阅读说明：本技术 一种可变场核磁共振系统及核磁共振信号测量方法 (Variable field nuclear magnetic resonance system and nuclear magnetic resonance signal measuring method ) 是由 刘文中 郭斯琳 胡朋 程晶晶 于 2019-10-29 设计创作，主要内容包括：本发明公开了一种可变场核磁共振系统及核磁共振信号测量方法,系统包括：静磁场发生装置,用于通过可调恒流源,驱动激励磁场输出线圈产生直流静磁场；高频磁场发生装置,用于通过函数信号发生器驱动高频磁场输出线圈,对施加有静磁场的被检体照射高频磁场；基于隧道磁阻传感器的信号检测装置,用于采用隧道磁阻传感器作为探头,接收被检体产生的核磁共振信号。本发明的静磁场发生装置基于精密可调恒流源驱动激励磁场线圈产生稳定可控的直流磁场,使得主磁场根据实际需要可调。另外,基于TMR传感器制成的探头接收待测体产生的核磁共振信号,使得探测信号信噪比高,因此,本发明核磁共振装置能够有效满足实际科研或生产过程中的高效测试需求。(The invention discloses a variable field nuclear magnetic resonance system and a nuclear magnetic resonance signal measuring method, wherein the system comprises: the static magnetic field generating device is used for driving the excitation magnetic field output coil to generate a direct-current static magnetic field through the adjustable constant current source; a high-frequency magnetic field generator for driving the high-frequency magnetic field output coil by the function signal generator and irradiating the subject to which the static magnetic field is applied with a high-frequency magnetic field; the signal detection device based on the tunnel magnetoresistive sensor is used for receiving a nuclear magnetic resonance signal generated by a detected body by adopting the tunnel magnetoresistive sensor as a probe. The static magnetic field generating device drives the exciting magnetic field coil to generate a stable and controllable direct-current magnetic field based on the precise adjustable constant-current source, so that the main magnetic field can be adjusted according to actual requirements. In addition, the probe made based on the TMR sensor receives the nuclear magnetic resonance signal generated by the body to be tested, so that the signal-to-noise ratio of the detection signal is high, and therefore, the nuclear magnetic resonance device can effectively meet the high-efficiency test requirement in the actual scientific research or production process.)

1. A variable field nuclear magnetic resonance system, comprising:

the static magnetic field generating device is driven by an adjustable constant current source and is used for driving an excitation magnetic field output coil to generate a direct-current static magnetic field through the adjustable constant current source;

a high-frequency magnetic field generator for driving a high-frequency magnetic field output coil by a function signal generator and irradiating a high-frequency magnetic field to a subject to which the static magnetic field is applied;

and the signal detection device based on the tunnel magnetoresistive sensor is used for receiving the nuclear magnetic resonance signal generated by the detected body by adopting the tunnel magnetoresistive sensor as a probe.

2. The variable field nmr system of claim 1, wherein the signal detection device is further configured to: and amplifying and filtering the nuclear magnetic resonance signal received by the tunnel magnetoresistive sensor to obtain preprocessing information.

3. The system of claim 2, wherein the signal detection device comprises an instrumentation amplifier, two tunnel magnetoresistive sensors respectively connected to an input of the instrumentation amplifier, and a filter connected to an output of the instrumentation amplifier, wherein the two tunnel magnetoresistive sensors form a differential structure to eliminate a background magnetic field when acquiring the nmr signal.

4. The variable field nuclear magnetic resonance system of claim 2, further comprising: and the information processing device is used for acquiring the preprocessing information by adopting a data card, performing analog-to-digital conversion on the preprocessing information and inputting the preprocessed information into the data processing terminal.

5. The variable field nuclear magnetic resonance system of any one of claims 1 to 4 wherein the static magnetic field generating means is specifically configured to:

and according to the actual magnetic field requirement, changing the driving current of the adjustable constant current source and driving the exciting magnetic field coil to generate a direct-current static magnetic field with a preset size.

6. The variable field nuclear magnetic resonance system according to claim 5, wherein said static magnetic field generating means comprises an adjustable reference voltage, a low load factor sampling resistor, an operational amplifier and an adjusting tube, wherein said adjustable reference voltage is connected to a forward input terminal of said operational amplifier, a voltage high terminal of said sampling resistor is connected to a reverse input terminal of said operational amplifier, two segments of said adjusting tube are respectively connected to an output terminal of said operational amplifier and said voltage high terminal, and a voltage low terminal of said sampling resistor is externally connected to said excitation magnetic field coil.

7. A method of nuclear magnetic resonance signal measurement, comprising:

s1, obtaining nuclear magnetic resonance signals of the examined body under a specific direct current static magnetic field by using the variable field nuclear magnetic resonance system according to any one of claims 1 to 6;

and S2, if the nuclear magnetic resonance signals under other static magnetic fields are measured, adjusting a static magnetic field generating device in the variable-field nuclear magnetic resonance system to generate the other static magnetic fields, and repeatedly executing S1.