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Fast Orthogonal Row-Column Electronic Scanning Experiments and Comparisons

IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS ANd FREQUENCY CONTROL 2019年第6期66卷 1093-1101页

作者： Ceroici, Chris Latham, Katherine Greenlay, Benjamin A. Brown, Jeremy A. Zemp, Roger J. Univ Alberta Dept Elect & Comp Engn Edmonton AB T6G 2R3 Canada Dalhousie Univ Dept Elect & Comp Engn Halifax NS B3H 4R2 Canada

Three-dimensional ultrasound imaging presents the technical challenges of addressing large numbers of elements in 2-d array transducers. Top-orthogonal-to-bottom electrode (TOBE) 2-d transducer arrays can simplify addressing but typical imaging methods with such arrays enable only one-way focusing in azimuth and elevation. Here, experimental results are reported for the fast orthogonal row-column electronic scanning (FORCES) imaging scheme implemented on a 64 x 64 element bias-sensitive electrostrictive relaxor TOBE array. The FORCES imaging scheme involves transmitting along rows to form an elevational transmit focus, while biasing columns with bias patterns selected from a Hadamard matrix. Channel data from columns is received and decoded for synthetic-aperture beamforming in azimuth. This scheme offers two-way azimuthal focusing. The volumetric imaging experiments were conducted using wire phantoms as well as on rat hearts using two different TOBE imaging schemes: Scheme 1 (transmit focusing in elevation and receive focusing in azimuth) and FORCES. Wire phantom experiments at a depth of 2 cm showed an azimuthal resolution of 0.42 and 0.31 mm with Scheme 1 and FORCES, respectively. We also compared the elevational imaging performance of these imaging schemes with a mechanically scanned linear array. The FORCES imaging displayed an elevational resolution of 0.46 mm at a depth of 2 cm, and the linear array displayed an elevational resolution of 0.72 cm. The novel TOBE array architecture and FORCES imaging scheme thus enable high-quality 3-d ultrasound imaging using only row-column addressing and bias control and may prove an enabling technology for many future 3-d imaging platforms.

关键词： 2-d array 3-d imaging crossed-electrode array

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Ex Vivo HIFU Experiments Using a 32 x 32-Element CMUT array

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IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS ANd FREQUENCY CONTROL 2016年第12期63卷 2150-2158页

作者： Yoon, Hyo-Seon Chang, Chienliu Jang, Ji Hoon Bhuyan, Anshuman Choe, Jung Woo Nikoozadeh, Amin Watkins, Ronald d. Stephens, douglas N. Pauly, Kim Butts Khuri-Yakub, Butrus T. Stanford Univ Edward L Ginzton Lab Stanford CA 94305 USA Apple Inc Cupertino CA 95014 USA Stanford Univ Dept Radiol Stanford CA 94305 USA Univ Calif Davis Dept Biomed Engn Davis CA 95616 USA

High-intensity focused ultrasound (HIFU) has been used as noninvasive treatment for various diseases. For these therapeutic applications, capacitive micromachined ultrasonic transducers (CMUTs) have advantages that make them potentially preferred transducers over traditional piezoelectric transducers. In this paper, we present the design and the fabrication process of an 8 x 8-mm(2) 32 x 32-element 2-d CMUT array for HIFU applications. To reduce the system complexity for addressing the 1024 transducer elements, we propose to group the CMUT array elements into eight HIFU channels based on the phase delay from the CMUT element to the targeted focal point. designed to focus at an 8-mm depth with a 5-MHz exciting frequency, this grouping scheme was realized using a custom application-specific integrated circuit. With a 40-V dc bias and a 60-V peak-to-peak ac excitation, the surface pressure was measured 1.2 MPa peak-to-peak and stayed stable for a long enough time to create a lesion. With this dc and ac voltage combination, the measured peak-to-peak output pressure at the focus was 8.5 MPa, which is expected to generate a lesion in a minute according to the temperature simulation. The following ex vivo tissue experiments successfully demonstrated its capability to make lesions in both bovine muscle and liver tissue.

关键词： 2-d array capacitive micromachined ultrasonic transducers (CMUTs) dual-mode ultrasound high-intensity focused ultrasound (HIFU) therapeutic ultrasound thermal ablation

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Real-time 3d transesophageal echocardiography

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ULTRASONIC IMAGING 2004年第4期26卷 217-232页

作者： Pua, EC Idriss, SF Wolf, Pd Smith, SW Duke Univ Dept Biomed Engn Durham NC 27708 USA Duke Univ Med Ctr Dept Pediat Durham NC 27708 USA

Transesophageal echocardiography (TEE) is an essential diagnostic tool in patients with poor transthoracic echocardiographic windows or when detailed imaging of structures distant from the chest wall is necessary. A real-time 3 d TEE probe has been fabricated in our laboratory in order to increase the amount of information available during a transesophageal procedure. The I cm diameter esophageal probe utilizes a 2-dimensional, 5 MHz array at its tip with a 6.3 mm diameter aperture, including 50 Omega active channels. The array has a periodic vernier geometry with an element pitch of 0.18 mm, built onto a multi layer flexible (MLF) interconnect circuit. In order to accommodate 504 channels within the device, a 1 to long Gore MicroFlat (TM) cable was utilized for wiring the MLF to the corresponding system connectors. Pulse-echo tests in a water tank have yielded a -6 dB bandwidth of 25.3%. Fully connected to the system through 3 m of cable, the probe shows an average 50 Omega insertion loss of -85 dB with a standard deviation of 4 dB, as determined through pitch-catch measurements for a sampling of 10 elements. Using the completed 3 d TEE probe with the Volumetrics Medical Imaging 3d scanner, real-time volumetric images of in vivo canine cardiac anatomy have been acquired, displaying atrial views, mitral valve function and interventional catheter guidance.

关键词： 2-d array real-time transesophageal echocardiography volumetric

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Two-dimensional Planar array for digital Beamforming and direction-of-Arrival Estimations

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2009年第7期58卷 3137-3144页

作者： Kim, Shinho Wang, Yuanxun Ethan Univ Calif Los Angeles Dept Elect Engn Los Angeles CA 90034 USA

A compact uniplanar design of 2-d antenna arrays is presented for digital beamforming (dBF) and direction-of-arrival (dOA) estimations. The array is based on switchable microstrip slot antennas that are series fed in one dimension and parallel fed in the other dimension. In conjunction with spatial multiplexing of local elements (SMILE) techniques, the array is able to use both the series- and parallel-fed antennas for 2-d beamforming and dOA estimations. The combination of series and parallel feeding provides a simple way of constructing 2-d dBF arrays with a simple and uniplanar feed network. Other advantages are its low cost and compatibility with a microwave integrated circuit process for the receiver system. A 4 x 4 receiving array test bed at a 5.5-GHz operating frequency is fabricated, and dBF and dOA tests on this test bed are successfully demonstrated.

关键词： digital beamforming (dBF) direction-of-arrival (dOA) estimations planar array slot antennas spatial multiplexing of local elements (SMILE) 2-d array

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T/R Switch Composed of Three HV-MOSFETs With 12.1-μW Consumption That Enables Per-Channel Self-Loopback AC Tests and-18.1-dB Switching Noise Suppression for 3-d Ultrasound Imaging With 3072-Ch Transceiver

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IEEE TRANSACTIONS ON VERY LARGE SCALE INTEGRATION (VLSI) SYSTEMS 2022年第2期30卷 153-165页

作者： Kajiyama, Shinya Igarashi, Yutaka Yazaki, Toru Katsube, Yusaku Nishimoto, Takuma Nakagawa, Tatsuo Nakamura, Yohei Hayashi, Yoshihiro Kaneko, Takuya Ishikuro, Hiroki Yamawaki, Taizo Hitachi Ltd Ctr Technol Innovat Instrumentat Res & Dev Grp Tokyo 1858601 Japan Hitachi Ltd Ctr Technol Innovat Prod Engn Tokyo 1858601 Japan Hitachi Ltd MONOZUKURI Res & Dev Grp Tokyo 1858601 Japan Hitachi Ltd Ctr Technol Innovat Healthcare Res & Dev Grp Tokyo 1858601 Japan FUJIFILM Healthcare Corp US Diagnost Res & Dev Div Tokyo 1850014 Japan FUJIFILM Healthcare Corp Ultrasound Diagnost Syst Div Tokyo 1850014 Japan Keio Univ Dept Elect & Elect Engn Yokohama Kanagawa 2238522 Japan

This article presents an area- and power-efficient transmission/receiving (TX/RX)-isolation switch implemented in a 3072-ch ultrasound (US) in-probe 2-d array transceiver application-specific integrated circuit (ASIC) for real-time 3-d imaging. Conventional T/R switches that protect low voltage (LV) receivers from high voltage (HV) bipolar pulses require at least four HV-MOSFETs. The proposed dynamic gate-source shunt topology, which utilizes a negative-HV-transmit-driven shunt switch, eliminates area- and power-hungry HV-level shifters and ensures the OFF state of our T/R switch for HV/LV isolation during TX periods. In addition, source-driven HV-PMOS for ON/ control enables both gate charging and discharging using a single HV-PMOS. Thus, our T/R switch enables implementation with only three HV-MOSFETs for the first time in the world. The HV-level-shifter-less architecture also enables static-power-free operation in TX periods and consumption of only 12.1 mu W in RX periods. Further, sequential input impedance control suppresses switching noise, which causes unwanted sound transmitted during TX to RX switching, by -18.1 dB. Moreover, by preparing an attenuation mode, a per-channel TX to RX self-loopback test can be performed. This function provides an on-wafer ac test without probing 3072 electrodes and it can be applied to the field diagnosis of assembled US probes.

关键词： Switches Probes Ultrasonic imaging Costs Transmission line matrix methods Transceivers Medical services 2-d array 3-d imaging high voltage (HV)-switch loopback test matrix transducer switching noise T R switch ultrasound (US)

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High-power vertical-cavity surface-emitting lasers for diode pumped solid-state lasers

High-power vertical-cavity surface-emitting lasers for diode...

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Conference on Laser Technology for defense and Security VIII

作者： Van Leeuwen, Robert Xiong, Yihan Seurin, Jean-Francois Xu, Guoyang Miglo, Alexander Wang, Qing Xu, Bing Zou, Wei-Xiong Li, daizong Wynn, James d. Khalfin, Viktor Ghosh, Chuni L. Princeton Optron Inc Princeton NJ 08619 USA

ISBN: (纸本)9780819490599

Vertical-cavity surface-emitting lasers can be processed in large two-dimensional arrays of single devices to scale up the power for solid-state laser pumping. These arrays emit in a circular, uniform beam, with a narrow and stable emission spectrum that is well suited to the absorption spectra of solid-state gain media. kW-class 808 nm QCW VCSEL pump modules were developed to pump compact Nd:YAG lasers. An end-pumped Nd: YAG laser was constructed that produced 7.1 W average IR power, as well as a dual side-pumped passively Q-switched frequency-quadrupled Nd: YAG laser that generated 0.8 mJ UV pulses at a 240 Hz repetition rate.

关键词： Semiconductor laser diode-pumped solid-state laser vertical-cavity surface-emitting laser high power laser 2-d array 808 nm UV laser

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An Innovative and Simple Impedance Matching Network Using Stacks of Metasurface Sheets to Suppress the Mismatch Between Antennas and RF Front-End Transceivers Circuits 15

An Innovative and Simple Impedance Matching Network Using St...

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15th European Conference on Antennas and Propagation (EuCAP)

作者： Alibakhshikenari, Mohammad Virdee, Bal S. Althuwayb, Ayman A. Falcone, Francisco Limiti, Ernesto Univ Roma Tor Vergata Elect Engn Dept Via Politecn 1 I-00133 Rome RM Italy London Metropolitan Univ Ctr Commun Technol London N7 8DB England Jouf Univ Elect Engn Dept Sakaka 72388 Aljouf Saudi Arabia Univ Publ Navarra Elect Elect & Commun Engn Dept Pamplona Spain Univ Publ Navarra Inst Smart Cities Pamplona 31006 Spain

ISBN: (纸本)9788831299022

A innovative and simple impedance matching network is presented that is implemented by stacking together metasurface (MTS) sheets. The technique is shown to reduce the mismatch between free-space and RF front-end antenna of a receiver. The MTS based impedance matching network is modeled as a transmission-line loaded with shunt and series capacitances and inductances, respectively. The proposed MTS impedance matching network can be employed to effectively interface the frees-pace to the antenna of an RF receiver and thereby optimize power absorption. Each MTS impedance matching sheet comprises two-dimensional periodic array of subwavelength microstrip resonator unit-cells that are spaced at a wavelength that is smaller than the frequency of operation. The unit-cells are square shaped patches and embedded with cross-shaped slots that are grounded through a via-hole. The MTS impedance matching network was fabricated using FR-4 substrate. 3d full-wave EM tool by Ansys HFSS (TM) was used to verify its effectiveness. The proposed MTS impedance matching sheet is relatively easy to implement in practice.

关键词： Antenna impedance matching network metasurface (MTS) RF front-end transceivers 2-d array microstrip resonators

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Circularly Polarized Antenna array Based on Open End Waveguide

Circularly Polarized Antenna Array Based on Open End Wavegui...

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International Symposium of Applied-Computational-Electromagnetics-Society (ACES)

作者： Jovicic, Milos M. Kolundzija, Branko M. Univ Belgrade Sch Elect Engn Belgrade Serbia Univ Belgrade Sch Elect Engn Dept Gen Elect Engn Belgrade Serbia

ISBN: (纸本)9781733509602

Proposed type of the waveguide 2-d array combines simplicity of the design and manufacturing of the waveguide components with its good performances. Comparing it to the commonly used waveguide slot antennas, they offer stable main beam direction at wide frequency range. In addition, simple method of forming a linear array is easily applicable here, which leads to high gain antenna system. The whole process of modeling and simulations is performed using WIPL-d Pro CAd EM simulation software.

关键词： 2-d array high gain waveguide WIPL-d software

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design method for large 2-d ultrasonic arrays with controlled grating lobes levels

Design method for large 2-D ultrasonic arrays with controlle...

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IEEE Ultrasonics Symposium

作者： Villazon, J. Ibanez, A. Parrilla, M. Nevado, P. CSIC IAI Arganda Del Rey Spain

ISBN: (纸本)9781424424283

A major problem in developing 2-d arrays is the large number of elements required for big apertures in order to produce high quality ultrasonic images. Recent advances in transducer technology have made possible to design arrays with fewer restrictions in the shape and layout or elements. In this paper we propose to use Evolutionary Algorithms to optimize these parameters to obtain large 2-d ultrasonic arrays with a low number of elements but maintaining a narrow mainlobe and low grating lobes level.

关键词： component: Optimization 2-d array Evolutionary algorithms

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Real-time transrectal 3-d ultrasound using synthetic aperture

Real-time transrectal 3-D ultrasound using synthetic apertur...

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Medical Imaging 2006 Conference

作者： Yen, Jesse T. Seo, Chi Hyung daher, Nadim M. Univ Southern Calif Dept Biomed Engn Los Angeles CA 90089 USA

ISBN: (纸本)0819461903

In previous work, we investigated 3-d synthetic aperture imaging with 2-d array designs for real-time rectilinear volumetric imaging of targets near the transducer such as the breast and carotid artery. Here we present results for cylindrical 3-d imaging for 3-d transrectal ultrasound (TRUS). The major benefit of this design is the interconnect where an expensive multilayer flex circuit is no longer required. The interconnect uses a row-column addressing scheme to enable different groups of elements. Over 256 transmissions, this design is capable of synthesizing a 256 x 256 = 65,536 element fully sampled 2-d cylindrical array if desired. In receive, the echoes from individual elements along a row are recorded by the system receive channels. For faster volume acquisition time, we present a design where all elements of the 2-d array transmit simultaneously, and signals are recorded one row at a time. For a depth of 6 cm, a volume rate of 50 volumes/s can be achieved. We have performed computer simulations of a 10 MHz 256 x 256 synthetic cylindrical 2-d array with a radius of curvature of 10 min to determine the radiation pattern. For an 128 x 128 subaperture, the on-axis case (x,y,z) = (0,0,20) mm showed a narrow beam down to -40 dB. In the transversal direction, on-axis lateral beamwidths at -6, -20, and -40 dB were 0.47 mm, 0.81 mm, and 2.54 mm, respectively. As for the longitudinal direction, the beamwidths are slightly narrower than in transversal direction, giving 0.39 mm, 0.72 mm, and 1.51 min for the same corresponding dB levels.

关键词： 3-d ultrasound prostate 2-d array real-time synthetic aperture

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