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Superior perturbation inversion strategy based on Markov random field incorporating measurement matrix optimization in linear array photoacoustic tomography

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INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER 2025年 240卷

作者： Zhao, Ying Niu, Zhitian Gao, Baohai He, Mingjian Ren, Yatao Qi, Hong Harbin Inst Technol Sch Energy Sci & Engn Harbin 150001 Peoples R China Minist Ind & Informat Technol Key Lab Aerosp Thermophys Harbin 150001 Peoples R China China Jiliang Univ Coll Metrol Measurement & Instrument Hangzhou 310018 Peoples R China

Photoacoustic tomography technology, which combines the advantages of deep tissue penetration of ultrasound imaging and high contrast of optical imaging, has emerged as a prominent research area in biomedicine. However, the accuracy of its imaging is inherently constrained by factors such as detection angle and energy attenuation in the medium, presenting ongoing challenges in enhancing efficiency. In response to these challenges, we propose a superior perturbation inversion strategy based on the Markov random field incorporating measurement matrix optimization coupled with linear-Extremum-guided interpolation (PMMLI). This model leverages spatiotemporal information captured during the linear array detection process to enhance signal continuity. Moreover, the iterative results are guided toward a superior pathway by optimizing the measurement matrix and incorporating the Markov Random Field prior information of diagonal neighbors as a supplementary perturbation criterion in reconstruction. Through imaging of semi-transparent media containing vascular-shaped absorbers, our results demonstrate that PMMLI yields smoother background images and more detailed vascular structures compared to alternative methods (the conjugate gradient method, the piecewise cubic Hermite interpolation method, and linear-Extremum-guided interpolation method). The Structural Similarity Index Measure (0.999) and Peak Signal Noise Ratio (59.997 dB) of the PMMLI model are three times and two times higher than those of other methods (about 0.3 and 20 dB), respectively. The Root Mean Square Error is only 0.094 %, which is two orders of magnitude lower compared to other technologies. Notably, even in scenarios where up to 30 % measurement error is introduced, PMMLI maintains the ability to discern main vascular structures, underscoring its robustness. This research lays a foundation for advancing the accuracy and reliability of photoacoustic tomography, showcasing the potential of PMMLI in addressi

关键词： Photoacoustic tomography linear array Interpolation Measurement matrix Markov random field Perturbation inversion

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A 3.45 GHz linear array antenna based on Wilkinson power divider structure

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AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS 2025年 189卷

作者： Xiao, Weibing Fan, Kuangang Zhou, Fazhu Zhu, Jizan Li, Shuliang Jiangxi Univ Sci & Technol Kejia St 1958 Ganzhou 341000 Jiangxi Peoples R China Jiangxi Prov Key Lab Maglev Rail Transit Equipment Kejia St 1958 Ganzhou 341000 Jiangxi Peoples R China

In this paper, Aiming at the problems of high delay, high density, and low transmission rate of 5G mobile communication in a maglev train, a linear array antenna with 5G parallel feed of 3.45 GHz is proposed to solve the problem of low gain of 5G antenna in n78 band. The antenna is based on a non-traditional Wilkinson power splitter structure to improve antenna gain. The power divider is finally extended to eight. Antenna design on low-cost FR4 material dielectric substrate while improving antenna gain, with a dielectric constant of 4.4 and a thickness of 1.6 mm. Firstly, the original size of the patch is calculated based on Matlab software and optimized by HFSS electromagnetic software simulation. Finally, the results are relatively matched by comparing the experiment with the simulation. The antenna was sequentially improved from 3.2 dB to 5.6 dB, 8.2 dB, and 9.3 dB, which are 75%, 45.42%, and 11.41% higher than the previous level of the antenna of its design, respectively, and finally 6.1 dB higher. After simulation and testing, it can be seen that the antenna has the advantages of high gain, low sidelobe, low cost, and strong directivity.

关键词： linear array Wilkinson's power splitter Low sidelobe High gain

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Group Sparsity-Based Wideband 3-D Localization Using a Distributed linear array Network

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IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS 2025年第2期61卷 5454-5460页

作者： Wu, Hantian Shen, Qing Zhou, Junwei Liu, Wei Li, Wei Cui, Wei Beijing Inst Technol Sch Informat & Elect Beijing 100081 Peoples R China China Acad Space Technol Inst Telecommun & Nav Satellites Haidian 100094 Peoples R China Hong Kong Polytech Univ Dept Elect & Elect Engn Kowloon Hong Kong Peoples R China

In this article, wideband 3-D source localization utilizing only 1-D angle measurements based on a general distributed linear array (in lieu of planar array) network is studied. Instead of fusing the independent directions of arrival estimated by individual subarrays to form the final source location, a group sparsity-based localization method is proposed to exploit the information acquired by all receivers jointly with the corresponding closed-form Cram & eacute;r-Rao bound for 3-D localization derived. Simulation results demonstrate that improved performance and robustness is achieved by our proposed method.

关键词： Location awareness Three-dimensional displays Vectors Wideband Focusing Direction-of-arrival estimation Aerospace and electronic systems Receivers Maximum likelihood estimation Discrete Fourier transforms 3-D localization Cram & eacute r-Rao bound (CRB) distributed array network group sparsity (GS) linear array wideband

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High-Frequency linear array (20 MHz) Based on Lead-Free BCTZ Crystal

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IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL 2024年第1期71卷 27-37页

作者： Bantignies, Claire Rouffaud, Remi Buse, Gabriel Veber, Philippe Cabane, Hugues Borta-Boyon, Ana Thi, Mai Pham Mauchamp, Pascal Lejeune, A. Maglione, Mario Colin, Laurent Bale, Antoine Flesch, Martin Levassort, Franck VERMON SA F-37038 Tours France Univ Tours CNRS GREMAN UMR 7347 INSA CVL F-37200 Tours France West Univ Timisoara Inst Adv Environm Res ICAM Timisoara 300223 Romania Univ Lyon CNRS Universitei Lyon F-69622 Villeurbanne France EZUS Cristal Innov F-73800 Sainte Heilene Du Lac France Thales Res & Technol F-91120 Palaiseau France Univ Bordeaux ICMCB Bordeaux INP CNRSUMR 5026 F-33600 Pessac France

Centimeter-sized BaTiO3 -based crystals grown by top-seeded solution growth from the BaTiO3 -CaTiO3 -BaZrO3 system were used to process a high-frequency (HF) lead-free linear array. Piezoelectric plates with (110)pc cut within 1 degrees accuracy were used to manufacture two 1-3 piezo-composites with thicknesses of 270 and 78 mu m for resonant frequencies in air of 10 and 30 MHz, respectively. The electromechanical characterization of the BCTZ crystal plates and the 10 MHz piezocomposite yielded thickness coupling factors of 40% and 50%, respectively. We quantified the electromechanical performance of the second piezocomposite (30 MHz) according to the reduction in the pillar sizes during the fabrication process. The dimensions of the piezocomposite at 30 MHz were sufficient for a 128-element array with a 70 mu m element pitch and a 1.5 mm elevation aperture. The transducer stack (backing, matching layers, lens and electrical components) was tuned with the characteristics of the lead-free materials to deliver optimal bandwidth and sensitivity. The probe was connected to a real-time HF 128-channel echographic system for acoustic characterization (electroacoustic response, radiation pattern) and to acquire high-resolution in vivo images of human skin. The center frequency of the experimental probe was 20 MHz, and the fractional bandwidth at -6 dB was 41%. Skin images were compared against those obtained with a lead-based 20-MHz commercial imaging probe. Despite significant differences in sensitivity between elements, in vivo images obtained with a BCTZ-based probe convincingly demonstrated the potential of integrating this piezoelectric material in an imaging probe.

关键词： High-frequency (HF) ultrasonic transducer lead-free material linear array piezoelectricity ultrasonic imaging

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A Novel Near-Field Calibration Method for linear array Based on Plane Wave Expansion

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 2024年第11期72卷 8173-8183页

作者： Tang, Yuanhua Wang, Zhengpeng Fan, Wei Chen, Xiaoming Loh, Tian-Hong Luo, Zhiming Gao, Steven Beihang Univ Dept Elect & Informat Engn Beijing 100191 Peoples R China Southeast Univ Sch Informat Sci & Engn Natl Mobile Commun Res Lab Nanjing 210096 Peoples R China Jiaotong Univ Sch Informat & Commun Engn Xian 710049 Peoples R China Natl Phys Lab Engn Electromagnet & Electrochem Technol Dept Teddington England Chinese Univ Hong Kong Dept Elect Engn Hong Kong Peoples R China

This article presents a novel near-field calibration method for linear arrays based on plane wave expansion. The proposed method enables the calibration of an antenna under test (AUT) with a compact measurement distance and a probe scanning aperture as small as 1/10 of the AUT aperture. The calibration measurement can be implemented by moving a probe antenna in a sparse grid along a line segment parallel to the AUT and collecting the AUT array element response. In the proposed method, an ideal virtual linear array is employed to model the AUT, where the virtual AUT possesses the same configuration as the AUT and consists of array elements with consistent radiation characteristics. The virtual AUT is determined by minimizing the difference between the response of the virtual and actual AUT, where the virtual AUT response can be constructed based on plane wave expansion. The least square (LS) method is applied to minimize the difference, while an optimization algorithm is employed to solve the radiation characteristics and the initial excitations of the virtual AUT. In the validation measurement, a nonuniform linear array (NULA) is calibrated in the near field using the proposed method with a probe scanning aperture of only 1/10 of the AUT aperture and a measurement distance of 4.33 wavelengths at 2.6 GHz. Based on the obtained results, +/- 0.41 dB in amplitude and +/- 4.7 degrees in phase calibration accuracy are achieved, respectively, demonstrating the effectiveness of the proposed method.

关键词： Probes Calibration Antenna measurements Phased arrays linear antenna arrays Antenna radiation patterns Phase measurement linear array near-field calibration optimization algorithm plane wave expansion

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linear array synthesis based on artificial neural network agent model with fast Fourier transform 16

Linear array synthesis based on artificial neural network ag...

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16th International Conference on Microwave and Millimeter Wave Technology (ICMMT)

作者： Li, Aowei Liu, Jiahao Zhang, Xin Liu, Zhe Li, Foxiang Nanchang Univ Sch Informat Engn Nanchang 330029 Jiangxi Peoples R China Minist Educ Key Lab Numer Simulat Large Scale Complex Syst Beijing Peoples R China

ISBN: (纸本)9798350389968

This paper introduces a new array synthesis method based on back propagation (BP) neural network agent model with a training set quickly generated by fast Fourier transform. Moreover, it can be conveniently generalized to array models on different scenarios. A test example for synthesizing uniformly spaced linear array with non-uniform excitations is conducted. Synthesis results prove the effectiveness and superiority of the proposed method.

关键词： array synthesis linear array artificial neural networks fast Fourier transform

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Design of Clustered Phased arrays by Means of an Innovative Power Pattern Matching-Driven Method-The linear array Case

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 2024年第5期72卷 4185-4197页

作者： Benoni, Arianna Poli, Lorenzo Rocca, Paolo Massa, Andrea Univ Trento ELEDIA Res Ctr Dept Civil Environm & Mech Engn DICAM ELEDIA UniTN I-38123 Trento Italy Univ Trento CNIT Res Unit I-38123 Trento Italy Xidian Univ ELEDIA Res Ctr ELEDIA XIDIAN Xian 710071 Shaanxi Peoples R China Univ Elect Sci & Technol China ELEDIA Res Ctr Sch Elect Sci & Engn ELEDIA UESTC UESTC Chengdu 611731 Peoples R China Tsinghua Univ ELEDIA Res Ctr ELEDIA TSINGHUA Beijing 100084 Peoples R China Tel Aviv Univ Sch Elect Engn IL-69978 Tel Aviv Israel

The design of subarrayed phased arrays (PAs) with subarray-only amplitude and phase controls that afford arbitrary-shaped power patterns matching reference ones is addressed. Such a synthesis problem is formulated in the power pattern domain, and an innovative complex-excitations clustering method, which is based on the decomposition of the reference power pattern in a number of elementary patterns equal to the array elements, is presented. A set of representative results is reported to illustrate the features of the proposed approach as well as to assess its effectiveness in comparison with benchmark results from the state-of-the-art (SoA) excitation matching (EM)-based clustering methods.

关键词： Phased arrays Pattern matching linear antenna arrays Clustering algorithms Europe Design methodology Transmission line measurements clustered array iterative projection method (IPM) k-means algorithm linear array phased array (PA) power pattern matching (PM)

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A wide angle phase-frequency scanning linear array composed of leaky-wave antenna

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2024年第4期66卷 e34120-e34120页

作者： Xu, Junqing Xia, Yulong Zhu, Qi Univ Sci & Technol China Chinese Acad Sci Key Lab Electromagnet Space Informat Hefei 230027 Peoples R China

Here, a wide-angle phase-frequency scanning linear array composed of leaky-wave antennas (LWAs) is proposed. The unit cell of the proposed LWA element consists of microstrip lines and grounded vias. By increasing the scanning rate based on theoretical analysis, wide scanning range with low gain fluctuation of the LWA element is achieved. For gain enhancement, the LWAs are arranged along their length to form a linear array. A method combining theoretical derivation and numerical calculation is used to obtain a high efficiency and low sidelobe level (SLL) of the array. To verify the design method, a 1x4 $1\times 4$ linear LWA array is designed, fabricated and measured. The main beam of the LWA array can scan from -60 degrees $-60<^>\circ $ to 50 degrees $50<^>\circ $ in frequency band of 9.3-11.6 GHz with gain fluctuation less than 2 dB and SLL less than -9 $-9$ dB. The measured results are in good agreement with the simulated results.

关键词： composite right/left-handed line frequency-dependent leaky-wave antennas linear array

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Wearable 256-Element MUX-Based linear array Transducer for Monitoring of Deep Abdominal Muscles

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APPLIED SCIENCES-BASEL 2025年第7期15卷 3600-3600页

作者： Speicher, Daniel Gruen, Tobias Weber, Steffen Hewener, Holger Klesy, Stephan Rumanus, Schabo Strohm, Hannah Stamm, Oskar Perotti, Luis Tretbar, Steffen H. Fournelle, Marc Fraunhofer IBMT Dept Ultrasound D-66280 Sulzbach Germany PREMA Semicond GmbH D-55129 Mainz Germany Fraunhofer MEVIS D-28359 Bremen Germany Charite Unive Med Berlin Forschungsgrp Geriatrie D-13347 Berlin Germany

Reliable acoustic coupling in a non-handheld mode and reducing the form factor of electronics are specific challenges in making ultrasound wearable. Applications relying on a large field of view (such as tracking of large muscles) induce a need for a large element count to achieve high image quality. In our work, we developed a 256-element linear array for imaging of abdominal muscles with four integrated custom-developed 8:32 multiplexer Integrated Circuits (ICs), allowing the array to be driven by our compact 32 ch electronics. The system is optimized for flexible use in R&D applications and allows adjustable transmit voltages (up to +/-100 V), arbitrary delay patterns, and 12-bit analog-to-digital conversion (ADC) with up to 50 MSPS and wireless (21.6 MBit/s) or USB link. Image metrics (SLL, FWHM) were very similar to a fully populated array driven with a 256 ch system. The contrast allowed imaging of lesions down to 7 cm in the phantom. In a first in-vivo study, we demonstrated reliable acoustic contact even during exercise and were able to visualize deep abdominal muscles such as the TrA. In combination with a muscle tracking algorithm, the change of thickness of the TrA during SSE could be monitored, demonstrating the potential of the approach as biofeedback for physiotherapy training.

关键词： linear array multiplexer wearable ultrasound B-mode plane wave compounding multichannel electronics

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Evaluation of Kaiser Function-Based linear array Performance in Suppressing SLL and Its Experimental Approach

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IEEE ACCESS 2024年 12卷 94712-94732页

作者： Mistialustina, Hartuti Chairunnisa, Achmad Munir, Achmad Inst Teknol Bandung Sch Elect Engn & Informat Radio Telecommun & Microwave Lab Bandung 40132 Indonesia Univ Sangga Buana YPKP Fac Engn Dept Elect Engn Bandung 40124 Indonesia

The power-weighted distribution method is used to satisfy radiation pattern requirements at acertain targeted sidelobe level (SLL) suppression. This article reports a detailed discussion of theoreticaland experimental approaches for the application of the Kaiser function in power-weighted linear arrayprototypes. An exploration of the design and realization of a Kaiser function-based linear array waspresented. Furthermore, performance evaluations were performed for several important factors in theKaiser function-based linear array configuration. The performance evaluations include feeding networkvariations, number of element (N) variations, and inter-element distance (d) variations. The prototype ofKaiser function-based linear array was configured by a serial feeding type on the folded structure of aproximity-coupled feeding network. The Kaiser function parameter,beta, is used to determine the set ofweighting coefficients. In the application of beta value of 2, the SLL suppression is 34.63 dB - 34.78 dBfor simulation result, and 27.96 dB - 33.47 dB for measurement result. A performance comparison with auniform linear array and a Chebyshev function-based linear array in an equal configuration is also *** Kaiser function utilization as a weighting coefficient in a linear array design shows a significant increaseof 20 dB - 30 dB in SLL suppression compared to the one with a uniform distribution, and 5 dB - 8 dBin SLL suppression compared to the Chebyshev function-based linear array. The implementation of thepower-weighted distribution method with Kaiser functions resulted in good results for the development ofmore complex designs with a larger number of antenna array elements.

关键词： Antenna arrays linear antenna arrays Antenna radiation patterns Chebyshev approximation Radar antennas Diffraction array signal processing Kaiser function linear array power weighting radiation pattern sidelobe level (SLL) width of mainlobe (WML)

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