11 results about "Coded excitation" patented technology

The invention discloses an ultrasonic weak scattering enhancement detection system and method for micro leakage of a liquid pipeline, and relates to the technical field of industrial pipeline state monitoring and nondestructive testing. By performing enhancement processing on a bubble weak scattering signal generated by micro-leakage in the pipeline and inverting bubble parameters, online monitoring, graded early warning and positioning analysis of micro-leakage of the liquid pipeline are realized. The system comprises a clamping type transducer assembly and a control processing unit which are electrically connected, the transducer assembly is mounted on the outer wall of the pipeline; the control processing unit is configured to collect a baseline reference signal and construct a background model; transmitting a coding excitation signal, and driving an ultrasonic transducer assembly to transmit ultrasonic waves; synchronously acquiring ultrasonic echoes or transmission signals; carrying out preprocessing and weak scattering enhancement processing on the original sampling signal; inverting a bubble parameter and a gas content parameter; carrying out leakage judgment, and outputting micro leakage monitoring quantity and graded alarm information; the invention further discloses a method based on the system.

The application discloses a kind of magnetoacoustic electric imaging method, system, equipment, medium and product, it is related to magnetoacoustic electric imaging field, the method comprises: according to the number of array elements of annular array probe Randomly generate multiple sets of space delay coding;Space delay coding is set on the annular array probe, and the corresponding ultrasonic wave of space delay coding is emitted by annular array probe;The delay of each array element is different, and the ultrasonic wave waveform emitted by each array element is identical;While array element emits ultrasonic wave, the magnetoacoustic electric signal excited by space delay coding is collected by electrode, and the ultrasonic wave emission of each set of space delay coding corresponds to the collection of one magnetoacoustic electric signal;According to each set of space delay coding, corresponding acoustic vibration velocity field is simulated and generated;According to the acoustic vibration velocity field corresponding to all space delay coding, system matrix is determined;According to system matrix and magnetoacoustic electric signal, reconstruct conductivity image, realize magnetoacoustic electric imaging, and the application improves spatial resolution and improves imaging effect.

One aspect of the invention relates to method and system for increasing signal-to-noise ratio (SNR) and suppressing range lobe artifacts in ultrasound imaging or sensing, active sonar, LIDAR, and / or radar. The method includes forming a coded excitation waveform with a chip waveform and a binary sequence; transmitting the coded excitation waveform into a medium of interest, and receiving signals generated from the medium of interest responsive to excitation of the coded excitation waveform; and performing pulse compression on the received signals using a decoding filter to increase the SNR and suppress the range lobe artifacts.

The invention discloses a method for improving the color Doppler signal-to-noise ratio of deep peripheral pancreatic vessels, and relates to the technical field of medical ultrasonic imaging. According to the method, the signal penetrating power is enhanced and the original data quality is optimized by combining coding excitation and matched filtering with self-adaptive space composite imaging at the front end, and blood flow signals are intelligently extracted through self-adaptive clutter suppression and a deep learning model in sequence at the rear end and are finally fused and displayed with a B-mode image. According to the method, the problem of extremely low signal-to-noise ratio of deep peripancreatic vessel color Doppler imaging caused by serious signal attenuation and background noise interference is systematically solved. According to the method, the detection capability of deep low-speed blood flow signals can be effectively enhanced within a safety limit value, clearer and more accurate blood flow images are obtained, dependence on experience of an operator is reduced, and the diagnosis reliability is improved.

This invention discloses a high-speed blood flow Doppler measurement method and system for miniaturized ultrasound catheter probes. It employs a high-pulse repetition frequency complementary Golay-coded pulse sequence to replace continuous wave transmission, achieving a distance-dimensional information-discarding equivalent CW effect through extremely high PRF combined with range-gate coherent summation. Pulse compression processing gain is obtained through Golay BPSK encoding excitation. A pulse-by-pulse A / B alternating transmission strategy is used, with each physical pulse independently extracting Doppler samples using a matched filter corresponding to the codeword. Time-division multiplexing of pulse modes enables full-aperture transmission and reception, eliminating TX-RX acoustic leakage. This invention achieves a comprehensive signal-to-noise ratio gain of approximately 31 dB without exceeding the thermal load of traditional CW, restoring clinically usable CW equivalent Doppler spectra on ICE catheters, and can be implemented through firmware upgrades on existing PW Doppler hardware.

The invention discloses an echo-enhanced composite metal layer thickness detection model construction method, which comprises the following steps of S1, constructing a finite element simulation model, adding specific material attributes, and setting corresponding boundary conditions; s2, adding an elastic wave physical field to the simulation model and carrying out grid division; s3, performing research setting on the simulation model, setting an excitation signal and performing signal contrastive analysis, wherein the setting of the excitation signal comprises the steps of generating a binary phase coding sequence, modulating the sequence to a carrier signal, forming a phase coding excitation signal, and applying a time domain window function to the phase coding excitation signal; and S4, calculating the simulation model to obtain a time waveform one-dimensional curve graph. The barker code has a good self-correlation characteristic, the main lobe and side lobe ratio of the 13-bit barker code is maximum, the anti-interference capability is high, effective signals can be distinguished more easily in interference, the detection resolution is high, and recognition is easy.

The invention provides a magnetic flux leakage detection anti-interference method based on coding excitation and synchronous decoding and a related device, and belongs to the technical field of nondestructive testing. The method comprises the steps of obtaining an excitation signal; encoding the excitation signal to obtain a digital encoding sequence; modulating the digital coding sequence to a carrier wave with a set frequency to obtain a coding excitation signal; performing power amplification on the coded excitation signal to obtain a coded excitation signal after power amplification; on the basis of the coded excitation signal after power amplification, magnetizing the to-be-tested piece, and constructing a magnetic field with coding characteristics; acquiring a mixed signal on the surface of the to-be-tested piece; synchronously decoding the mixed signal on the surface of the test piece to be tested and the coding excitation signal to obtain a defect characteristic signal related to the coding excitation signal; and analyzing the defect characteristic signal to obtain a defect detection result of the to-be-tested piece. According to the invention, the problem of poor anti-interference effect of magnetic flux leakage detection is solved.

The application discloses a kind of steel rail fracture monitoring methods based on multivariate coding ultrasonic guided wave technology, first multivariate coding sequence is based on traditional binary coding Barker code and binary orthogonal complementary Golay code, then through series mathematical operation, form a new multivariate excitation coding sequence, through the multivariate coding sequence modulation ultrasonic guided wave single pulse excitation signal, form new coding excitation waveform, monitor steel rail fracture damage by new coding excitation waveform.The multivariate coding excitation ultrasonic guided wave signal proposed in the application combines the advantages of two basic coding methods, increases the flexibility of coding length, improves the signal-to-noise ratio gain and peak sidelobe level of multivariate coding excitation ultrasonic guided wave signal, improves the working efficiency of steel rail fracture monitoring.

The application discloses a grounding resistance measurement method based on zero-point synchronous coding excitation, which comprises generating a coding excitation signal at a preset measurement frequency, applying a measurement excitation to a measured grounding branch by a pressurizing clamp, collecting a response signal by the pressurizing clamp, performing correlation extraction corresponding to a coding sequence on the response signal, obtaining a measurement response amplitude and calculating a grounding resistance measurement value. The coding excitation adopts a coding switching mode synchronized with the zero point of the measurement pressurizing signal, so that the chip state updating occurs at the zero-crossing position of the measurement pressurizing signal, the switching transient state is reduced, and the pressurizing implementation is improved. One chip corresponds to each half carrier cycle, and a data window with at least one complete coding length is used for correlation extraction. Background noise spectrum can be collected before measurement or a coding sequence can be selected according to a preset scene category, so that the measurement accuracy and stability in a strong interference environment are improved. The application is suitable for ordinary single-branch double-clamp grounding resistance measurement, has the advantages of strong anti-interference ability, convenient digital implementation and high measurement precision.

The invention relates to the technical field of process parameter measurement, and discloses a gas-solid two-phase flow measurement method and system based on an array electrostatic sensor, and the method comprises the steps: applying a group of multiphase periodic potentials to an upstream space-time coding modulator, forming a space-time coding excitation field in a pipeline, and carrying out the electrical characteristic modulation of a flowing particle cloud cluster; acquiring a response signal through a downstream synchronous sensing array, and synchronously demodulating the response signal to obtain an in-phase component representing in-phase response and an orthogonal component representing orthogonal response; and calculating to obtain a flow parameter based on the in-phase component and the orthogonal component. The reference signal strictly synchronized with the excitation signal is adopted to perform phase-locked amplification processing on the response signal, so that a weak response component caused by modulation can be extracted from background noise far stronger than the target signal with high selectivity, and the signal-to-noise ratio and the detection sensitivity of the system are greatly improved.