Related papers: Coaxial Dipole Array with Switching Transmit Sensi…
Ultra-high field MRI (7T+) unlocks a new era of brain research with superior resolution and signal-to-noise. Capturing intricate neural activity and detailed soft tissue pathology, this technology, coupled with advanced RF coil arrays,…
Inhomogeneity of the transmitted radiofrequency field B1+ is a major factor hindering the image quality in Magnetic Resonance Imaging (MRI) at high field strengths. Here, a novel approach is presented, to locally modulate the B1+ utilizing…
In this contribution we present numerical and experimental results of a parametric quantitative study of radiative dipole antennas in a phased array configuration for efficient body magnetic resonance imaging at 7T via parallel…
Emerging concepts of metamaterials for MRI offer improved image quality through enhanced RF field control. However, current designs are often limited by bulky configurations, dielectric losses, and limited adaptability. Patient-specific…
Imaging of the human body at ultra-high fields (static magnetic field B0>7 Tesla) is challenging due to the radio-frequency field inhomogeneities in the human body tissues caused by the short wavelength. These effects could be partially…
Channel sounding is essential for the development of radio systems. One flexible strategy is the switched-array-based channel sounding, where antenna elements are activated at different time instants to measure the channel spatial…
At optical frequencies, interactions of the electric field component of light with matter are dominating, whereas magnetic dipole transitions are inherently weak and challenging to access independently from electric dipole transitions.…
Purpose: Universal Pulses (UPs) are excitation pulses that reduce the flip angle inhomogeneity in high field MRI systems without subject-specific optimization, originally developed for parallel transmit (PTX) systems at 7T. We investigated…
Purpose The goal of this work is to develop and evaluate a single-layer tight-fit 32-element double-tuned loop/dipole transceiver (TxRx) array for human brain 31P MRS at 9.4T, achieving reasonable transmit and receive performance and…
In near-field beam focusing for finite-sized arrays, focal shift is a non-negligible issue. The actual focal point often appears closer to the array than the predefined focal distance, significantly degrading the focusing performance of…
Objective: To develop and evaluate a bore-integrated patch antenna array designed for whole-body excitation in ultra-high-field (UHF) magnetic resonance imaging (MRI) with improved transmit efficiency and address the limitations of existing…
This paper proposes a reconfigurable bidirectional array antenna with high-efficiency radiations and flexible beam-switching capability by employing a novel transmit-reflect switchable metasurface (TRSM). To realize the electromagnetic (EM)…
A large intelligent surface (LIS) is a promising approach to enhancing 6G performance in sub-10 GHz frequency bands. An analysis of the horizontal dipole linear array reveals that when the array size is sufficiently large, employing the…
This study presents a novel discretely dielectric material-coated (DDMC) dipole antenna design for ultra-high-field (UHF) MRI applications. This design improves frequency tuning, lowers electric field intensity, and reduces SAR by including…
The majority of atomic nuclei have deformed shapes and nearly all these shapes are symmetric with respect to reflection. There are only a few reflection asymmetric pear-shaped nuclei that have been found in actinide and lanthanide regions,…
We theoretically demonstrate that a dipole layer on the electrode can modulate the transmission properties of nanoscale devices by influencing the contact properties, through first principles simulations on carbon nanotube based field…
Ultra-high field MRI offers unprecedented detail for non-invasive visualization of the human brain. However, brain imaging is challenging at 7T due to the B$_1^+$ field inhomogeneity, which results in signal intensity drops in temporal…
Each single domain nano-magnet acts as a magnetic dipole in addition it oscillates its magnetization about the easy axis and rotates coherently depending upon temperature and anisotropy. In an ensemble of nano-magnets, the relaxation time…
Directional modulation (DM) is a physical layer security technique based on antenna arrays and so far the polarisation information has not been considered in its designs. To increase the channel capacity, we consider exploiting the…
Transmitter arrays play a critical role in ultra high field Magnetic Resonance Imaging (MRI), especially given the advantages made possible via parallel transmission (pTx) techniques. One of the challenges in design and construction of…