Multi-parameter in-situ measurement method for serf gyroscope based on transverse magnetic field resonance

Abstract

The SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance first measures the amplitude-frequency characteristic curve of SERF atomic spin gyroscope Bx, By alternating current magnetic field response, then finds the resonance frequency and resonance amplitude value corresponding to the alkali metal electron resonance peak in x and y directions respectively, and finally constructs an equation through the ratio of the resonance frequency and resonance amplitude value corresponding to the alkali metal electron resonance peak in x and y directions, and obtains the accurate values of the electron magnetic field, the slowing factor and the electron transverse relaxation rate through the global optimization function algorithm. The present application can realize the in-situ accurate measurement of the electron magnetic field, the nuclear magnetic field, the electron polarizability, the nuclear polarizability, the slowing factor and the electron transverse relaxation rate of the SERF atomic spin gyroscope without changing the system state.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gyroscope parameter measurement, and particularly relates to a SERF gyroscope multi-parameter in-situ measurement method based on a transverse magnetic field resonance. BACKGROUND

[0002] The SERF atomic spin gyroscope has an ultra-high theoretical angular velocity measurement sensitivity, and the theoretical sensitivity can reach 10 -8° / s / Hz 1 / 2 orders of magnitude, which is far higher than that of other types of gyroscopes.

[0003] The research and development of the SERF atomic spin gyroscope are of great significance in inertial navigation and exploration of frontier physics problems. SUMMARY

[0004] The technical solution of the present application is: in view of the defects or deficiencies of the prior art, a SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance is provided, through measurement of the amplitude-frequency response curve of the transverse alternating magnetic field, the resonance frequency and resonance amplitude of the Bx and By resonance peaks are obtained, a multi-element high-order nonlinear equation set is constructed, the global optimal function algorithm is used to obtain the electronic magnetic field, the slowing factor and the electronic transverse relaxation rate, the nuclear magnetic field is obtained through the gyroscope compensation point, the electronic polarizability and the nuclear polarizability are obtained by using the alkali metal electron spin equivalent magnetic field formula and the inert gas nuclear spin equivalent magnetic field formula, and under the premise of not destroying the original state of the SERF atomic spin gyroscope, the multi-parameter in-situ accurate measurement of the SERF atomic spin gyroscope is realized.

[0005] The technical solution of the present application is as follows:

[0006] The SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance has the characteristics that it comprises the following steps:

[0007] Step 1, an alternating magnetic field B x is applied in the x direction, a first amplitude-frequency characteristic curve of the B x alternating magnetic field response is obtained, an alternating magnetic field B y is applied in the y direction, a second amplitude-frequency characteristic curve of the B y alternating magnetic field response is obtained;

[0008] Step 2, the resonance frequency ωBx and the resonance amplitude FBx of the alkali metal electron resonance peak in the x direction are read through the first amplitude-frequency characteristic curve, and the resonance frequency ωBy and the resonance amplitude FBy of the alkali metal electron resonance peak in the y direction are read through the second amplitude-frequency characteristic curve;

[0009] Step 3, a three-element high-order nonlinear equation set is constructed through ωBx, FBx, ωBy and FBy;

[0010] Step 4, the equation set is solved by using the global optimal function algorithm, and the electronic magnetic field Be, the slowing factor Q and the electronic transverse relaxation rate

[0011] Step 5, the nuclear magnetic field Bn is calculated from the gyroscope compensation point Bc and the electronic magnetic field Be, and the electronic polarizability and the nuclear polarizability

[0012] The step 1 comprises: heating the SERF atomic spin gyroscope alkali metal cell to the working temperature, when the laser polarizes the atoms to the steady state, the magnetic field cross modulation compensation technology is used to compensate the magnetic field, at this time the gyroscope works at the "gyroscope compensation point Bc", which satisfies Bc=-Be-Bn, the SERF atomic spin gyroscope is fixed in the inertial space static state, the alternating magnetic field with the amplitude of 0.3nT and the frequency of 0.01Hz-400Hz is respectively applied to the x-axis and y-axis, the amplitude of the magnetic field response at different frequencies is obtained, the frequency-peak-to-peak value curve is drawn, and the B x 、B y amplitude-frequency characteristic curve of the alternating magnetic field response is obtained through the magnetic field transfer function fitting.

[0013] The ternary high-order nonlinear equation group in the step 3 is as follows:

[0014]

[0015] Wherein, KFByx is the amplitude square ratio, which is the ratio of the square of the y-axis resonance peak amplitude to the square of the x-axis resonance peak amplitude, γ e =28nT / Hz is the electron gyromagnetic ratio.

[0016] The step 4 comprises: taking the ternary high-order nonlinear equation group obtained from the step 3 as the constraint condition, and setting the objective function error as follows:

[0017]

[0018] Wherein, is the electron resonance equation group,

[0019]

[0020] The global minimum value satisfying the objective function is obtained through the global optimal function algorithm, and the result is the electron magnetic field Be, the slowing down factor Q, and the electron transverse relaxation rate

[0021] The step 5 comprises: Bn=-Bc-Be

[0022] Through the alkali metal electron spin equivalent magnetic field formula And the inert gas nucleus spin equivalent magnetic field formula The following is obtained:

[0023]

[0024]

[0025] Wherein, λ is an intermediate quantity of the simplified equation, κ0 is the Fermi contact constant, Me and M n are the magnetization intensities produced when the alkali metal electron spin and the noble gas nuclear spin are fully polarized, and both are known values.

[0026] The technical effects of the present invention are as follows: The present invention is based on the SERF gyroscope multi-parameter in-situ measurement method of transverse magnetic field resonance, and obtains B by measuring the transverse AC magnetic field amplitude-frequency response curve. x 、B y The resonant frequency and amplitude of the resonance peak are used to construct a multivariate high-order nonlinear system of equations. A global optimal function algorithm is used to determine the electron magnetic field, slowing factor, and electron transverse relaxation rate. The nuclear magnetic field is derived from the gyroscope compensation point, and the electron and nuclear polarizations are derived using the equivalent magnetic field formulas for alkali metal electron spins and inert gas nuclear spins. This method overcomes the shortcomings of existing parameter measurement methods and enables precise in-situ measurement of multiple parameters of a SERF atomic spin gyroscope using parameters such as the resonance peak without destroying the original state of the SERF atomic spin gyroscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of the implementation of the SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance of the present invention. Figure 1 The process includes step 1, applying an AC magnetic field B in the x direction. x , get B x Amplitude-frequency characteristic curve of AC magnetic field response; AC magnetic field B is applied in the y direction y , get B y The invention provides an amplitude-frequency characteristic curve of the AC magnetic field response; Step 2, respectively reading the resonance frequency and resonance amplitude of the alkali metal electron resonance peak in the x and y directions through the amplitude-frequency characteristic curve; Step 3, constructing a ternary high-order nonlinear equation system based on the relationship between the resonance frequency in the x direction, the resonance frequency in the y direction, and the ratio of the resonance peak amplitudes in the x and y directions; Step 4, solving the equation system by the global optimal function algorithm to obtain the electron magnetic field Be, the slowdown factor Q, and the electron transverse relaxation rate Step 5: Calculate the nuclear magnetic field Bn from the gyroscope compensation point Bc and the electron magnetic field Be, and calculate the electronic polarizability from the alkali metal electron spin equivalent magnetic field and the inert gas nuclear spin equivalent magnetic field. and nuclear polarizability DETAILED DESCRIPTION

[0028] Below is the attached figure ( Figure 1 ) and Examples illustrate the present invention.

[0029] Figure 1This is a flow chart of the SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance according to the present invention. Figure 1 As shown, the SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance includes the following steps: Step 1, applying an AC magnetic field B in the x direction x , get B x The first amplitude-frequency characteristic curve of the AC magnetic field response, with AC magnetic field B applied in the y direction y , get B y The second amplitude-frequency characteristic curve of the AC magnetic field response; Step 2, through the first amplitude-frequency characteristic curve, read the resonance frequency ωBx and the resonance amplitude FBx of the alkali metal electron resonance peak in the x direction, and through the second amplitude-frequency characteristic curve, read the resonance frequency ωBy and the resonance amplitude FBy of the alkali metal electron resonance peak in the y direction; Step 3, through ωBx, FBx, ωBy, FBy, construct a three-variable high-order nonlinear equation group; Step 4, solve the equation group by the global optimal function algorithm to obtain the electron magnetic field Be, the slowdown factor Q and the electron transverse relaxation rate Step 5: Calculate the nuclear magnetic field Bn from the gyroscope compensation point Bc and the electron magnetic field Be, and calculate the electronic polarizability from the alkali metal electron spin equivalent magnetic field and the inert gas nuclear spin equivalent magnetic field. and nuclear polarizability

[0030] The step 1 includes: heating the alkali metal gas chamber of the SERF atomic spin gyroscope to the operating temperature, and when the laser polarizes the atoms to a steady state, using the magnetic field cross-modulation compensation technology to compensate the magnetic field. At this time, the gyroscope operates at the "gyroscope compensation point Bc", satisfying Bc = -Be-Bn, fixing the SERF atomic spin gyroscope in a stationary state in the inertial space, applying an AC magnetic field with an amplitude of 0.3nT and a sine wave of different frequencies of 0.01Hz to 400Hz on the x-axis and y-axis respectively, obtaining the amplitude of the magnetic field response at different frequencies, drawing a frequency-peak-to-peak curve, and fitting it through the magnetic field transfer function to obtain B x 、B y Amplitude-frequency characteristic curve of the AC magnetic field response.

[0031] The three-variable high-order nonlinear equation system in step 3 is as follows:

[0032]

[0033] Where KFByx is the amplitude square ratio, which is expressed as the ratio of the square of the y-axis resonance peak amplitude to the square of the x-axis resonance peak amplitude, γ e =28nT / Hz is the electron gyromagnetic ratio.

[0034] The step 4 includes: setting the target function error as follows with the ternary high-order nonlinear equation set obtained from step 3 as a constraint condition:

[0035]

[0036] Wherein, is an electron resonance equation set,

[0037]

[0038] The global minimum value satisfying the target function is obtained through a global optimization function algorithm, and the result is an electron magnetic field Be, a slowing factor Q, and an electron transverse relaxation rate

[0039] The step 5 includes: Bn = -Bc-Be

[0040] The alkali metal electron spin equivalent magnetic field formula And the inert gas nucleus spin equivalent magnetic field formula Obtained:

[0041]

[0042]

[0043] Wherein, λ is an intermediate quantity of a simplified equation, κ0 is a Fermi contact constant, M e And M n are the magnetic intensities generated when the alkali metal electron spin and the inert gas atomic nucleus spin are completely polarized, and both are known values.

[0044] The SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance. The method first measures the amplitude-frequency characteristic curve of the SERF atomic spin gyroscope Bx, By AC magnetic field response, then finds the resonance frequency and resonance amplitude value corresponding to the alkali metal electron resonance peak in x and y directions respectively, and finally constructs an equation through the ratio of the resonance frequency and resonance amplitude value corresponding to the alkali metal electron resonance peak in x and y directions, and obtains the accurate values of the electron magnetic field, the slowing factor and the electron transverse relaxation rate through a global optimization function algorithm. The present application can realize in-situ accurate measurement of the electron magnetic field, the nucleus magnetic field, the electron polarization rate, the nucleus polarization rate, the slowing factor and the electron transverse relaxation rate of the SERF atomic spin gyroscope without changing the system state.

[0045] A SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance, comprising the following steps:

[0046] Step 1, obtain B x , B ythe amplitude-frequency characteristic curve of the alternating magnetic field response of B

[0047] Step 2, the resonance frequency and resonance amplitude of the alkali metal electron resonance peak in the x and y directions are read from the amplitude-frequency characteristic curves of the x and y directions respectively;

[0048] Step 3, a ternary nonlinear equation set is constructed from the relationship of the x-direction resonance frequency, the y-direction resonance frequency, and the ratio of the resonance peak amplitudes of the two directions;

[0049] Step 4, the equation set is solved by a global optimal function algorithm to obtain the electron magnetic field Be, the slowing factor Q, and the electron transverse relaxation rate

[0050] Step 5, Bn is obtained from the gyro compensation point Bc and the electron magnetic field Be, and the electron polarizability and the nuclear polarizability are obtained from the alkali metal electron spin equivalent magnetic field formula and the inert gas nucleus spin equivalent magnetic field formula

[0051] The step 1 comprises: heating the SERF atomic spin gyro alkali metal cell to the working temperature, when the laser polarizes the atoms to the steady state, compensating the magnetic field by using the magnetic field cross modulation compensation technology, at this time, the gyro works at the "gyro compensation point", satisfying Bc=-Be-Bn; fixing the SERF atomic spin gyro in the inertial space static state, respectively applying sinusoidal waves with different frequencies of 0.3nT in amplitude and 0.01Hz-400Hz in frequency on the x-axis and the y-axis, obtaining the amplitude of the magnetic field response under different frequencies, drawing the frequency-peak-to-peak value curve, and fitting by the magnetic field transfer function to obtain B x y The amplitude-frequency characteristic curve of the alternating magnetic field response of B

[0052] The step 2 comprises: reading the resonance frequency and resonance amplitude of the B x resonance peak from the amplitude-frequency characteristic curve of the x-axis alternating magnetic field amplitude-frequency response, which are ωBx and FBx respectively; and reading the resonance frequency and resonance amplitude of the B y resonance peak from the amplitude-frequency characteristic curve of the y-axis alternating magnetic field amplitude-frequency response, which are ωBy and FBy respectively.

[0053] The step 3 comprises: constructing a ternary high-order nonlinear equation set from ωBx, FBx, ωBy, and FBy obtained in step 2.

[0054] The step 4 comprises: taking the ternary high-order nonlinear equation set obtained in step 3 as a constraint condition, setting an objective function, and obtaining the global minimum value satisfying the objective function by a global optimal function algorithm, and the results are the electron magnetic field Be, the slowing factor Q, and the electron transverse relaxation rate ​​

[0055] The step 5 includes: calculating the nuclear magnetic field Bn by the "gyro compensation point" Bc obtained by step 2 and the electronic magnetic field Be obtained by step 4, calculating the electronic polarizability and the nuclear polarizability

[0056] The ωBx obtained by step 2 satisfies the equation:

[0057]

[0058] The FBx obtained by step 2 satisfies the equation:

[0059]

[0060] The ωBy obtained by step 2 satisfies the equation:

[0061]

[0062] The FBy obtained by step 2 satisfies the equation:

[0063]

[0064] Wherein, K is the photoelectric conversion coefficient, is the electronic polarizability, γ e = 28 nT / Hz is the electronic gyromagnetic ratio, Q is the slowing factor, Be is the electronic magnetic field, is the electronic transverse relaxation rate. ωBx, FBx, ωBy, FBy are all measured known values.

[0065] By

[0066]

[0067] A three-element high-order nonlinear equation set is formed. KFByx is the amplitude square ratio, which is expressed as the ratio of the square of the y-axis resonance peak amplitude to the square of the x-axis resonance peak amplitude.

[0068] Step 4, using the three-element high-order nonlinear equation set obtained by step 3 as a constraint condition, setting the objective function error as

[0069]

[0070] Wherein, is the electronic resonance equation set,

[0071]

[0072] By global optimization function algorithm, the global minimum value satisfying the objective function is obtained, and the result is the electronic magnetic field Be, the slowing factor Q, and the electron transverse relaxation rate

[0073] Step 5, by Bc obtained from step 2 and Be obtained from step 4, can be obtained by calculation:

[0074] Bn = -Bc-Be

[0075] By alkali metal electron spin equivalent magnetic field formula And inert gas nuclear spin equivalent magnetic field formula Can be obtained

[0076]

[0077]

[0078] Wherein, In order to simplify the intermediate quantity of equation, κ0 is Fermi contact constant, M e And M n Respectively, the alkali metal electron spin and the inert gas atomic nucleus spin completely polarized produce the magnetization intensity, both are known values.

[0079] The content not described in detail in the specification of the present application belongs to the prior art known to those skilled in the art. It is indicated here that the above description is helpful for those skilled in the art to understand the present application, but it is not limited to the protection scope of the present application. Any equivalent replacement, modification, improvement and / or deletion of the above description without departing from the essential content of the present application falls within the protection scope of the present application.

Claims

1. A SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance, characterized in that: The following steps are involved: Step 1: Apply an AC magnetic field B in the x direction x , get B x The first amplitude-frequency characteristic curve of the AC magnetic field response, with AC magnetic field B applied in the y direction y , get B y The second amplitude-frequency characteristic curve of the AC magnetic field response; Step 2: Read the resonance frequency ωBx and the resonance amplitude FBx of the alkali metal electron resonance peak in the x direction through the first amplitude-frequency characteristic curve, and read the resonance frequency ωBy and the resonance amplitude FBy of the alkali metal electron resonance peak in the y direction through the second amplitude-frequency characteristic curve; Step 3, construct a three-variable high-order nonlinear equation system through ωBx, FBx, ωBy, and FBy; Step 4: Solve the equations using the global optimal function algorithm to obtain the electron magnetic field Be, the slowing factor Q, and the electron transverse relaxation rate. Step 5: Calculate the nuclear magnetic field Bn from the gyroscope compensation point Bc and the electron magnetic field Be, and calculate the electronic polarizability from the alkali metal electron spin equivalent magnetic field and the inert gas nuclear spin equivalent magnetic field. and nuclear polarizability The three-variable high-order nonlinear equation system in step 3 is as follows: Where KFByx is the amplitude square ratio, which is expressed as the ratio of the square of the y-axis resonance peak amplitude to the square of the x-axis resonance peak amplitude, γ e =28nT / Hz is the electron gyromagnetic ratio.

2. The SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance according to claim 1, characterized in that: The step 1 includes: heating the alkali metal gas chamber of the SERF atomic spin gyroscope to the operating temperature, and when the laser polarizes the atoms to a steady state, using the magnetic field cross-modulation compensation technology to compensate the magnetic field. At this time, the gyroscope operates at the "gyroscope compensation point Bc", satisfying Bc = -Be-Bn, fixing the SERF atomic spin gyroscope in a stationary state in the inertial space, applying an AC magnetic field with an amplitude of 0.3nT and a sine wave of different frequencies of 0.01Hz to 400Hz on the x-axis and y-axis respectively, obtaining the amplitude of the magnetic field response at different frequencies, drawing a frequency-peak-to-peak curve, and fitting it through the magnetic field transfer function to obtain B x 、B y Amplitude-frequency characteristic curve of the AC magnetic field response.

3. The SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance according to claim 1, characterized in that: The step 4 includes: using the three-variable high-order nonlinear equations obtained in step 3 as constraints, setting the objective function error as follows: in, is the electronic resonance equations, Through the global optimal function algorithm, the global minimum value that satisfies the objective function is obtained, and the results are the electron magnetic field Be, the slowing factor Q, and the electron transverse relaxation rate.

4. The SERF gyroscope multi-parameter in-situ measurement method based on transverse magnetic field resonance according to claim 1, characterized in that: The step 5 includes: Bn=-Bc-Be Through the alkali metal electron spin equivalent magnetic field formula and the equivalent magnetic field formula of inert gas nuclear spin get: in, λ is the intermediate quantity of the simplified equation, κ0 is the Fermi contact constant, M e and M n are the magnetization intensities produced when the alkali metal electron spin and the noble gas nuclear spin are fully polarized, and both are known values.

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