Purpose: To demonstrate the feasibility of using a double loop phased array endorectal coil combined with a phased array body coil to image the prostate at 3T.
Materials And Methods: We designed and constructed a novel prostate coil employing two arrayed 4.0 x 5.0 cm loops, tuned the device for optimal performance at 3T, and characterized the signal-to-noise ratio (SNR) associated with it.
Results: The coil Q factor was calculated to be approximately 50 unloaded, and 30 when loaded on human tissue. SNR maps at multiple orientations were constructed and images were acquired on both a phantom and a human. As expected, SNR was highest along the midpoint of the array and demonstrated strong signal even at 4 cm from the coil.
Conclusion: The double loop phased array endorectal coil combined with a phased array body coil at 3T is feasible in vivo and compelling enough to warrant future clinical trials to evaluate its efficacy. These trials are currently under way.
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http://dx.doi.org/10.1002/jmri.21389 | DOI Listing |
A silicon photonics optical phased array with a two-dimensional matrix of antennas is experimentally demonstrated in which the unitary antennas are optimized such that light can be emitted over a high fraction of the overall array surface. This design strategy can be used to obtain a low divergence emitted beam containing a significant fraction of the total emitted power, at the expense of a reduced beam steering range. This type of device can be suited to phase front correction in optical wireless communications systems.
View Article and Find Full Text PDFTerahertz reconfigurable intelligent surfaces (RIS) stand out from conventional phased arrays thanks to their unique electromagnetic properties and intelligent interconnect paradigms. They are a vital technology for terahertz wireless communication and radar detection systems. Compared with 1-bit coding metasurfaces, 2-bit coding metasurfaces offer significant advantages such as single beam steering and reduced quantization errors.
View Article and Find Full Text PDFFor the application scenario of multi-user, high-bandwidth laser communication in satellite internet, this paper proposes a spatiotemporal vector optimization algorithm to achieve high energy utilization in arbitrary multi-beam generation using a liquid crystal optical phased array antenna. The core components of this method involve optimizing phase offsets and power coefficients through iterative processes to achieve precise beam shaping and efficient energy distribution among multiple beams. This approach overcomes the single-link limitation of traditional laser terminals and resolves challenges such as low radiation efficiency and substantial power loss in multi-beam generation systems utilizing passive phased array antennas.
View Article and Find Full Text PDFNat Commun
January 2025
State Key Laboratory for Extreme Photonics and Instrumentation, International Research Center for Advanced Photonics, Ningbo Innovation Center, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310058, China.
The frequency-modulated continuous-wave (FMCW) technology combined with optical phased array (OPA) is promising for the all-solid-state light detection and ranging (LiDAR). We propose and experimentally demonstrate a silicon integrated OPA combined with an optical frequency microcomb for parallel LiDAR system. For realizing the parallel wavelengths emission consistent with Rayleigh criterion, the wide waveguide beyond single mode region combined with the bound state in the continuum (BIC) effect is harnessed to obtain an ultra-long optical grating antenna array.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
School of Control Science and Engineering, Shandong University, Ji'nan 250061, China.
Carbon fiber reinforced plastics inevitably develop defects such as delamination, inclusions, and impacts during manufacturing and usage, which can adversely affect their performance. Ultrasonic phased array inspection is the most effective method for conducting nondestructive testing to ensure their quality. However, the diversity of defects within carbon fiber reinforced plastics makes it challenging for the current ultrasonic phased array inspection techniques to accurately identify these defects.
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