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Fast computation of far-field pulse-echo PSF of arbitrary arrays for large sparse 2-D ultrasound array design

ULTRASONICS 2018年 84卷 63-73页

作者： Li, Zhaohui Chi, Cheng Peking Univ Dept Elect 5 Yiheyuan Rd Beijing 100871 Peoples R China

Large wideband two-dimensional (2-D) arrays are essential for high-resolution three-dimensional (3-D) ultrasound imaging. Since the tremendous element number of a full sampled large 2-D array is not affordable in any practical 3-D ultrasound imaging system, it is necessary to reduce the element number through sparse 2-D array design. sparse array design requires that both the positions and weights of the array elements should be arbitrarily alterable. Hence a proper evaluation tool that can deal with arbitrary array is integral to optimizing the array structure and apodization function. It is known that pulse-echo point spread function (PSF) has been a common tool used to evaluate the performance of wideband arrays in ultrasound imaging all along, which also plays an important role in wideband ultrasound simulations. However, so far the conventional ultrasound simulation tools can only calculate pulse-echo PSF of arbitrary wideband arrays in the time domain because of the existence of nonuniform nodes in the spatial impulse response expressions, which obstructs their application of FFT to do fast computation of the time-domain convolutions. As a result, ultra-high time consumption of pulse-echo PSF computation of a large arbitrary wideband array hampers it to be taken as the evaluation tool by any stochastic optimization methods which need massive iterations in designing large sparse 2-D arrays. This paper aims to make available the pulse-echo PSF tool in designing large sparse 2-D arrays by proposing a fast computation method of far-field pulse-echo PSFs of arbitrary wideband arrays. In the paper, fast computation of wideband spatial impulse responses of a 2-D array is first realized in frequency domain by employing the nonuniform fast Fourier transform (NUFFT), under the point source assumption in far-field. On the basis of that, fast computation of time-domain convolutions is made possible by using FFT. In addition, a short inverse FFT (IFFT) is applied in recove

关键词： sparse array design Fast computation Nonuniform FFT (NUFFT) 2-D ultrasound array Point spread function (PSF)

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Two-Dimensional DOA Estimation for Coprime Planar arrays: From array Structure design to Dimensionality-Reduction Root MUSIC Algorithm

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SENSORS 2025年第5期25卷 1456-1456页

作者： Shi, Yunhe Zhang, Xiaofei Han, Shengxinlai Nanjing Univ Aeronaut & Astronaut Coll Elect & Informat Engn Nanjing 211106 Peoples R China

This paper proposes a novel sparse array design and an efficient algorithm for two-dimensional direction-of-arrival (2D-DOA) estimation. By analyzing the hole distribution in coprime arrays and introducing supplementary elements, we design a Complementary Coprime Planar array (CCPA) that strategically fills key holes in the virtual array. This design enhances the array's continuous Degrees Of Freedom (DOFs) and virtual aperture, achieving improved performance in 2D-DOA estimation with fewer physical elements. The virtualization of the array further increases the available DOFs, while the hole-filling strategy ensures better spatial coverage and continuity. On the algorithmic side, we introduce a dimensionality-reduction root MUSIC algorithm tailored for uniform planar arrays after virtualization. By decomposing the two-dimensional spectral peak search into two one-dimensional polynomial root-finding problems, the proposed method significantly reduces computational complexity while maintaining high estimation accuracy. This approach effectively mitigates the challenges of 2D peak search, making it computationally efficient without sacrificing precision. Extensive simulations demonstrate the advantages of the proposed array and algorithm, including higher DOFs, reduced complexity, and superior estimation performance compared to existing methods. These results validate the effectiveness of the proposed framework in advancing sparse array design and signal processing for 2D-DOA estimation.

关键词： sparse array design 2-D DOA estimation coprime planar array array signal processing degrees of freedom (DOFs)

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A framework for the performance evaluation of reconfigurable ultrasonic sparse array networks

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STRUCTURAL HEALTH MONITORING-AN INTERNATIONAL JOURNAL 2025年

作者： Niu, Xudong Croxford, Anthony J. Drinkwater, Bruce W. Todd, Michael D. Univ Bristol Sch Elect Elect & Mech Engn Bristol England Univ Calif San Diego Dept Struct Engn 9500 Gilman Dr 0085 La Jolla CA 92093 USA

Autonomous monitoring strategies are becoming an increasingly popular application modality due to their adaptable deployment and reconfigurability. Motivated by low-cost robotic swarms conveying ultrasonic transducers that are maneuverable into arrays for pipe inspections, this paper aims to develop an initial framework for predicting such an array's performance and understanding the effects of target defect scattering properties and array topology parameters on that performance. Assuming uniformly omnidirectional transducers, we first develop a predictive spatial probability of detection (POD) model that depends on target defect scattering and distance and verify it against experiment. We then synthesize these single-transducer models into arrays and derive global POD performance metrics that are parameterized by defect scattering properties (via the single transducer model) and array topology (geometric arrangement and transducer pitch). We perform a performance evaluation in the case of a highly directional scatterer (e.g., a crack) over the global parameter space to make suggestions about array design.

关键词： sparse array design reconfigurable arrays model-assisted probability of detection guided waves array detection performance

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Venc design and Velocity Estimation for Phase Contrast MRI

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IEEE TRANSACTIONS ON MEDICAL IMAGING 2022年第12期41卷 3712-3724页

作者： Zhao, Shen Ahmad, Rizwan Potter, Lee C. Ohio State Univ Dept Elect & Comp Engn Columbus OH 43210 USA Ohio State Univ Dept Biomed Engn Columbus OH 43210 USA

In phase-contrast magnetic resonance imaging (PC-MRI), spin velocity contributes to the phase measured at each voxel. Therefore, estimating velocity from potentially wrapped phase measurements is the task of solving a system of noisy congruence equations. We propose Phase Recovery from Multiple Wrapped Measurements (PRoM) as a fast, approximate maximum likelihood estimator of velocity frommulti-coildatawith possible amplitude attenuation due to dephasing. The estimator can recover the fullest possible extent of unambiguous velocities, which can greatly exceed twice the highest venc. The estimator uses all pairwise phase differences and the inherent correlations among them to minimize the estimation error. Correlations are directly estimated frommulti-coil data without requiring knowledge of coil sensitivity maps, dephasing factors, or the actual per-voxel signal-to-noise ratio. Derivation of the estimator yields explicit probabilities of unwrapping errors and the probability distribution for the velocity estimate;this, in turn, allows for optimized design of the phase-encoded acquisition. These probabilities are also incorporated into spatial post-processing to further mitigate wrapping errors. Simulation, phantom, and in vivo results for three-point PC-MRI acquisitions validate the benefits of reduced estimation error, increased recovered velocity range, optimized acquisition, and fast computation. A phantom study at 1.5T demonstrates 48.5% decrease in root mean squared error using PRoM with post- processing versus a conventional "dual-venc" technique. Simulation and 3T in vivo results likewise demonstrate the proposed benefits. Index Terms-

关键词： Phase-contrast MRI dual-venc phase unwrapping congruence equations sparse array design

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Multi-Tier Structured array for Sensing Pilot design in Integrated Sensing and Communication 13

Multi-Tier Structured Array for Sensing Pilot Design in Inte...

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13rd IEEE Sensor array and Multichannel Signal Processing Workshop (SAM)

作者： Ren, Jiaying Tsai, Shawn Mediatek USA Inc Adv Commun Technol Commun Syst Design San Diego CA 92128 USA

ISBN: (纸本)9798350344820;9798350344813

In this paper, we explore the use of large-scale sparse arrays for pilot placement in pilot-based sensing within integrated sensing and communication (ISAC) systems. Unlike conventional regular pilot placement method, sparse placement offers a significant reduction in overhead while maintaining high sensing performance. We present a novel large-scale sparse array construction method by introducing a multi-tier array structure. Using the proposed method, the design of large-scale sparse arrays can be simplified into several smaller-sized array design problems, significantly reducing computational complexity and storage requirements. Numerical examples demonstrate the effectiveness of the proposed method for low-overhead sensing pilot placement design, which is applicable in future 6G applications.

关键词： Integrated sensing and communication (ISAC) pilot design sparse array design orthogonal frequency division multiplexing (OFDM) 5G new radio 6G

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OPTIMUM CONFIGURATIONS OF sparse SUBarray BEAMFORMERS

OPTIMUM CONFIGURATIONS OF SPARSE SUBARRAY BEAMFORMERS

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IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)

作者： Deligiannis, Anastasios Amin, Moeness Fabrizio, Giuseppe Lambotharan, Sangarapillai Loughborough Univ Technol Wolfson Sch Mech & Elect Engn Loughborough LE11 3TU Leics England Villanova Univ Ctr Adv Commun Villanova PA 19085 USA Def Sci & Technol Grp Edinburgh Edinburgh SA 5111 Australia

ISBN: (纸本)9781538646588

The problem of optimum distribution of the available spatial degrees of freedom among two sparse antenna subarray beamfomers in shared aperture receiver is investigated. The two subarrays, forming a full array, co-exist on the same platform and could perform separate RF sensing and communications tasks. The sparsity and cardinality of the subarray configurations are joint optimization variables which considerably affect the output signal-to-interference plus noise ratios (SINR) of the two beamformer outputs. A minimum output SINR figure value is imposed to guarantee minimum performance. We solve this problem by utilizing Taylor series approximation to reformulate the initial non-convex problem to a convex one. Simulation results validate the effectiveness of the proposed method.

关键词： Adaptive beamforming sparse array design SINR optimization multiple sources

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Extended Cantor arrays with Hole-Free Fourth-Order Difference Co-arrays 53

Extended Cantor Arrays with Hole-Free Fourth-Order Differenc...

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IEEE International Symposium on Circuits and Systems (IEEE ISCAS)

作者： Yang, Zixiang Shen, Qing Liu, Wei Eldar, Yonina C. Cui, Wei Beijing Inst Technol Sch Informat & Elect Beijing 100081 Peoples R China Univ Sheffield Dept Elect & Elect Engn Sheffield S1 3JD S Yorkshire England Weizmann Inst Sci Fac Math & Comp Sci Rehovot Israel

ISBN: (纸本)9781728192017

We present extended Cantor arrays based on fourth-order difference co-arrays (E-FO-Cantor). These arrays result from extending the recently proposed fractal arrays to fourth-order difference co-arrays, and lead to fourth-order difference co-arrays that are hole-free. The set of sensor positions of the E-FO-Cantor is expressed in a simple and recursive form. The proposed Cantor arrays lead to O(N-2 log2 3) approximate to O(N-3.17) degrees of freedom compared to O(N-2) that can be achieved by existing sparse arrays with the hole-free property. Compared with other sparse arrays with the hole-free property in their fourth-order co-arrays, the proposed Cantor arrays provide a longer uniform linear array with more virtual sensors, leading to better DOA estimation performance.

关键词： sparse array design difference co-array fourth-order cumulants Cantor arrays direction of arrival estimation

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Optimum sparse array Configuration for Mismatched DOA on Moving Platforms

Optimum Sparse Array Configuration for Mismatched DOA on Mov...

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IEEE Radar Conference (RadarConf)

作者： Qin, Guodong Amin, Moeness G. Xidian Univ Sch Elect Engn Xian 710071 Shaanxi Peoples R China Villanova Univ Ctr Adv Commun Villanova PA 19085 USA

ISBN: (纸本)9781728189420

sparse arrays on a moving platform can efficiently expand the numbers of achievable degrees of freedom (DOFs) and consecutive lags, improving direction-of-arrival (DOA) estimation. This property has been recently used for the case of environment-independent structured sparse array configurations, such as those defined by nested and co-prime arrays. In this paper, we consider environment-dependent sparse arrays (EDSAs) design for mismatched DOA using Cramer-Rao bound (CRB) as the metric of optimality. The CRB is derived for multiple sources with angle biases. Two optimization metrics are considered, and solved by enumerations, to provide the optimum arrays. Simulation results are presented to validate the effectiveness of the proposed EDSA design.

关键词： sparse array moving platform sparse array design Cramer-Rao bound mismatched DOA

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Removing grating lobes in sparse sensor arrays with a nonlinear approach 23

Removing grating lobes in sparse sensor arrays with a nonlin...

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2015 23rd Signal Processing and Communications Applications Conference, SIU 2015

作者： Epçaçan, Erdal Çiloʇlu, Tolga Candan, Çaʇatay Mehmetcik, Erdal Elektrik Elektronik Mühendisliʇi Bölümü ODTÜ Ankara Turkey SST ASELSAN Ankara Turkey

ISBN: (纸本)9781467373869

Two of the most important criteria for a sensor array beam-pattern are beamwidth and side-lobe level. A narrower beamwidth means a better angular resolution and well separation of close sources. The beamwidth of a sensor array is directly proportional to array aperture, the beamwidth gets narrower as array aperture increases. However, increase in array aperture means increase in number of used sensors due to Nyquist spatial rate and this means increase in cost and computational load. Therefore, sparse arrays which violate Nyquist spatial rate are used. To cancel grating lobes occurred due to violation of Nyquist rate a weight optimization is implemented. In this paper, an approach which does not need weight optimization for grating lobe cancellation is presented. This method is inspired from nonlinear apodization (windowing) method. The necessary information to cancel grating lobes is obtained from a sub-array contained in the sparse array and this sub-array obeys Nyquist spatial rate. © 2015 IEEE.

关键词： nonlinear apodization sparse array design

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OPTIMUM CONFIGURATIONS OF sparse SUBarray BEAMFORMERS

OPTIMUM CONFIGURATIONS OF SPARSE SUBARRAY BEAMFORMERS

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IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Anastasios Deligiannis Moeness Amin Giuseppe Fabrizio Sangarapillai Lambotharan Wolfson School of Mechanical and Electrical Engineering Loughborough University Leicestershire UK LE11 3TU Center for Advanced Communications Villanova University Villanova PA 19085 USA Defence Science and Technology Group Edinburgh SA 5111 Australia

ISBN: (纸本)9781538646595

关键词： Adaptive beamforming sparse array design SINR optimization multiple sources Adaptive Beam forming optimal distribution subarray SINR configurations base number Taylor series Degree of freedom

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