The present disclosure relates to a radio-frequency coil for a magnetic resonance device, comprising: antenna units, conductor end ring segments connecting the antenna units, and capacitors. Here, a single antenna unit is curved in a plane parallel to a direction of a static magnetic field B.sub.0 (the positive direction of the z axis); the cross sections of all the antenna units in a x-y plane are spaced apart from each other at an angle and distributed symmetrically in a radial array; adjacent antenna units are connected with the end ring segments and the capacitors at two ends; the coil as a whole is an open dome shape surface structure and is sufficiently conformal to the surface of an object to be scanned.

The present disclosure relates to a multi-channel magnetic resonance imaging RF coil (114) with at least four channels and comprising a coil element for each of the channels, the RF coil (114) further comprising for each coil element a socket (300-306) that is electrically coupled to said coil element via a respective first transmission line (209), each socket (300-306) being adapted for receiving a plug for providing an RF signal via the respective first transmission line (209) to the respective coil element, wherein with respect to a predefined RF signal the differences in electrical length between any of the transmission lines is k/4 where k is an integer and is the wavelength of the RF signal.

Signals of interest in magnetic resonance imaging (MRI) systems comprise narrowband, circularly polarized (CP) radio-frequency magnetic fields from rotating atomic nuclei. Background body noise may comprise broadband, linearly polarized (LP) magnetic fields from thermally-activated eddy currents, and may exceed the signal in a band of interest, limiting the imaging resolution and requiring excessive averaging times. Noise may be selectively detected and substantially suppressed, while enhancing the signal of interest, using appropriate digital time-domain algorithms. At least two quadrature receiving antennas may be employed to distinguish and separate the LP noise from the CP signal. At least one broadband receiver may be used to identify and localize fast noise sources and to digitally filter the representation of their radio-frequency magnetic fields in the signal. Selective body noise reduction may allow enhanced signal-to-noise ratio of the system, leading to improved imaging resolution and shorter scan time.

Nuclear magnetic resonance (MR) imaging can include use of an electrical transceiver coil system comprising an array of segmented loops. The array can be arranged about a portion of an imaging subject and arranged to provide surgical access to a region of the imaging subject from at least one direction. The segmented loops can establish a volumetric radio frequency (RF) excitation field across a volume-of-interest associated with the imaging subject in response to the segmented loops receiving specified transmit phases providing a non-90-degree relative phase between segmented coil loops at adjacent ones of the segmented loops. All or at least some of the segmented loops can provide outputs indicative of an RF signal from the imaging subject, the RF signal elicited in response to RF excitation. The transceiver coil system can facilitate pre-operative, intra-operative, or post-operative MR imaging, such as facilitating access for a surgical procedure.

A magnetic resonance (MR) system includes a volume-type radio-frequency (RF) coil assembly having a volume coil with a plurality of ports and a ring coil with a plurality of ports (p) and which is situated about the volume-type coil. At least one controller is configured to selectively control a first transmit/receive (T/R) radio frequency (RF) channel to generate an output including RF quadrature signals to drive the volume-type coil and to selectively control a second T/R RF channel to generate an output including RF quadrature signals to drive the ring coil.

Embodiments relate to magnetic resonance imaging (MRI) radio frequency (RF) coil arrays. One example coil array comprises: at least one row of RF coil elements arranged radially around a cylindrical axis, wherein each row comprises: at least four RF coil elements circumferentially enclosing the cylindrical axis, wherein each RF coil element of that row is configured to operate in a Tx mode and in a Rx mode, wherein, in the Rx mode, each RF coil element of that row is tuned to a working frequency of the MRI RF coil array, and wherein, in the Tx mode, each RF coil element of that row is tuned to an additional frequency that is different than the working frequency, wherein the additional frequency is such that, a mode frequency of a selected mode resulting from coupling among the RF coil elements of that row is at the working frequency.

A transmitting antenna for a magnetic resonance device includes a plurality of antenna conductors arranged spaced from one another circumferentially around a center line and extending parallel to the center line, and a screening element extending parallel to the center line and circumferentially encompassing the antenna conductors. For at least one pair of the antenna conductors, a radial distance between a first antenna conductor of the pair and the screening element is smaller than a radial distance between a second antenna conductor of the pair and the screening element, a width of the first antenna conductor is smaller in the circumferential direction than a width of the second antenna conductor in the circumferential direction, axial ends of the first antenna conductor are coupled together via a higher capacitance capacitor than axial ends of the second antenna conductor.

According to one embodiment, a magnetic resonance imaging apparatus includes a static field magnet, a gradient coil, at least one radio frequency coil, a receiver and processing circuitry. The static field magnet, the gradient coil, the at least one radio frequency coil and the receiver are configured to acquire magnetic resonance signals from an object. The processing circuitry is configured to generate magnetic resonance image data based on the magnetic resonance signals. The receiver is configured to convert analog magnetic resonance signals received by the at least one radio frequency coil into digital magnetic resonance signals without a downconversion; separate the digital magnetic resonance signals into in-phase signals and quadrature-phase signals; and perform filter processing for removing noises of the in-phase signals and the quadrature-phase signals.

In order to provide interventional access during an image-guided interventional procedure, while increasing the signal-to-noise ratio for generated images compared to a single loop coil, a local coil includes a single coil element disposed around an opening through the local coil and two coil elements positioned on opposite sides of the single coil element. The opening provides access for an interventional tool used during the image-guided interventional procedure.

Here we present a solid-state spin sensor with enhanced sensitivity. The enhanced sensitivity is achieved by increasing the T.sub.2* dephasing time of the color center defects within the solid-state spin sensor. The T.sub.2* dephasing time extension is achieved by mitigating dipolar coupling between paramagnetic defects within the solid-state spin sensor. The mitigation of the dipolar coupling is achieved by applying a magic-angle-spinning magnetic field to the color center defects. This field is generated by driving a magnetic field generator (e.g., Helmholtz coils) with phase-shifted sinusoidal waveforms from current source impedance-matched to the magnetic field generator. The waveforms may oscillate (and the field may rotate) at a frequency based on the precession period of the color center defects to reduce color center defect dephasing and further enhance measurement sensitivity.