Method for Measuring Absolute Gravity Value, Electronic Device

Abstract

Embodiments of the present application provide a method for measuring the absolute gravity value and an electronic device, relating to the technical field of absolute gravity value measurement. The method includes: determining a target interference fringe corresponding to the set pulse time interval in a target chirp rate range according to the corresponding relationship between the laser frequency chirp rate and the atomic ground state probability; obtaining target interference fringes corresponding to different set pulse time intervals, and determining a set of valley chirp rates corresponding to each target interference fringe, to obtain multiple sets of valley chirp rates; determining the chirp rate of the center extreme point of the interference fringe based on the valley chirp rates in the multiple sets of valley chirp rates, and calculating the absolute gravity value according to the chirp rate of the center extreme point of the interference fringe. The technical solution of the embodiments of the present application can improve the measurement efficiency of the absolute gravity value and has little impact on its measurement accuracy.

Description

Technical Field

[0001] This application relates to the technical field of absolute gravity value measurement. Specifically, it relates to a method for measuring absolute gravity value and an electronic device. Background Art

[0002] All objects on the earth's surface and in the nearby space are affected by gravity, and its direction is always vertically downward. Gravity measurement is to measure the acceleration of gravity, which plays an important role in the fields of geophysics, resource exploration, hydrology, volcanology, inertial navigation, and metrology. An atomic gravimeter is a high-precision absolute gravimeter based on an atomic interferometer. Compared with the traditional absolute gravimeter (FG5) based on a laser interferometer, the atomic gravimeter has no mechanical wear during operation and can continuously measure gravity for a long time. Its gravity measurement sensitivity and accuracy and other indicators can already be comparable to those of FG5.

[0003] Currently, the main methods for obtaining the absolute gravity value using an atomic gravimeter are as follows:

[0004] 1. The g value can be obtained through the Mach–Zehnder interference fringes of Doppler-insensitive transitions. Taking the lowest value point of a certain fringe as a reference, using different pulse time intervals T, after the same scanning process, the reference point will move accordingly. According to the shifted phase, the magnitude of the absolute gravity g can be deduced.

[0005] 2. The g value can be obtained through the Mach–Zehnder interference fringes of Doppler-sensitive transitions. In this case, when the frequency chirp of the laser completely compensates for the Doppler frequency shift generated by the atoms due to the action of gravity, by changing the pulse time interval T, a chirp rate point can always be found such that the total phase of the interferometer is always 0 at different Ts. Experimentally scanning the fringes corresponding to three different pulse time intervals T can determine the center position of the interference fringes, thereby obtaining an accurate g value.

[0006] The above methods still have the following problems: ① In Method 1, the effective wave vector k in the Doppler-insensitive transition process eff is five orders of magnitude worse than the effective wave vector in the Doppler-sensitive transition process. Correspondingly, its sensitivity to gravity is five orders of magnitude worse and cannot be used in high-precision atomic gravimeters; ② In Method 2, the frequency chirp range that needs to be scanned experimentally is generally very large. For each pulse time interval T, at least 6 cycles of interference fringe data are required to possibly find the center position of the interference fringes, which takes a long time, while when performing absolute gravity measurement in the wild, it is often necessary to quickly find the absolute gravity value g. Summary of the Invention

[0007] Embodiments of the present application provide a method for measuring the absolute gravity value, which can quickly find the accurate value of the absolute gravity value and save the time and cost required for measurement.

[0008] Other features and advantages of the present application will become apparent from the following detailed description, or be learned in part through the practice of the present application.

[0009] According to a first aspect of the embodiments of the present application, there is provided a method for measuring the absolute gravity value, which is applied to an atomic gravimeter and includes:

[0010] Based on different laser frequency chirp rates in a local chirp rate interval respectively, controlling a laser in the atomic gravimeter to emit a laser pulse sequence according to a set pulse time interval, and obtaining the atomic ground state probability at different laser frequency chirp rates, where the atomic ground state probability is the probability that an atom in the atomic gravimeter is in a set ground state;

[0011] According to the corresponding relationship between the laser frequency chirp rate and the atomic ground state probability, determining a target interference fringe in a target chirp rate interval corresponding to the set pulse time interval, where the target chirp rate interval includes the local chirp rate interval, and the target interference fringe has the characteristics of a cosine wave or a sine wave;

[0012] Obtaining target interference fringes corresponding to different set pulse time intervals, and determining a set of valley chirp rates corresponding to each target interference fringe, obtaining a plurality of sets of valley chirp rates, where the set of valley chirp rates includes a plurality of valley chirp rates;

[0013] Based on the valley chirp rates in the plurality of sets of valley chirp rates, determining the chirp rate of the central extreme point of the interference fringe, and calculating the absolute gravity value according to the chirp rate of the central extreme point of the interference fringe.

[0014] In some embodiments of the present application, based on the foregoing solution, the determining the target interference fringe in the target chirp rate interval corresponding to the set pulse time interval according to the corresponding relationship between the laser frequency chirp rate and the atomic ground state probability includes:

[0015] Fitting a local interference fringe in the local chirp rate interval according to the corresponding relationship between the laser frequency chirp rate and the atomic ground state probability;

[0016] Expanding the local interference fringe based on the characteristics of a cosine wave or a sine wave to obtain the target interference fringe in the overall chirp rate interval corresponding to the set pulse time interval.

[0017] In some embodiments of the present application, based on the foregoing solution, the fitting the local interference fringe in the local chirp rate interval according to the corresponding relationship between the laser frequency chirp rate and the atomic ground state probability includes:

[0018] Determine the fitting points in the interference fringe coordinate system according to the corresponding relationship between the laser frequency chirp rate and the atomic ground state probability;

[0019] Fit the fitting points by the least squares method to obtain the local interference fringes in the local chirp rate interval.

[0020] In some embodiments of the present application, based on the foregoing solution, the determining the set of valley chirp rates corresponding to each target interference fringe includes:

[0021] Determine the valley phases of each target interference fringe according to the cosine wave or sine wave characteristics of the target interference fringe;

[0022] Based on the valley phases of each target interference fringe, calculate all the valley chirp rates of each target interference fringe through formula (1);

[0023] P α = 1 / 2[1 + cos(ΔΦ)]; (1)

[0024] In formula (1), P α represents the valley chirp rate of the interference fringe, and Φ represents the valley phase;

[0025] Collect all the valley chirp rates of each target interference fringe to obtain the set of valley chirp rates corresponding to each target interference fringe.

[0026] In some embodiments of the present application, based on the foregoing solution, the determining the chirp rate of the central extreme point of the interference fringe based on the valley chirp rates in the multiple sets of valley chirp rates includes:

[0027] Select valley chirp rates with the number equal to the number of sets of valley chirp rates from the valley chirp rates in the multiple sets of valley chirp rates for combination to obtain multiple sets of valley chirp rates;

[0028] Calculate the standard deviation of the valley chirp rates in each set of valley chirp rates, and determine the set of valley chirp rates with the smallest standard deviation as the target set of valley chirp rates;

[0029] Based on the valley chirp rates in the target set of valley chirp rates, calculate the chirp rate of the central extreme point of the interference fringe.

[0030] In some embodiments of the present application, based on the foregoing solution, the selecting valley chirp rates with the number equal to the number of sets of valley chirp rates from the valley chirp rates in the multiple sets of valley chirp rates for combination to obtain multiple sets of valley chirp rates includes:

[0031] According to the preset combination times, randomly select a valley chirp rate from each set of valley chirp rates for combination to obtain multiple sets of valley chirp rates.

[0032] In some embodiments of the present application, based on the foregoing solution, selecting valley chirp rates with a quantity equal to the number of sets of valley chirp rates from the valley chirp rates of the multiple sets of valley chirp rates for combination to obtain multiple sets of valley chirp rates, including:

[0033] Sort the valley chirp rates in the multiple sets of valley chirp rates based on the magnitude of the valley chirp rates;

[0034] Combine any adjacent valley chirp rates with a quantity equal to the number of sets of valley chirp rates to obtain multiple sets of valley chirp rates.

[0035] In some embodiments of the present application, based on the foregoing solution, calculating the chirp rate of the central extreme point of the interference fringe based on the valley chirp rates of the target set of valley chirp rates, including:

[0036] Calculate the average value of the valley chirp rates of the target set of valley chirp rates as the chirp rate of the central extreme point of the interference fringe.

[0037] In some embodiments of the present application, based on the foregoing solution, calculating the absolute gravity value according to the chirp rate of the central extreme point of the interference fringe, including:

[0038] Obtain the effective wave vector of the laser;

[0039] Based on the effective wave vector of the laser and the chirp rate of the central extreme point of the interference fringe, calculate the absolute gravity value using formula (2);

[0040]

[0041] Among them, α represents the chirp rate of the central extreme point of the interference fringe, k eff represents the effective wave vector of the laser, and g represents the absolute gravity value.

[0042] According to the second aspect of the embodiments of the present application, there is provided a computer-readable storage medium, on which computer instructions are stored. When the computer instructions run on a computer, the computer is enabled to execute the method described in the first aspect.

[0043] According to the third aspect of the embodiments of the present application, there is provided an electronic device, including a processor and a memory;

[0044] The memory is used to store instructions;

[0045] The processor is configured to call the instructions in the memory, so that the electronic device executes the method described in the first aspect.

[0046] The technical solution of the present application utilizes the characteristic that the interference fringe is a cosine wave or a sine wave, expands the local interference fringe to obtain the target interference fringe, greatly reduces the calculation period of the interference fringe, and improves the efficiency of calculating the absolute gravity value; and while improving the efficiency, this technical solution does not significantly reduce the accuracy, and is very suitable for the rapid calculation of the absolute gravity value.

[0047] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts. In the drawings:

[0049] Figure 1 A schematic flowchart of a method for measuring an absolute gravity value according to an embodiment of the present application is shown;

[0050] Figure 2 A schematic diagram of an interference fringe provided according to an embodiment of the present application is shown;

[0051] Figure 3 A detailed flowchart of determining a target interference fringe in a target chirp rate range corresponding to the set pulse time interval according to the correspondence between the laser frequency chirp rate and the atomic ground state probability according to an embodiment of the present application is shown;

[0052] Figure 4 A detailed flowchart of determining a chirp rate of the central extreme point of the interference fringe based on the valley chirp rates in the plurality of valley chirp rate sets according to an embodiment of the present application is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0053] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the present application will be more complete and comprehensive, and will fully convey the concept of the example embodiments to those skilled in the art.

[0054] In addition, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of the embodiments of the present application. However, those skilled in the art will realize that the technical solutions of the present application may be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. may be employed. In other cases, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the present application.

[0055] The block diagrams shown in the drawings are only functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0056] The flowcharts shown in the drawings are only illustrative and do not necessarily include all the content and operations / steps, nor do they necessarily have to be executed in the described order. For example, some operations / steps may be decomposed, while some operations / steps may be combined or partially combined, so the actual execution order may change according to the actual situation.

[0057] It should be noted that: "a plurality" as mentioned herein refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0058] It should be noted that the terms "first", "second", etc. in the specification, claims, and above-mentioned drawings of the present application are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the objects so used may be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described.

[0059] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0060] The following will describe in detail some embodiments of the present application in conjunction with the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments may be combined with each other.

[0061] Referring to Figure 1 , a schematic flow chart of an absolute gravity value measurement method according to an embodiment of the present application is shown.

[0062] This embodiment provides an absolute gravity value measurement method, which is applied to an atomic gravimeter. The principle of this method is as follows:

[0063] The atomic gravimeter can be regarded as an atomic Mach-Zehnder interferometer. Through a π / 2-π-π / 2 pulse sequence with a pulse time interval of T, beam splitting, reflection, and beam combination of atoms are realized, and interference is formed.

[0064] In the atomic gravimeter, since the atoms are in free fall motion, the gravitational acceleration will continuously change the atomic velocity. In order to cancel the Doppler effect and keep the atoms in resonance with the three laser beams all the time, continuous frequency sweeping compensation of the laser is required, that is:

[0065] Δω(t) = ω0 + α(t - t0);

[0066] ω0 and t0 are the frequency and time of the first laser beam, and α is the chirp rate of the frequency change.

[0067] By scanning the chirp rate and simultaneously detecting the change in the population of the final-state atoms, interference fringes can be obtained:

[0068] P α = 1 / 2[1 + CoS(ΔΦ)];

[0069] ΔΦ represents the trough phase of the interference fringe.

[0070] When the frequency chirp of the laser can completely compensate the Doppler frequency shift:

[0071] ΔΦ total = k eff gT 2 -αT 2 = 0

[0072] k eff represents the effective wave number of the laser.

[0073] When α = keffg, the total phase no longer changes with T. At this chirp rate, different Ts can completely cancel out the Doppler frequency shift caused by gravity. On the interference fringes, it is manifested that the total phase of the interferometer with different Ts is equal to 0 at this chirp rate point. The chirp rate corresponding to this central fringe extreme point contains local gravity value information. Then, by scanning at least the fringes corresponding to three different Ts, the positions of the central extreme points of all interference fringes can be determined, thereby obtaining an accurate g value.

[0074] As Figure 1 shown, this method specifically includes steps S110 to S140.

[0075] Step S110: Based on different laser frequency chirp rates in a local chirp rate interval, control the laser in the atomic gravimeter to emit a laser pulse sequence at a set pulse time interval, and obtain the atomic ground state probability at different laser frequency chirp rates. The atomic ground state probability is the probability that the atoms in the atomic gravimeter are in a set ground state.

[0076] It should be noted that the basic starting point of the atomic interferometer based on atomic internal state interference is that light can be used to detect the motion state of atoms. Due to the Doppler effect, a change in the atomic motion speed will cause a change in the resonance frequency of the light interacting with it. Consider the interaction between a freely falling two-level atom in a gravitational field and a vertically propagating light field. Since the atom is accelerating, the frequency of the light must chirp at a certain rate of change to always maintain a resonant interaction with the atom. When the transition linewidth of the two-level atom is much smaller than the Doppler frequency shift during the falling process and the Rabi frequency of the interaction with the light field, the chirp rate is a very good physical quantity for measuring the gravitational acceleration value. A small change in the acceleration value will cause the light and the atom to not be strictly resonant, thereby affecting the mutual conversion of the two-level atomic numbers. By measuring the population of atoms in the excited state, a method for measuring the acceleration through the chirp rate is provided.

[0077] It can be understood that the laser frequency chirp rate described in this embodiment refers to the characteristic value of the change of the laser frequency with time. Specifically, it can refer to the rate of change of the laser frequency.

[0078] Step S120: According to the correspondence between the laser frequency chirp rate and the atomic ground state probability, determine the target interference fringes in the target chirp rate interval corresponding to the set pulse time interval. The target chirp rate interval includes the local chirp rate interval, and the target interference fringes have the characteristics of a cosine wave or a sine wave.

[0079] It can be understood that a cosine wave or a sine wave has periodicity. When the phase corresponding to a wave crest or a wave trough is known, the phases corresponding to all wave troughs can be quickly calculated based on its periodicity.

[0080] The correspondence between the laser frequency chirp rate and the atomic ground state probability means that in the same coordinate system, the laser frequency chirp rate and the atomic ground state probability can be used as the abscissa and the ordinate respectively. Then, after obtaining the corresponding atomic ground state probability and laser chirp rate, when irradiated onto the coordinate system, a corresponding target interference fringe can be obtained, as Figure 2 shown.

[0081] It should be noted that the target chirp rate interval refers to the range of chirp rates that need to be obtained in the prior art to obtain the target interference fringe, and the local chirp rate interval refers to the range of chirp rates that need to be obtained in the technical solution of this application.

[0082] The prior art obtains the target interference fringe by obtaining the chirp rates within the target chirp rate interval, while the technical solution of this application only needs to obtain the local chirp rate interval to obtain the target interference fringe. Compared with the prior art, the range of chirp rates obtained in this application is smaller, greatly improving the calculation efficiency.

[0083] In some feasible embodiments, determining the target interference fringe corresponding to the set pulse time interval under the target chirp rate interval according to the correspondence between the laser frequency chirp rate and the atomic ground state probability, as Figure 3 shown, specifically includes steps S121 to S122.

[0084] Step S121, fitting the local interference fringe within the local chirp rate interval according to the correspondence between the laser frequency chirp rate and the atomic ground state probability.

[0085] Step S122, expanding the local interference fringe based on the characteristics of a cosine wave or a sine wave to obtain the target interference fringe corresponding to the set pulse time interval under the overall chirp rate interval.

[0086] Exemplarily, for example, if the obtained local interference fringe only includes one wave crest, while the target interference fringe includes five wave crests, then according to the characteristics of the cosine wave or sine wave of the interference fringe, it is expanded on the local interference fringe until the local interference fringe has five wave crests.

[0087] In some feasible embodiments, fitting the local interference fringe within the local chirp rate interval according to the correspondence between the laser frequency chirp rate and the atomic ground state probability specifically includes steps S1211 to S1212.

[0088] Step S1211: Determine the fitting points in the interference fringe coordinate system according to the correspondence between the laser frequency chirp rate and the atomic ground state probability.

[0089] It should be noted that the interference fringe coordinate system mentioned in this embodiment refers to a coordinate system with the laser chirp rate as the abscissa and the atomic ground state probability as the ordinate.

[0090] Step S1212: Fit the fitting points by the least squares method to obtain the local interference fringes in the local chirp rate interval.

[0091] The least squares method (also known as the method of least squares) is a mathematical optimization technique. It finds the best function match for the data by minimizing the sum of the squares of the errors. Using the least squares method, the unknown data can be easily obtained, and the sum of the squares of the errors between the obtained data and the actual data is minimized. The least squares method can be used for curve fitting, and some other optimization problems can also be expressed by the least squares method by minimizing the energy or maximizing the entropy.

[0092] Continue to refer to Figure 1 , step S130: Obtain the target interference fringes corresponding to different set pulse time intervals, and determine the set of valley chirp rates corresponding to each target interference fringe, to obtain multiple sets of valley chirp rates, where the set of valley chirp rates includes multiple valley chirp rates.

[0093] Exemplarily, the interference fringe α obtained at the pulse time interval T1 T1 ; the interference fringe obtained at the pulse time interval T2 is α T2 ; the interference fringe obtained at the pulse time interval T3 is α T3 .

[0094] Then the interference fringe wave valley chirp rate corresponding to the interference fringe α T1 is and its set of valley chirp rates is The interference fringe wave valley chirp rate corresponding to the interference fringe α T2 is and its set of valley chirp rates is The interference fringe wave valley chirp rate corresponding to the interference fringe α T3 is and its set of valley chirp rates is

[0095] In some feasible embodiments, the determining the set of valley chirp rates corresponding to each target interference fringe specifically includes steps S131 to S133.

[0096] Step S131: Determine the valley phase of each target interference fringe according to the cosine wave or sine wave characteristics of the target interference fringe.

[0097] Step S132: Based on the wave - valley phases of each target interference fringe, calculate all the wave - valley chirp rates of each target interference fringe through formula (1).

[0098] P α =1 / 2[1 + cos(ΔΦ)]; (1)

[0099] In formula (1), P α represents the wave - valley chirp rate of the interference fringe, and Φ represents the wave - valley phase.

[0100] Step S133: Collect all the wave - valley chirp rates of each target interference fringe to obtain the wave - valley chirp rate set corresponding to each target interference fringe.

[0101] Continue to refer to Figure 1 , step S140: Based on the wave - valley chirp rates in the multiple wave - valley chirp rate sets, determine the chirp rate of the central extreme point of the interference fringe, and calculate the absolute gravity value according to the chirp rate of the central extreme point of the interference fringe.

[0102] In some feasible embodiments, the determining the chirp rate of the central extreme point of the interference fringe based on the wave - valley chirp rates in the multiple wave - valley chirp rate sets, as Figure 4 shown, specifically includes steps S141 to S143.

[0103] Step S141: Select a number of wave - valley chirp rates equal to the number of wave - valley chirp rate sets from the wave - valley chirp rates in the multiple wave - valley chirp rate sets for combination to obtain multiple wave - valley chirp rate groups.

[0104] Based on the foregoing example, a total of to three wave - valley chirp rate sets are obtained. Select three wave - valley chirp rates from these three wave - valley chirp rate sets for combination, that is, select three wave - valley chirp rates from these wave - valley chirp rates for combination to obtain wave - valley chirp rate groups.

[0105] Step S142: Calculate the standard deviation of the wave - valley chirp rates in each wave - valley chirp rate group, and determine the wave - valley chirp rate group with the smallest standard deviation as the target wave - valley chirp rate group.

[0106] Step S143: Based on the wave - valley chirp rates of the target wave - valley chirp rate group, calculate the chirp rate of the central extreme point of the interference fringe.

[0107] It should be noted that the reason for finding the chirp rate of the central extreme point of the interference fringe by calculating the standard deviation is as follows:

[0108] By changing different Ts to obtain different wave - valley chirp rates of interference fringes, when arranging these wave - valley chirp rates in ascending order, there are only three cases for any adjacent three wave - valley chirp rates: 1. Two wave - valley chirp rates come from the interference fringes of the same T, and the other wave - valley chirp rate comes from the interference fringes of another T; 2. All three wave - valley chirp rates come from the interference fringes of the same T; 3. The three wave - valley chirp rates come from the interference fringes obtained from different Ts. Obviously, in the first two cases, at least two wave - valley chirp rates correspond to wave - valley phases with a difference of 2π, and the difference between the two wave - valley chirp rates is not less than Then the standard deviation of these three wave - valley chirp rates must be greater than the standard deviation of the three wave - valley chirp rates near the extreme value point at the center of the interference fringe. In the third case, only the three wave - valley chirp rates near the extreme value point at the center of the interference fringe can have the lowest standard deviation value. Then, by calculating the standard deviation of any adjacent three wave - valley chirp rates and taking the average of the three wave - valley chirp rates at the minimum point as the chirp rate of the extreme value point at the center of the interference fringe.

[0109] In some feasible embodiments, selecting wave - valley chirp rates with a quantity equal to the number of wave - valley chirp rate sets from the wave - valley chirp rates of the multiple wave - valley chirp rate sets for combination to obtain multiple wave - valley chirp rate groups, specifically including step S1411.

[0110] Step S1411: Arbitrarily select one wave - valley chirp rate from each wave - valley chirp rate set according to a preset combination number to obtain multiple wave - valley chirp rate groups.

[0111] Exemplarily, based on the foregoing example, in Arbitrarily select one wave - valley chirp rate from these three wave - valley chirp rate sets. For example, select to form a wave - valley chirp rate group, and then select to form a wave - valley chirp rate group, and so on. 64 wave - valley chirp rate groups are obtained.

[0112] In another feasible embodiment, selecting wave - valley chirp rates with a quantity equal to the number of wave - valley chirp rate sets from the wave - valley chirp rates of the multiple wave - valley chirp rate sets for combination to obtain multiple wave - valley chirp rate groups, specifically including:

[0113] Based on the magnitudes of the wave - valley chirp rates, sort the wave - valley chirp rates in the multiple wave - valley chirp rate sets; combine any adjacent wave - valley chirp rates with a quantity equal to the number of wave - valley chirp rate sets to obtain multiple wave - valley chirp rate groups.

[0114] Exemplarily, based on the foregoing example, arrange Sort in ascending order, for example, the sorting order is Then combine the chirp rates of any three adjacent wave troughs, for example And so on, to obtain 10 groups of wave trough chirp rates.

[0115] It can be seen from this that the technical solution adopted in this embodiment results in fewer groups of wave trough chirp rates, making it easier to confirm the central extreme point of the interference fringes.

[0116] In some feasible embodiments, calculating the chirp rate of the central extreme point of the interference fringes based on the chirp rate of the target wave trough chirp rate group includes:

[0117] Calculate the average value of the chirp rates of the target wave trough chirp rate group as the chirp rate of the central extreme point of the interference fringes.

[0118] Exemplarily, based on the foregoing example, if is the group with the smallest standard deviation value, then take the average value of as the chirp rate of the central extreme point of the interference fringes.

[0119] In some feasible embodiments, calculating the absolute gravity value according to the chirp rate of the central extreme point of the interference fringes specifically includes steps S144 to S145.

[0120] Step S144, obtain the effective wave vector of the laser.

[0121] Step S145, based on the effective wave vector of the laser and the chirp rate of the central extreme point of the interference fringes, calculate the absolute gravity value using formula (2);

[0122]

[0123] where α represents the chirp rate of the central extreme point of the interference fringes, k eff represents the effective wave vector of the laser, and g represents the absolute gravity value.

[0124] As another aspect, the present application also provides a computer-readable storage medium, on which computer instructions are stored. When the computer instructions run on a computer, the computer is made to execute the method for measuring the absolute gravity value described in the above embodiments.

[0125] As another aspect, the present application also provides an electronic device, including a processor and a memory;

[0126] The memory is used to store instructions;

[0127] The processor is configured to call the instructions in the memory, so that the electronic device executes the method for measuring the absolute gravity value described in the foregoing embodiments.

[0128] It should be noted that the computer-readable medium shown in the embodiments of the present application may be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries computer-readable program code. Such a propagated data signal may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted by any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0129] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present application. Among them, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the above-mentioned module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram or flowchart, as well as the combination of blocks in the block diagram or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0130] The units described in the embodiments of the present application can be implemented in software or in hardware, and the described units can also be provided in a processor. Among them, the names of these units do not constitute a limitation to the unit itself in some cases.

[0131] It should be noted that although several modules or units of devices for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present application, the features and functions of the two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0132] From the description of the above embodiments, those skilled in the art can easily understand that the example embodiments described herein can be implemented by software or by a combination of software and necessary hardware. Therefore, the technical solutions according to the embodiments of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, a touch terminal, or a network device, etc.) to execute the method according to the embodiments of the present application.

[0133] Other embodiments of the present application will be readily contemplated by those skilled in the art after considering the specification and practicing the embodiments disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include known common general knowledge or conventional technical means in the technical field not disclosed in the present application. It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A method for measuring the absolute gravity value, applied to an atomic gravimeter, characterized in that, include: Based on different laser frequency chirp rates in a local chirp rate range, a laser in the atomic gravimeter is controlled to emit a laser pulse sequence according to a set pulse time interval, and the atomic ground state probability at different laser frequency chirp rates is obtained, where the atomic ground state probability is the probability that an atom in the atomic gravimeter is in a set ground state; Determining target interference fringes in a target chirp rate interval corresponding to the set pulse time interval based on a correspondence between the laser frequency chirp rate and the atomic ground state probability, wherein the target chirp rate interval includes the local chirp rate interval, and the target interference fringes have characteristics of a cosine wave or a sine wave; Obtaining target interference fringes corresponding to different set pulse time intervals, and determining a trough chirp rate set corresponding to each target interference fringes, to obtain a plurality of trough chirp rate sets, wherein the trough chirp rate set includes a plurality of trough chirp rates; Based on the trough chirp rates in the plurality of trough chirp rate sets, the chirp rate of the central extreme point of the interference fringe is determined, and the absolute gravity value is calculated according to the chirp rate of the central extreme point of the interference fringe.

2. The method according to claim 1, characterized in that The determining, based on the correspondence between the laser frequency chirp rate and the atomic ground state probability, target interference fringes corresponding to the set pulse time interval in the target chirp rate range includes: Fitting local interference fringes in the local chirp rate range according to the corresponding relationship between the laser frequency chirp rate and the atomic ground state probability; The local interference fringes are expanded based on the characteristics of the cosine wave or the sine wave to obtain target interference fringes in the overall chirp rate range corresponding to the set pulse time interval.

3. The method according to claim 2, wherein The fitting of local interference fringes in the local chirp rate range according to the corresponding relationship between the laser frequency chirp rate and the atomic ground state probability includes: Determining fitting points in an interference fringe coordinate system according to a corresponding relationship between the laser frequency chirp rate and the atomic ground state probability; The fitting points are fitted by the least square method to obtain local interference fringes in the local chirp rate range.

4. The method according to claim 1, wherein Determining a set of trough chirp rates corresponding to each target interference fringe includes: Determine the trough phase of each target interference fringe based on the cosine wave or sine wave characteristics of the target interference fringe; Based on the trough phase of each target interference fringe, all trough chirp rates of each target interference fringe are calculated by formula (1); P α = 1 / 2[1 + cos(ΔΦ)]; (1) In Equation (1), P α represents the wave valley chirp rate of the interference fringe, and Φ represents the wave valley phase; All trough chirp rates of each target interference fringe are collected to obtain a set of trough chirp rates corresponding to each target interference fringe.

5. The method according to claim 1, wherein The step of determining the chirp rate of the central extreme point of the interference fringe based on the trough chirp rates in the plurality of trough chirp rate sets comprises: Selecting trough chirp rates of the plurality of trough chirp rate sets, the number of which is equal to the number of trough chirp rate sets, and combining them to obtain a plurality of trough chirp rate groups; Calculating the standard deviation of the trough chirp rate in each trough chirp rate group, and determining the trough chirp rate group with the smallest standard deviation as the target trough chirp rate group; Based on the trough chirp rates of the target trough chirp rate group, the chirp rate of the central extreme point of the interference fringe is calculated.

6. The method according to claim 5, characterized in that, Selecting a number of valley chirp rates equal to the number of valley chirp rate sets from the valley chirp rates of the multiple valley chirp rate sets for combination to obtain multiple valley chirp rate groups, including: According to a preset number of combinations, arbitrarily select one valley chirp rate from each valley chirp rate set for combination to obtain multiple valley chirp rate groups.

7. The method according to claim 5, characterized in that, Selecting a number of valley chirp rates equal to the number of valley chirp rate sets from the valley chirp rates of the multiple valley chirp rate sets for combination to obtain multiple valley chirp rate groups, including: Sorting the valley chirp rates in the multiple valley chirp rate sets based on the magnitude of the valley chirp rates; Combining any adjacent valley chirp rates with a number equal to the number of valley chirp rate sets to obtain multiple valley chirp rate groups.

8. The method according to claim 5, characterized in that Calculating the chirp rate of the interference fringe center extreme point based on the valley chirp rates of the target valley chirp rate group, including: Calculating the average value of the valley chirp rates of the target valley chirp rate group as the chirp rate of the interference fringe center extreme point.

9. The method according to claim 1, wherein Calculating the absolute gravity value according to the chirp rate of the interference fringe center extreme point, including: Obtaining the effective wave vector of the laser; Based on the effective wave vector of the laser and the chirp rate of the interference fringe center extreme point, calculating the absolute gravity value using formula (2); Among them, α represents the chirp rate of the extreme value point at the center of the interference fringe, k eff represents the effective wave number of the laser, and g represents the absolute gravity value.

10. An electronic device, characterized in that, Including a processor and a memory; The memory is used to store instructions; The processor is used to call the instructions in the memory, so that the electronic device executes the method according to any one of claims 1-9.

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