying out multi-mode space signal coding; feature compression extraction is carried out through a detection model by using a compressed sensing network, material grain size distribution and detection point material thickness are predicted by using a full-connection network, and finally a mean value and a variance of grain size distribution are obtained through comprehensive calculation of detection point prediction results in an elliptical region by using a space fusion method. According to the method, high-precision prediction and high-efficiency calculation of grain size distribution of the metal material are realized, an intermediate network of model training is expected to be used for transfer learning of characterization tasks of other materials, and many problems of a traditional method and an existing data driving method in the aspect of grain size measurement are solved.

The invention relates to the field of photoelectric detection and the technical field of simulation testing, and provides a laser short pulse echo simulation method, system and device for detection tracking. Comprising the following steps: acquiring spatial azimuth coordinates of a plurality of detectors and spatial azimuth coordinates of a laser galvanometer; according to the spatial azimuth coordinates of the detector and the spatial azimuth coordinates of the laser galvanometer, the spatial azimuth coordinates of the detector are converted into a local coordinate system with the laser galvanometer as the center, and the coordinates of the detector are obtained; calculating the azimuth deflection angle of the laser galvanometer according to the coordinates of the detector; galvanometer driving current parameters are calculated according to the azimuth deflection angle of the laser galvanometer; a step-by-step sequential circuit is adopted, a galvanometer driving current parameter is taken as a reference, and laser galvanometers are driven to deflect in sequence, so that laser pulses are captured by a plurality of detectors. According to the invention, through space coordinate dynamic solution and galvanometer accurate control, time division multiplexing of a single laser source to multiple detectors can be realized, and the resource utilization rate is obviously improved.

The invention discloses a method for designing and manufacturing a flexible ultrasonic transducer of a sparse array, and relates to the technical field of transducer manufacturing, a sparse model taking array element number-imaging quality-cost as a target is constructed, and a genetic algorithm is utilized to carry out non-uniform array element arrangement optimization; positive and negative electrodes are manufactured by adopting a microelectronic printing technology, an S-shaped negative electrode loop is designed to reduce crosstalk, PDMS is spin-coated in a layered manner to realize light and thin packaging, and acoustic impedance matching and bendability are improved in combination with a flexible backing material; the method comprises the following steps: simulating a wearing scene, identifying an ultrasonic signal distortion rate, calculating a signal-to-noise ratio and a resolution ratio in real time based on pulse echo data, adjusting an array element driving phase through feedback, and carrying out dynamic calibration optimization. According to the flexible ultrasonic transducer, the imaging performance and reliability are remarkably improved while the manufacturing cost is reduced through sparse, multi-objective optimization and dynamic calibration technologies, and the applicability of the flexible ultrasonic transducer in the fields of wearable medical treatment, industrial detection and the like is expanded.

The invention provides a filling pipeline leakage monitoring and positioning method, device and equipment and a storage medium, and relates to the technical field of pipeline monitoring. The method comprises the following steps: acquiring time-varying data of pressure in a pipeline through a pressure sensing unit, and identifying leakage triggering characteristics; transmitting a pressure pulse wave at the starting end of the pipeline and receiving an echo signal, and calculating a pressure wave propagation speed under the current working condition according to the echo signal; and the arrival time of the pressure waves arriving at the sensors is extracted, and based on the pressure wave propagation speed and the pressure wave arrival time difference, leakage point coordinates are obtained through calculation. According to the method, the leakage characteristics are rapidly identified through real-time pressure collection, the real-time wave velocity under the current working condition is obtained through the active pulse echo technology, and the wave velocity calculation deviation caused by medium characteristic changes is effectively eliminated; and the actually measured wave velocity and the time difference of arrival are combined for calculation, so that error accumulation in long-distance transportation is overcome, and the precision and reliability of pipeline leakage positioning are remarkably improved.

The invention provides a backing structure which can be applied to a transducer. The backing structure includes a first backing layer and a second backing layer. The first backing layer is of a cylindrical conical structure, a first groove is formed in the center of the bottom of the first backing layer, and the first groove is used for containing the piezoelectric layer; the second backing layer is of a columnar structure, a second groove is formed in the center of the bottom of the second backing layer, and the first backing layer is stacked at the bottom of the second backing layer through the second groove. The acoustic impedance of the backing structure is gradually reduced in a gradient change manner from the bottom of the first backing layer to the top of the second backing layer; the two backing layers are both used for absorbing sound waves transmitted backwards by the piezoelectric layer, and the laminated surfaces of the two backing layers are used for promoting absorption of the sound waves transmitted backwards by the piezoelectric layer. Through the double-cone angle design of the backing layer and the acoustic impedance design of gradient change, the attenuation of sound waves in the backing layer can be improved, so that the thickness vibration mode of the transducer is prominent, the working frequency band is widened, and the signal-to-noise ratio of pulse echo signals is enhanced.

The invention discloses an ISAR radar multi-target echo simulation method and system, and relates to the technical field of radar imaging. The method comprises the following steps: S1, constructing a radar multi-target imaging simulation scene; s2, determining a discrete sampling time sequence of single radar pulse echo sampling according to a radar multi-target imaging simulation scene; s3, establishing an echo model of a plurality of scattering points of the single target according to the emission signal model and the echo sampling time, and generating certain echo data of each scattering point of the single target; s4, traversing the remaining targets according to the step S3, and generating single pulse echo data of all the targets; s5, repeating the steps S2 to S4, and generating target echo data of all pulses during imaging; and S6, synthesizing an ISAR radar multi-target echo matrix according to the target echo data of all pulses in the imaging period. According to the method, echo data with multi-target characteristics can be reflected, and verification implementation of an ISAR multi-target imaging algorithm is facilitated.

An acoustic logging system includes a first transducer in contact with or in close proximity to a sound barrier configured to emit a beam of acoustic energy according to a first mode of operation or a second mode of operation. The system also includes one or more second transducers in contact with or in close proximity to the sound barrier, positioned axially away from the first transducer, configured to receive acoustic energy from a wellbore environment responsive to the beam. The first mode of operation is a transmit-receive mode of operation where the beam is steerable to interact with one or more wellbore components at a first angle and the second mode of operation is a pulse echo mode of operation where the beam interacts with the one or more wellbore components at a second angle different from the first angle.

The application provides a multi-domain extremely narrow pulse radar echo target fusion recognition method based on scattering center matching degree constraint and structural feature auxiliary constraint, constructs an end-to-end classification model for multi-frequency and multi-polarization fusion recognition of an extremely narrow pulse radar echo, can perform feature extraction on input multi-frequency and multi-polarization extremely narrow pulse radar echoes and fusion of frequency dimension and polarization dimension information, and then directly recognizes the fusion features, realizes end-to-end fusion recognition integration, adopts deep learning technology based on feature level fusion, can more fully utilize feature information contained in samples, makes the model make more accurate and stable decisions in the classification task. The method fully mines the correlation between multi-frequency and multi-polarization information, fuses the frequency dimension and polarization dimension information mined, utilizes rich scattering information of multi-frequency and multi-polarization extremely narrow pulse radar echoes, and achieves a relatively ideal target recognition effect.

The present invention relates to a method for measuring wet gas two-phase flow, comprising the following steps: building a measurement system: arranging a differential pressure transmitter and an ultrasonic transducer in sequence along a flow direction; building a pulse transceiver circuit; respectively collecting the differential pressure transmitter and conditioned ultrasonic signals; obtaining the thickness of a liquid film at the bottom of a pipeline and the velocity of a disturbance wave of the bottom liquid film based on the obtained conditioned ultrasonic signal based on the ultrasonic pulse echo thickness measurement principle; calculating the flow pressure drop according to an average differential pressure value and a distance between two pressure tapping ports; conducting wet gas experiments under different gas and liquid flow rates, measuring the above three parameters corresponding to each working condition, and establishing functional relationships between the three parameters and the gas phase apparent flow velocity and the liquid phase apparent flow velocity; performing wet gas two-phase flow measurement online, and solving the established functional relationships using the Newton iteration method to obtain the gas phase apparent flow velocity and the liquid phase apparent flow velocity under the current working condition.

The present invention provides an echo signal acquisition system and a lidar, which relate to the technical field of lidar. The system includes: a signal conversion module, a sampling module, and an analog gater. The sampling module is connected between the signal conversion module and the analog gater. The signal conversion module is used to convert the laser pulse echo signal into a voltage pulse signal. The sampling module includes a plurality of sampling units, and the plurality of sampling units are used to sequentially sample each pulse signal in the voltage pulse signal and transmit the sampling point information of each sampled pulse signal to the analog gater. The analog gater is used to output the sampling point information of the pulse signal one by one. Among them, the sampling point information includes the level information of the pulse signal at the sampling moment. The present invention meets the system's requirement for extracting the pulse signal information in the pulse echo signal, reduces the system's requirement for the ADC sampling frequency, reduces the system power consumption, and reduces the system overhead.

The present invention provides a method for simulating laser pulse echoes from jungle targets based on KD tree acceleration, comprising the following steps: Step S1: constructing a physical model of a tree, comprising a trunk and a crown; Step S2: constructing a laser scattering model of the tree; Step S3: constructing a KD tree structure encompassing the jungle and background environment; Step S4: sampling the laser beam emitted by a laser radar (LiDAR), generating a photon beam based on its spatial energy distribution, and performing wavefront segmentation; Step S5: calculating the interaction between each photon in the photon beam generated in Step S4 and the KD tree structure generated in Step S3 to determine whether the photon hits the trunk or crown of the tree in the KD tree structure constructed in Step S3. Step S6: calculating the scattering events of the photons along the path; and Step S7: calculating the laser radar pulse echo based on the interaction between the photon beam and the KD tree structure obtained in Step S5. The present invention has the advantages of wide applicability and ease of use.

The application relates to the technical field of radar signal processing, and discloses a time-frequency domain combined pulse compression processing method for long-pulse high-resolution wind measurement, which comprises the following steps: long-pulse echo data is acquired and subjected to local time-frequency block processing; a theoretical track of a candidate distance unit in a time-frequency plane is constructed according to a propagation time delay; track time-frequency coefficients are extracted, and a frequency domain consistency factor, a local time-frequency energy focusing factor and a Doppler consistency factor are calculated; combined compression weights are generated; the amplitude of a time domain matched filter output is adjusted and the phase information is kept; combined pulse compression output is obtained; and Doppler spectrum estimation is carried out to obtain radial wind speed information. According to the application, the long-pulse echo data is subjected to local time-frequency block processing, and a theoretical track is constructed, so that the frequency domain consistency factor and the local time-frequency energy focusing factor are calculated, thereby reducing distance sidelobe leakage and improving distance resolution capability.

This invention discloses a clutter false alarm suppression method based on multi-feature fusion, comprising: acquiring radar echo signals and performing pulse compression processing to obtain time-domain echo data; performing clutter suppression and coherent accumulation on the time-domain echo data to obtain a range-Doppler matrix; performing constant false alarm detection on the range-Doppler matrix to obtain several potential target points; extracting the multi-pulse echo signals and unsuppressed frequency domain signals corresponding to the potential target points from the time-domain echo data, extracting the corresponding clutter-suppressed frequency domain signals from the range-Doppler matrix, and constructing multi-dimensional features for each potential target point based on the extracted signals; inputting the multi-dimensional features into a pre-trained classifier, determining whether the potential target point is a target or false alarm clutter based on the output results, and outputting the final target point trace. This invention effectively suppresses clutter false alarms in complex environments and improves radar detection reliability through multi-dimensional feature fusion and secondary decision-making by the classifier.

The invention discloses a method for detecting an offshore wind driven generator by a maritime radar, which comprises the following steps of: 1, starting the maritime radar and preheating the maritime radar, and starting scanning by an antenna; 2, during antenna scanning, recording N pulse echo powers of a given distance gate in a certain direction in a coherence interval; 3, periodically detecting and analyzing non-stationary signals of the time sequence; 4, obtaining a periodic index through the periodic detection analysis in the step 3; 5, the periodic indexes are judged; 6, when the periodic index is larger than or equal to a preset threshold value, the target in the specific distance door is judged to be the offshore wind turbine; according to the method, the power time sequence data is acquired through the single and multiple scanning speed modes of the antenna, the characteristic indexes are comprehensively extracted in combination with multiple periodic detection algorithms, the wind driven generator target can be accurately identified, and the method has the characteristics of improving the detection accuracy, reducing the radar false alarm rate, guaranteeing the marine navigation safety and being wide in applicability.

Method of operating a detection radar and associated detection radar. The present invention relates to a method of operating a target detection radar (10) using a first radar mode and a second radar mode corresponding to Doppler modes. The method comprises the implementation of several repetitions of a signal transmission / reception step (110), each Nth repetition of said step (110) comprising the following substeps: + generation (111) of two consecutive pulses associated with the different radar modes and different transmission directions; + transmission (112) of the pulses in different frequency bands, the pulses associated with the different radar modes being emitted using different slopes of the chirps used to emit them; + reception (113) in a common time window of the pulse echoes. Figure for the abstract: Figure 4

The application discloses a kind of high-resolution ultra-wide imaging method and system based on intra-pulse multi-beam, wherein the method comprises: each sub-pulse echo signal is filtered to obtain each sub-mapping band echo signal;Each sub-mapping band echo signal is processed to obtain the output signal of each receiving channel;According to the time-varying weighting coefficient of each receiving channel and the output signal of each receiving channel, the signal after DBF processing of each receiving channel is obtained;Each receiving channel DBF processed signal is processed to obtain each sub-mapping band signal;Each sub-mapping band signal is two-dimensionally focused to obtain the SAR image of each sub-mapping band region;The SAR image of each sub-mapping band region is spliced in range direction, and high-resolution ultra-wide SAR image is obtained.The application effectively solves the problem that traditional spaceborne SAR system is difficult to realize high-resolution and ultra-wide imaging simultaneously.

An intravascular ultrasound transducer assembly for monitoring stiffness of a vessel wall. The assembly comprises a catheter shaft sized and shaped for insertion inside a vessel having a vessel wall and one or more intravascular devices integrated on the catheter shaft. The one or more intravascular devices are configured to monitor at least one of i) at least one anatomic structure of the vessel wall in response to a pulse wave being launched on the vessel wall so that a pulse wave velocity is determined, by operating in a pulse echo mode to track the at least one anatomic structure, and ii) signals indicative of an ambient pressure of the ultrasound transducer assembly, wherein the ambient is defined by a balloon encapsulating one of the one or more intravascular devices. The pulse wave velocity and the ambient pressure are related to, i.e., proportional to, the stiffness of the vessel wall.

Phase-based methods can be used for one or more of acquisition, storage, or subsequent analysis (e.g., A-scan reconstruction or full focus method imaging) to support acoustic inspection. For example, binarization or other quantization techniques can be used to compress the amount of data associated with time series signal acquisition. A representation of phase information from the time series signals can be generated, e.g., by processing the binarized time series signals or otherwise quantized time series signals. As an illustrative example, using the representation of phase information, one or more A-scan reconstructions can be performed using phase summing techniques, e.g., for pulse echo A-scan inspection, or TFM imaging techniques can be used. In such phase summing methods, the time series representations of phase data can be summed, e.g., where each time series can be delayed (or phase-rotated) by an appropriate delay value, and then aggregated.

The invention provides a laser radar target echo generation device, and relates to the technical field of laser radar target characteristic digital simulation and high repetition frequency narrow pulse laser echo regeneration. According to the device, through a laser radar body target echo simulation system, a body target simulation model matched with a body target is screened out from a typical target model library; performing multi-channel optical characteristic simulation on the body target by using the laser radar, and generating body target echo simulation data of the laser radar on the typical target under different rendezvous conditions; the laser radar body target echo generation module is used for carrying out pulse echo detection of which the half bandwidth is in a nanosecond level according to the body target echo simulation data; a pulse current signal is converted into an electric pulse signal in an undistorted manner, the electric pulse signal is converted into an optical pulse signal in an undistorted manner, and the optical pulse power in a single pulse is modulated in real time. The problems that the target echo generated by the existing laser radar point target echo generation device is simple in characteristic and the real characteristic of the echo is difficult to simulate are solved.

The present invention discloses a navigation radar multiple reflection false target identification technology based on arithmetic sequence extraction. The technology utilizes the rule that false echoes formed by multiple reflections appear at equal intervals along the same azimuth and their energy decays successively. First, a group of equally spaced extreme points is extracted for each pulse echo. Extreme points distributed according to the arithmetic sequence rule are extracted using a distance sampling rate δr as a stepping interval. Then, "distance-azimuth-equally spaced value" clustering and "group number-class number" clustering are performed in sequence. Finally, multiple reflection false echoes are identified and marked, thereby eliminating or reducing their impact on the navigation radar's detection of real surface targets. The present invention can effectively identify and mark false targets formed by multiple reflection echoes in navigation radar echoes, avoiding false alarms and missed detections caused by false echoes on surface target observations. Furthermore, ship scale information is extracted from the echoes, facilitating subsequent surface target identification and tracking.

The invention discloses a radar altimeter data processing method and device and a storage medium, and relates to the technical field of radar altimeter data processing. The method comprises the following steps: carrying out processing and target detection on all echo signals to obtain potential target points; dividing M pulse echo data in one frame into a plurality of data segments with different accumulation lengths; for each potential target point, calculating coherent accumulation energy of the potential target point in each data segment; according to the change rule of coherent accumulation energy of the potential target points among the data segments, incoherent interference target points are discriminated and filtered out; sorting the residual target points after filtering according to energy, and selecting Q target points with the highest energy for tracking; and comparing the energy of each target tracking chain in the historical frame, and taking the distance value corresponding to the target tracking chain with the highest energy as the final output value of the radar altimeter. According to the invention, data jump is greatly suppressed from a data source, and the problem of lack of capability of suppressing power supply fluctuation and electromagnetic interference is solved.

The application provides an underwater single-photon lidar target reconstruction method based on modal fusion and collaborative variational imaging optimization, comprising the following steps: reconstructing the original echo data of the underwater single-photon lidar into a superimposed photon number sequence corresponding to X*Y pixel points, wherein the superimposed photon number sequence corresponding to each pixel point is generated by performing photon number superposition based on a time bin grid on the multiple laser pulse echo signals received at its position, and the number M of laser pulses for performing photon number superposition on each pixel point is the same; performing depth-reflectivity estimation based on modal fusion on the superimposed photon number sequence of each pixel point to obtain a depth map and a reflectivity map of the underwater target; and optimizing the depth map and the reflectivity map of the underwater target based on a collaborative variational imaging optimization strategy. Using the method provided by the application, a high-quality reconstructed image of the underwater target can be quickly obtained.

Method of operating a detection radar following at least one observation operating mode using chirp slopes and associated detection radar. The present invention relates to a method of operating a target detection radar following at least one observation operating mode of a portion of the radar's environment, the method comprising the implementation of several repetitions of a signal transmission / reception step, each Nth repetition of said step comprising the following substeps: - generation of a sequence of consecutive pulses, each pulse of the sequence being associated with a respective observation zone, each observation zone being different, - transmission of the pulses in different frequency bands, the pulses associated with each observation zone being emitted using different chirp slopes used to transmit them.and - reception of pulse echoes within a common time window. Figure for the abbreviation: Figure 5,

A system for non-destructive defect detection includes a calibration block and at least two phased array probes configured to transmit and receive pulsed echo signals. The calibration block includes a base metal having a first surface opposite a second surface, a corrosion resistant alloy coupled to the first surface of the calibration block, and a manual weld overlay extending from the first surface of the calibration block to a second surface of the calibration block. A method for non-destructive defect detection includes providing a system for non-destructive defect detection and calibrating at least two phased array probes of the system for non-destructive defect detection to form at least two calibrated phased array probes.

The present invention provides a method, device, and apparatus for integrated processing of moving target detection and imaging by a spaceborne radar, relating to the field of microwave radar technology. The method comprises: acquiring multi-channel broadband multi-pulse echo signals from the spaceborne radar, dividing the multi-channel broadband multi-pulse echo signals into multiple groups of narrowband short-time echo signals; performing adaptive clutter suppression processing on each group of narrowband short-time echo signals to obtain a clutter suppression residual map corresponding to each group of narrowband short-time echo signals; performing non-coherent detection on each group of clutter suppression residual maps to determine at least one potential moving target detected by the spaceborne radar, and generating a high-resolution image of each potential moving target based on the clutter suppression residual map.

This invention discloses a method for resisting dense false target interference based on complex empirical mode decomposition, comprising the following steps: S1: detecting false targets; S2: performing CEMD decomposition on each group of pulse echoes in the false targets to obtain several intrinsic mode functions (IMFs); S3: solving for the centroid IMF based on the IMFs and the phase projection direction. ZX The projections in all directions are averaged, and the centroid IMF is calculated. ZX S4: Recover the intrinsic mode function (IMF); S5: Solve the centroid IMF of each pulse echo. ZX The intrinsic mode function (IMF) components with high correlation to the transmitted signal are retained, while those with poor correlation are removed, resulting in a multi-pulse signal after interference suppression. The purpose of this invention is to suppress the dense false target deception interference suffered by traditional radar systems.

The invention relates to the technical field of ground clutter suppression, in particular to a security radar ground clutter suppression method, system and device and a storage medium, and the method comprises the following steps: receiving a pulse echo signal, inputting the pulse echo signal into a dynamically updated time-varying clutter model, and obtaining a self-adaptive suppression result; performing two-dimensional fast Fourier transform and constant false alarm detection on the self-adaptive suppression result to obtain a constant false alarm detection result; and by calculating the mean square error of signal points in the constant false alarm detection result and evaluating the signal quality, determining ground clutter diffusion points in the constant false alarm detection result and filtering the ground clutter diffusion points to obtain a pulse echo signal after clutter suppression. According to the method, ground object static clutters can be effectively inhibited, the detection capability of target signals with the target speed close to zero frequency and Doppler frequency is reserved and enhanced, residual clutter diffusion points can be further inhibited, and the overall false alarm is reduced.

The invention discloses an ultrasonic online detection system for continuously winding a glass reinforced plastic pipe, which belongs to the technical field of pipeline nondestructive testing and integrates a multi-channel ultrasonic detection module, an ultrasonic probe, a water tank, a water storage tank, a water circulation filtering system, a water tank position adjusting mechanism, a marking machine, an electric control system and an upper computer. A multi-channel ultrasonic detection module and a low-frequency large-size ultrasonic probe are adopted, and a pulse echo technology and a dynamic parameter adjustment technology are combined, so that different wall thicknesses are adapted, and missing detection is avoided; by means of a position adjusting mechanism, a flexible water tank and a gate tracking technology, pipeline jumping and unevenness are compensated in a self-adaptive mode; a multi-factor coupling sound velocity calibration module is innovatively provided, the influence of high temperature, wall thickness and sand inclusion distribution on the sound velocity is corrected in real time, and the defect positioning precision is remarkably improved. The system has the functions of real-time imaging, defect alarm and statistics, and realizes efficient and accurate on-line detection of the internal defects of the pipeline.