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2-D Slicewise Waveform Inversion of Sound Speed and Acoustic Attenuation for ring array Ultrasound Tomography Based on a Block LU Solver

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IEEE TRANSACTIONS ON MEDICAL IMAGING 2024年第8期43卷 2988-3000页

作者： Ali, Rehman Mitcham, Trevor M. Brevett, Thurston Agudo, Oscar Calderon Martinez, Cristina Duran Li, Cuiping Doyley, Marvin M. Duric, Nebojsa Univ Rochester Med Ctr Dept Imaging Sci Rochester NY 14642 USA Stanford Univ Dept Elect Engn Stanford CA 94305 USA FrontWave Imaging Barcelona 08025 Spain Imperial Coll London Dept Earth Sci & Engn London SW7 2AZ England Wayne State Univ Karmanos Canc Inst Detroit MI 48201 USA Delphinus Med Technol Novi MI 48374 USA Univ Rochester Dept Elect & Comp Engn Rochester NY 14627 USA Wayne State Univ Karmanos Canc Inst Detroit MI 48201 USA Univ Rochester Dept Elect & Comp Engn Rochester NY 14642 USA

Ultrasound tomography is an emerging imaging modality that uses the transmission of ultrasound through tissue to reconstruct images of its mechanical properties. Initially, ray-based methods were used to reconstruct these images, but their inability to account for diffraction often resulted in poor resolution. Waveform inversion overcame this limitation, providing high-resolution images of the tissue. Most clinical implementations, often directed at breast cancer imaging, currently rely on a frequency-domain waveform inversion to reduce computation time. For ring arrays, ray tomography was long considered a necessary step prior to waveform inversion in order to avoid cycle skipping. However, in this paper, we demonstrate that frequency-domain waveform inversion can reliably reconstruct high-resolution images of sound speed and attenuation without relying on ray tomography to provide an initial model. We provide a detailed description of our frequency-domain waveform inversion algorithm with open-source code and data that we make publicly available.

关键词： Attenuation Mathematical models Ultrasonic imaging Tomography Image reconstruction Acoustics Frequency-domain analysis Frequency domain waveform inversion tomography ultrasound ring array

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ring array Passive Acoustic Mapping Using Hybrid Heterogeneous Angular Spectrum Method

Ring Array Passive Acoustic Mapping Using Hybrid Heterogeneo...

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IEEE International Ultrasonics Symposium (IUS)

作者： Zhu, Hui Huang, Yiming Jin, Gaofei Cai, Xiran ShanghaiTech Univ Shan Sch Informat Sci & Technol Shanghai 201210 Peoples R China

ISBN: (数字)9781665466578

ISBN: (纸本)9781665466578

Passive acoustic mapping (PAM) using a ring array facilitates high-resolution panoramic monitoring of cavitation activities in human breast. While the heterogeneous angular spectrum method has been developed for fast PAM reconstruction using planar arrays, it is not directly applicable in ring arrays. In this work, we combine the Rayleigh-Sommerfeld diffraction integral and the angular spectrum method for fast panoramic PAM with high resolution in heterogeneous medium. We evaluated the spatial resolution of the hybrid method with ring array in simulated experiments. Bubble clouds localization ability of the proposed method was assessed by imaging 9 tubes containing randomly distributed bubbles in the tumor of a human breast phantom with heterogeneous speed of sound (SoS) and compared with time-domain (TD-) and frequency-domain (FD-) "delay and sum"(DAS) methods. Results show that the proposed method can provide high resolution panoramic PAM images in the heterogeneous human breast phantom with more than 8 times speed-up compared to TD-DAS and FD-DAS algorithms.

关键词： passive acoustic mapping ring array angular spectrum

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A High-Resolution 3D Ultrasound Imaging System Oriented towards a Specific Application in Breast Cancer Detection Based on a 1 x 256 ring array

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MICROMACHINES 2024年第2期15卷 209-209页

作者： Zhang, Junhui Wu, Fei Meng, Fansheng Zhang, Guojun Wang, Renxin Yang, Yuhua Cui, Jiangong He, Changde Jia, Licheng Zhang, Wendong North Univ China State Key Lab Instrumentat Sci & Dynam Measurement Taiyuan 030051 Peoples R China North Univ China Sch Instrument & Elect Natl Key Lab Elect Measurement Technol Taiyuan 030051 Peoples R China

This paper presents the design and development of a high-resolution 3D ultrasound imaging system based on a 1 x 256 piezoelectric ring array, achieving an accuracy of 0.1 mm in both ascending and descending modes. The system achieves an imaging spatial resolution of approximately 0.78 mm. A 256 x 32 cylindrical sensor array and a digital phantom of breast tissue were constructed using the k-Wave toolbox. The signal is acquired layer by layer using 3D acoustic time-domain simulation, resulting in the collection of data from each of the 32 layers. The 1 x 256 ring array moves on a vertical trajectory from the chest wall to the nipple at a constant speed. A data set was collected at intervals of 1.5 mm, resulting in a total of 32 data sets. Surface rendering and volume rendering algorithms were used to reconstruct 3D ultrasound images from the volume data obtained via simulation so that the smallest simulated reconstructed lesion had a diameter of 0.3 mm. The reconstructed three-dimensional image derived from the experimental data exhibits the contour of the breast model along with its internal mass. Reconstructable dimensions can be achieved up to approximately 0.78 mm. The feasibility of applying the system to 3D breast ultrasound imaging has been demonstrated, demonstrating its attributes of resolution, precision, and exceptional efficiency.

关键词： 3D ultrasound imaging system ultrasonic tomography ring array breast imaging high-resolution

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A complementary split-ring array for compact decoupling 2 x 2 circularly polarized antenna

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2021年第4期63卷 1294-1303页

作者： Gao, Di Cao, Zhenxin Quan, Xin Xu, Changzhi Chen, Peng Southeast Univ Sch Informat Sci & Engn State Key Lab Millimeter Waves Nanjing 210096 Peoples R China

In this letter, a complementary split-ring array (CSRA) for decoupling compact (edge-to-edge spacing of 0.078 lambda(0)) 2 x 2 circularly polarized (CP) microstrip antenna is proposed. The CSRA is the ground plane with the etched split-ring array (SRA) which is composed of 12 split-rings. Each element is surrounded by four etched split-rings, and the two adjacent elements share the same etched split-ring between them. The decoupling mechanism of the CSRA is to alter the amplitude and phase of the original coupling field and make the polarization of the adjusted coupling field mismatch with the receiving field. To verify the idea, the 2 x 2 CP antennas with and without CSRA are simulated and measured. The experimental results show that the maximum mutual coupling reduction is 29.6 dB for S-12, 23.6 dB for S-14, and 5.6 dB for S-13. Meanwhile, the impedance bandwidth and radiation characteristics remain almost unchanged. The measured results agree well with the simulated results, which showed new light on application of the proposed CSRA for multiple-input-multiple-output systems.

关键词： split‐ ring array mutual coupling 2 × 2 circularly polarized antenna

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Ultrasound computed tomography image reconstruction with multi-mode aperture matching of ring array

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MEASUREMENT SCIENCE AND TECHNOLOGY 2024年第3期35卷 035409-035409页

作者： Shi, Lifan Wang, Hongliang Huang, Xiao Yuan, Xuting Ding, Qi Zhang, Wendong North Univ China State Key Lab Dynam Measurement Technol Taiyuan Peoples R China

Ultrasound computed tomography (USCT) imaging with a ring array holds significant potential for the inspection of small animals, breast tissue, and industrial components. Despite its promise, current techniques face challenges in terms of image quality. This paper presents a multi-mode aperture matching method for USCT image reconstruction with a ring array, aiming to enhance imaging performance. The proposed method utilizes a full ring transducer to transmit signals with a designated sub-aperture, while the receiving sub-aperture is adjusted based on the reference center element. By altering the transmitting and receiving sub-apertures under different conditions, specific imaging effects can be achieved. Experimental validation was conducted using a hair strand of 0.03 mm diameter placed at both center and eccentric positions within the ring array, in conjunction a breast phantom. Image resolution and contrast were assessed using full width at half maximum and contrast-to-noise ratio metrics. The results identified optimal transmitting and receiving sub-aperture matching modes for imaging the hair strand at various positions, and demonstrated the impact of this method on imaging targets at different positions within the breast phantom. These findings and experimental validations provide significant implications for enhancing imaging performance in USCT with a ring array.

关键词： image quality multi-mode aperture matching ring array USCT

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Research on the Multi-Element Synthetic Aperture Focusing Technique in Breast Ultrasound Imaging, Based on the ring array

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MICROMACHINES 2022年第10期13卷 1753-1753页

作者： Wu, Yang Zhang, Wendong Shao, Xingling Yang, Yuhua Zhang, Tian Lei, Miao Wang, Zhihao Gao, Bizhen Hu, Shumin North Univ China State Key Lab Dynam Measurement Technol Taiyuan 030051 Peoples R China North Univ China Sch Instrument & Elect Natl Key Lab Elect Measurement Technol Taiyuan 030051 Peoples R China

As a widely clinical detection method, ultrasonography (US) has been applied to the diagnosis of breast cancer. In this paper, the multi-element synthetic aperture focusing (M-SAF) is applied to the ring array of breast ultrasonography (US) imaging, which addresses the problem of low imaging quality due to the single active element for each emission and the reception in the synthetic aperture focusing. In order to determine the optimal sub-aperture size, the formula is derived for calculating the internal sound pressure of the ring array with a 200 mm diameter, and the sound pressure distribution is analyzed. The ring array with 1024 elements (1024 ring array) is established in COMSOL Multiphysics 5.6, and the optimal sub-aperture size is 16 elements, according to the sound field beam simulation and the directivity research. Based on the existing experimental conditions, the ring array with 256 elements (256 ring array) is simulated and verified by experiments. The simulation has a spatial resolution evaluation in the k-Wave toolbox, and the experiment uses nylon rope and breast model imaging. The results show that if the sub-aperture size has four elements, the imaging quality is the highest. Specifically, the spatial resolution is the best, and the sound pressure amplitude and signal-to-noise ratio (SNR) are maintained at a high level in the reconstructed image. The optimal sub-aperture theory is verified by the two kinds of ring arrays, which also provide a theoretical basis for the application of the multi-element synthetic aperture focusing technology (M-SAF) in ring arrays.

关键词： ultrasonography breast imaging ring array synthetic aperture multi-element synthetic aperture focusing

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Multielement ring array Based on Minute Size PMUTs for High Acoustic Pressure and Tunable Focus Depth

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SENSORS 2021年第14期21卷 4786页

作者： Ledesma, Eyglis Zamora, Ivan Uranga, Arantxa Barniol, Nuria Univ Autonoma Barcelona Dept Engn Elect Bellaterra 08193 Spain

This paper presents a multielement annular ring ultrasound transducer formed by individual high-frequency PMUTs (17.5 MHz in air and 8.7 MHz in liquid) intended for high-precision axial focalization and high-performance ultrasound imaging. The prototype has five independent multielement rings fabricated by a monolithic process over CMOS, allowing for a very compact and robust design. Crosstalk between rings is under 56 dB, which guarantees an efficient beam focusing on a range between 1.4 mm and 67 mu m. The presented PMUT-on-CMOS annular array with an overall diameter down to 669 mu m achieves an output pressure in liquid of 4.84 kPa/V/mm(2) at 1.5 mm away from the array when the five channels are excited together, which is the largest reported for PMUTs. Pulse-echo experiments towards high-resolution imaging are demonstrated using the central ring as a receiver. With an equivalent diameter of 149 mu m, this central ring provides high receiving sensitivity, 441.6 nV/Pa, higher than that of commercial hydrophones with equivalent size. A 1D ultrasound image using two channels is demonstrated, with maximum received signals of 7 mVpp when a nonintegrated amplifier is used, demonstrating the ultrasound imaging capabilities.

关键词： PMUTs annular array ring array ultrasound AlN ultrasound imaging pulse-echo PMUT-on-CMOS

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Design and Fabrication of a Stacked Three-Phase Piezoelectric Composites ring array Underwater Ultrasound Transducer

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MATERIALS 2021年第20期14卷 5971页

作者： Xia, Lili Wang, Hongwei Huang, Qiguo Beijing Informat Sci & Technol Univ Sch Sci Beijing 100192 Peoples R China

A stacked three-phase piezoelectric composites ring array underwater ultrasound transducer was developed in this paper. The circular structure of three-phase piezoelectric composite with a large open angle was improved based on the 1-3 piezoelectric composites. The structure size of the transducer's sensitive component was designed by using ANSYS simulation software, and the single-ring samples of three-phase piezoelectric composites with different thicknesses were fabricated. Based on the bandwidth broadening theory of multimode coupled vibration, the piezoelectric composite ring-shaped sensitive component was fabricated by the piezoelectric composite curved-surface-forming process. According to the design structure of the transducer, the stacked three-phase piezoelectric composites ring array underwater ultrasound transducer was processed. The experimental results show that the maximum transmission voltage response is 154 dB, the open angle of the horizontal beam reaches 360 & DEG;, and the bandwidth of -3 dB is 86 kHz. The developed transducers achieved a high frequency, broadband, and large open angle to radiate sound waves.

关键词： underwater acoustic transducer three-phase piezocomposites ring array broadband

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Efficient particle collection using concentric optical ring array

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JOURNAL OF OPTICS 2021年第4期23卷

作者： Wang, Lin Cao, Yongyin Zhang, Yanxia Shi, Bojian Li, Hang Feng, Rui Sun, Fangkui Ding, Weiqiang Harbin Inst Technol Inst Adv Photon Sch Phys Harbin Peoples R China

Trapping is the first as well as the most important step in various optical manipulations. However, when the concentration of sample is extremely low, optical trapping cannot be performed efficiently because the samples are usually out of the action radius of the trapping well. In this paper, numerical simulation results are presented to illustrate an active and efficient optical collection mechanism. We propose the optical collection mechanism by using an array of concentric dielectric rings, in which a series of nanoholes are introduced with optimized separations and radius to form trapping centers. When the incident wavelength is tuned in order, the trapped particles will be transferred from an outer ring to its inner neighboring ring, and finally be collected to the center of the rings. The mechanism reported here paves the way for efficient particle collection, and may find potential applications in various optical manipulations.

关键词： optical tweezers or optical manipulation ring array laser trapping

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A Study on ring array Imaging Method for Concealing Weapon Detection

A Study on Ring Array Imaging Method for Concealing Weapon D...

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7th International Conference on Communications, Signal Processing, and Systems (CSPS)

作者： Gui, Shuliang Li, Jin Univ Elect Sci & Technol China Sch Informat & Commun Engn Chengdu 611731 Sichuan Peoples R China

ISBN: (纸本)9789811365041;9789811365034

In this paper, a ring array imaging method for near-filed security screening is proposed for densely populated areas security imaging. With the fixed transceivers, this method can avoid the motion phase error, which is ineluctable in traditional synthetic aperture radar (SAR). Besides, the number of transceivers is less than planar array radar with the same quality of imaging results. The convolution back propagate (CBP) algorithm is adopted to reconstruct image to avoid the phase error, which is created by plane-wave hypothesis for near-field imaging in high-frequency band. Moreover, the simulation results of CBP and other imaging algorithm are described and compared. And the experimental results are shown to verify the performance of this method.

关键词： ring array Near-filed imaging Security screening

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