Magnetic resonance imaging scanner and magnetic resonance imaging system

Abstract

This application provides a magnetic resonance imaging scanner and a magnetic resonance imaging system, belonging to the field of electronic technology. The magnetic resonance imaging scanner includes an RF coil, a gradient coil unit, a pulse sequence unit, a high-voltage transmitting unit, a low-noise receiving unit, a gradient control unit, and a switching unit. The first terminal of the pulse sequence unit is connected to the microcontroller unit; the second and third terminals of the pulse sequence unit are connected to the first and second terminals of the high-voltage transmitting unit, respectively; the fourth terminal of the pulse sequence unit is connected to the first terminal of the low-noise receiving unit and the switching unit; the fifth terminal of the pulse sequence unit is connected to the first and second terminals of the low-noise receiving unit, respectively; and the sixth terminal of the pulse sequence unit is connected to the first terminal of the gradient control unit. The second terminal of the gradient control unit is connected to the gradient coil unit, and the first and second terminals of the RF coil are connected to the fourth and fifth terminals of the high-voltage transmitting unit, respectively. This application enables the miniaturization of the magnetic resonance imaging scanner.

Description

Technical Field

[0001] This application relates to the field of electronic technology, and more specifically, to a magnetic resonance imaging scanner and a magnetic resonance imaging system. Background Technology

[0002] With the development of science and technology, magnetic resonance imaging (MRI) technology has also made great strides. MRI technology can be applied in fields such as medicine and chemical analysis. Specifically, by detecting the radio frequency (RF) field generated by non-zero spin nuclei, the internal three-dimensional (3D) structure of an object can be non-invasively depicted to identify the object's morphological features without ionizing radiation.

[0003] Traditional MRI scanners are typically equipped with superconducting magnets with a magnetic field of approximately 1 terahertz (T) or higher to magnetize the atomic nuclei of the object being examined. They also employ discrete electronic components, such as transmitters for radio frequency excitation, receivers for receiving resonance signals, and programmers for implementing software functions. The resonance signals are then analyzed by computer equipment to generate resonance spectra, thus providing high spatial and temporal resolution.

[0004] However, the large size of the components in traditional MRI scanners results in a significant space requirement, making it difficult to perform MRI scans in confined spaces. Therefore, miniaturization of MRI scanners has become an urgent problem to be solved. Summary of the Invention

[0005] The purpose of this application is to provide a magnetic resonance imaging scanner and a magnetic resonance imaging system that enable the miniaturization of the magnetic resonance imaging scanner.

[0006] The embodiments of this application are implemented as follows:

[0007] A first aspect of this application provides a magnetic resonance imaging scanner, including a radio frequency coil, a gradient coil unit, and an integrated circuit, wherein the integrated circuit includes a pulse sequence unit, a high-voltage transmitting unit, a low-noise receiving unit, a gradient control unit, and a switching unit;

[0008] The first terminal of the pulse sequence unit is used to connect to the microcontroller unit (MCU). The second and third terminals of the pulse sequence unit are connected to the first and second terminals of the high-voltage transmitting unit, respectively. The fourth terminal of the pulse sequence unit is connected to the first terminal of the low-noise receiving unit and to the switching unit. The fifth terminal of the pulse sequence unit is connected to the first and second terminals of the low-noise receiving unit, respectively. The sixth terminal of the pulse sequence unit is connected to the first terminal of the gradient control unit.

[0009] The third terminal of the high-voltage transmitting unit is used to input radio frequency signals of different phases. The fourth and fifth terminals of the high-voltage transmitting unit are respectively connected to the third and fourth terminals of the low-noise receiving unit through the switching unit. The fifth and sixth terminals of the low-noise receiving unit are respectively used to connect to the microcontroller unit. The second terminal of the gradient control unit is connected to the gradient coil unit. The first and second terminals of the radio frequency coil are respectively connected to the fourth and fifth terminals of the high-voltage transmitting unit.

[0010] The pulse sequence unit is used to generate and output pulse signals; the high-voltage transmitting unit is used to adjust the radio frequency pulses output to the radio frequency coil under the action of the pulse signals and the radio frequency signals.

[0011] The gradient control unit is used to control the gradient coil unit to output gradient magnetic field signals in different directions under the action of pulse signals;

[0012] The low-noise receiving unit is used to receive and amplify the sampling signal output by the radio frequency coil under the action of a pulse signal, and output the amplified sampling signal to the microcontroller unit.

[0013] Optionally, the gradient coil unit includes a gradient coil driver and a gradient coil;

[0014] The first end of the gradient coil driver is connected to the second end of the gradient control unit, and the second end of the gradient coil driver is connected to the gradient coil.

[0015] The gradient coil driver is used to output a corresponding operating voltage to the gradient coil under the control of the gradient control unit, so that the gradient coil outputs each gradient magnetic field signal.

[0016] Optionally, the high-voltage transmitting unit includes a high-voltage power amplifier array, a first digital-to-analog converter (DAC), a phase shifter, and a phase selector;

[0017] The first terminal of the phase selector is used to input each of the radio frequency signals, the second terminal of the phase selector is connected to the second terminal of the pulse sequence unit, the third terminal of the phase selector is connected to the first terminal of the phase shifter, and the fourth and fifth terminals of the phase selector are respectively connected to the seventh and eighth terminals of the low noise receiving unit.

[0018] Each second terminal of the phase shifter is connected to each first terminal of the high-voltage power amplifier array, each first terminal of the first digital-to-analog converter is connected to the third terminal of the pulse sequence unit, and each second terminal of the first digital-to-analog converter is connected to each second terminal of the high-voltage power amplifier array.

[0019] The third and fourth terminals of the high-voltage power amplifier array are respectively connected to the third and fourth terminals of the low-noise receiving unit.

[0020] The phase selector is used to determine the target radio frequency signal from each of the radio frequency signals and output it to the phase shifter, and to output a corresponding reference signal to the low noise receiving unit according to the target radio frequency signal. The phase selector is also used to realize phase modulation under the action of the first pulse signal.

[0021] The first digital-to-analog converter is used to achieve amplitude modulation under the action of the second pulse signal and output analog voltage to the high-voltage power amplifier array;

[0022] The high-voltage power amplifier array is used to adjust the radio frequency pulse output to the radio frequency coil under the action of the target radio frequency signal and the analog voltage.

[0023] Optionally, the high-voltage power amplifier array includes multiple high-voltage power amplifiers, all of which are connected in parallel and have the same parameters.

[0024] Each of the aforementioned high-voltage power amplifiers includes a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a first capacitor, a second capacitor, a first inductor, and a second inductor.

[0025] Optionally, the first terminal of the first inductor and the second terminal of the second inductor are respectively used to input the operating voltage;

[0026] The second end of the first inductor is connected to the first plate of the first capacitor and the drain of the first switching transistor, respectively. The second plate of the first capacitor is connected to the first end of the radio frequency coil, and the source of the first switching transistor is connected to the drain of the second switching transistor.

[0027] The second end of the second inductor is connected to the first plate of the second capacitor and the drain of the third switching transistor, the second plate of the second capacitor is connected to the second end of the radio frequency coil, and the source of the third switching transistor is connected to the drain of the fourth switching transistor.

[0028] The gates of the first and third switching transistors are respectively connected to the second terminal of the first digital-to-analog converter, and the gates of the second and fourth switching transistors are respectively connected to the second terminal of the phase shifter.

[0029] The source of the third switch and the source of the fourth switch are grounded.

[0030] Optionally, the low-noise receiving unit includes a low-noise amplifier (LNA), a first filtering subunit, and a second filtering subunit;

[0031] The first and second terminals of the low-noise amplifier are respectively connected to the fourth and fifth terminals of the high-voltage transmitting unit, and the third terminal of the low-noise amplifier is respectively connected to the first terminal of the first filter subunit and the first terminal of the second filter subunit.

[0032] The fourth terminal of the low-noise amplifier is connected to the second terminal of the first filter subunit and the second terminal of the second filter subunit, respectively.

[0033] The third terminal of the first filter subunit is connected to the fourth terminal of the phase selector, and the third terminal of the second filter subunit is connected to the fifth terminal of the phase selector.

[0034] The fourth terminal of the first filtering subunit is connected to the second terminal of the microcontroller unit, and the fourth terminal of the second filtering subunit is connected to the third terminal of the microcontroller unit.

[0035] Optionally, the first filtering subunit includes a first mixer, a first operational amplifier, and a first low-pass filter;

[0036] The first and second terminals of the first mixer are connected to the third and fourth terminals of the low-noise amplifier, respectively. The third terminal of the first mixer is connected to the fourth terminal of the phase selector. The fourth and fifth terminals of the first mixer are connected to the first and second terminals of the first operational amplifier, respectively.

[0037] The third terminal of the first operational amplifier is connected to the first terminal of the first low-pass filter, and the second terminal of the first low-pass filter is connected to the second terminal of the microcontroller unit.

[0038] The second filtering subunit includes a second mixer, a second operational amplifier, and a second low-pass filter;

[0039] The first and second terminals of the second mixer are connected to the third and fourth terminals of the low-noise amplifier, respectively. The third terminal of the second mixer is connected to the fifth terminal of the phase selector. The fourth and fifth terminals of the second mixer are connected to the first and second terminals of the second operational amplifier, respectively.

[0040] The third terminal of the second operational amplifier is connected to the first terminal of the second low-pass filter, and the second terminal of the second low-pass filter is connected to the third terminal of the microcontroller unit.

[0041] Optionally, the pulse sequence unit includes a memory, a pulse programmer, and a coordinator;

[0042] The first end of the memory is connected to the first end of the microcontroller, the second and third ends of the memory are connected to the first and second ends of the pulse programmer, respectively, and the third end of the memory is connected to the first end of the coordinator.

[0043] The second terminal of the pulse programmer is connected to the second terminal of the coordinator, the third terminal of the coordinator is connected to the first terminal of the gradient control unit, the fourth and fifth terminals of the coordinator are connected to the first and second terminals of the high-voltage transmitting unit, respectively, the sixth and seventh terminals of the coordinator are connected to the first and second terminals of the low-noise receiving unit, respectively, and the eighth terminal of the coordinator is used to input an enable signal.

[0044] The memory is used to receive and store the pulse commands output by the microcontroller unit;

[0045] The pulse programmer is used to generate corresponding pulse signals according to the pulse instructions, and the coordinator is used to forward each pulse signal to the corresponding port.

[0046] Optionally, the gradient control unit includes a plurality of second digital-to-analog converters;

[0047] Each of the second digital-to-analog converters includes a two-stage operational amplifier with a ladder network;

[0048] Each of the second digital-to-analog converters is used to output a corresponding control signal to the gradient coil unit under the action of the third pulse signal, so that the gradient coil unit outputs the gradient magnetic field signal according to a preset time interval and a preset amplitude.

[0049] A second aspect of this application provides a magnetic resonance imaging system, the magnetic resonance imaging system comprising: a microcontroller unit, a radio frequency signal generation unit, and the magnetic resonance imaging scanner described in the first aspect above;

[0050] The microcontroller unit and the radio frequency signal generation unit are respectively connected to the magnetic resonance imaging scanner.

[0051] The beneficial effects of the embodiments of this application include:

[0052] This application provides a magnetic resonance imaging scanner, which includes a radio frequency coil, a gradient coil unit, and an integrated circuit. The integrated circuit includes a pulse sequence unit, a high-voltage transmitting unit, a low-noise receiving unit, a gradient control unit, and a switching unit.

[0053] The first end of the pulse sequence unit is used to connect to the microcontroller unit. The second and third ends of the pulse sequence unit are connected to the first and second ends of the high-voltage transmitting unit, respectively. The fourth end of the pulse sequence unit is connected to the first end of the low-noise receiving unit and to the switching unit. The fifth end of the pulse sequence unit is connected to the first and second ends of the low-noise receiving unit, respectively. The sixth end of the pulse sequence unit is connected to the first end of the gradient control unit.

[0054] The third terminal of the high-voltage transmitting unit is used to input radio frequency signals of different phases. The fourth and fifth terminals of the high-voltage transmitting unit are connected to the third and fourth terminals of the low-noise receiving unit through the switching unit, respectively. The fifth and sixth terminals of the low-noise receiving unit are used to connect to the microcontroller unit, respectively. The second terminal of the gradient control unit is connected to the gradient coil unit, and the first and second terminals of the radio frequency coil are connected to the fourth and fifth terminals of the high-voltage transmitting unit, respectively.

[0055] As can be seen, the pulse sequence unit, high-voltage transmission unit, low-noise receiving unit, gradient control unit, and switching unit are all integrated into the integrated circuit. This can significantly improve the integration of the circuits used to drive the radio frequency coil, gradient coil unit, and amplify the sampled signal in the magnetic resonance imaging scanner.

[0056] Furthermore, as can be seen from the working principle of the magnetic resonance imaging scanner, the magnetic resonance imaging scanner provided in this application embodiment does not require a large permanent magnet, nor does it require other large driving circuits and control circuits to achieve the function of magnetic resonance imaging. Moreover, it can accurately and reliably encode the atomic nuclei of the sampled object by outputting synchronous gradient magnetic field signals and radio frequency pulses, thereby ensuring the accuracy and reliability of magnetic resonance imaging.

[0057] This allows for the miniaturization of magnetic resonance imaging scanners while ensuring the accuracy and reliability of magnetic resonance imaging. Attached Figure Description

[0058] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 This is a schematic diagram of the structure of a first magnetic resonance imaging scanner provided in an embodiment of this application;

[0060] Figure 2 This is a schematic diagram of the structure of a second magnetic resonance imaging scanner provided in an embodiment of this application;

[0061] Figure 3 This is a schematic diagram of the structure of a third magnetic resonance imaging scanner provided in an embodiment of this application;

[0062] Figure 4 This is a schematic diagram of the structure of the fourth magnetic resonance imaging scanner provided in the embodiments of this application;

[0063] Figure 5 This is a schematic diagram of the structure of the fifth magnetic resonance imaging scanner provided in the embodiments of this application;

[0064] Figure 6 This is a schematic diagram of the structure of the sixth magnetic resonance imaging scanner provided in the embodiments of this application;

[0065] Figure 7 A schematic diagram of the structure of the seventh magnetic resonance imaging scanner provided in the embodiments of this application;

[0066] Figure 8 This is a schematic diagram of the structure of the eighth magnetic resonance imaging scanner provided in the embodiments of this application;

[0067] Figure 9 This is a schematic diagram of the structure of a magnetic resonance imaging system provided in an embodiment of this application. Detailed Implementation

[0068] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0069] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0070] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0071] In the description of this application, it should be noted that the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0072] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0073] Traditional MRI scanners typically employ superconducting magnets of approximately 1 terabyte (T) or more to magnetize the atomic nuclei of the object being examined. They also utilize discrete electronic components, such as transmitters for radio frequency excitation, receivers for receiving resonance signals, and programmers for implementing software functions. The resonance signals are then analyzed by computer equipment to generate resonance spectra, thereby providing high spatial and temporal resolution.

[0074] However, the large size of the components in traditional MRI scanners results in a significant space requirement, making it difficult to perform MRI scans in confined spaces. Therefore, miniaturization of MRI scanners has become an urgent problem to be solved.

[0075] To address this, embodiments of this application provide a magnetic resonance imaging (MRI) scanner. This scanner incorporates a radio frequency (RF) coil, a gradient coil unit, and an integrated circuit. The integrated circuit includes a pulse sequence unit, a high-voltage transmitting unit, a low-noise receiving unit, a gradient control unit, and a switching unit. The first terminal of the pulse sequence unit is connected to a microcontroller unit. The second and third terminals of the pulse sequence unit are connected to the first and second terminals of the high-voltage transmitting unit, respectively. The fourth terminal of the pulse sequence unit is connected to the first terminal of the low-noise receiving unit and also to the switching unit. The fifth terminal of the pulse sequence unit is connected to both the first and second terminals of the low-noise receiving unit, respectively. The sixth terminal of the pulse sequence unit is connected to the first terminal of the gradient control unit. The third terminal of the high-voltage transmitting unit is used to input RF signals of different phases. The fourth and fifth terminals of the high-voltage transmitting unit are connected to the third and fourth terminals of the low-noise receiving unit, respectively, via the switching unit. The fifth and sixth terminals of the low-noise receiving unit are connected to the microcontroller unit. The second terminal of the gradient control unit is connected to the gradient coil unit. The first and second terminals of the RF coil are connected to the fourth and fifth terminals of the high-voltage transmitting unit, respectively. It can enable the miniaturization of magnetic resonance imaging scanners.

[0076] This application uses a magnetic resonance imaging scanner as an example for illustration. However, it does not imply that this application's embodiments can only be applied to magnetic resonance imaging.

[0077] The magnetic resonance imaging scanner provided in the embodiments of this application will be explained in detail below.

[0078] Figure 1 A schematic diagram of the structure of a magnetic resonance imaging scanner provided in this application. See also... Figure 1 This application provides a magnetic resonance imaging scanner, which includes an RF coil 101, a gradient coil unit 102, and an integrated circuit 103. The integrated circuit 103 includes a pulse sequence unit 104, a high-voltage transmitting unit 105, a low-noise receiving unit 106, a gradient control unit 107, and a switching unit 108.

[0079] The first terminal of the pulse sequence unit 104 is used to connect to the microcontroller unit. The second and third terminals of the pulse sequence unit 104 are connected to the first and second terminals of the high voltage transmitting unit 105, respectively. The fourth terminal of the pulse sequence unit 104 is connected to the first terminal of the low noise receiving unit 106 and to the switching unit 108. The fifth terminal of the pulse sequence unit 104 is connected to the first and second terminals of the low noise receiving unit 106, respectively. The sixth terminal of the pulse sequence unit 104 is connected to the first terminal of the gradient control unit 107.

[0080] The third terminal of the high-voltage transmitting unit 105 is used to input radio frequency signals of different phases. The fourth and fifth terminals of the high-voltage transmitting unit 105 are connected to the third and fourth terminals of the low-noise receiving unit 106 through the switching unit 108, respectively. The fifth and sixth terminals of the low-noise receiving unit 106 are used to connect to the microcontroller unit, respectively. The second terminal of the gradient control unit 107 is connected to the gradient coil unit 102. The first and second terminals of the radio frequency coil 101 are connected to the fourth and fifth terminals of the high-voltage transmitting unit 105, respectively.

[0081] The pulse sequence unit 104 can be used to generate and output pulse signals; the high voltage transmitting unit 105 is used to adjust the radio frequency pulses output to the radio frequency coil 101 under the action of the pulse signals and various radio frequency signals.

[0082] The gradient control unit 107 can be used to control the gradient coil unit 102 to output gradient magnetic field signals in different directions under the action of pulse signals.

[0083] The low-noise receiving unit 106 can be used to receive and amplify the sampling signal output by the radio frequency coil 101 under the action of a pulse signal, and output the amplified sampling signal to the microcontroller unit.

[0084] Optionally, the microcontroller unit can be a chip specifically designed to process the sampled signal, or it can be a processor in a computer device capable of performing operations such as calculation, processing, forwarding, and communication. This application embodiment does not limit this.

[0085] Each radio frequency signal can be generated by the radio frequency signal generation unit and output to the third terminal of the high voltage transmitting unit 105.

[0086] The radio frequency signal generating unit can be any device used to generate radio frequency signals, and this application embodiment does not limit it.

[0087] In addition, the radio frequency signal generation unit can generate and output multiple radio frequency signals of different phases simultaneously, or it can generate and output each radio frequency signal separately. This application embodiment does not limit this.

[0088] Optionally, the microcontroller unit can send corresponding pulse commands to the pulse sequence unit 104 via the Serial Peripheral Interface (SPI) to control the pulse sequence unit 104 to output corresponding pulse signals.

[0089] For example, the pulse sequence unit 104 may output a first pulse signal and a second pulse signal to the high voltage transmitting unit 105, a third pulse signal to the gradient control unit 107, and a fourth pulse signal to the low noise receiving unit 106 and / or the switching unit 108.

[0090] For example, the pulse sequence unit 104 can output the first pulse signal, the second pulse signal, the third pulse signal, and the fourth pulse signal based on a certain timing sequence. That is, the pulse sequence unit 104 outputs each pulse signal based on the pulse command output by the microcontroller unit.

[0091] The pulse command can be generated by the microcontroller according to actual needs, or it can be generated by the microcontroller under the operation of relevant technical personnel. The pulse command can also be used to indicate the amplitude and specific phase of each pulse signal, the time of the output pulse, the control word of the gradient control unit 107, and other information.

[0092] Furthermore, the attributes of the first pulse signal, the second pulse signal, the third pulse signal, and the fourth pulse signal may be the same or different, and this application embodiment does not limit this.

[0093] The switching unit 108 may include one or more controllable switches. Specifically, the fourth and fifth terminals of the high-voltage transmitting unit 105 are connected to the third and fourth terminals of the low-noise receiving unit 106 via these controllable switches. These controllable switches can be turned on or off under the control of the pulse signal output by the pulse sequence unit 104. When the controllable switch or the switching unit 108 is on, the low-noise receiving unit 106 can receive the sampled signal. This achieves the purpose of controlling whether to output the sampled signal to the low-noise receiving unit 106.

[0094] Optionally, the radio frequency pulse can be a voltage signal used to drive the radio frequency coil 101. Under the action of the radio frequency pulse, the radio frequency coil 101 can generate an excitation magnetic field corresponding to the radio frequency signal.

[0095] Optionally, the gradient control unit 107 can output a corresponding operating voltage to the gradient coil unit 102 under the action of a corresponding pulse signal, drive the gradient coil unit 102 to work, generate a corresponding magnetic field, and then output gradient magnetic field signals in different directions.

[0096] Each gradient magnetic field signal can be output at a specific time interval, and the amplitude of each gradient magnetic field signal corresponds to the pulse signal.

[0097] Each gradient magnetic field signal can provide an effective gradient magnetic field for the radio frequency coil 101, so that the excitation magnetic field generated after the radio frequency coil 101 works can be superimposed with each gradient magnetic field, thereby achieving the purpose of adjusting the magnetic field.

[0098] The high-voltage transmitting unit 105 adjusts the radio frequency pulse under the action of the pulse signal and various radio frequency signals. Specifically, it can adjust the phase, amplitude, duration and other attributes of the radio frequency pulse.

[0099] Optionally, the sampling signal is obtained by sampling the object to be sampled under the action of each gradient magnetic field signal.

[0100] In addition, in the magnetic resonance imaging scanner provided in this application embodiment, the gradient magnetic field signals are synchronized with the radio frequency pulses output by the high voltage transmitting unit 105 to the radio frequency coil 101. This ensures that the magnetic resonance imaging scanner can accurately and reliably spatially encode the atomic nuclei of the object to be sampled.

[0101] For example, each gradient magnetic field signal may include a first gradient magnetic field signal, a second gradient magnetic field signal, and a third gradient magnetic field signal, and the directions of the first gradient magnetic field signal, the second gradient magnetic field signal, and the third gradient magnetic field signal are perpendicular to each other.

[0102] For example, this first gradient magnetic field signal can correspond to the gradient magnetic field in the first direction, denoted by G. X This second gradient magnetic field signal corresponds to the gradient magnetic field in the second direction, denoted by G. y This is represented by G. The third gradient magnetic field signal can correspond to a third upward gradient magnetic field. z The plane formed by the first direction and the second direction can be parallel to the ground, and the plane formed by the first direction and the third direction, and the plane formed by the second direction and the third direction can be perpendicular to the ground. This application does not limit this.

[0103] Generally, the time for outputting the third gradient magnetic field signal is shorter than the time for outputting the first or second gradient magnetic field signal, and the time for outputting the third gradient magnetic field signal is generally 10-100μs.

[0104] Optionally, the low-noise receiving unit 106 may also filter the sampled signal.

[0105] It is worth noting that when it is necessary to perform magnetic resonance detection or magnetic resonance imaging on the object to be sampled, the object can be placed in the radio frequency coil 101. Then, under the control of the microcontroller unit, the pulse sequence unit 104 starts to output corresponding pulse signals to the high voltage transmitting unit 105, the low noise receiving unit 106, the gradient control unit 107, and the switching unit 108, at which point the magnetic resonance imaging scanner enters the working state.

[0106] It is worth noting that the principle of this magnetic resonance imaging scanner is as follows: the gradient control unit 107 outputs a corresponding operating voltage to the gradient coil unit 102 based on the received pulse signal. The gradient coil unit 102 outputs various gradient magnetic field signals, generating corresponding gradient magnetic fields. Meanwhile, the high-voltage transmitting unit 105 starts outputting radio frequency pulses based on the received radio frequency signals and pulse signals. Then, the radio frequency coil 101 operates under the action of these radio frequency pulses to generate an excitation magnetic field. Since the directions of the gradient magnetic fields are different, the directions and positions of the superposition of the gradient magnetic fields and the excitation magnetic field are also different. The gradient magnetic field signals are synchronized with the radio frequency pulses, thus enabling spatial encoding. Furthermore, when the object to be sampled is placed in the radio frequency coil 101, the atomic nuclei of the object will resonate in the magnetic field superimposed by the gradient magnetic fields and the excitation magnetic field. The radio frequency coil 101 then collects the corresponding sampling signals based on the resonance of the atomic nuclei and outputs them to the low-noise receiving unit 106.

[0107] The low-noise receiving unit 106 then amplifies and filters the sampled signal and outputs the amplified sampled signal to the microcontroller unit. The microcontroller unit then analyzes and processes each amplified sampled signal and generates a magnetic resonance image of the object to be sampled based on the amplified sampled signal. In this way, the function of magnetic resonance imaging can be realized.

[0108] In this embodiment of the application, a radio frequency coil 101, a gradient coil unit 102, and an integrated circuit 103 are provided in a magnetic resonance imaging scanner. The integrated circuit 103 includes a pulse sequence unit 104, a high voltage transmitting unit 105, a low noise receiving unit 106, a gradient control unit 107, and a switching unit 108.

[0109] The first terminal of the pulse sequence unit 104 is used to connect to the microcontroller unit. The second and third terminals of the pulse sequence unit 104 are connected to the first and second terminals of the high voltage transmitting unit 105, respectively. The fourth terminal of the pulse sequence unit 104 is connected to the first terminal of the low noise receiving unit 106 and to the switching unit 108. The fifth terminal of the pulse sequence unit 104 is connected to the first and second terminals of the low noise receiving unit 106, respectively. The sixth terminal of the pulse sequence unit 104 is connected to the first terminal of the gradient control unit 107.

[0110] The third terminal of the high-voltage transmitting unit 105 is used to input radio frequency signals of different phases. The fourth and fifth terminals of the high-voltage transmitting unit 105 are connected to the third and fourth terminals of the low-noise receiving unit 106 through the switching unit 108, respectively. The fifth and sixth terminals of the low-noise receiving unit 106 are used to connect to the microcontroller unit, respectively. The second terminal of the gradient control unit 107 is connected to the gradient coil unit 102. The first and second terminals of the radio frequency coil 101 are connected to the fourth and fifth terminals of the high-voltage transmitting unit 105, respectively.

[0111] As can be seen, the pulse sequence unit 104, the high voltage transmitting unit 105, the low noise receiving unit 106, the gradient control unit 107, and the switching unit 108 are all integrated in the integrated circuit 103. In this way, the integration of the circuit used to drive the radio frequency coil 101, the gradient coil unit 102, and amplify the sampled signal in the magnetic resonance imaging scanner can be greatly improved.

[0112] Furthermore, as can be seen from the working principle of the magnetic resonance imaging scanner, the magnetic resonance imaging scanner provided in this application embodiment does not require a large permanent magnet, nor does it require other large driving circuits and control circuits to achieve the function of magnetic resonance imaging. Moreover, it can accurately and reliably encode the atomic nuclei of the sampled object by outputting synchronous gradient magnetic field signals and radio frequency pulses, thereby ensuring the accuracy and reliability of magnetic resonance imaging.

[0113] This allows for the miniaturization of magnetic resonance imaging scanners while ensuring the accuracy and reliability of magnetic resonance imaging.

[0114] In one possible implementation, see [link to relevant documentation]. Figure 2 The gradient coil unit 102 includes a gradient coil driver 1021 and a gradient coil 1022.

[0115] The first end of the gradient coil driver 1021 is connected to the second end of the gradient control unit 107, and the second end of the gradient coil driver 1021 is connected to the gradient coil.

[0116] The gradient coil driver 1021 is used to output a corresponding operating voltage to the gradient coil 1022 under the control of the gradient control unit 107, so that the gradient coil 1022 outputs each gradient magnetic field signal.

[0117] Optionally, the gradient coil driver 1021 can be a device that outputs a large current to the gradient coil 1022 based on the voltage output by the gradient control unit 107. The gradient coil driver 1021 can be a device for voltage conversion, or it can be a device that integrates voltage conversion and power supply functions; this application embodiment does not limit this.

[0118] Optionally, the gradient coil 1022 can output gradient magnetic field signals in different directions and generate gradient magnetic fields in different directions.

[0119] Furthermore, the gradient magnetic fields generated by the gradient coil 1022 can be linear gradient magnetic fields, which can improve the stability of the gradient coil unit 102, thereby improving the accuracy and stability of the sampled signal and enhancing the effect of magnetic resonance imaging.

[0120] It is worth noting that the magnetic field strength acting on the sampled object can be adjusted by the gradient magnetic fields generated by the gradient coil 1022. If a larger magnetic field can be obtained by superimposing the gradient magnetic field with the excitation magnetic field, then there is no need to use a bulky permanent magnet, thus enabling the miniaturization of the magnetic resonance imaging scanner.

[0121] In one possible implementation, see [link to relevant documentation]. Figure 3 The high-voltage transmitting unit 105 includes a high-voltage power amplifier array 1051, a first digital-to-analog converter 1052, a phase shifter 1053, and a phase selector 1054.

[0122] The first terminal of the phase selector 1054 is used to input various radio frequency signals. The second terminal of the phase selector 1054 is connected to the second terminal of the pulse sequence unit 104. The third terminal of the phase selector 1054 is connected to the first terminal of the phase shifter 1053. The fourth and fifth terminals of the phase selector 1054 are connected to the seventh and eighth terminals of the low noise receiving unit 106, respectively.

[0123] Each second terminal of the phase shifter 1053 is connected to each first terminal of the high-voltage power amplifier array 1051, the first terminal of the first digital-to-analog converter 1052 is connected to the third terminal of the pulse sequence unit 104, and each second terminal of the first digital-to-analog converter 1052 is connected to each second terminal of the high-voltage power amplifier array 1051.

[0124] The third and fourth terminals of the high-voltage power amplifier array 1051 are respectively connected to the third and fourth terminals of the low-noise receiving unit 106.

[0125] The phase selector 1054 is used to determine the target radio frequency signal from each radio frequency signal and output it to the phase shifter 1053, and to output a corresponding reference signal to the low noise receiving unit 106 according to the target radio frequency signal.

[0126] The phase selector 1054 is also used to achieve phase modulation under the action of the first pulse signal.

[0127] The first digital-to-analog converter 1052 is used to achieve amplitude modulation under the action of the second pulse signal and output analog voltage to the high-voltage power amplifier array 1051.

[0128] The high-voltage power amplifier array 1051 is used to adjust the radio frequency pulse output to the radio frequency coil 101 under the action of the target radio frequency signal and the analog voltage.

[0129] Optionally, the target radio frequency signal can be any phase of a radio frequency signal with different phases, or it can be a radio frequency signal whose phase is synchronized with the pulse signal input to the gradient control unit 107, or it can be a radio frequency signal whose phase is relatively close to the phase of the pulse signal input to the gradient control unit 107. This application embodiment does not limit this.

[0130] Optionally, the phase shifter 1053 can adjust the phase of the target radio frequency signal. The phase shifter 1053 can advance or lag the phase of the target radio frequency signal, and can also output two adjusted target radio frequency signals to the high-voltage power amplifier array 1051 respectively. This ensures that the target radio frequency signal can be synchronized with the pulse signal input to the gradient control unit 107, that is, to achieve synchronization between each gradient magnetic field signal and the radio frequency pulse, so as to accurately and reliably spatially encode the atomic nuclei of the object to be sampled, thereby ensuring the accuracy and reliability of magnetic resonance imaging.

[0131] The target radio frequency signal and the analog voltage can adjust the output power of the high-voltage power amplifier array 1051, thereby adjusting the radio frequency pulse output to the radio frequency coil 101.

[0132] It is worth noting that by implementing phase modulation and amplitude modulation, different magnetic resonance imaging sequences can be achieved. This ensures that the magnetic resonance imaging scanner can accurately select layers and spatially locate the object being sampled during scanning, and accurately determine the layer selection and spatial location of each sampling signal corresponding to the object being sampled. This ensures the effectiveness of the magnetic resonance imaging.

[0133] In one possible implementation, see [link to relevant documentation]. Figure 4 The high-voltage power amplifier array 1051 includes multiple high-voltage power amplifiers U0.

[0134] Each high-voltage power amplifier U0 includes a first switch Q1, a second switch Q2, a third switch Q3, a fourth switch Q4, a first capacitor C1, a second capacitor C2, a first inductor L1, and a second inductor L2.

[0135] Optionally, the high-voltage power amplifiers U0 are connected in parallel, and all high-voltage power amplifiers U0 have the same parameters. The number of high-voltage power amplifiers U0 can be set by relevant technical personnel according to actual needs, and generally the number of high-voltage power amplifiers U0 can be set to 63.

[0136] Optionally, the high-voltage power amplifier array 1051 also includes multiple control switches K0.

[0137] Each control switch K0 is connected between each high-voltage power amplifier U0 and each first digital-to-analog converter 1052.

[0138] In addition, each control switch K0 can be connected to the pulse sequence unit 104, which outputs a corresponding pulse signal to the control terminal of each control switch K0 to control the conduction or cutoff of each control switch K0, thereby adjusting the number of enabled high-voltage power amplifiers U0.

[0139] It is worth noting that the driving capability of the high-voltage power amplifier array 1051 changes accordingly when the number of enabled high-voltage power amplifiers U0 changes. Generally, the more enabled high-voltage power amplifiers U0, the stronger the driving capability of the high-voltage power amplifier array 1051, that is, the higher the voltage of the RF pulse output by the high-voltage power amplifier array 1051. In other words, the more control switches K0 controlled to be closed by the pulse sequence unit 104, the stronger the driving capability of the high-voltage power amplifier array 1051.

[0140] In this way, the radio frequency pulses output to the radio frequency coil 101 can be accurately adjusted as needed, thereby improving the effect of magnetic resonance imaging.

[0141] It should be noted that, Figure 4 The output terminals of each high-voltage power amplifier U0 shown are merely illustrative and do not imply that each high-voltage power amplifier U0 can only have one output terminal. Each high-voltage power amplifier U0 may include two output terminals, which can be connected together as the fourth and fifth terminals of the transmitting unit 105 to output radio frequency pulses to drive the radio frequency coil 101. The connection method for connecting the two output terminals of each high-voltage power amplifier U0 together can be found in [reference needed]. Figure 4 The connection method is shown in the figure.

[0142] In addition, the specific connection relationships between each high-voltage power amplifier U0 and the first digital-to-analog converter 1052, phase shifter 1053, and each control switch K0 can be found in [reference needed]. Figure 4 The embodiments of this application will not be described in detail here.

[0143] In one possible implementation, see [link to relevant documentation]. Figure 5 The first terminal of the first inductor L1 and the second terminal of the second inductor L2 are used to input the working voltage, respectively.

[0144] The second end of the first inductor L1 is connected to the first plate of the first capacitor C1 and the drain of the first switching transistor Q1, respectively. The second plate of the first capacitor C1 is connected to the first end of the RF coil 101, and the source of the first switching transistor Q1 is connected to the drain of the second switching transistor Q2.

[0145] The second end of the second inductor L2 is connected to the first plate of the second capacitor C2 and the drain of the third switch Q3, respectively. The second plate of the second capacitor C2 is connected to the second end of the RF coil 101, and the source of the third switch Q3 is connected to the drain of the fourth switch Q4.

[0146] The gates of the first switch Q1 and the third switch Q3 are respectively connected to the second terminal of the first digital-to-analog converter 1052, and the gates of the second switch Q2 and the fourth switch Q4 are respectively connected to the second terminal of the phase shifter 1053.

[0147] The source of the third switch Q3 and the source of the fourth switch Q4 are grounded.

[0148] Optionally, the first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4 can all be N-channel switches, such as NMOS transistors.

[0149] Optionally, the gates of the first switch Q1 and the third switch Q3 are used to input the analog voltage, and the gates of the second switch Q2 and the fourth switch Q4 are used to input the target radio frequency signal adjusted by the phase shifter 1053.

[0150] For example, the gate of the second switch Q2 can be used to input the target RF signal whose phase is advanced by the phase shifter 1053, and the gate of the fourth switch Q4 can be used to input the target RF signal whose phase is delayed by the phase shifter 1053.

[0151] In addition, the first switch Q1 and the third switch Q3 can be high-voltage hybrid transistors, which can increase the operating voltage input to the first terminal of the first inductor L1 and the second terminal of the second inductor L2, thereby increasing the voltage at the drain of the first switch Q1 and the drain of the third switch Q3.

[0152] This can increase the voltage of the radio frequency pulse output to the radio frequency coil 101 by the high voltage transmitting unit 105 or the high voltage power amplifier array 1051, thereby improving the driving capability of the high voltage transmitting unit 105 or the high voltage power amplifier array 1051.

[0153] In one possible implementation, see [link to relevant documentation]. Figure 6 The low-noise receiving unit 106 includes a low-noise amplifier 1061, a first filter subunit 1062, and a second filter subunit 1063.

[0154] The first and second terminals of the low-noise amplifier 1061 are connected to the fourth and fifth terminals of the high-voltage transmitting unit 105, respectively, and the third terminal of the low-noise amplifier 1061 is connected to the first terminal of the first filter subunit 1062 and the first terminal of the second filter subunit 1063, respectively.

[0155] The fourth terminal of the low-noise amplifier 1061 is connected to the second terminal of the first filter subunit 1062 and the second terminal of the second filter subunit 1063, respectively.

[0156] The third terminal of the first filter subunit 1062 is connected to the fourth terminal of the phase selector 1054, and the third terminal of the second filter subunit 1063 is connected to the fifth terminal of the phase selector 1054.

[0157] The fourth terminal of the first filter subunit 1062 is connected to the second terminal of the microcontroller unit, and the fourth terminal of the second filter subunit 1063 is connected to the third terminal of the microcontroller unit.

[0158] It is worth noting that the low-noise amplifier 1061 can refer to an amplifier with a very low noise figure. The low-noise amplifier 1061 can initially amplify the sampled signal and reduce noise interference in the sampled signal to avoid the influence of noise interference in the sampled signal on magnetic resonance imaging.

[0159] The first filtering subunit 1062 and the second filtering subunit 1063 can further amplify and filter the sampled signal after the initial amplification by the low-noise amplifier 1061, so as to further reduce the noise present in the signal output to the microcontroller unit.

[0160] One possible approach, see [link / reference] Figure 6 The first filtering subunit 1062 includes a first mixer H1, a first operational amplifier U1, and a first low-pass filter T1.

[0161] The first and second terminals of the first mixer H1 are connected to the third and fourth terminals of the low-noise amplifier 1061, respectively. The third terminal of the first mixer H1 is connected to the fourth terminal of the phase selector 1054. The fourth and fifth terminals of the first mixer H1 are connected to the first and second terminals of the first operational amplifier U1, respectively.

[0162] The third terminal of the first operational amplifier U1 is connected to the first terminal of the first low-pass filter T1, and the second terminal of the first low-pass filter T1 is connected to the second terminal of the microcontroller unit.

[0163] The second filter subunit 1063 includes a second mixer H2, a second operational amplifier U2, and a second low-pass filter T2.

[0164] The first and second terminals of the second mixer H2 are connected to the third and fourth terminals of the low-noise amplifier 1061, respectively. The third terminal of the second mixer H2 is connected to the fifth terminal of the phase selector 1054. The fourth and fifth terminals of the second mixer H2 are connected to the first and second terminals of the second operational amplifier U2, respectively.

[0165] The third terminal of the second operational amplifier U2 is connected to the first terminal of the second low-pass filter T2, and the second terminal of the second low-pass filter T2 is connected to the third terminal of the microcontroller unit.

[0166] Optionally, the fourth and fifth terminals of the phase selector 1054 can also be used to output quadrature local oscillator (LO) drive signals to drive the first mixer H1 and the second mixer H2 to work.

[0167] Alternatively, a mixer is a device whose output signal frequency is equal to the sum, difference, quotient, or product of the frequencies of two input signals.

[0168] The input signals to the first mixer H1 can be the LO drive signal output from the fourth terminal of the phase selector 1054 and the sampled voltage after preliminary amplification by the low-noise amplifier 1061. The input signals to the second mixer H2 can be the LO drive signal output from the fifth terminal of the phase selector 1054 and the sampled voltage after preliminary amplification by the low-noise amplifier 1061. This allows adjustment of the frequencies of the signals output from the first mixer H1 and the second mixer H2.

[0169] Optionally, the first low-pass filter T1 and the second low-pass filter T2 refer to electronic filtering devices that allow certain frequencies to pass through while blocking other frequencies.

[0170] This reduces noise in the signal output to the microcontroller unit, thus avoiding the impact of noise in the sampled signal on magnetic resonance imaging and improving the imaging effect.

[0171] In one possible implementation, see [link to relevant documentation]. Figure 7 The pulse sequence unit 104 includes a memory S, a pulse programmer B, and a coordinator X.

[0172] The first end of the memory S is connected to the first end of the microcontroller unit, the second and third ends of the memory S are connected to the first and second ends of the pulse programmer B, respectively, and the third end of the memory S is connected to the first end of the coordinator X.

[0173] The second terminal of the pulse programmer B is connected to the second terminal of the coordinator X. The third terminal of the coordinator X is connected to the first terminal of the gradient control unit 107. The fourth and fifth terminals of the coordinator X are connected to the first and second terminals of the high-voltage transmitting unit 105, respectively. The sixth and seventh terminals of the coordinator X are connected to the first and second terminals of the low-noise receiving unit 106, respectively. The eighth terminal of the coordinator X is used to input an enable signal.

[0174] The memory S is used to receive and store the pulse commands output by the microcontroller unit.

[0175] Pulse programmer B is used to generate corresponding pulse signals according to the pulse instruction, and coordinator X is used to forward each pulse signal to the corresponding port.

[0176] For example, the coordinator X can forward a first pulse signal to a phase selector 1054, a second pulse signal to a first digital-to-analog converter 1052, a third pulse signal to a gradient control unit 107, and a fourth pulse signal to a low-noise receiving unit 106 and / or a switching unit 108.

[0177] The coordinator X can also forward the corresponding pulse signals to each control switch K0 to control the on and off of each control switch K0.

[0178] Optionally, the memory S can be a 64×128-bit memory array. The memory S can also store any other possible information, which is not limited in this embodiment.

[0179] This can improve the timing accuracy of the pulse sequence unit 104 in controlling other units or devices, and reduce the control complexity of the pulse sequence unit 104.

[0180] In one possible implementation, the gradient control unit 107 includes a plurality of second digital-to-analog converters.

[0181] Each of the second digital-to-analog converters includes a two-stage operational amplifier with a ladder network.

[0182] Each second digital-to-analog converter is used to output a corresponding control signal to the gradient coil unit 102 under the action of the third pulse signal, so that the gradient coil unit 102 outputs each gradient magnetic field signal according to a preset time interval and a preset amplitude.

[0183] Optionally, each second digital-to-analog converter can be an 8-bit DAC. Specifically, the two-stage operational amplifier with a ladder network can be a two-stage operational amplifier with an R-2R ladder network.

[0184] The number of each second digital-to-analog converter can be 3, and each second digital-to-analog converter corresponds to the first direction, the second direction, and the third direction mentioned above, respectively.

[0185] The pulse programmer B can control the corresponding second digital-to-analog converter according to the control word of the gradient control unit 107 indicated in the pulse instruction, and keep the output pulse synchronized with the corresponding radio frequency pulse according to the amplitude and specific phase of each pulse signal indicated in the pulse instruction and the time of the output pulse.

[0186] In other words, each of the second digital-to-analog converters can control the gradient coil unit 102 to output gradient magnetic field signals in different directions under the action of the pulse signal, such as the first gradient magnetic field signal, the second gradient magnetic field signal, and the third gradient magnetic field signal, so that the gradient magnetic field output by the gradient coil unit 102 in different directions is superimposed with the excitation magnetic field.

[0187] In one possible implementation, see [link to relevant documentation]. Figure 8 The magnetic resonance imaging scanner also includes a shimming coil unit 109.

[0188] The shimming coil unit 109 is used to output a uniform magnetic field to compensate for the gradient magnetic fields generated by the gradient coil unit 102.

[0189] Optionally, the shimming coil unit 109 includes a shimming coil 1091 and a shimming coil driver 1092.

[0190] The first terminal of the shimming coil driver 1092 is used for input voltage, and the second terminal of the shimming coil driver 1092 is connected to the shimming coil 1091.

[0191] The shim coil driver 1092 is used to output a corresponding operating voltage to the shim coil 1091 so that the shim coil 1091 generates a shim magnetic field to compensate for the above-mentioned gradient magnetic fields.

[0192] This ensures the uniformity of the magnetic field distribution and the stability of the magnetic field strength, thereby guaranteeing the effectiveness of magnetic resonance imaging.

[0193] Figure 9 This is a schematic diagram of the structure of a magnetic resonance imaging system provided in an embodiment of this application. See also... Figure 9 The magnetic resonance imaging system includes: a microcontroller unit 200, a radio frequency signal generation unit 300, and a magnetic resonance imaging scanner provided in any of the above embodiments.

[0194] The microcontroller unit 200 and the radio frequency signal generation unit 300 are respectively connected to the magnetic resonance imaging scanner.

[0195] The magnetic resonance imaging system described above is similar in principle and technical effect to the magnetic resonance imaging scanner provided in the aforementioned embodiments, and will not be described again here.

[0196] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0197] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A magnetic resonance imaging scanner, characterized by, It includes a radio frequency coil, a gradient coil unit, and an integrated circuit, wherein the integrated circuit includes a pulse sequence unit, a high-voltage transmitting unit, a low-noise receiving unit, a gradient control unit, and a switching unit; The first end of the pulse sequence unit is used to connect to the microcontroller unit. The second and third ends of the pulse sequence unit are connected to the first and second ends of the high-voltage transmitting unit, respectively. The fourth end of the pulse sequence unit is connected to the first end of the low-noise receiving unit and to the switching unit. The fifth end of the pulse sequence unit is connected to the second end of the low-noise receiving unit. The sixth end of the pulse sequence unit is connected to the first end of the gradient control unit. The third terminal of the high-voltage transmitting unit is used to input radio frequency signals of different phases. The fourth and fifth terminals of the high-voltage transmitting unit are respectively connected to the third and fourth terminals of the low-noise receiving unit through the switching unit. The fifth and sixth terminals of the low-noise receiving unit are respectively used to connect to the microcontroller unit. The second terminal of the gradient control unit is connected to the gradient coil unit. The first and second terminals of the radio frequency coil are respectively connected to the fourth and fifth terminals of the high-voltage transmitting unit. The pulse sequence unit is used to generate and output pulse signals; the high-voltage transmitting unit is used to adjust the radio frequency pulses output to the radio frequency coil under the action of the pulse signals and the radio frequency signals. The gradient control unit is used to control the gradient coil unit to output gradient magnetic field signals in different directions under the action of pulse signals; The low-noise receiving unit is used to receive and amplify the sampling signal output by the radio frequency coil under the action of the pulse signal, and output the amplified sampling signal to the microcontroller unit by down-frequency reduction.

2. The magnetic resonance imaging scanner of claim 1, wherein, The gradient coil unit includes a gradient coil driver and a gradient coil; The first end of the gradient coil driver is connected to the second end of the gradient control unit, and the second end of the gradient coil driver is connected to the gradient coil. The gradient coil driver is used to output a corresponding operating voltage to the gradient coil under the control of the gradient control unit, so that the gradient coil outputs each gradient magnetic field signal.

3. The magnetic resonance imaging scanner of claim 1, wherein, The high-voltage transmitting unit includes a high-voltage power amplifier array, a first digital-to-analog converter, a phase shifter, and a phase selector; The first terminal of the phase selector is used to input each of the radio frequency signals, the second terminal of the phase selector is connected to the second terminal of the pulse sequence unit, the third terminal of the phase selector is connected to the first terminal of the phase shifter, and the fourth and fifth terminals of the phase selector are respectively connected to the seventh and eighth terminals of the low noise receiving unit. Each second terminal of the phase shifter is connected to each first terminal of the high-voltage power amplifier array, each first terminal of the first digital-to-analog converter is connected to the third terminal of the pulse sequence unit, and each second terminal of the first digital-to-analog converter is connected to each second terminal of the high-voltage power amplifier array. The third and fourth terminals of the high-voltage power amplifier array are respectively connected to the third and fourth terminals of the low-noise receiving unit. The phase selector is used to determine the target radio frequency signal from each of the radio frequency signals and output it to the phase shifter, and to output a corresponding reference signal to the low noise receiving unit according to the target radio frequency signal. The phase selector is also used to realize phase modulation under the action of the first pulse signal. The first digital-to-analog converter is used to achieve amplitude modulation under the action of the second pulse signal and output analog voltage to the high-voltage power amplifier array; The high-voltage power amplifier array is used to adjust the radio frequency pulse output to the radio frequency coil under the action of the target radio frequency signal and the analog voltage.

4. The magnetic resonance imaging scanner of claim 3, wherein, The high-voltage power amplifier array includes multiple high-voltage power amplifiers, which are connected in parallel and have the same parameters. Each of the aforementioned high-voltage power amplifiers includes a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a first capacitor, a second capacitor, a first inductor, and a second inductor.

5. The magnetic resonance imaging scanner of claim 4, wherein, The first terminal of the first inductor and the first terminal of the second inductor are respectively used for input operating voltage; The second end of the first inductor is connected to the first plate of the first capacitor and the drain of the first switching transistor, respectively. The second plate of the first capacitor is connected to the first end of the radio frequency coil, and the source of the first switching transistor is connected to the drain of the second switching transistor. The second end of the second inductor is connected to the first plate of the second capacitor and the drain of the third switching transistor, the second plate of the second capacitor is connected to the second end of the radio frequency coil, and the source of the third switching transistor is connected to the drain of the fourth switching transistor. The gates of the first and third switching transistors are respectively connected to the second terminal of the first digital-to-analog converter, and the gates of the second and fourth switching transistors are respectively connected to the second terminal of the phase shifter. The source of the second switch and the source of the fourth switch are grounded.

6. The magnetic resonance imaging scanner of claim 3, wherein, The low-noise receiving unit includes a low-noise amplifier, a first filtering subunit, and a second filtering subunit; The first and second terminals of the low-noise amplifier are respectively connected to the fourth and fifth terminals of the high-voltage transmitting unit, and the third terminal of the low-noise amplifier is respectively connected to the first terminal of the first filter subunit and the first terminal of the second filter subunit. The fourth terminal of the low-noise amplifier is connected to the second terminal of the first filter subunit and the second terminal of the second filter subunit, respectively. The third terminal of the first filter subunit is connected to the fourth terminal of the phase selector, and the third terminal of the second filter subunit is connected to the fifth terminal of the phase selector. The fourth terminal of the first filtering subunit is connected to the second terminal of the microcontroller unit, and the fourth terminal of the second filtering subunit is connected to the third terminal of the microcontroller unit.

7. The magnetic resonance imaging scanner of claim 6, wherein, The first filtering subunit includes a first mixer, a first operational amplifier, and a first low-pass filter; The first and second terminals of the first mixer are connected to the third and fourth terminals of the low-noise amplifier, respectively. The third terminal of the first mixer is connected to the fourth terminal of the phase selector. The fourth and fifth terminals of the first mixer are connected to the first and second terminals of the first operational amplifier, respectively. The third terminal of the first operational amplifier is connected to the first terminal of the first low-pass filter, and the second terminal of the first low-pass filter is connected to the second terminal of the microcontroller unit. The second filtering subunit includes a second mixer, a second operational amplifier, and a second low-pass filter; The first and second terminals of the second mixer are connected to the third and fourth terminals of the low-noise amplifier, respectively. The third terminal of the second mixer is connected to the fifth terminal of the phase selector. The fourth and fifth terminals of the second mixer are connected to the first and second terminals of the second operational amplifier, respectively. The third terminal of the second operational amplifier is connected to the first terminal of the second low-pass filter, and the second terminal of the second low-pass filter is connected to the third terminal of the microcontroller unit.

8. The magnetic resonance imaging scanner of claim 1, wherein, The pulse sequence unit includes a memory, a pulse programmer, and a coordinator; The first end of the memory is connected to the first end of the microcontroller, the second and third ends of the memory are connected to the first and second ends of the pulse programmer, respectively, and the third end of the memory is connected to the first end of the coordinator. The second terminal of the pulse programmer is connected to the second terminal of the coordinator, the third terminal of the coordinator is connected to the first terminal of the gradient control unit, the fourth and fifth terminals of the coordinator are connected to the first and second terminals of the high-voltage transmitting unit, respectively, the sixth and seventh terminals of the coordinator are connected to the first and second terminals of the low-noise receiving unit, respectively, and the eighth terminal of the coordinator is used to input an enable signal. The memory is used to receive and store the pulse commands output by the microcontroller unit; The pulse programmer is used to generate corresponding pulse signals according to the pulse instructions, and the coordinator is used to forward each pulse signal to the corresponding port.

9. The magnetic resonance imaging scanner of claim 1, wherein, The gradient control unit includes multiple second digital-to-analog converters; Each of the second digital-to-analog converters includes a two-stage operational amplifier with a ladder network; Each of the second digital-to-analog converters is used to output a corresponding control signal to the gradient coil unit under the action of the third pulse signal, so that the gradient coil unit outputs the gradient magnetic field signal according to a preset time interval and a preset amplitude.

10. A magnetic resonance imaging system, characterized by Includes a microcontroller unit, a radio frequency signal generation unit, and a magnetic resonance imaging scanner as described in any one of claims 1-9; The microcontroller unit and the radio frequency signal generation unit are respectively connected to the magnetic resonance imaging scanner.

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