Gyroscope inert gas isotopic transverse relaxation time on-line measuring device

Abstract

The application provides a kind of gyro inert gas isotopes transverse relaxation time on-line measurement device, the device includes first control loop, second control loop and third control loop;Wherein, first control loop is used to control 131 Xe excitation magnetic field frequency implementation 131 Xe resonance state maintenance;Second control loop is used to control 129 Xe excitation magnetic field frequency implementation 129 Xe resonance state maintenance;Third control loop is used to control static magnetic field implementation 131 Xe / 129 Xe resonance maintenance frequency f1+f2=f0;The device can be used 129 Xe / 131 Xe combination transverse relaxation time measurement, also can be used Xe / Kr, 199 Hg / 201 Hg combination transverse relaxation time measurement.

Description

Technical Field

[0001] This application belongs to the field of nuclear magnetic resonance gyroscope technology, specifically relating to an online measurement device for the transverse relaxation time of inert gas isotopes in a gyroscope. Background Technology

[0002] Nuclear magnetic resonance (NMR) gyroscopes are miniature navigation-grade gyroscopes that primarily determine the carrier's angular velocity by detecting the precession frequency changes of inert gas isotopes within an atomic gas chamber in a magnetic field. They are characterized by their small size, low power consumption, and low cost. The transverse relaxation time of the inert gas within the atomic gas chamber is one of the key factors limiting gyroscope performance improvement. On one hand, the magnitude of the transverse relaxation time itself limits the gyroscope's resonance frequency locking accuracy, thus limiting gyroscope precision. On the other hand, the relaxation time matching between inert gas isotopes affects the differential effect against environmental magnetic field interference. Therefore, precise measurement of the inert gas relaxation time within the atomic gas chamber is essential.

[0003] However, current common methods for measuring transverse relaxation time primarily utilize the FID (Flexible Interference Device) and its variants. This method involves instantaneously removing the excitation magnetic field after inert gas precession excitation and measuring the free decay of the inert gas's transverse magnetic moment to determine the transverse relaxation time. This method eliminates the influence of the excitation magnetic field on the measurement results and can evaluate the polarization and decay of the inert gas under ideal conditions. However, in practical applications, to ensure continuous gyroscope output, it is impossible to switch the excitation magnetic field on and off. Theoretical studies show that the presence of the excitation magnetic field broadens the inert gas resonance spectrum, thereby reducing the actual relaxation time.

[0004] In summary, the current mature FID scheme is insufficient to accurately evaluate the transverse relaxation time in the atomic gas chamber of a nuclear magnetic resonance gyroscope. A novel measurement scheme is needed to achieve online measurement of the transverse relaxation time of the inert gas in the atomic gas chamber. Summary of the Invention

[0005] The purpose of this invention is to realize the inert gas isotope control of a nuclear magnetic resonance gyroscope through a closed-loop control system. 131 Xe / 129 Xe is a closed loop, and then f1 + f2 = f0 is achieved by adjusting the static magnetic field B0. (Fixed) 131 Xe locked phase θ 131 Change gradually 129 Xe locked phase θ 129 A series of static magnetic field values ​​B0 were obtained, and B0~θ were plotted. 129 The curve can be determined by fitting it. 129 Xe Relaxation Time T2 129Xe .fixed 129 Xe phase-locked reference θ 129 Change gradually 131Xe phase-locked reference θ 131 A series of static magnetic field values ​​B0 were obtained, and B0~θ were plotted. 129 The curve can be determined by fitting it. 131 Xe Relaxation Time T2 131Xe The above scheme does not involve switching the excitation magnetic field on or off during operation, thus enabling accurate measurement of the transverse relaxation time.

[0006] This application provides an online measurement device for the transverse relaxation time of gyroscope inert gas isotopes, the device comprising a first control loop, a second control loop, and a third control loop;

[0007] The first control loop is used for control. 131 Xe excitation magnetic field frequency realization 131 Xe resonance state maintained;

[0008] The second control loop is used for control. 129 Xe excitation magnetic field frequency realization 129 Xe resonance state maintained;

[0009] The third control loop is used to control the static magnetic field. 131 Xe / 129 The Xe resonance sustaining frequency is f1+f2=f0.

[0010] Preferably, the device can be used 129 Xe / 131 Xe combined transverse relaxation time measurement, can also be used for Xe / Kr, 199 Hg / 201 Measurement of transverse relaxation time of Hg combination.

[0011] Preferably, fixed 131 Xe phase feedback benchmark, plotting 129 The relationship curve between Xe phase feedback reference and static magnetic field actuation value is obtained. 129 Xe lateral relaxation time; fixed 129 Xe phase feedback benchmark, plotting 131 The relationship curve between Xe phase feedback reference and static magnetic field actuation value is obtained. 131 Xe lateral relaxation time.

[0012] Preferably, the first control loop consists of a frequency generation system, an analog amplification module, a gyroscope x-axis magnetic field coil, a detection system, a phase detection system, and a phase feedback system.

[0013] Preferably, the second control system consists of a frequency generation system, an analog amplification module, a gyroscope x-axis magnetic field coil, a detection system, a phase detection system, and a phase feedback system.

[0014] Preferably, the third control system consists of a frequency generation system, an analog amplification module, a detection system, a multiplier, a phase detection system, and a magnetic field actuation feedback system.

[0015] Preferably, the AC frequency generated by the frequency generation system is converted from digital to analog and then amplified, and then split into two paths. One signal is applied to the excitation magnetic field coil of the gyroscope's x-axis, and the other signal enters the phase detection system and the atomic gas chamber. 131 Xe, driven by the excitation magnetic field, begins to precess around the static magnetic field B0; the detection system is used to... 131 The Xe lateral precession component signal is converted into an electrical signal and input to the phase detection system. The phase detection system performs phase detection on the two input signals and outputs the corresponding phase difference to the phase feedback system. The phase feedback system feeds back the corresponding phase error to the frequency generation system using the corresponding PID algorithm.

[0016] Preferably, the detection system detects 131 Xe / 129 The Xe lateral precession signal and the f1+f2 and f1-f2 signals generated after multiplication are input to the input terminal of the phase detection system.

[0017] The frequency generation system generates a preset frequency f0, which is then converted from digital to analog and amplified before being input to the other end of the phase detection system.

[0018] The phase detection system performs phase detection on the two input signals and outputs the corresponding phase difference / frequency difference to the magnetic field actuation feedback system. The magnetic field actuation feedback system feeds back the corresponding phase error to the gyroscope static magnetic field generation module using the corresponding PID algorithm, so as to stabilize the resonance frequency and value of the inert gas isotope to f0.

[0019] Advantages of this invention:

[0020] This invention provides an online measuring device for measuring the transverse relaxation time of inert gas in a nuclear magnetic resonance gyroscope. The inert gas isotopes inside the gyroscope are measured through a closed-loop control system. 131 Xe / 129 Xe is a closed loop, and then f1 + f2 = f0 is achieved by adjusting the static magnetic field B0. (Fixed) 131 Xe locked phase θ 131 Change gradually 129 Xe locked phase θ 129 A series of static magnetic field values ​​B0 were obtained, and B0~θ were plotted. 129 The curve can be determined by fitting it. 129 Xe Relaxation Time fixed 129 Xe phase-locked reference θ 129 Change gradually 131Xe phase-locked reference θ 131 A series of static magnetic field values ​​B0 were obtained, and B0~θ were plotted. 129 The curve can be determined by fitting it. 131 Xe Relaxation Time

[0021] The above-described scheme does not involve switching the excitation magnetic field on or off during operation. Compared with the currently used FID method, the scheme designed in this invention can accurately measure the actual value of the transverse relaxation time of the inert gas in the atomic gas chamber under continuous transverse excitation, effectively supporting the optimization of dual-nucleus control parameters in the design of gyroscope closed-loop control systems and improving performance. 129 Xe / 131 Xe output signal synchronization. Furthermore, this scheme can be used to analyze the influence of the transverse excitation magnetic field amplitude on the relaxation time, providing experimental basis for optimizing the excitation magnetic field. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the online measurement device for the transverse relaxation time of inert gas isotopes in a nuclear magnetic resonance gyroscope according to the present invention;

[0023] Figure 2 This is a schematic diagram of the basic structure of the first control loop 1 of the present invention;

[0024] Figure 3 This is a schematic diagram of the basic structure of the second control loop 2 of the present invention;

[0025] Figure 4 This is a schematic diagram of the basic structure of the second control loop 3 of the present invention;

[0026] Figure 5 This is the curve showing the relationship between the static magnetic field actuation value ΔB and the phase feedback reference change value of this invention. Detailed Implementation

[0027] This invention belongs to the field of nuclear magnetic resonance gyroscope technology, and discloses an online measurement device and method for the transverse relaxation time of inert gas isotopes in an atomic gas chamber. It includes a first control loop 1, a second control loop 2, and a third control loop, wherein the first control loop is used to control... 131 Xe excitation magnetic field frequency realization 131 Xe resonance state maintained; second control loop used for control 129 Xe excitation magnetic field frequency realization 129 Xe resonance state is maintained; the third control loop is used to control the static magnetic field to achieve... 131 Xe / 129The Xe resonance sustaining frequency f1+f2=f0, and the scheme designed in this invention can accurately measure the actual value of the transverse relaxation time of the inert gas in the atomic gas chamber under transverse continuous excitation, effectively supporting the optimization of dual-nucleus control parameters in the design of gyroscope closed-loop control systems, and improving... 129 Xe / 131 Xe output signal synchronization. Furthermore, this scheme can be used to analyze the influence of the transverse excitation magnetic field amplitude on the relaxation time, providing experimental basis for optimizing the excitation magnetic field.

[0028] This application provides an online measurement device for the transverse relaxation time of gyroscope inert gas isotopes, the device comprising a first control loop, a second control loop, and a third control loop;

[0029] The first control loop is used for control. 131 Xe excitation magnetic field frequency realization 131 Xe resonance state maintained; second control loop used for control 129 Xe excitation magnetic field frequency realization 129 Xe resonance state is maintained; the third control loop is used to control the static magnetic field to achieve... 131 Xe / 129 The Xe resonance sustaining frequency is f1+f2=f0.

[0030] The device can be used 129 Xe / 131 Xe combined transverse relaxation time measurement, can also be used for Xe / Kr, 199 Hg / 201 Measurement of transverse relaxation time of Hg combination.

[0031] fixed 131 Xe phase feedback benchmark, plotting 129 The relationship curve between Xe phase feedback reference and static magnetic field actuation value is obtained. 129 Xe lateral relaxation time; fixed 129 Xe phase feedback benchmark, plotting 131 The relationship curve between Xe phase feedback reference and static magnetic field actuation value is obtained. 131 Xe lateral relaxation time.

[0032] Available for 129 Xe / 131 Xe combined transverse relaxation time measurement, can also be used for Xe / Kr, 199 Hg / 201 Measurement of transverse relaxation time using Hg and other combinations.

[0033] The first control loop consists of a frequency generation system 4, an analog amplification module 5, a gyroscope x-axis magnetic field coil 6, a detection system 7, a phase detection system 8, and a phase feedback system 9.

[0034] The second control system consists of a frequency generation system 10, an analog amplification module 11, a gyroscope x-axis magnetic field coil 6, a detection system 7, a phase detection system 12, and a phase feedback system 13.

[0035] The third control system consists of a frequency generation system 14, an analog amplification module 15, a detection system 7, a multiplier 16, a phase detection system 17, and a magnetic field actuation feedback system 18.

[0036] Frequency generation system 4 generates an AC frequency, which, after digital-to-analog conversion and analog amplification 5, is split into two paths. One signal is applied to the gyroscope's x-axis excitation magnetic field coil 6, and the other signal enters the phase detection system 8. (Atomic gas chamber) 131 Driven by the excitation magnetic field, Xe begins to precess around the static magnetic field B0. The detection system 7 is used to... 131 The Xe lateral precession component signal is converted into an electrical signal and input to the phase detection system. The phase detection system 8 performs phase detection on the two input signals and outputs the corresponding phase difference to the phase feedback system 9. The phase feedback system feeds back the corresponding phase error to the frequency generation system 4 using the corresponding PID algorithm.

[0037] The frequency generation system 10 generates an AC frequency, which, after digital-to-analog conversion and analog amplification 11, is split into two paths. One signal is applied to the gyroscope excitation coil, and the other signal enters the phase detection system 12. (Atomic gas chamber) 129 Driven by the excitation magnetic field, Xe begins to precess around the static magnetic field B0. The first control system and the second control system share the gyroscope x-axis magnetic field coil 6 and the detection system 7. The detection system 7 is used to... 129 The Xe lateral precession component signal is converted into an electrical signal and input to the phase detection system. The phase detection system 12 performs phase detection on the two input signals and outputs the corresponding phase difference to the phase feedback system 13. The phase feedback system 13 feeds back the corresponding phase error to the frequency generation system 10 using a corresponding PID algorithm.

[0038] Detection system 7 detected 131 Xe / 129 The Xe transverse precession signal, after being multiplied by 16, generates f1+f2 and f1-f2 signals, which are then input to the input of the phase detection system 17. The frequency generation system generates a pre-set frequency f0, which, after digital-to-analog conversion and analog amplification, is input to the other end of the phase detection system 17. The phase detection system 17 performs phase detection on the two input signals and outputs the corresponding phase difference / frequency difference to the magnetic field actuation feedback system 18. The magnetic field actuation feedback system 18 uses a corresponding PID algorithm to feed back the corresponding phase error to the gyroscope static magnetic field generation module, stabilizing the resonant frequency and value of the inert gas isotopes to f0.

[0039] The phase detection system can be implemented using a square wave delay measurement scheme or a modulation / demodulation + low-pass scheme to extract the phase difference.

[0040] Phase feedback systems 7 and 10 can act on the frequency control terminal of the frequency generation system through frequency feedback, and can also act on the phase accumulation terminal of the frequency generation system through phase feedback.

[0041] In other embodiments of this application, an online measuring device for measuring the transverse relaxation time of an inert gas for a nuclear magnetic resonance gyroscope is provided, comprising a first closed-loop control system 1, a second closed-loop control system 2, and a third closed-loop control system 3.

[0042] The first control system consists of a frequency generation system 4, an analog amplification module 5, a gyroscope x-axis magnetic field coil 6, a detection system 7, a phase detection system 8, and a phase feedback system 9; it is mainly used to achieve... 131 The Xe resonant closed loop, frequency generation system 4 generates an AC frequency, which is then converted from digital to analog and amplified by analog signal 5 before being split into two paths. One signal is applied to the gyroscope's x-axis excitation magnetic field coil 6, and the other signal enters the phase detection system 8. (Atomic gas chamber) 131 Driven by the excitation magnetic field, Xe begins to precess around the static magnetic field B0. The detection system 7 is used to... 131 The Xe lateral precession component signal is converted into an electrical signal and input to the phase detection system. The phase detection system 8 performs phase detection on the two input signals and outputs the corresponding phase difference to the phase feedback system 9. The phase feedback system feeds back the corresponding phase error to the frequency generation system 4 using the corresponding PID algorithm.

[0043] The second control system consists of a frequency generation system 10, an analog amplification module 11, a gyroscope x-axis magnetic field coil 6, a detection system 7, a phase detection system 12, and a phase feedback system 13; it is mainly used to achieve... 129 The Xe resonant closed loop, frequency generation system 10 generates an AC frequency, which is then converted from digital to analog and amplified by analog signal 11 before being split into two paths. One signal is applied to the gyroscope excitation coil, and the other signal enters the phase detection system 12. (Atomic gas chamber) 129 Driven by the excitation magnetic field, Xe begins to precess around the static magnetic field B0. The first control system and the second control system share the gyroscope x-axis magnetic field coil 6 and the detection system 7. The detection system 7 is used to... 129 The Xe lateral precession component signal is converted into an electrical signal and input to the phase detection system. The phase detection system 12 performs phase detection on the two input signals and outputs the corresponding phase difference to the phase feedback system 13. The phase feedback system 13 feeds back the corresponding phase error to the frequency generation system 10 using a corresponding PID algorithm.

[0044] The third control system consists of a frequency generation system 14, an analog amplification module 15, a detection system 7, a multiplier 16, a phase detector system 17, and a magnetic field actuation feedback system 18; the detection system 7 detects... 131 Xe / 129 The Xe transverse precession signal, after being multiplied by 16, generates f1+f2 and f1-f2 signals, which are then input to the input of the phase detection system 17. The frequency generation system generates a pre-set frequency f0, which, after digital-to-analog conversion and analog amplification, is input to the other end of the phase detection system 17. The phase detection system 17 performs phase detection on the two input signals and outputs the corresponding phase difference / frequency difference to the magnetic field actuation feedback system 18. The magnetic field actuation feedback system 18 uses a corresponding PID algorithm to feed back the corresponding phase error to the gyroscope static magnetic field generation module, stabilizing the resonant frequency and value of the inert gas isotopes to f0.

[0045] After the first, second, and third control systems are functioning normally, the inert gas isotope resonance frequencies f1 and f2 respectively satisfy...

[0046]

[0047] f1 + f2 = f0

[0048] Fixed first feedback system phase feedback reference Change the phase feedback reference of the second feedback system Record the corresponding 131 Xe / 129 The Xe resonant frequency is f1 / f2, and the static magnetic field actuation value is ΔB. 129 The relationship between the Xe relaxation time and the change in the phase feedback reference should satisfy:

[0049]

[0050] During the phase-locking phase, the system is generally chosen to be near resonance, i.e. Approaching zero, the above formula can be simplified to:

[0051]

[0052] The phase reference change Δθ is linearly related to the static magnetic field feedback value, with a proportionality coefficient of 1. 129 Xe is the reciprocal of the transverse relaxation time. Based on the above theoretical analysis, the compensation is set as Δθ, and the phase feedback reference of the second feedback system is changed. By plotting the curve relating the static magnetic field actuation value ΔB to the change in the phase feedback reference value, and performing linear fitting on it, the following can be obtained: 129 Xe lateral relaxation time.

[0053] and 129The Xe transverse relaxation time measurement scheme is the same, with a fixed phase feedback reference for the second feedback system. The compensation is set to Δθ, changing the phase feedback reference of the first feedback system. By plotting the curve relating the static magnetic field actuation value ΔB to the change in the phase feedback reference value, and performing linear fitting on it, the following can be obtained: 131 Xe lateral relaxation time.

[0054] In other embodiments of this application, the following description is in conjunction with the appendix. Figure 1 -Appendix Figure 5 The technical solution of the present invention will be described in detail below.

[0055] This invention provides an online measurement device and method for the transverse relaxation time of inert gas in a nuclear magnetic resonance gyroscope. The inert gas isotopes inside the gyroscope are measured through a closed-loop control system. 131 Xe / 129 Xe is a closed loop, and then f1 + f2 = f0 is achieved by adjusting the static magnetic field B0. (Fixed) 131 Xe locked phase θ 131 Change gradually 129 Xe locked phase θ 129 A series of static magnetic field values ​​B0 were obtained, and B0~θ were plotted. 129 The curve can be determined by fitting it. 129 Xe Relaxation Time fixed 129 Xe phase-locked reference θ 129 Change gradually 131 Xe phase-locked reference θ 131 A series of static magnetic field values ​​B0 were obtained, and B0~θ were plotted. 129 The curve can be determined by fitting it. 131 Xe Relaxation Time The above scheme does not require switching the excitation magnetic field on or off during operation, thus enabling accurate measurement of the transverse relaxation time.

[0056] Please also refer to Figure 1 , Figure 1 This is a schematic diagram of an online test measurement device for the transverse relaxation time of an inert gas in a nuclear magnetic resonance gyroscope. The device, characterized by comprising a first control loop 1, a second control loop 2, and a third control loop, is used to control... 131 Xe excitation magnetic field frequency realization 131 Xe resonance state maintained; second control loop used for control 129 Xe excitation magnetic field frequency realization 129 Xe resonance state is maintained; the third control loop is used to control the static magnetic field to achieve... 131Xe / 129 The Xe resonance sustaining frequency is f1+f2=f0.

[0057] Please also refer to Figure 2 , Figure 2 This is the basic structure of the first control loop 1. The first control system consists of a frequency generation system 4, an analog amplification module 5, a gyroscope x-axis magnetic field coil 6, a detection system 7, a phase detection system 8, and a phase feedback system 9; it is mainly used to achieve... 131 The Xe resonant closed loop, frequency generation system 4 generates an AC frequency, which is then converted from digital to analog and amplified by analog signal 5 before being split into two paths. One signal is applied to the gyroscope's x-axis excitation magnetic field coil 6, and the other signal enters the phase detection system 8. (Atomic gas chamber) 131 Driven by the excitation magnetic field, Xe begins to precess around the static magnetic field B0. The detection system 7 is used to... 131 The Xe lateral precession component signal is converted into an electrical signal and input to the phase detection system. The phase detection system 8 performs phase detection on the two input signals and outputs the corresponding phase difference to the phase feedback system 9. The phase error of the phase feedback system 9 is fed back to the frequency generation system 4 using a corresponding PID algorithm.

[0058] The phase feedback system 9 can act on the frequency control terminal of the frequency generation system through frequency feedback, and it can also act on the phase accumulation terminal of the frequency generation system through phase feedback.

[0059] Please also refer to Figure 3 , Figure 3 This is the basic structure of the second control loop 2. The second control system consists of a frequency generation system 10, an analog amplification module 11, a gyroscope x-axis magnetic field coil 6, a detection system 7, a phase detection system 12, and a phase feedback system 13; it is mainly used to achieve... 129 The Xe resonant closed loop, frequency generation system 10 generates an AC frequency, which is then converted from digital to analog and amplified by analog signal 11 before being split into two paths. One signal is applied to the gyroscope excitation coil, and the other signal enters the phase detection system 12. (Atomic gas chamber) 129 Driven by the excitation magnetic field, Xe begins to precess around the static magnetic field B0. The first control system and the second control system share the gyroscope x-axis magnetic field coil 6 and the detection system 7. The detection system 7 is used to... 129 The Xe lateral precession component signal is converted into an electrical signal and input to the phase detection system. The phase detection system 12 performs phase detection on the two input signals and outputs the corresponding phase difference to the phase feedback system 13. The phase feedback system 13 feeds back the corresponding phase error to the frequency generation system 10 using a corresponding PID algorithm.

[0060] Please also refer to Figure 4 , Figure 4This is the basic structure of the third control loop 4. The third control system consists of a frequency generation system 14, an analog amplification module 15, a detection system 7, a multiplier 16, a phase detector system 17, and a magnetic field actuation feedback system 18; the detection system 7 detects... 131 Xe / 129 The Xe transverse precession signal, after being multiplied by 16, generates f1+f2 and f1-f2 signals, which are then input to the input of the phase detection system 17. The frequency generation system generates a pre-set frequency f0, which, after digital-to-analog conversion and analog amplification, is input to the other end of the phase detection system 17. The phase detection system 17 performs phase detection on the two input signals and outputs the corresponding phase difference / frequency difference to the magnetic field actuation feedback system 18. The magnetic field actuation feedback system 18 uses a corresponding PID algorithm to feed back the corresponding phase error to the gyroscope static magnetic field generation module, stabilizing the resonant frequency and value of the inert gas isotopes to f0.

[0061] After the first, second, and third control systems are functioning normally, the inert gas isotope resonance frequencies f1 and f2 respectively satisfy...

[0062]

[0063] f1 + f2 = f0

[0064] Fixed first feedback system phase feedback reference Change the phase feedback reference of the second feedback system Record the corresponding 131 Xe / 129 The Xe resonant frequency is f1 / f2, and the static magnetic field actuation value is ΔB. 129 The relationship between the Xe relaxation time and the change in the phase feedback reference should satisfy:

[0065]

[0066] During the phase-locking phase, the system is generally chosen to be near resonance, i.e. Approaching zero, the above formula can be simplified to:

[0067]

[0068] The phase reference change Δθ is linearly related to the static magnetic field feedback value, with a proportionality coefficient of 1. 129 Xe is the reciprocal of the transverse relaxation time. Based on the above theoretical analysis, the compensation is set as Δθ, and the phase feedback reference of the second feedback system is changed. By plotting the curve relating the static magnetic field actuation value ΔB to the change in phase feedback reference value, and performing linear fitting on it, the following can be obtained: 129 Xe lateral relaxation time.

[0069] and129 The Xe transverse relaxation time measurement scheme is the same, with a fixed phase feedback reference for the second feedback system. The compensation is set to Δθ, changing the phase feedback reference of the first feedback system. By plotting the curve relating the static magnetic field actuation value ΔB to the change in phase feedback reference value, and performing linear fitting on it, the following can be obtained: 131 Xe lateral relaxation time.

[0070] Implementation Case 1

[0071] In this embodiment, an alkali metal is used to fill the 5mm×5mm×5mm atomic gas cell. 87 Rb、 129 Xe, 131 Xe and buffer gas N2 were used to measure the relaxation time of the inert gas using FID. The measurement results were as follows: 131 Xe lateral relaxation time is 12s. 131 The Xe transverse relaxation time is 15.6 s. The measurement results of this invention are... 131 Xe lateral relaxation time is 11s. 131 The Xe transverse relaxation time is 12.4 s, and the measurement result increases as the amplitude of the transverse excitation magnetic field decreases, gradually approaching the FID measurement result.

[0072] Implementation Case 2

[0073] In this embodiment, the 15mm×15mm×15mm atomic gas cell is filled with alkali metal. 87 Rb、 129 Xe, 131 Xe and buffer gas N2 were used to measure the relaxation time of the inert gas using FID. The measurement results were as follows: 131 Xe lateral relaxation time is 24s. 131 Xe transverse relaxation time is 28 s. The measurement results of this invention are as follows: 131 Xe lateral relaxation time is 16s. 131 The Xe transverse relaxation time is 18s, and the measurement result decreases as the amplitude of the transverse excitation magnetic field increases, gradually approaching the FID measurement result.

[0074] Implementation Case 3

[0075] In this embodiment, an alkali metal is used to fill the 5mm×5mm×5mm atomic gas cell. 133 Cs、 129 Xe, 131 Xe and buffer gas N2 were used to measure the relaxation time of the inert gas using FID. The measurement results were as follows: 131 Xe lateral relaxation time: 7s 129 Xe transverse relaxation time 4s. The measurement result of this invention is... 131 Xe lateral relaxation time: 5s131 The Xe transverse relaxation time is 2s, and the measurement result decreases as the transverse excitation magnetic field amplitude increases, gradually approaching the FID measurement result.

Claims

1. An online measurement device for the transverse relaxation time of a gyroscope inert gas isotope, characterized in that, The device includes a first control loop, a second control loop, and a third control loop; The first control loop is used for control. 131 Xe excitation magnetic field frequency realization 131 Xe resonance state maintained; The second control loop is used for control. 129 Xe excitation magnetic field frequency realization 129 Xe resonance state maintained; The third control loop is used to control the static magnetic field. 131 Xe / 129 The Xe resonance sustaining frequency is f1+f2=f0.

2. The apparatus according to claim 2, characterized in that, The device can be used 129 Xe / 131 Xe combined transverse relaxation time measurement, can also be used for Xe / Kr, 199 Hg / 201 Measurement of transverse relaxation time of Hg combination.

3. The apparatus according to claim 2, characterized in that, fixed 131 Xe phase feedback benchmark, plotting 129 The relationship curve between Xe phase feedback reference and static magnetic field actuation value is obtained. 129 Xe lateral relaxation time; fixed 129 Xe phase feedback benchmark, plotting 131 The relationship curve between Xe phase feedback reference and static magnetic field actuation value is obtained. 131 Xe lateral relaxation time.

4. The apparatus according to claim 3, characterized in that, The first control loop consists of a frequency generation system, an analog amplification module, a gyroscope x-axis magnetic field coil, a detection system, a phase detection system, and a phase feedback system.

5. The apparatus according to claim 4, characterized in that, The second control system consists of a frequency generation system, an analog amplification module, a gyroscope x-axis magnetic field coil, a detection system, a phase detection system, and a phase feedback system.

6. The apparatus according to claim 5, characterized in that, The third control system consists of a frequency generation system, an analog amplification module, a detection system, a multiplier, a phase detection system, and a magnetic field actuation feedback system.

7. The apparatus according to claim 6, characterized in that, The frequency generation system generates an AC frequency, which, after digital-to-analog conversion and analog amplification, is split into two paths. One signal is applied to the gyroscope's x-axis excitation magnetic field coil, while the other signal enters the phase detection system and the atomic gas chamber. 131 Xe, driven by the excitation magnetic field, begins to precess around the static magnetic field B0; the detection system is used to... 131 The Xe lateral precession component signal is converted into an electrical signal and input to the phase detection system. The phase detection system performs phase detection on the two input signals and outputs the corresponding phase difference to the phase feedback system. The phase feedback system feeds back the corresponding phase error to the frequency generation system using the corresponding PID algorithm.

8. The apparatus according to claim 7, characterized in that, The detection system detected 131 Xe / 129 The Xe lateral precession signal and the f1+f2 and f1-f2 signals generated after multiplication are input to the input terminal of the phase detection system. The frequency generation system generates a preset frequency f0, which is then converted from digital to analog and amplified before being input to the other end of the phase detection system. The phase detection system performs phase detection on the two input signals and outputs the corresponding phase difference / frequency difference to the magnetic field actuation feedback system. The magnetic field actuation feedback system feeds back the corresponding phase error to the gyroscope static magnetic field generation module using the corresponding PID algorithm, so as to stabilize the resonance frequency and value of the inert gas isotope to f0.

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