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A 32-Channel Sleeve Antenna receiver array for Human Head MRI Applications at 10.5 T

IEEE TRANSACTIONS ON MEDICAL IMAGING 2023年第9期42卷 2643-2652页

作者： Woo, Myung Kyun Delabarre, Lance Waks, Matt Lagore, Russell Kim, Jeehoon Jungst, Steve Eryaman, Yigitcan Ugurbil, Kamil Adriany, Gregor Hankuk Univ Foreign Studies Div Biomed Engn Yongin 17035 South Korea Univ Ulsan Sch Elect Engn Dept Biomed Engn Ulsan 44610 South Korea Univ Minnesota Ctr Magnet Resonance Res CMRR Minneapolis MN 55455 USA Case Western Reserve Univ Dept Elect Engn Cleveland OH 44106 USA Cleveland Clin Program Adv Musculoskeletal Imaging PAMI Cleveland OH 44196 USA

For human brain magnetic resonance imaging (MRI), high channel count (=32) radiofrequency receiver coil arrays are utilized to achieve maximum signal-to-noise ratio (SNR) and to accelerate parallel imaging techniques. With ultra-high field (UHF) MRI at 7 tesla (T) and higher, dipole antenna arrays have been shown to generate high SNR in the deep regions of the brain, however the array elements exhibit increased electromagnetic coupling with one another, making array construction more difficult with the increasing number of elements. Compared to a classical dipole antenna array, a sleeve antenna array incorporates the coaxial ground into the feed-point, resulting in a modified asymmetric antenna structure with improved intra-element decoupling. Here, we extended our previous 16-channel sleeve transceiver work and developed a 32-channel azimuthally arranged sleeve antenna receive-only array for 10.5 T human brain imaging. We experimentally compared the achievable SNR of the sleeve antenna array at 10.5 T to a more traditional 32-channel loop array bult onto a human head-shaped former. The results obtained with a head shaped phantom clearly demonstrated that peripheral intrinsic SNR can be significantly improved compared to a loop array with the same number of elements - except for the superior part of the phantom where sleeve antenna elements are not located.

关键词： Antenna arrays Receiving antennas Dipole antennas Magnetic resonance imaging Coaxial cables Signal to noise ratio UHF antennas Dipole antenna magnetic resonance imaging radiofrequency coil receiver array sleeve antenna ultra-high field

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Spatially Distributed Polarization receiver array for Communication and Sensing Multifunction Systems 54

Spatially Distributed Polarization Receiver Array for Commun...

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54th European Microwave Conference (EuMC)

作者： Deng, Jie Burasa, Pascal Keivaan, Seyed Ali Wu, Ke Polytech Montreal Poly Grames Res Ctr Montreal PQ Canada

ISBN: (纸本)9798350385892;9782874870774

In this work, a spatially distributed one-dimensional (1-D) receiver array for future polarized multifunction communication and sensing systems is introduced and presented for the first time. Different from the conventional receiver array, the proposed receiver system based on the orthomode transducer (OMT) enables the dual-polarization property without adding the number of receiver blocks. Besides, due to the 1-D spatial distribution, not only does this OMT array significantly improve the communication capacity, but also it can achieve multifunction sensing applications such as typical angle-of-arrival (AoA) and polarization detection. To validate the proposed concept, a theoretical analysis of the proposed receiver array is derived and presented. Then, an experimental 6-cell proof-of-concept prototype is developed, fabricated, and measured. The demodulated 4-QAM and 16-QAM signals confirm the good performance of the proposed OMT receiver array.

关键词： Dual-polarization interferometric techniques multifunction millimeter-wave receiver array sensing system terahertz (THz) wireless communication system

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A numerical model for optimal receiver array and mass flow rate in residential solar water heating systems

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INTERNATIONAL JOURNAL OF SUSTAINABLE ENERGY 2018年第9期37卷 902-918页

作者： Coetzee, Rigardt Alfred Maarten Mwesigye, Aggrey Huan, Zhongjie Tshwane Univ Technol Dept Mech Engn Mechatron & Ind Design Pretoria South Africa Univ Witwatersrand Sch Mech Ind & Aeronaut Engn Johannesburg South Africa

In this paper, the performance of a pressurised evacuated tube solar collector system using internal heat pipes is presented. The system was optimised for the seasonal supply of hot service water for residential use in Pretoria, South Africa. The prediction of seasonal hourly performance trends along with the maximum thermal performance at the optimal receiver array and manifold mass flow rate was of major concern in this investigation. A mathematical model representing the thermal performance of the system was developed and numerically implemented in Engineering Equation Solver. The dynamic performance of collectors with 15, 20 and 25 tubes was determined throughout all the seasons. Moreover, the performance of the residential solar water heating system with a 20-tube collector was investigated in detail for mass flow rates of 0.03, 0.05 and 0.07 kg/s.

关键词： Solar thermal evacuated tube collectors solar water heating heat pipe manifold mass flow rate receiver array

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Acoustic Wireless Power Transfer with receiver array for Enhanced Performance

Acoustic Wireless Power Transfer with Receiver Array for Enh...

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IEEE Wireless Power Transfer Conference (WPTC)

作者： Tseng, Victor Farm-Guoo Bedair, Sarah S. Lazarus, Nathan US Army Res Lab Oak Ridge Associated Univ Fellowship Program Adelphi MD 20783 USA US Army Res Lab Sensors & Elect Devices Directorate Adelphi MD USA

ISBN: (纸本)9781509045853

Achieving wireless power transfer through airborne acoustic/ultrasonic waves has been previously shown to be a feasible alternative when the charging distance is above several times the transducer size. In order to further increase the receiver efficiency, constructing the receiver out of an array of transducer elements to increase the receiver effective area is desirable. In this work, a study on the power combining through series or parallel interconnections of the receiver elements is done to understand the benefits of both cases and the conditions required to maximize receiver efficiency, with measurements and modeling results presented. With a seven element receiver array, a factor of 4.25 increase in receiver efficiency was achieved compared to only using the receiver center transducer.

关键词： Ultrasonic transducers wireless power transfer receiver array power combining acoustic focusing beam steering

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Dedicated receiver array coil for ¹H lung imaging with same-breath acquisition of hyperpolarized ³He and ¹²⁹Xe gas

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MAGNETIC RESONANCE IN MEDICINE 2015年第1期74卷 291-299页

作者： Rao, Madhwesha Robb, Fraser Wild, Jim M. Univ Sheffield Unit Acad Radiol Sheffield S Yorkshire England GE Healthcare Cleveland OH USA

PurposeSame-breath acquisition of H-1 and hyperpolarized gases (He-3 and Xe-129) in the lungs provides complementary information on pulmonary structure and function with inherent spatial-temporal registration of the images from the different nuclei. To date H-1 images have been acquired using the MR system's body coil, which has low SNR when compared with dedicated receiver-array coils. This study demonstrates the design and application of a dedicated H-1 receiver array to improve the H-1 lung SNR for use in same-breath acquisition with hyperpolarized gas He-3 or Xe-129 at 1.5 Tesla. Theory and MethodsA four-loop dedicated receiver-array was developed in-house for H-1 lung MRI to work in compatibility with existing He-3/Xe-129 transmit-receive coils. As part of the design process, a new generalized circuit formalism was developed for trap circuits for such a dedicated H-1 receiver array at 63.8 MHz with traps for He-3 48.6 MHz and Xe-129 17.7 MHz. ResultsThe H-1 lung image SNR from the novel H-1 array was twice that observed with the H-1 body coil when used in same-breath acquisition with the He-3 or Xe-129 T-R coil in situ. ConclusionAn array coil to improve H-1 SNR of the lung in same-breath acquisition with hyperpolarized gases has been demonstrated. Magn Reson Med 74:291-299, 2015. (c) 2014 Wiley Periodicals, Inc.

关键词： receiver array pulmonary lungs hyperpolarized gas

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Providing a simple and efficient algorithm for passive sound localization

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OCEAN ENGINEERING 2022年 261卷

作者： Nouri, Nowrouz Mohammad Zare, Mehdi Iran Univ Sci & Technol Sch Mech Engn Tehran Iran

The sound source localization (SSL) system is one of the main approaches for detecting targets. This kind of localization method is carried out in a passive way, without the emission of any signals, and cannot be detected easily. This paper investigates the two-dimensional SSL of stationary targets using only three receivers. Given that, flow-induced noise of the bluff-bodies in viscous fluids is one of the most important noise generation sources, firstly, this noise is simulated numerically. Due to the distance between the receivers in an array, the sound reaches the receiver with time delay. High accuracy SSL needs highly accurate time delays measurement. In the following, time delays are obtained by calculating the cross-correlation in a time domain of sound signals arriving at the receiver array, and next, the bearing angle of the sound source is estimated. Later, using a new, simple (easy installation), fast (real-time), and accurate pure geometric algorithm, the source candidate locations are obtained. Then, using an elimination algorithm, the ambiguity of the noise source location is removed, and source imaginary locations are removed. Finally, this process is validated by a physical algorithm. Numerical results verify the effectiveness of this geometric algorithm.

关键词： Sound source localization Time difference of arrival Cross-correlation Bearing angle receiver array Flow noise

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A 16-Element W-Band Phased-array Transceiver Chipset With Flip-Chip PCB Integrated Antennas for Multi-Gigabit Wireless Data Links

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IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES 2018年第7期66卷 3389-3402页

作者： Shahramian, S. Holyoak, M. J. Baeyens, Yves Bell Labs Murray Hill NJ 07974 USA

This paper describes the design and implementation of a W-band phased-array system with printed circuit board (PCB) integrated antennas in two polarizations capable of multi-gigabit spectrally efficient wireless communication. The chipset is manufactured in a 0.18-mu m SiGe BiCMOS technology with f(T)/f(MAX) of 240-/270-GHz and is flip-chipped onto a low-cost organic PCB with integrated antenna arrays. Each chip is equipped with 16-transmit/4-receive or 16-receive/4-transmit calibrated phase shifter elements and direct up-and downconverters plus a half-rate phase-locked loop. The different system tradeoffs required to establish a multi-Gb/s wireless link at millimeter waves are carefully studied. Built-in element failure detectors, power detectors, and digital interface enable factory calibration and self-test capability. Each transceiver chip operates from 1.5- and 2.5-V supplies and consumes 5.5 and 4.5 W in transmit and receive mode, respectively. The peak transmitter effective isotropic radiation power is 34 dBm in each polarization with a measured receiver noise figure of 6.5 dB at 94 GHz. At a distance of 1 m, a maximum wireless data rate of 30 Gb/s (per polarization) using 64-QAM can be achieved and at 20 m, 8 Gb/s (dual polarization) can be established using QPSK modulation.

关键词： 5G wireless die on printed circuit board (PCB) direct conversion downconverter E-band integrated antenna millimeter wave monolithic microwave integrated circuit multi-gigabit wireless link phase-locked loop (PLL) phased-array calibration QAM constellation receiver array SiGe BiCMOS transmitter array upconverter W-band wireless link analysis

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Research on Strong Background Light Suppression Technology Based on Power Inversion 18

Research on Strong Background Light Suppression Technology B...

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18th International Conference on Optical Communications and Networks (ICOCN)

作者： Qin, Ling Song, Ke-ning Hu, Yong-zhen Li, Bao-shan Du, Yong-xing Inner Mongolia Univ Sci & Technol Sch Informat Engn Baotou 014010 Inner Mongolia Peoples R China

ISBN: (纸本)9781728127644

Because the direct background light generated by the sun is strong, its strong background light power is much higher than the LED's power, and the signal is completely submerged in the background noise, causing communication interruption. To solve the above problems, this paper establishes a visible light communication system between LED traffic lights and vehicles under strong background light, and introduces the power inversion algorithm into the system to suppress the influence of strong background light, then analyzes and compares the bit error rate of the systems under different signal-to-interference ratio. The simulation results show that the power inversion using the 3-element receiving array can generate a null of about -70dB in the direction of strong background light, so that the noise value of the output is significantly reduced, the signal gain remains unchanged. When the signal interference ratio of system is -15, the BER is 10(-4), which can supply the need of communication.

关键词： Visible light communication Strong background light Power inversion receiver array

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Long-range measurement system using ultrasonic range sensor with high-power transmitter array in air

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ULTRASONICS 2017年 74卷 186-195页

作者： Kumar, Sandev Furuhashi, Hideo Aichi Inst Technol Dept Elect & Elect Engn 1247 YachigusaYakusa Cho Toyota 4700392 Japan

A long-range measurement system comprising an ultrasonic range sensor with a high-power ultrasonic transmitter array in air was investigated. The system is simple in construction and can be used under adverse conditions such as fog, rain, darkness, and smoke. However, due to ultrasonic waves are well absorbed by air molecules, the measurable range is limited to a few meters. Therefore, we developed a high-power ultrasonic transmitter array consisting of 144 transmitting elements. All elements are arranged in the form of a 12 x 12 array pattern. The sound pressure level at 5 m from the transmitter array was >30 dB higher than that of a single element. A measuring range of over 25 m was achieved using this transmitter array in conjunction with a receiver array having 32 receiving elements. The characteristics of the transmitter array and range sensor system are discussed by comparing simulation and experimental results. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Ultrasonic sensor Range image Transmitter array receiver array Pulse modulation

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A Self-Alignment System for LOS Optical Wireless Communication Links

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IEEE PHOTONICS TECHNOLOGY LETTERS 2017年第24期29卷 2207-2210页

作者： Fahs, Bassem Romanowicz, Matthew Kim, Jacob Hella, Mona M. Rensselaer Polytech Inst Dept Elect Comp & Syst Engn Ctr Lighting Enabled Syst & Applicat Troy NY 12180 USA Lehigh Univ Elect & Comp Engn Dept Bethlehem PA 18015 USA

This letter presents a self-alignment system using a continuous and a proportional-to-position-error correction algorithm. The system is designed to address uninterrupted point-to-point high-speed line-of-sight optical wireless links. The alignment correction employs amplitude detection from a mm(2)-scale CMOS-compatible 4-PD array connected to a 4-channel receiver and followed by digital-processing and feedback toward the receiver lens position. The proposed self-alignment method is validated with a receiver position varying over about 5-cm range and a receiver angle covering around +/- 10 degree with roughly x4 field-of-view widening due to the automatic alignment. A 50-Mb/s ON-OFF-keying transmission link is maintained across 4 meters distance using a 650-nm-red light-emitting-diode source with a bit-error-rate below the forward-error-correction limit of 3.8 x 10(-3).

关键词： Alignment optical receiver receiver array optical wireless visible light communication VLC light-emitting-diode LED

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