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This paper presents an ultrasound transceiver application-specific integrated circuit (ASIC) directly integrated with an array of 12 × 80 piezoelectric transducer elements to enable next-generation ultrasound probes for 3D carotid artery imaging. The ASIC, implemented in a 0.18 µm high-voltage Bipolar-CMOS-DMOS (HV BCD) process, adopted a programmable switch matrix that allowed selected transducer elements in each row to be connected to a transmit and receive channel of an imaging system. This made the probe operate like an electronically translatable linear array, allowing large-aperture matrix arrays to be interfaced with a manageable number of system channels. This paper presents a second-generation ASIC that employed an improved switch design to minimize clock feedthrough and charge-injection effects of high-voltage metal-oxide-semiconductor field-effect transistors (HV MOSFETs), which in the first-generation ASIC caused parasitic transmissions and associated imaging artifacts. The proposed switch controller, implemented with cascaded non-overlapping clock generators, generated control signals with improved timing to mitigate the effects of these non-idealities. Both simulation results and electrical measurements showed a 20 dB reduction of the switching artifacts. In addition, an acoustic pulse-echo measurement successfully demonstrated a 20 dB reduction of imaging artifacts.
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http://dx.doi.org/10.3390/s21010150 | DOI Listing |
Sensors (Basel)
August 2025
Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA.
One of the keys to medical microwave tomography is understanding the sensitivity of transmit-receive signals to changes in the electromagnetic properties to be reconstructed. This information is embedded in the Jacobian matrix for traditional inverse problem approaches and is a function of transmitter-receiver design characteristics and associated signal radiation/detection patterns. Previous efforts focused primarily on the 2D imaging problem for which sensitivity maps were generated in a single plane.
View Article and Find Full Text PDFNMR Biomed
July 2025
Department of Radiology, University of Missouri Columbia, Columbia, Missouri, USA.
The hippocampus is known to be a key site of pathology for dementia and epilepsy, consistent with its role in memory formation. With this brain region also known to be vulnerable to metabolic injury, spectroscopic studies of the hippocampus are of relevance. However, the hippocampus is a challenging region for measurement, given its irregular small size and the high susceptibility gradients (e.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
June 2025
Ultrasonography could allow operator-independent examination and continuous monitoring of the carotid artery (CA) but normally requires complex and expensive transducers, especially for 3-D. By employing computational ultrasound imaging (cUSi), using an aberration mask and model-based reconstruction, a monitoring device could be constructed with a more affordable simple transducer design comprising only a few elements. We aim to apply the cUSi concept to create a CA monitoring system.
View Article and Find Full Text PDFMagn Reson Med
July 2025
Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
Purpose: To evaluate the feasibility of interleaved Na/H cardiac MRI at 7 T using H parallel transmission (pTx) pulses.
Methods: A combined setup consisting of a Na volume coil and two H transceiver arrays was employed and the transmit and receive characteristics were compared in vitro with those of the uncombined radiofrequency coils. Furthermore, the implemented interleaved Na/H pTx sequence was validated in phantom measurements and applied to four healthy subjects.
Magn Reson Med
June 2025
Center for Magnetic Resonance Research, Radiology Department, University of Minnesota, Minneapolis, Minnesota, USA.
Purpose: Phosphorus-31 (P) MR spectroscopy imaging (MRSI) at 7 T is a powerful tool for investigating high-energy phosphate metabolism in human brains with significantly improved signal-to-noise ratio (SNR) and spectral resolution. However, this imaging technique requires dual-frequency radiofrequency coil for performing brain anatomical imaging and B shimming at proton (H) operation frequency, and P MRSI at lower operation frequency. Herein, we introduce a novel P-H dual-frequency radiofrequency coil design using a double-tuned and double-matched (DODO) coil that does not require complex circuitry or two coil layers and exhibits similar imaging performance as to single-frequency control coils for both P and H imaging operations.
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