scholarly journals An Industrial B-Mode Phased Array Ultrasonic Imaging Reconstruction Algorithm Based on FRI Sampling

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Guangzhi Dai ◽  
Zhiyong He ◽  
Song Lin
Keyword(s):  
Phased Array ◽  
Simulation Experiment ◽  
Ultrasonic Imaging ◽  
Reconstruction Algorithm ◽  
Imaging Method ◽  
Sampling Point ◽  
Simple Circuit ◽  
Ultrasonic Signals ◽  
Imaging Algorithm ◽  
Imaging Reconstruction

Firstly, a novel FRI sampling model has been proposed according to the characteristics of ultrasonic signals. The model has the advantages such as good stability, strong antinoise ability, simple circuit implementation, and fewer preconditions, compared to the traditional methods. Then, in order to verify the validity of the sampling model, the method is applied to B-type ultrasonic imaging, and a B-type phased array ultrasonic imaging algorithm based on FRI sampling model is proposed. Finally, the algorithm simulation experiment is designed, and the results show that the sampling point required by the proposed FRI sampling model is only 0.1% of the traditional B-type phased array ultrasonic imaging method, and the sampling frequency of the proposed ultrasonic imaging algorithm is only 0.0077% of the traditional B-type ultrasonic imaging method. Additionally, the experiment result indicates that this algorithm is more applicable to phased array ultrasonic imaging than the SOS filter is.

scholarly journals FEA-Based Ultrasonic Focusing Method in Anisotropic Media for Phased Array Systems

2021 ◽  
Vol 11 (19) ◽  
pp. 8888
Author(s):  
Seongin Moon ◽  
To Kang ◽  
Soonwoo Han ◽  
Kyung-Mo Kim ◽  
Hyung-Ha Jin ◽  
...  
Keyword(s):  
Wave Propagation ◽  
Ultrasonic Wave ◽  
Elastic Constants ◽  
Grain Orientation ◽  
Phased Array ◽  
Ultrasonic Imaging ◽  
Anisotropic Media ◽  
Imaging Method ◽  
Ultrasonic Wave Propagation ◽  
Propagation Paths

Traditional ultrasonic imaging methods have a low accuracy in the localization of defects in austenitic welds because the anisotropy and inhomogeneity of the welds cause distortion of the ultrasonic wave propagation paths in anisotropic media. The distribution of the grain orientation in the welds influences the ultrasonic wave velocity and ultrasonic wave propagation paths. To overcome this issue, a finite element analysis (FEA)-based ultrasonic imaging methodology for austenitic welds is proposed in this study. The proposed ultrasonic imaging method uses a wave propagation database to synthetically focus the inter-element signal recorded with a phased array system using a delay-and-sum strategy. The wave propagation database was constructed using FEA considering the grain orientation distribution and the anisotropic elastic constants in the welds. The grain orientation was extracted from a macrograph obtained from a dissimilar metal weld specimen, after which the elastic constants were optimized using FEA with grain orientation information. FEA was performed to calculate a full matrix of time-domain signals for all combinations of the transmitting and receiving elements in the phased array system. The proposed approach was assessed for an FEA-based simulated model embedded in a defect. The simulation results proved that the newly proposed ultrasonic imaging method can be used for defect localization in austenitic welds.

Group sparsity based imaging algorithm for TWRI under wall parameter uncertainties

2016 ◽  
Vol 40 (1) ◽  
pp. 251-260 ◽  
Author(s):  
Yanpeng Sun ◽  
Shi Zhang ◽  
Zhao Cui
Keyword(s):  
High Resolution ◽  
Matching Pursuit ◽  
Multipath Propagation ◽  
Reconstruction Algorithm ◽  
Imaging Method ◽  
Group Sparsity ◽  
Parameter Uncertainties ◽  
Reconstruction Procedure ◽  
Imaging Algorithm ◽  
Imaging Algorithms

Through-the-wall radar imaging (TWRI) applications allow accurate target localization and high-resolution imaging. However, multipath propagation generates challenges to the image reconstruction procedure. With distortions in the received radar signals, traditional imaging algorithms are not able to acquire high-resolution images. The unpredictability of the indoor scattering environment makes this even worse. In this paper, a novel block orthogonal matching pursuit (BOMP)-based group-sparsity reconstruction algorithm combined with particle swarm optimization (PSO) is proposed for reliable scene reconstruction. The proposed imaging algorithm can recover the image of targets by exploiting multipath propagation and simultaneously estimating wall parameters with high accuracy. The effectiveness of the proposed imaging method has been further demonstrated via simulation results.

scholarly journals Group Sparse Basis Pursuit Denoising Reconstruction Algorithm for Polarimetric Through-the-Wall Radar Imaging

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Lele Qu ◽  
Shimiao An ◽  
Tianhong Yang ◽  
Yanpeng Sun
Keyword(s):  
Reconstruction Algorithm ◽  
Spectral Projection ◽  
Radar Imaging ◽  
Basis Pursuit ◽  
Imaging Method ◽  
L1 Norm ◽  
Reconstruction Performance ◽  
Imaging Reconstruction ◽  
Imaging Algorithms

Polarimetric through-the-wall radar imaging (TWRI) system has the enhancing performance in the detection, imaging, and classification of concealed targets behind the wall. We propose a group sparse basis pursuit denoising- (BPDN-) based imaging approach for polarimetric TWRI system in this paper. The proposed imaging method combines the spectral projection gradient L1-norm (SPGL1) algorithm with the nonuniform fast Fourier transform (NUFFT) technique to implement the imaging reconstruction of observed scene. The experimental results have demonstrated that compared to the existing compressive sensing- (CS-) based imaging algorithms, the proposed NUFFT-based SPGL1 algorithm can significantly reduce the required computer memory and achieve the improved imaging reconstruction performance with the high computational efficiency.

Ultrasonic Block Compressed Sensing Imaging Reconstruction Algorithm Based on Wavelet Sparse Representation

2020 ◽  
Vol 16 (3) ◽  
pp. 262-272
Author(s):  
Guangzhi Dai ◽  
Zhiyong He ◽  
Hongwei Sun
Keyword(s):  
Compressed Sensing ◽  
Sparse Representation ◽  
Linear Array ◽  
Imaging System ◽  
Ultrasonic Imaging ◽  
Large Data ◽  
Reconstruction Algorithm ◽  
Array Transducer ◽  
Total Data ◽  
Block Compressed Sensing

Background: This study is carried out targeting the problem of slow response time and performance degradation of imaging system caused by large data of medical ultrasonic imaging. In view of the advantages of CS, it is applied to medical ultrasonic imaging to solve the above problems. Objective: Under the condition of satisfying the speed of ultrasound imaging, the quality of imaging can be further improved to provide the basis for accurate medical diagnosis. Methods: According to CS theory and the characteristics of the array ultrasonic imaging system, block compressed sensing ultrasonic imaging algorithm is proposed based on wavelet sparse representation. Results: Three kinds of observation matrices have been designed on the basis of the proposed algorithm, which can be selected to reduce the number of the linear array channels and the complexity of the ultrasonic imaging system to some extent. Conclusion: The corresponding simulation program is designed, and the result shows that this algorithm can greatly reduce the total data amount required by imaging and the number of data channels required for linear array transducer to receive data. The imaging effect has been greatly improved compared with that of the spatial frequency domain sparse algorithm.

scholarly journals Ultrasonic Imaging of Thick Carbon Fiber Reinforced Polymers through Pulse-Compression-Based Phased Array

2021 ◽  
Vol 11 (4) ◽  
pp. 1508
Author(s):  
Muhammad Khalid Rizwan ◽  
Stefano Laureti ◽  
Hubert Mooshofer ◽  
Matthias Goldammer ◽  
Marco Ricci
Keyword(s):  
Carbon Fiber ◽  
Pulse Compression ◽  
Phased Array ◽  
Signal To Noise Ratio ◽  
Near Field ◽  
Ultrasonic Imaging ◽  
Fiber Reinforced Polymers ◽  
Fiber Reinforced ◽  
Custom Made ◽  
Carbon Fiber Reinforced

The use of pulse-compression in ultrasonic non-destructive testing has assured, in various applications, a significant improvement in the signal-to-noise ratio. In this work, the technique is combined with linear phased array to improve the sensitivity and resolution in the ultrasonic imaging of highly attenuating and scattering materials. A series of tests were conducted on a 60 mm thick carbon fiber reinforced polymer benchmark sample with known defects using a custom-made pulse-compression-based phased array system. Sector scan and total focusing method images of the sample were obtained with the developed system and were compared with those reconstructed by using a commercial pulse-echo phased array system. While an almost identical sensitivity was found in the near field, the pulse-compression-based system surpassed the standard one in the far-field producing a more accurate imaging of the deepest defects and of the backwall of the sample.

Nonlinear ultrasonic imaging method for closed cracks using subtraction of responses at different external loads

Ultrasonics ◽  
2011 ◽  
Vol 51 (6) ◽  
pp. 661-666 ◽  
Author(s):  
Yoshikazu Ohara ◽  
Satoshi Horinouchi ◽  
Makoto Hashimoto ◽  
Yohei Shintaku ◽  
Kazushi Yamanaka
Keyword(s):  
Ultrasonic Imaging ◽  
Imaging Method ◽  
Nonlinear Ultrasonic ◽  
External Loads

Ultrasonic imaging of stress corrosion crack formed in high temperature pressurized water using subharmonic phased array

2010 ◽  
Author(s):  
Yoshikazu Ohara ◽  
Yohei Shintaku ◽  
Satoshi Horinouchi ◽  
Makoto Hashimoto ◽  
Yuichi Yamaguchi ◽  
...  
Keyword(s):  
High Temperature ◽  
Stress Corrosion ◽  
Stress Corrosion Crack ◽  
Phased Array ◽  
Ultrasonic Imaging ◽  
Pressurized Water
Sign in / Sign up

Export Citation Format

Share Document