A radio frequency (RF) system comprises an RF-array of antenna elements, a regulating arrangement to tune the antenna elements' impedances and a camera system to acquire image information of the RF-array. An analysis module is provided to derive operational settings such as resonant tuning settings, decoupling and impedance matchings of the antenna elements' impedances from the image information. The image information also represents the actual impedances and resonant properties of the RF-array. From the image information appropriate impedance settings can be derived that are the tuning parameters to render the RF-array resonant.

The exemplary system and method facilitate excitation of RF magnetic fields in ultra-high field (UHF) magnetic resonance (MRI) systems (e.g., MRI/NMR system) using a slotted waveguide array (SWGA) as an exciter coil. The exemplary exciter coil, in some embodiments, is configurable to provide RF magnetic field B.sub.1.sup.+ with high field-uniformity, with high efficiency, with excellent circular polarization, with negligible axial z-component, with arbitrary large field of view, and with exceptional possibilities for field-optimizations via RF shimming.

A head coil apparatus for MRI of a person's head includes a transmit coil array device generating RF fields for spin state excitation to the head, wherein the transmit coil array device comprises multiple transmit coil loops decoupled from each other and arranged on a transmit coil array carrier surrounding an inner head coil space for receiving the head; a receive coil array device for receiving RF resonance signals from the head; a RF shield surrounding the transmit coil array device and the receive coil array device; and a head coil window providing a viewing port through the RF shield and transmit coil array device. The head coil window has a longitudinal extension and an azimuthal extension, the transmit coil loops includes a window coil loop surrounding the head coil window, and the coil loop is decoupled from a neighbouring transmit coil loop by sharing a common loop conductor.

Various embodiments of the present disclosure are directed towards a magnetic resonance imaging (MRI) radio frequency (RF) coil configured to operate in at least one of a transmit mode or a receive mode. A first birdcage coil includes a pair of first-birdcage end rings and at least four first-birdcage rungs circumferentially arranged along the first-birdcage end rings. A second birdcage coil including a pair of second-birdcage end rings and at least four second-birdcage rungs circumferentially arranged along the second-birdcage end rings. The first and second birdcage coils neighbor and are spaced by a first non-zero distance along an axis. The axis is surrounded by the first-birdcage end rings and the second-birdcage end rings, and the first non-zero distance is greater than individual lengths of the first and second birdcage coils along the axis.

A method of operating a multi-coil magnetic resonance imaging system, is disclosed which includes establishing initial circuit values of a drive circuit, loading a tissue model associated with a tissue to be imaged, loading target values for a variable of interest (VOI) associated with operation of two or more coils of a magnetic resonance imaging system, performing a simulation based on the established circuit values and the loaded tissue model, determining output values of the VOI based on the simulation, comparing the simulated output values of the VOI to the loaded target values of the VOI, if the simulated output values are outside of a predetermined envelope about the loaded target values of the VOI, then performing a first optimization until the simulated output values are within the predetermined envelope.

A radio frequency coil according to an embodiment is configured to receive a magnetic resonance signal from an examined subject. The radio frequency coil includes an expandable and contractible first element and an expandable and contractible second element. The radio frequency coil has an overlap region where a first loop formed by the first element overlaps with a second loop formed by the second element. The ratio of the area of the overlap region to the area of the region enclosed by the first loop changes in accordance with expansion/contraction of the first element forming the first loop. The first element and the second element include liquid metal in at least a part thereof.

An array coil according to an embodiment includes a plurality of element coils, a first electrically-insulative coupler, and a second electrically-insulative coupler. Each of the plurality of element coils has a first fixation point and a second fixation point. The plurality of element coils are two-dimensionally arrayed in a first direction and a second direction while overlapping one another. The first electrically-insulative coupler is configured to couple together two or more of the first fixation points in the first direction. The second electrically-insulative coupler is configured to couple together two or more of the second fixation points in the first direction.

Various embodiments of the present disclosure are directed towards a magnetic resonance imaging (MRI) radio frequency (RF) coil configured to operate in at least one of a transmit mode or a receive mode. A first birdcage coil includes a pair of first-birdcage end rings and at least four first-birdcage rungs circumferentially arranged along the first-birdcage end rings. A second birdcage coil including a pair of second-birdcage end rings and at least four second-birdcage rungs circumferentially arranged along the second-birdcage end rings. The first and second birdcage coils neighbor and are spaced by a first non-zero distance along an axis. The axis is surrounded by the first-birdcage end rings and the second-birdcage end rings, and the first non-zero distance is greater than individual lengths of the first and second birdcage coils along the axis.

The present disclosure relates to a magnetic resonance imaging (MRI) radio frequency (RF) array coil that includes first and second physical RF coils inductively coupled. A first matching circuit and a second matching circuit are coupled to the first physical RF coil and the second physical RF coil, respectively, and are coupled in a parallel configuration at a first RF port. A third matching circuit and a fourth matching circuit are coupled to the first physical RF coil and the second physical RF coil, respectively, and are coupled in an anti-parallel configuration at a second RF port. A first logical RF coil is formed by the first and second physical RF coils and the first and second matching circuits. A second logical RF coil, which is decoupled from the first logical RF coil, is formed by the first and second physical RF coils and the third and fourth matching circuits.

The disclosure relates to a magnetic resonance imaging device configured to exert a high-frequency electromagnetic field on an object under test in a static magnetic field and to reconstruct an image based on magnetic resonance signals. The magnetic resonance imaging device comprises a receiving coil comprising a plurality of receiving coil elements and configured to receive magnetic resonance signals and feed the magnetic resonance signals to a receiver, and a coupler configured to be coupled with at least a first receiving coil element of the receiving coil, the coupler being directionally coupled with at least the receiver, the first receiving coil element being configured to receive a high-frequency electromagnetic wave signal through the coupler. The directional coupling between the coupler and the receiver is so regulated that the first receiving coil element transmits the high-frequency electromagnetic wave signal to the object under test to sense a physiological movement signal.