A navigator echo is acquired during imaging, and when frequency is corrected based on phase change, the correction is performed with high accuracy without being affected by an offset caused by variations with time. An MRI apparatus including a navigation controller is configured to control an imaging unit acquiring an NMR signal, generate the navigator echo and collect navigation data during a predetermined measurement time, prior to collection of nuclear magnetic resonance signals for reconstructing an image of a subject. The phase change of the navigator echo is analyzed during the measurement time to calculate a correction value for correcting misalignment due to the phase change with a navigation analyzer that calculates a phase change amount relative to a reference, based on a difference between the phase change of the navigator echo and the phase change of the navigator echo serving as the reference during the measurement time.

A radio-frequency power converter and a radio-frequency transmission system for magnetic resonance imaging are provided in embodiments of the present invention. The radio-frequency power converter comprises a printed circuit board, the printed circuit board comprises a first circuit layer, a ground layer, and one or a plurality of intermediate layers located between the first circuit layer and the ground layer. A plurality of planar spiral inductors connected in parallel are formed on the first circuit layer. One ends of the plurality of inductors are connected to each other and respectively connected to one end of a first capacitor, the other ends of the plurality of inductors are respectively connected to one ends of a plurality of second capacitors, and the other ends of the plurality of second capacitors are all grounded.

A system for scanning an object is provided. The system may include: a supporting table configured to support the object; a first signal conversion unit configured to receive one or more first signals associated with the object and convert the first signals into one or more second signals; and a second signal receiver board configured to receive the one or more second signals. The first signal conversion unit may include a plurality of first signal receiving channels. Each first signal receiving channel may be configured to receive a first signal associated with a portion of the object. The supporting table and the second signal receiver board may be configured to move relative to each other to cause the second signal receiver board to receive at least one second signal corresponding to at least one first signal received by at least one target channel of the first signal receiving channels.

A local coil for an MRI scanner, an MRI scanner and a method for operating the MRI scanner are provided. The local coil includes a plurality of n antenna coils and at least one analog-to-digital converter having a signal link to the antenna coils. The local coil includes a compression device configured to compress the n digital input data streams into m digital output data streams. The n digital input data streams are mapped to an m-dimensional space with m base vectors.

A magnetic resonance coil and a magnetic resonance imaging system using the same are provided. The magnetic resonance coil may include an antenna, an amplifier, and a protective circuit. The antenna may be configured to receive a radio frequency (RF) signal emitted from an object. The antenna may not resonate with the RF signal. The amplifier operably coupled to the antenna configured to amplify the RF signal. The protective circuit may be configured to protect the antenna and the amplifier.

A distributed device and method for detecting groundwater based on nuclear magnetic resonance are provided. The device includes an excitation apparatus, multiple polarization apparatuses, an aerial reception apparatus, and a control apparatus. The aerial reception apparatus includes an array cooled coil sensor. For each of the multiple polarization apparatuses, a position analysis module determines, together with a second position analysis module of the polarization apparatus, a position of the array cooled coil sensor relative to a polarization coil in the polarization apparatus. A polarization transmitter in the polarization apparatus switches to a mode of waiting for output in a case that the array cooled coil sensor is in coverage of the polarization coil. The polarization transmitter in the polarization apparatus remains in a standby mode in a case that the array cooled coil sensor is beyond coverage of the polarization coil.

Various approaches of amplifying an NMR signal in response to a transmitted NMR pulse include estimating the characteristic time associated with the NMR signal; transmitting the NMR pulse to the sample and receiving the NMR signal therefrom; and applying a time-dependent amplifier gain to the received NMR signal based at least in part on the estimated characteristic time.

Storage medium, magnetic resonance apparatus and method for obtaining a magnetic resonance dataset including a pilot signal uses a magnetic resonance sequence. The pilot signal is generated at a first frequency range, and a magnetic resonance signal is generated at a second frequency range. The pilot signal and the magnetic resonance signal are acquired simultaneously. At least one parameter, in particular the phase and/or the frequency range, of the pilot signal is changed during the execution of the magnetic resonance sequence at least once.

A measurement device for measuring MR signals in a MR device may include first and second magnetometers and a controller. The first magnetometer may be a quantum spin magnetometer that includes a sensor material having a spin defect center including Zeeman splitting states dependent on an external magnetic field of the MR device, an optical excitation source and a microwave excitation source for electromagnetically exciting the sensor material, and a measurement sensor for measuring optical signals emitted by the excited sensor material element and depending on the Zeeman splitting states. The controller may be configured to determine a working frequency of the microwave excitation source of the first magnetometer from the total magnetic field strength measured by the second magnetometer, and control the microwave excitation source to use the determined working frequency as microwave frequency, such that the first magnetometer measures the MR signals as the optical signal.

A magnetic resonance imaging system (100) comprising a main magnet (104) for generating a main magnetic field within an imaging zone (108); a radio frequency, RF, antenna (114), comprising an RF input terminal (300) and an RF output terminal (302); an RF system for supplying radio-frequency power to the RF input terminal (300) to energize the antenna (114), the antenna (114) being further adapted for picking up magnetic resonance signals (144) from the imaging zone (108); a data acquisition system (126) for receiving the magnetic resonance signals (144) from the RF output terminal (302); wherein the RF input terminal (300) is in galvanic connection to the antenna (114) and the RF output terminal (302) is inductively coupled to the antenna (114).