A nuclear magnetic resonance angular velocity sensor system and a relaxation error suppression method

Abstract

The application provides a nuclear magnetic resonance angular velocity sensor system and a relaxation error suppression method, which comprises an atomic gas chamber, a lambda / 4 wave plate, a first laser, a second laser, a first collimating lens, a second collimating lens, a first linear polarizer, a second linear polarizer, a three-axis magnetic field coil, an oven, a photoelectric detector, a magnetic shielding barrel, a PBS and a balanced photoelectric detector; a static magnetic field, a modulation magnetic field and pumping light are longitudinally applied to the nuclear magnetic resonance angular velocity sensor system; detection light and nuclear resonance magnetic field are transversely applied to the nuclear magnetic resonance angular velocity sensor system, so that the nuclear magnetic resonance angular velocity sensor is in a working state; the influence of unstable electron spin relaxation time on nuclear precession frequency measurement is considered, nuclear precession frequency measurement error is suppressed, and the measurement performance of angular velocity is improved.

Description

Technical Field

[0001] This invention belongs to the field of atomic sensor technology, and in particular to a nuclear magnetic resonance angular velocity sensor system and a relaxation error suppression method. By appropriately matching the reference frequency with the nucleon precession frequency, the measurement error of the nucleon precession frequency caused by the instability of the electron spin relaxation time is compensated, thereby improving the performance of the nuclear magnetic resonance angular velocity sensor. Background Technology

[0002] In recent years, with the rapid development of atomic physics, atomic sensors have gradually received attention and importance; nuclear magnetic resonance angular velocity sensors, with their advantages of high precision and small size, are the future development direction of inertial navigation.

[0003] The angular velocity of the sensor is obtained by extracting the precession frequencies of 129Xe and 131Xe nucleons. The nucleon precession signal is obtained through an embedded electron paramagnetic resonance magnetometer. The performance of the embedded magnetometer directly affects the measurement of the nucleon precession frequency. The electron spin relaxation time, as one of the key indicators of the magnetometer system, is unstable and will directly cause the measurement error of the nuclear magnetic resonance angular velocity sensor. Therefore, it is necessary to conduct applied research on electron spin relaxation error suppression methods. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a nuclear magnetic resonance angular velocity sensor system and a relaxation error suppression method. This system overcomes the influence of electron spin relaxation time instability on nucleon precession frequency measurement. By appropriately matching the reference frequency with the nucleon precession frequency, the measurement error of nucleon precession frequency caused by electron spin relaxation time instability is compensated, thereby greatly improving the angular velocity measurement performance.

[0005] A nuclear magnetic resonance angular velocity sensor system and a relaxation error suppression method, wherein:

[0006] A nuclear magnetic resonance angular velocity sensor system, comprising:

[0007] Atomic gas cell, λ / 4 waveplate, first laser, second laser, first collimating lens, second collimating lens, first linear polarizer, second linear polarizer, triaxial magnetic field coil, oven, photodetector, magnetic shielding barrel, PBS, balanced photodetector;

[0008] in:

[0009] The atomic gas chamber serves as the core sensing element of the nuclear magnetic resonance angular velocity sensor.

[0010] The λ / 4 waveplate is used to provide circularly polarized pump light.

[0011] The first laser: used to provide pump light for the nuclear magnetic resonance angular velocity sensor;

[0012] The second laser serves as a detection light source, providing detection light.

[0013] The first collimating lens is used to collimate the pump light.

[0014] The second collimating lens is used to collimate the detection light.

[0015] The first and second linear polarizers are used to provide linearly polarized light with stable polarization states.

[0016] The triaxial magnetic field coil is used to generate a working magnetic field.

[0017] The oven is used for heat insulation of the atomic gas chamber.

[0018] The photodetector is used for post-bubble detection in the pump optical path.

[0019] The magnetic shielding barrel is used to shield the ambient magnetic field.

[0020] The PBS and the balanced photodetector together constitute a balanced differential detection module, which is used to detect magnetic field signals.

[0021] As an example, the working magnetic field includes: a static magnetic field, a modulation magnetic field, a nuclear resonance magnetic field, and a reference magnetic field.

[0022] A relaxation error suppression method based on a nuclear magnetic resonance angular velocity sensor system includes:

[0023] Step 1: By applying a static magnetic field, a modulation magnetic field, and pump light longitudinally to the nuclear magnetic resonance angular velocity sensor system, and applying a detection light and a nuclear resonance magnetic field laterally, the nuclear magnetic resonance angular velocity sensor is put into operation.

[0024] Step 2: Obtain the nucleon precession signal, lock the nucleon precession phase using a phase-locked loop, and obtain the nucleon precession frequency;

[0025] As an example, the nucleon includes: 129 Xe and 131 Xe.

[0026] As an example, since the nuclear magnetic resonance angular velocity sensor uses the nucleon precession signal to sense the angular velocity, the Bloch equation formula for the nucleon precession signal is designed as follows:

[0027]

[0028] Where: K + K is the transverse magnetic moment of the nucleon. zWhere γ is the longitudinal magnetic moment of the nucleon, and γ is the gyromagnetic ratio of the nucleon. The nuclear resonance magnetic field applied laterally, T2 is the transverse spin relaxation time of the nucleon, and B is the longitudinal static magnetic field.

[0029] Solving equation (1) yields the nucleus precession signal expressions for the x and y axes, as shown in equation (2):

[0030]

[0031] Where: K x K is the magnetic moment along the x-axis of the nucleon. y For the nucleon's y-axis magnetic moment, K z Where γ is the longitudinal magnetic moment of the nucleon, γ is the nucleon gyromagnetic ratio, and B is the longitudinal static magnetic field. i ω is the amplitude of the transversely applied nucleon resonant magnetic field, T2 is the transverse spin relaxation time of the nucleon, and ω i It is the frequency of the nuclear resonance magnetic field.

[0032] As an example, the formula for determining the precession frequency of the nucleus is designed as follows:

[0033]

[0034] Where: B is the longitudinal static magnetic field, ω r β represents the effect of angular velocity and nucleon signal phase delay.

[0035] As an example, it can be seen from the above formula (3) that the instability of the longitudinal static magnetic field will affect the precession frequency of the nucleons. Therefore, it is necessary to adjust the angular velocity ω caused by the longitudinal static magnetic field. r Measurement errors are suppressed; a dual-core-based approach is adopted. 129 Xe and 131 The Xe differential angular velocity measurement method, combined with the nucleon gyromagnetic ratio characteristics, is used to suppress the nucleon precession frequency error. The design formula (4) is shown below:

[0036]

[0037] Where: ω r 'The measured angular velocity; this dual-nuclear differential method can eliminate the error caused by the unstable longitudinal static magnetic field B, and improve the accuracy of angular velocity measurement.'

[0038] As an example, since the error of the nucleon signal phase delay β and the transverse spin relaxation time of the nucleon are difficult to achieve in accordance with the nucleon gyromagnetic ratio, the above error is difficult to eliminate by the dual nucleon differential method. Therefore, it is necessary to suppress the error of the nucleon signal phase delay β.

[0039] As an example, the nuclear magnetic resonance angular velocity sensor uses an embedded electron paramagnetic resonance magnetometer to measure the nucleon precession frequency. According to the electron spin Bloch equation, the electron magnetic moment signal can be obtained, as shown in formula (5). This takes into account the laterally applied reference magnetic field. The signal form at that time is used for the analysis of nuclear precession signals.

[0040]

[0041] Where: M x The signal is the electron magnetic moment, τ is the current electron spin relaxation time, and M is the electron magnetic moment signal. z For the z-axis electron magnetic moment, γ Rb For Rb, J i Let γ be the Bessel function, and let γ be the coefficient. Rb B c / ω c B c To modulate the magnetic field amplitude, ω c This is the current frequency of the modulated magnetic field.

[0042] Step 3: Measure the transverse spin relaxation time of the nucleon using the FID method. Combined with the nucleon gyromagnetic ratio and precession frequency, calculate the optimized reference signal frequency ω using the reference frequency selection formula. ref ';

[0043] The formula for selecting the reference frequency is designed as follows:

[0044]

[0045] in, and Nuclei 129 Xe and nuclei 131 The transverse spin relaxation time of Xe, γ 129 and γ 131 Nuclei 129 Xe and nuclei 131 The gyromagnetic ratio of Xe, ω 129 and ω 131 Nuclei 129 Xe and nuclei 131 The precession frequency of Xe, γ Rb B is the resonant frequency of Rb, ω c0 ω is the initial frequency of the modulation magnetic field. c The current modulation magnetic field frequency is τ0, the initial electron spin relaxation time is τ, and the current electron spin relaxation time is τ.

[0046] Step 4: Apply a transverse reference magnetic field to stabilize the phase of the reference signal, perform precise measurement of the nucleon precession frequency, and finally obtain the angular velocity signal.

[0047] The beneficial effects of this invention are:

[0048] Considering the impact of electron spin relaxation time instability on nucleon precession frequency measurement, a method for suppressing electron spin relaxation error based on reference frequency correction is proposed to suppress nucleon precession frequency measurement error and improve angular velocity measurement performance.

[0049] This method is scientifically sound and reliable. By appropriately matching the reference frequency with the nucleon precession frequency, it compensates for the measurement error of the nucleon precession frequency caused by the instability of the electron spin relaxation time, greatly improving the measurement performance of angular velocity and making it suitable for widespread application. Attached Figure Description

[0050] Figure 1 This is a flowchart illustrating the overall process design of a relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to the present invention.

[0051] Figure 2 This is a schematic diagram of a nuclear magnetic resonance angular velocity sensor system according to the present invention. (It includes direction indicators for the x, y, and z axes.)

[0052] Figure 3 This is a schematic diagram illustrating the principle of the FID method for measuring the transverse spin relaxation time of nucleons in a nuclear magnetic resonance angular velocity sensor system according to the present invention, which aims to suppress relaxation errors.

[0053] Figure 4 This is a demodulation result data diagram of an electron paramagnetic resonance magnetometer embedded in the relaxation error suppression method of a nuclear magnetic resonance angular velocity sensor system of the present invention; containing nuclei. 129 Xe precession signal and 131 The Xe precession signal is used to measure the precession frequency of nuclei and to select a reference frequency.

[0054] Figure 5 This is a schematic diagram showing the angular velocity measurement corresponding to the temperature fluctuation of the atomic gas chamber after selecting a reference frequency in the relaxation error suppression method of the nuclear magnetic resonance angular velocity sensor system of the present invention. Detailed Implementation

[0055] Below, for reference Figures 1 to 5 As shown, a nuclear magnetic resonance angular velocity sensor system and a relaxation error suppression method are described, wherein:

[0056] Reference Figure 2 As shown, a nuclear magnetic resonance angular velocity sensor system includes:

[0057] Atomic gas chamber 101, λ / 4 waveplate 102, first laser 103, second laser 104, first collimating lens 105, second collimating lens 106, first linear polarizer 107, second linear polarizer 108, triaxial magnetic field coil 109, oven 110, photodetector 111, magnetic shielding barrel 112, PBS 113, balanced photodetector 114;

[0058] in:

[0059] The atomic gas chamber 101 serves as the atomic gas chamber of the nuclear magnetic resonance angular velocity sensor and is the core sensitive element of the nuclear magnetic resonance angular velocity sensor.

[0060] The λ / 4 waveplate 102 is used to provide circularly polarized pump light;

[0061] The first laser 103 is used to provide pump light for the nuclear magnetic resonance angular velocity sensor;

[0062] The second laser 104: provides detection light as a detection light source;

[0063] The first collimating lens 105 is used to collimate the pump light;

[0064] The second collimating lens 106 is used to collimate the detection light;

[0065] The first linear polarizer 107 and the second linear polarizer 108 are used to provide linearly polarized light with stable polarization.

[0066] The triaxial magnetic field coil 109 is used to generate a working magnetic field;

[0067] The oven 110 is used for heat insulation of the atomic gas chamber 101.

[0068] The photodetector 111 is used for post-pumping detection of the optical path;

[0069] The magnetic shielding barrel 112 is used to shield the ambient magnetic field.

[0070] The PBS113 and the balanced photodetector 114 together constitute a balanced differential detection module, which is used to detect magnetic field signals.

[0071] By applying a static magnetic field, a modulated magnetic field, and pump light longitudinally, and applying detection light and a nuclear resonance magnetic field laterally, the nuclear magnetic resonance angular velocity sensor is put into operation.

[0072] As an example, the working magnetic field includes: a static magnetic field, a modulation magnetic field, a nuclear resonance magnetic field, and a reference magnetic field.

[0073] Reference Figure 1As shown, a relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system includes:

[0074] Step 1: By applying a static magnetic field, a modulation magnetic field, and pump light longitudinally to the nuclear magnetic resonance angular velocity sensor system, and applying a detection light and a nuclear resonance magnetic field laterally, the nuclear magnetic resonance angular velocity sensor is put into operation.

[0075] Step 2: Obtain the nucleon precession signal, lock the nucleon precession phase using a phase-locked loop, and obtain the nucleon precession frequency;

[0076] As an example, the nucleon includes: 129 Xe and 131 Xe.

[0077] As an example, since the nuclear magnetic resonance angular velocity sensor uses the nucleon precession signal to sense the angular velocity, the Bloch equation formula for the nucleon precession signal is designed as follows:

[0078]

[0079] Where: K + K is the transverse magnetic moment of the nucleon. z B is the longitudinal magnetic moment of the nucleon, γ is the gyromagnetic ratio of the nucleon, and B is the longitudinal magnetic moment of the nucleon. + For the transversely applied nucleon resonance magnetic field, B + =B i cosω i t and T2 are the transverse spin relaxation time of the nucleon, and B is the longitudinal static magnetic field.

[0080] Solving equation (1) yields the nucleus precession signal expressions for the x and y axes, as shown in equation (2):

[0081]

[0082] Where: K x K is the magnetic moment along the x-axis of the nucleon. y For the nucleon's y-axis magnetic moment, K z B is the longitudinal magnetic moment of the nucleon, γ is the gyromagnetic ratio of the nucleon, and B is the longitudinal magnetic moment of the nucleon. i ω represents the amplitude of the transversely applied nucleon resonance magnetic field. i T1 is the frequency of the nucleon resonant magnetic field, T2 is the transverse spin relaxation time of the nucleon, and B is the longitudinal static magnetic field.

[0083] As an example, the formula for determining the precession frequency of the nucleus is designed as follows:

[0084]

[0085] Where: B is the longitudinal static magnetic field, ω rβ represents the effect of angular velocity and nucleon signal phase delay.

[0086] As an example, it can be seen from the above formula (3) that the instability of the longitudinal static magnetic field will affect the precession frequency of the nucleons. Therefore, it is necessary to adjust the angular velocity ω caused by the longitudinal static magnetic field. r Measurement errors are suppressed; a dual-core-based approach is adopted. 129 Xe and 131 The Xe differential angular velocity measurement method, combined with the nucleon gyromagnetic ratio characteristics, is used to suppress the nucleon precession frequency error. The design formula (4) is shown below:

[0087]

[0088] This dual-core differential method can eliminate errors caused by the unstable static magnetic field B, thereby improving the accuracy of angular velocity measurement.

[0089] As an example, since the error of the nucleon signal phase delay β and the transverse spin relaxation time of the nucleon are difficult to achieve in accordance with the nucleon gyromagnetic ratio, the above error is difficult to eliminate by the dual nucleon differential method. Therefore, it is necessary to suppress the error of the nucleon signal phase delay β.

[0090] As an example, the nuclear magnetic resonance angular velocity sensor uses an embedded electron paramagnetic resonance magnetometer to measure the precession frequency of the nuclei. According to the Bloch equation, the electron magnetic moment signal can be obtained, as shown in formula (5).

[0091]

[0092] Among them, the electron magnetic moment signal is used to detect the precession signal of nucleons and to measure the precession frequency of nucleons.

[0093] Considering the application of a transverse reference magnetic field The signal form at that time is used for the analysis of nuclear precession signals.

[0094] As an example, to achieve nucleon resonance, a nucleon resonance magnetic field needs to be applied along the x-axis. In this case, the x-axis magnetic field signal contains two parts: the nucleon resonance magnetic field and the nucleon precession signal, while the y-axis magnetic field signal only contains the nucleon precession signal. The nucleon signal phase is measured by extracting the y-axis nucleon signal phase.

[0095] By demodulating formula (5) once, the y-axis magnetic field signal can be obtained, as shown in formula (6);

[0096]

[0097] Solving equation (6) yields the reference magnetic field. The phase information is used in a demodulation process to detect the nucleon precession phase and the reference signal phase.

[0098] As an example, the precession frequency of the nucleon is equal to the nucleon resonance frequency, and the phase delay of the nucleon signal satisfies... The phase of the measured signal is related to the frequency of the applied magnetic field signal, and the phase measurement values ​​corresponding to magnetic field signals of different frequencies are different; as shown in formula (7):

[0099]

[0100] Wherein: γ Rb B is the resonant frequency of Rb, ω c0 τ is the initial modulation magnetic field frequency, τ0 is the initial electron spin relaxation time, and ω is the initial frequency. 129 The resonant frequency is 129Xe. For a phase delay of 129Xe, ω 131 The resonant frequency is 131Xe. The phase delay is 131Xe. The aforementioned phase signals are the phase measurements of each parameter obtained after the first demodulation of the electron magnetic moment. The phase signals of 129Xe and 131Xe are used as the phase inputs of the phase-locked loop for nucleon precession frequency measurement, and the reference signal phase is used to suppress the phase error of the electron paramagnetic resonance magnetometer.

[0101] During the measurement, parameter instability typically occurs in the longitudinal static magnetic field B and the current electron spin relaxation time τ. Locking of the reference phase is achieved by adjusting ω. c Achieve this by adjusting ω when the longitudinal static magnetic field fluctuates. c This can suppress longitudinal static magnetic field errors and eliminate measurement signal phase errors caused by static magnetic field instability; however, when the electron spin relaxation time changes, ω will also be changed to achieve reference phase stability. c .

[0102] As an example, due to the inconsistency between the reference signal and the precession frequency of the nucleus, 129 Xe and 131 The phase measurement error of Xe still exists, and the detected nucleon precession phase signal is as shown in Equation (8):

[0103]

[0104] The aforementioned phase signals are the actual measured 129Xe and 131Xe phase values ​​when there is electron spin relaxation time instability; the precession frequency of the nucleus is obtained through a phase-locked loop scheme.

[0105] As an example, the phase error measured by the electron paramagnetic resonance magnetometer is considered to be the phase delay of the nucleon signal. The nucleon phase delay error when the electron spin relaxation time changes is shown in formula (9):

[0106] The phase of the measured reference signal satisfies:

[0107] arctan(γ Rb B+ω c +ω ref )τ=arctan(γ Rb B+ω c0 +ω ref )τ0;

[0108]

[0109] The above-mentioned nucleon phase delay error is substituted into formula (3) for the calculation of nucleon precession frequency error.

[0110] Nucleon phase delay error will cause nucleon precession frequency shift, which will ultimately lead to angular velocity measurement error, as shown in formula (10):

[0111]

[0112] The above formula is used to represent the angular velocity measurement error caused by the electron paramagnetic resonance magnetometer. By making the angular velocity measurement error zero, the error can be suppressed.

[0113] As an example, Formulas 5 to 10 are all used for the analysis of precession signals.

[0114] Step 3: Measure the transverse spin relaxation time of the nucleon using the FID method. Combined with the nucleon gyromagnetic ratio and precession frequency, calculate the optimized reference signal frequency ω using the reference frequency selection formula. ref ';reference Figure 3 As shown; the spin relaxation time of nucleons is obtained by fitting the envelope curve;

[0115] The formula for selecting the reference frequency is designed as formula (12):

[0116]

[0117] in, and Nuclei 129 Xe and nuclei 131 The transverse spin relaxation time of Xe, γ 129 and γ 131 Nuclei 129 Xe and nuclei 131 The gyromagnetic ratio of Xe, ω129 and ω 131 Nuclei 129 Xe and nuclei 131 The precession frequency of Xe, γ Rb B is the resonant frequency of Rb, ω c0 ω is the initial frequency of the modulation magnetic field. c The current modulation magnetic field frequency is τ0, the initial electron spin relaxation time is τ, and the current electron spin relaxation time is τ.

[0118] As an example, the angular velocity measurement error Δω caused by the instability of electron spin relaxation time. Error Includes reference signal frequency ω ref By selecting an appropriate reference frequency value, it can satisfy Δω Error =0, at which point the electron spin relaxation error is suppressed; the optimized reference frequency is selected as shown in formula (11):

[0119]

[0120] By selecting the reference frequency as described above, angular velocity error can be suppressed.

[0121] As an example, Formula 11 is the formula for selecting the reference frequency point, and Formula 12 is a simplified form of Formula 11.

[0122] Step 4: Apply a transverse reference magnetic field to stabilize the phase of the reference signal, perform precise measurement of the nucleon precession frequency, and finally obtain the angular velocity signal.

[0123] Reference Figure 4 As shown, the demodulation result of the embedded electron paramagnetic resonance magnetometer includes... 129 Xe and 131 The Xe precession signal is used to measure the precession frequency of nuclei and to select a reference frequency.

[0124] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, because according to this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions involved are not necessarily required by this application.

[0125] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0126] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

[0127] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed in this application can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0128] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0129] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0130] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0131] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0132] The above description is only a preferred embodiment of the present invention. It should be understood that the above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention, and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, etc. made within the idea and principle of the present invention should be included within the scope of protection of the present invention.

Claims

1. A nuclear magnetic resonance angular velocity sensor system, characterized in that, include: Atomic gas cell, λ / 4 waveplate, first laser, second laser, first collimating lens, second collimating lens, first linear polarizer, second linear polarizer, triaxial magnetic field coil, oven, photodetector, magnetic shielding barrel, PBS, balanced photodetector; The atomic gas chamber serves as the atomic gas chamber of a nuclear magnetic resonance angular velocity sensor. The λ / 4 waveplate is used to provide circularly polarized pump light. The first laser: used to provide pump light for the nuclear magnetic resonance angular velocity sensor; The second laser serves as a detection light source, providing detection light. The first collimating lens is used to collimate the pump light. The second collimating lens is used to collimate the detection light. The first and second linear polarizers are used to provide linearly polarized light with stable polarization states. The triaxial magnetic field coil is used to generate a working magnetic field. The oven is used for heat insulation of the atomic gas chamber. The photodetector is used for post-bubble detection in the pump optical path. The magnetic shielding barrel is used to shield the ambient magnetic field. The PBS and the balanced photodetector together constitute a balanced differential detection module, which is used to detect magnetic field signals. By applying a static magnetic field, a modulated magnetic field, and pump light longitudinally, and applying detection light and a nuclear resonance magnetic field laterally, the nuclear magnetic resonance angular velocity sensor is put into operation. The working magnetic field includes: a static magnetic field, a modulation magnetic field, a nuclear resonance magnetic field, and a reference magnetic field.

2. A relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to claim 1, characterized in that, include: Step 1: By applying a static magnetic field, a modulation magnetic field, and pump light longitudinally to the nuclear magnetic resonance angular velocity sensor system, and applying detection light and a nuclear resonance magnetic field laterally, the nuclear magnetic resonance angular velocity sensor is put into working condition. Step 2: Obtain the nucleon precession signal, lock the nucleon precession phase using a phase-locked loop, and obtain the nucleon precession frequency; Step 3: Measure the transverse spin relaxation time of the nucleon using the FID method. Combined with the nucleon gyromagnetic ratio and precession frequency, calculate the optimized reference signal frequency using the reference frequency selection formula. The transverse spin relaxation time of nucleons is obtained by fitting the envelope curve. The formula for selecting the reference frequency is designed as formula (12): （12）； in, and Nuclei 129 Xe and nuclei 131 The transverse spin relaxation time of Xe and Nuclei 129 Xe and nuclei 131 The gyromagnetic ratio of Xe and Nuclei 129 Xe and nuclei 131 The precession frequency of Xe The resonant frequency of Rb The initial modulation magnetic field frequency, The current frequency of the modulated magnetic field. For the initial electron spin relaxation time, This is the current electron spin relaxation time; Step 4: Apply a transverse reference magnetic field to stabilize the phase of the reference signal, perform precise measurement of the nucleon precession frequency, and finally obtain the angular velocity signal.

3. The relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to claim 2, characterized in that, The nucleus includes: 129 Xe and 131 Xe.

4. The relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to claim 3, characterized in that, Since the nuclear magnetic resonance angular velocity sensor uses the nucleon precession signal to sense the angular velocity, the Bloch equation formula for the nucleon precession signal is designed as follows: （1） in: For the transverse magnetic moment of the nucleon, For the longitudinal magnetic moment of the nucleon, The nucleon gyromagnetic ratio, The nuclear resonance magnetic field applied laterally, , For the nucleon transverse spin relaxation time. It is a longitudinal static magnetic field; Solving equation (1) yields the nucleus precession signal expressions for the x and y axes, as shown in equation (2): （2） in: The x-axis magnetic moment of the nucleon. For the nucleon's y-axis magnetic moment, For the longitudinal magnetic moment of the nucleon, The nucleon gyromagnetic ratio, The amplitude of the transversely applied nucleon resonance magnetic field. The frequency of the nuclear resonance magnetic field. For the nucleon transverse spin relaxation time. It is a longitudinal static magnetic field.

5. The relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to claim 4, characterized in that, The formula for determining the precession frequency of the nucleus is designed as follows: （3） in: For longitudinal static magnetic field, Angular velocity, The effect of nuclear signal phase delay; As can be seen from the above formula (3), the instability of the longitudinal static magnetic field will affect the precession frequency of the nucleons. Therefore, it is necessary to adjust the angular velocity caused by the longitudinal static magnetic field. Measurement errors are suppressed; a dual-core-based approach is adopted. 129 Xe and 131 The Xe differential angular velocity measurement method, combined with the nucleon gyromagnetic ratio characteristics, is used to suppress the nucleon precession frequency error. The design formula (4) is shown below: （4） This binary differential method can eliminate the unstable longitudinal static magnetic field. This introduces errors and improves the accuracy of angular velocity measurement.

6. The relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to claim 5, characterized in that, Due to the phase delay of the nuclear signal The errors and the transverse spin relaxation time of the nucleons make it difficult to satisfy the nucleon gyromagnetic ratio relationship. These errors cannot be eliminated by the aforementioned two-nucleon differential method; therefore, a phase delay of the nucleon signal is required. To suppress errors.

7. The relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to claim 6, characterized in that, The nuclear magnetic resonance angular velocity sensor uses an embedded electron paramagnetic resonance magnetometer to measure the precession frequency of the nuclei. According to the Bloch equation, the electron magnetic moment signal can be obtained, as shown in formula (5). （5） Among them: This is the electronic magnetic moment signal. The current electron spin relaxation time, The z-axis electron magnetic moment, Let Rb be the gyromagnetic ratio. Let be the Bessel function, and its coefficients be... , To modulate the magnetic field amplitude, The current frequency of the modulated magnetic field; Considering the application of a transverse reference magnetic field The signal form at that time is used for the analysis of nuclear precession signals.

8. The relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to claim 7, characterized in that, To achieve nucleon resonance, a nucleon resonance magnetic field needs to be applied along the x-axis. In this case, the x-axis magnetic field signal contains both the nucleon resonance magnetic field and the nucleon precession signal, while the y-axis magnetic field signal contains only the nucleon precession signal. The nucleon signal phase is measured by extracting the y-axis nucleon signal phase. By demodulating formula (5) once, the y-axis magnetic field signal can be obtained, as shown in formula (6); （6） Solving equation (6) yields the reference magnetic field. The phase information; a demodulation process is used to detect the nucleon precession phase and the reference signal phase.

9. The relaxation error suppression method for a nuclear magnetic resonance angular velocity sensor system according to claim 8, characterized in that, The precession frequency of the nucleon is equal to the nucleon resonance frequency, and the phase delay of the nucleon signal satisfies... The phase of the measured signal is related to the frequency of the applied magnetic field signal, and the phase measurement values ​​corresponding to magnetic field signals of different frequencies are different; as shown in formula (7): （7） in: The resonant frequency of Rb The initial modulation magnetic field frequency, For the initial electron spin relaxation time, The resonant frequency is 129Xe. A phase delay of 129Xe, The resonant frequency is 131Xe. The phase delay is 131Xe; the above phase signals are the phase measurement values ​​of each parameter obtained after the first demodulation of the electron magnetic moment; the phase signals of 129Xe and 131Xe are used as the phase input of the phase-locked loop for nucleon precession frequency measurement, and the reference signal phase is used to suppress the phase error of the electron paramagnetic resonance magnetometer. During the measurement process, parameter instability typically occurs in the longitudinal static magnetic field. and the current electron spin relaxation time In this process, the reference phase is locked by adjusting... Achieve this by adjusting the longitudinal static magnetic field fluctuations. This can suppress longitudinal static magnetic field errors and eliminate measurement signal phase errors caused by longitudinal static magnetic field instability; however, when the electron spin relaxation time changes, the reference phase will also be altered to achieve stability. ; Due to the inconsistency between the reference signal and the precession frequency of the nucleons... 129 Xe and 131 The phase measurement error of Xe still exists, and the detected nucleon precession phase signal is as shown in formula (8): （8） The aforementioned phase signals are the actual measured 129Xe and 131Xe phase values ​​when there is electron spin relaxation time instability. The precession frequency of the nucleon is obtained through a phase-locked loop scheme. The phase error measured by the electron paramagnetic resonance magnetometer is considered to be the phase delay of the nucleon signal. The nucleon phase delay error when the electron spin relaxation time changes is shown in formula (9): The phase of the measured reference signal satisfies: ； （9） The above-mentioned nucleon phase delay error is substituted into formula (3) for the calculation of nucleon precession frequency error; Nucleon phase delay error will cause nucleon precession frequency shift, which will eventually lead to angular velocity measurement error, as shown in formula (10): （10）； The above formula is used to represent the angular velocity measurement error caused by the electron paramagnetic resonance magnetometer. By making the angular velocity measurement error zero, the error can be suppressed. Angular velocity measurement error caused by electron spin relaxation time instability Includes reference frequency By selecting an appropriate reference frequency value, it can be made to meet the requirements. At this point, the electron spin relaxation error is suppressed; the optimized reference frequency is shown in formula (11): （11）； By selecting the reference frequency as described above, angular velocity error can be suppressed.

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