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Numerical and experimental study of circular array to enhance acoustic tweezer-based particle manipulation

ULTRASONICS 2025年 152卷 107647页

作者： Meng, Yuhan Zhang, Jie Hong, Zhenyu Drinkwater, Bruce W. Northwestern Polytech Univ Sch Phys Sci & Technol Xian 710072 Peoples R China Univ Bristol Fac Sci & Engn Bristol BS8 1TR England

Acoustic tweezers enable non-contact, non-invasive manipulation, with promising applications in fields such as biology, micromechanics, and advanced materials. The circular array, commonly used to generate acoustic vortices-an important type of acoustic tweezer-consists of multiple independently addressable elements arranged in a circular configuration. By adjusting the element excitations, the circular array can flexibly control the location of particles. In this study, we employed numerical and experimental methods to analyse the relationship between device geometrical parameters and acoustic field distribution, as well as their impact on particle manipulation. Results from the three-dimensional model indicate that water surface height, array radius, and the material and thickness of the bottom observation layer, significantly influence the acoustic field distribution and, hence trapping performance. Additionally, we used trap stiffness theory to evaluate particle movement capability, and experimentally identified conditions under which trapping may fail, providing theoretical support for improving acoustic tweezer technology.

关键词： circular array Acoustic vortices Particle manipulation Trap stiffness Numerical simulation Acoustic field distribution

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circular array design based on Bayesian Cramer-Rao bound

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MULTIDIMENSIONAL SYSTEMS AND SIGNAL PROCESSING 2020年第1期31卷 317-328页

作者： Behmandpoor, Pourya Haddadi, Farzan Iran Univ Sci & Technol Sch Elect Engn Tehran Iran

In this paper, we consider circular array design in the presence of a far-field or a near-field signal source. The location of the source is introduced to our optimization problem by its probability density function (PDF) as a priori information. We consider Bayesian Cramer-Rao bound as the cost function to be minimized to specify the best locations of the sensors on a circular boundary. In the far-field case, a closed form solution is derived for an arbitrary PDF of the bearing. In the near-field scenario, we divide the design problem into three categories: known source bearing, known source range, and the general case. We present some examples to exhibit the process of array design by the proposed method. Finally, we show the array optimized by the proposed method outperforms arrays with other configurations in source localization.

关键词： circular array array design Bayesian CRB Location estimation Optimization

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circular array with displaced phase reference

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2019年第5期61卷 1240-1243页

作者： Chepala, Anil Fusco, Vincent Queens Univ Belfast Inst Elect Commun & Informat Technol ECIT Belfast BT3 9DT Antrim North Ireland

We describe how the phase reference of a circular array can be relocated from its center to an arbitrary radiating element located on the array while preserving the ability to project a collimated beam that can be steered into any azimuthal direction as with a conventional circular array. The ability to arbitrarily reposition the phase reference of the array makes this suitable for reducing Doppler effects when the array is in motion.

关键词： circular array Doppler phase center

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circular array of Endfire Yagi-Uda Monopoles With a Full 360° Azimuthal Beam Scanning

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 2022年第7期70卷 6042-6047页

作者： Wen, Yubo Qin, Pei-Yuan Wei, Geng-Ming Ziolkowski, Richard W. Univ Technol Sydney UTS Global Big Data Technol Ctr GBDTC Ultimo NSW 2007 Australia

A multiport circular array of endfire Yagi-Uda monopoles with a full beam coverage of the azimuth plane is developed in this communication. The known issue that a vertical monopole antenna on a finite-sized horizontal ground plane radiates an elevated beam is investigated. It is demonstrated that this effect can be mitigated by inserting resonant structures, i.e., slots, into the ground plane to redirect the radiated beam back to the horizontal direction. An endfire monopole-based Yagi-Uda antenna is then developed that radiates a directed endfire beam. A multiport circular array of these antennas is optimized to provide beam coverage over the full 360 degrees azimuthal plane. A sector of this circular array of monopole-based Yagi-Uda antennas was simulated, fabricated, and measured to verify the concepts. Good agreement between the simulated and measured results is confirmed.

关键词： Yagi-Uda antennas Slot antennas Directive antennas Dipole antennas Microstrip antenna arrays Azimuthal plane Antenna radiation patterns Beam scanning circular array finite ground plane monopole array resonant slots Yagi-Uda antennas

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circular array OF OUTWARD SLOPING MONOPOLES FOR VEHICULAR DIVERSITY ANTENNAS

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 1988年第10期36卷 1365-1374页

作者： VAUGHAN, RG ANDERSEN, JB LANGHORN, MH AALBORG UNIV INST ELECTR SYSTAALBORGDENMARK EUROPEAN SPACE RES & TECHNOL CTR NOORDWIJKNETHERLANDS

A circular array of outward-sloping monopoles is analyzed as a diversity antenna for vehicle rooftop mounting. The monopoles are assumed to approximate minimum scattering antennas, have sinusoidal current distributions, and reside on an infinite, perfectly conducting ground plane. The envelopes of the received signals are considered Rayleigh distributed. The advantage of the array configuration is that the feedpoint spacing can be made almost arbitrarily small, even for a large number of branches. A three-element array with element lengths of 0.6 wavelengths and feedpoint spacing 0.1 wavelengths operating at 463 MHz was field-tested and the results are in good agreement with the analysis.

关键词： MONOPOLES received signal diversity antenna Rayleigh circular array

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circular array STAP

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IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS 2000年第2期36卷 510-517页

作者： Zatman, M MIT Lincoln Lab Lexington MA 02420 USA

Traditionally, space-time adaptive processing (STAP) for airborne early warning (AEW) radar has been applied to uniform linear arrays (ULAs). However, when considering the overall radar system, electronically scanned circular arrays have advantages: a better combination of even and continual angular and temporal coverage, and mechanical simplicity because it does not need to rotate. This paper answers the question "How well does STAP perform when applied to a circular array?" This paper shows that for the AEW mission, circular arrays are indeed STAP compatible. However, when conventional STAP algorithms are used there may be a small loss in performance when compared with a ULA. With some care in the choice and implementation of the STAP algorithm, the majority of the degradation is at close ranges, where the target returns are relatively strong. At long ranges performance is barely affected. A STAP algorithm which compensates for the circular array environment and provides better performance than existing algorithms is presented.

关键词： Space time adaptive processing temporal coverage circular array short-distance Logic arrays Radar systems

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circular array AND ESTIMATION OF DIRECTION-OF-ARRIVAL OF A BROAD-BAND SOURCE

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SIGNAL PROCESSING 1994年第2期37卷 243-254页

作者： PADMINI, CU NAIDU, PS INDIAN INST SCI DEPT ECEBANGALORE 560012KARNATAKAINDIA

A circular array for estimation of direction of arrival (DOA) of a broadband source is shown to possess several nice properties as compared to those of a linear array. In addition to already known properties of a circular array, namely, lack of left-right ambiguity and resolution independent of bearing, we have shown that (i) in DOA estimation of a broadband source with circular array it is possible to avoid the frequency-direction ambiguity even without the use of delay elements except when two sources happen to be 180-degrees apart;(ii) inter sensor spacing need not be less-than-or-equal-to lambda(min)/2. On account of the last property it is possible to create a large aperture circular array without increasing the number of sensors, instead using a large number of tap delay elements. This would however result in increased processing complexity. Such a large aperture circular array is found to possess superior resolution capability and robustness.

关键词： circular array DOA estimation Subspace Broadband signal Large aperture Frequency-direction ambiguity

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A circular array FOR PLANE-WAVE SYNTHESIS

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IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY 1988年第1期30卷 3-8页

作者： HILL, DA UNIV COLORADO DEPT ELECT & COMP ENGNBOULDERCO 80309

A circular array of electric line sources for generating a uniform plane wave in the interior region of the array is analyzed. Identical results for the synthesized element weightings are obtained using matrix inversion or a Fourier series technique. A physical optics approximation for the element weightings is also presented, but it yields a much poorer result for the synthesized field. The angle of arrival of the plane wave can be scanned by recalculating the element weightings, and the quality of the field is maintained. Frequency scanning is also possible, but the number of array elements limits the maximum frequency.

关键词： uniform plane wave Plane waves Angle of arrival circular array maximum frequency array Element frequency scanning line source matrix inversion Fourier series

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A Realistic Multiple circular array System for Active Noise Control Over 3D Space

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IEEE-ACM TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING 2020年 28卷 3041-3052页

作者： Sun, Huiyuan Abhayapala, Thushara D. Samarasinghe, Prasanga N. Australian Natl Univ Res Sch Engn Canberra ACT 2601 Australia

Spatial active noise control (ANC) systems focus on minimizing unwanted acoustic noise over a continuous spatial region. Conventionally, spatial ANC systems are proposed using point based multi-channel systems and recently novel methods have been developed using spherical harmonic analysis of spatial sound fields. A major limitation for implementing the latter approach is the requirement of regularly distributed microphones and loudspeakers over spherical surfaces. In this paper, we relax the above constraint by constructing a system utilizing multiple circular microphone and loudspeaker arrays and designing a corresponding ANC algorithm. By simulation, we show that the proposed method can achieve comparable ANC performance to conventional spherical array methods. By experiment, we demonstrate the feasibility of implementing the multiple circular array structure and verify its effectiveness given practical constraints.

关键词： Harmonic analysis Loudspeakers Apertures Microphone arrays Three-dimensional displays Scattering Geometry array design circular array spatial ANC spherical harmonics

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STUDIES ON A 120-DEGREES SEGMENTED circular array FOR MULTIBEAM MULTIFREQUENCY BATHYMETRIC APPLICATION

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JOURNAL OF SOUND AND VIBRATION 1995年第1期179卷 1-12页

作者： CHAKRABORTY, B NATL INST OCEANOG PANAJI 403004 GOA INDIA

A theoretical analysis of the vertical far field patterns and input impedances, as well as excitation velocities of a 120 degrees segmented circular array of 40 groups of four elements each is performed. The narrowest beam widths at normal incidence and other steering angles support the use of such an array for bathymetric applications. The half-power beam widths at different steering angles are found to be comparable with the computed values of the half-power beam widths of a linear array of equivalent size. The present study of the mutual interaction effect between the array elements reveals that the interaction effects are relatively less for a 120 degrees segmented circular array. Furthermore, the 120 degrees segmented circular array geometry for multi-frequency use is found suitable after carrying out a study at different operating wavelengths that are useful for underwater bathymetric applications.

关键词： multiple-frequency Beam width Theoretical analysis impedance arrays interaction effect circular array Steering array Element linear arrays normal incidence

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