Automatic optimization method and device for frequency stability of atomic clock and electronic equipment
The parameters of the CPT atomic clock are automatically adjusted through the particle swarm optimization algorithm, which solves the problem of time-consuming and labor-consuming traditional manual adjustment, and realizes automatic optimization of the atomic clock frequency stability, improving production efficiency and cost-effectiveness.
Patent Information
- Application Number
- CN202411941475.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-05-13
AI Technical Summary
Traditional CPT atomic clocks have shortcomings in frequency stability and accuracy. They are mainly due to the jitter and aging of parameters such as laser, temperature, and magnetic fields. Researchers need to manually adjust multiple parameters to optimize performance, which is time-consuming and labor-consuming.
The particle swarm optimization algorithm is used to automatically optimize the various parameters of the CPT atomic clock, and the parameters are adjusted by the upper computer (computer) to achieve automatic optimization of the atomic clock frequency stability.
It realizes automatic optimization of the stability of CPT atomic clock frequency, saves manpower and time, reduces costs, and is suitable for large-scale production.
Smart Images
Figure CN119987485A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of atomic clock frequency stability, and in particular to an atomic clock frequency stability automatic optimization method, device and electronic equipment. Background Art
[0002] Traditional coherent population trapping (CPT) refers to the phenomenon that when atoms in the ground state transition through different channels at the same time, the transition channels interfere with each other, causing the atoms to be trapped in the superposition state of the ground state and no longer transition. The coherent population trapping atomic clock uses this principle to obtain an error signal through the interaction between light and atoms to lock the crystal oscillator frequency. The CPT atomic clock mainly includes a laser source, an atomic gas chamber, a heating element, a magnetic field coil, an optical element, a control circuit and other parts.
[0003] Frequency stability and accuracy are two important indicators for evaluating the performance of atomic clocks. The short-term frequency stability of CPT atomic clocks is mainly reflected in the signal-to-noise ratio and linewidth of the CPT signal, which depends on the selection of parameters such as laser, temperature, magnetic field, atomic gas chamber, and is also related to the jitter changes of laser frequency, power, polarization, temperature control temperature, etc. The medium- and long-term frequency stability is mainly affected by changes in operating temperature, slow changes in laser characteristics, and performance changes caused by aging of the atomic gas chamber. In CPT atomic clocks, the optical frequency shift caused by changes in laser power, frequency, and polarization, the buffer gas frequency shift caused by temperature changes, and the magnetic field frequency shift caused by changes or inhomogeneities in the magnetic field are the main factors that cause the frequency change of CPT atomic clocks, which will deteriorate the two important indicators of frequency stability and accuracy of the atomic clock. Generally, a good temperature control circuit and a stable magnetic field current can reduce the changes in buffer gas frequency shift and magnetic field frequency shift to a certain extent.
[0004] The stability improvement of CPT atomic clocks depends on the selection of various parameters and the effective suppression of frequency shift changes. The adjustable parameters in the optimization process of CPT atomic clocks include laser temperature, laser current, laser power, gas chamber temperature, microwave power, and magnetic field size. When optimizing the performance of an atomic clock, its various parameters need to be continuously adjusted to achieve the optimal value. These experimental parameters usually rely on the experience of researchers and related theories for manual adjustment, which is time-consuming and labor-intensive, and it is not easy to obtain the optimal value. Summary of the invention
[0005] In order to solve the above technical problems, the present invention proposes a method and device for automatically optimizing the performance of a CPT atomic clock by adjusting parameters by a host computer, and optimizes various parameters of the CPT atomic clock by a particle swarm optimization algorithm to achieve automatic optimization of the output frequency stability of the CPT atomic clock.
[0006] In a first aspect, an embodiment of the present invention provides a method for automatically optimizing the frequency stability of an atomic clock, comprising:
[0007] Setting various parameters and value ranges that affect the frequency stability of the atomic clock;
[0008] Obtain the frequency of the current atomic clock and calculate its frequency stability, and use the frequency stability as the value of the fitness function of the particle swarm algorithm;
[0009] The particle swarm algorithm is used to determine a set of optimal parameters including the various parameters, so that the frequency stability satisfies a preset particle swarm algorithm termination condition.
[0010] In some embodiments, the setting of various parameters w and value ranges affecting the frequency stability of the atomic clock includes:
[0011] w=(x1, x2, x3..., wherein x1, x2, x3...represent various parameters that affect the frequency stability of the atomic clock respectively, and different values are taken within their value ranges to form multiple groups of parameters as a parameter particle group, and each group of parameters is taken as an individual in the particle group; according to the particle group, a group of optimal parameters corresponding to the atomic clock is determined.
[0012] In some embodiments, obtaining the frequency of the current atomic clock and calculating its frequency stability includes:
[0013] Enter a set of initialization parameter values as the particle group initialization position value Set the initial speed value Make the atomic clock work normally and output frequency, set sampling time τ, sampling period T, sampling number N;
[0014] Calculate the output frequency stability of the atomic clock, including:
[0015] Calculate the error y between the output frequency of the atomic clock and the standard reference frequency;
[0016] Calculate the variance of the error y
[0017]
[0018] Based on the variance σ 2 (N, T, τ), get the deviation, that is, the frequency stability
[0019]
[0020] In some embodiments, the use of the particle swarm algorithm to determine a set of optimal parameters including the various parameters so that the frequency stability satisfies a preset particle swarm algorithm termination condition includes:
[0021] Preset the termination condition of the particle swarm algorithm. If the termination condition of the particle swarm algorithm is met, the optimization calculation is terminated; otherwise, a new position value is given. and speed value And update the optimal value and optimal position value of the particle and the group, return to the step of obtaining the frequency of the current atomic clock and calculating its frequency stability, and repeat the cycle until the calculated frequency stability meets the preset particle swarm algorithm termination condition, and the corresponding current new position value is the optimal parameter.
[0022] In some embodiments, the new position value and speed value The calculation methods include:
[0023]
[0024]
[0025] Where ω is the weight factor, c1, c2 are acceleration factors, which are normal numbers, r1, r2 are random numbers uniformly distributed in [0, 1], is the optimal position experienced by the particle when it moves in the search space, is the global optimal position.
[0026] In some embodiments, the atomic clock is a CPT atomic clock, and the parameters include:
[0027] The laser temperature, gas chamber temperature, microwave power, magnetic field size, PID value of the feedback system for locking the laser and VCO frequency, PID value of the temperature control feedback system, and control value of the phase-locked loop frequency division number of the CPT atomic clock.
[0028] In some embodiments, the preset particle swarm algorithm termination condition includes a preset frequency stability threshold, or a set number of cycles, or the calculation result converges, that is, the result no longer improves.
[0029] In a second aspect, an embodiment of the present invention provides an automatic optimization device for atomic clock frequency stability, which is used to implement an automatic optimization method for atomic clock frequency stability described in the first aspect, including:
[0030] A parameter setting module, used to set various parameters and value ranges that affect the frequency stability of the atomic clock;
[0031] A frequency stability acquisition module is used to acquire the frequency of the current atomic clock and calculate its frequency stability, and use the frequency stability as the value of the fitness function of the particle swarm algorithm;
[0032] The particle swarm algorithm and judgment module is used to use the particle swarm algorithm to determine a set of optimal parameters including the various parameters so that the frequency stability satisfies the preset particle swarm algorithm termination condition.
[0033] In a third aspect, an embodiment of the present invention provides an electronic device, including:
[0034] at least one memory for storing program instructions;
[0035] At least one processor is used to call the program instructions stored in the memory, and execute the steps of the method for automatically optimizing the frequency stability of an atomic clock described in the first aspect according to the obtained program instructions.
[0036] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of a method for automatically optimizing the frequency stability of an atomic clock as described in the first aspect.
[0037] The technical solution provided by the embodiments of the present invention brings at least the following beneficial effects:
[0038] The automatic optimization method for the frequency stability of an atomic clock of the present invention sets various parameters and value ranges that affect the frequency stability of the atomic clock, and uses a particle swarm algorithm to automatically optimize the stability of a CPT atomic clock by adjusting the parameters through a host computer (computer), thereby solving the problem of time-consuming and labor-intensive manual optimization of the performance of a CPT atomic clock, saving manpower, reducing costs, and meeting the needs of mass production of CPT atomic clocks.
[0039] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0040] Figure 1 Schematic diagram of the overall process of the method of this embodiment;
[0041] Figure 2 4 is a structural block diagram of the device of this embodiment.
[0042] In the figure, 1- parameter setting module, including computer memory; 2- frequency stability acquisition module; 3- particle swarm algorithm and judgment module, 4- computer (host computer). DETAILED DESCRIPTION
[0043] The embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.
[0044] Embodiment 1:
[0045] This embodiment provides a method for automatically optimizing the frequency stability of an atomic clock. Figure 1 Schematic diagram of the overall process. The optimization goal of the particle swarm optimization algorithm is to find a set of parameters within the setting range of the CPT atomic clock parameters to optimize the output frequency stability of the CPT atomic clock. The optimal frequency stability is less than or equal to the preset frequency stability threshold.
[0046] Specifically include:
[0047] Step 1: Determine the particle number M of the particle swarm and the value range of each parameter; determine the convergence basis or termination condition. In this embodiment, the convergence basis or termination condition is that the frequency stability meets the preset frequency stability threshold requirement.
[0048] The atomic clock of this embodiment is a CPT atomic clock. The various parameters refer to the laser temperature, gas chamber temperature, microwave power, magnetic field size, PID value of the feedback system for locking the laser and VCO frequency, PID value of the temperature control feedback system, control value of the phase-locked loop frequency division number, etc. of the CPT atomic clock. These parameters can be controlled by the host computer (see Figure 2 The parameters w = (x1, x2, x3...), where x1, x2, x3... respectively represent the parameters that affect the frequency stability of the atomic clock: laser temperature, gas chamber temperature, microwave power..., take different values within the value range, and arbitrarily combine them into multiple groups of parameters as a parameter particle group, and take each group of parameters as an individual in the particle group;
[0049] Step 2: Input a set of initialization parameter values to the CPT atomic clock as the particle swarm initialization position value Set the initial speed value Make the CPT atomic clock work normally and output frequency signals.
[0050] Step 3: Measure the output frequency of the current CPT atomic clock and calculate the stability.
[0051] The stability of the CPT atomic clock is a function of the laser temperature, gas chamber temperature, microwave power, magnetic field size, PID value of the feedback system for locking the laser and VCO frequency, PID value of the temperature control feedback system, and control value of the phase-locked loop frequency division number of the CPT atomic clock. The stability calculation result of the CPT atomic clock is used as the value of the fitness function.
[0052] Measuring the output frequency of the atomic clock specifically includes:
[0053] Set the sampling time τ, sampling period T, and sampling number N.
[0054] Calculate the output frequency stability of the atomic clock, including:
[0055] Calculate the error y between the output frequency of the atomic clock and the standard reference frequency (see Figure 2 The stability can be calculated by using the medium frequency comparator, but is not limited to the Allan variance and Hadamard variance.
[0056] Calculate the variance of the error y
[0057]
[0058] Based on the variance σ 2 (N, T, τ), get the deviation, that is, the frequency stability
[0059]
[0060] Step 4: Determine the convergence basis or termination condition. If the particle swarm algorithm termination condition is met, terminate the optimization calculation. If not, give a new position value. and speed value And update the optimal value and optimal position value of the particle and the group, and return to step three. If satisfied, output the current position value and terminate the optimization program. Convergence basis or termination condition, that is, the preset particle swarm algorithm termination condition includes a preset frequency stability threshold, or a set number of cycles, or the calculation result converges, that is, the result no longer improves, one of the situations. In this embodiment, the particle swarm algorithm termination condition is that the frequency stability meets the preset frequency stability threshold requirement, specifically, the frequency stability is less than or equal to the preset frequency stability threshold, and the calculated frequency stability is compared with the preset frequency stability threshold.
[0061] The calculation method of the new position value and speed value is:
[0062]
[0063] Where ω is the weight factor, c1, c2 are acceleration factors which are positive numbers, r1, r2 are random numbers uniformly distributed in [0,1], is the optimal position experienced by the particle when it moves in the search space, is the global optimal position.
[0064] Embodiment 2
[0065] This embodiment provides an automatic optimization device for atomic clock frequency stability, see Figure 2 , perform optimization calculations through the host computer (computer) and use the serial communication function to read and write the parameters of the CPT atomic clock. Use the serial port function and LabVIEW program to complete the acquisition and control functions of the CPT atomic clock parameters, and input a set of initialization parameter values as the particle group initialization position value Set the initial speed value Make the atomic clock work normally and output frequency, process the collected atomic clock output frequency through Matlab program, and judge whether it meets the preset particle swarm algorithm termination condition. If so, end the optimization calculation. If not, use Matlab to perform particle swarm algorithm to calculate the next set of parameter combinations, and then use the serial port function of LabVIEW to send parameter modification instructions to the CPT atomic clock, and repeat the above steps until the termination condition is met.
[0066] A method for realizing automatic optimization of atomic clock frequency stability, the automatic optimization device for atomic clock frequency stability comprises:
[0067] A parameter setting module, including a computer memory, is used to set various parameters and value ranges that affect the frequency stability of the atomic clock;
[0068] The module for obtaining frequency stability includes a LabVIEW program to complete the acquisition and control functions of the CPT atomic clock parameters, and also includes a frequency comparator to calculate the error y between the output frequency of the atomic clock and the standard reference frequency. In short, it is used to obtain the frequency of the current atomic clock and calculate its frequency stability, and the frequency stability is used as the value of the fitness function of the particle swarm algorithm;
[0069] The particle swarm algorithm and judgment module, including the particle swarm algorithm in the Matlab program, is used to use the particle swarm algorithm to determine a set of optimal parameters including the various parameters so that the frequency stability meets the preset frequency stability threshold requirement.
[0070] Embodiment 3
[0071] Provided is an electronic device comprising: a processor; a memory for storing processor executable instructions; wherein the processor implements the steps of the above-mentioned atomic clock frequency stability automatic optimization method by running the executable instructions.
[0072] Embodiment 4
[0073] A computer-readable storage medium is provided, on which computer instructions are stored. When the instructions are executed by a processor, the steps of the above-mentioned method for automatically optimizing the frequency stability of an atomic clock are implemented.
Claims
1. A method for automatically optimizing the frequency stability of an atomic clock, characterized in that: include: Setting various parameters and value ranges that affect the frequency stability of the atomic clock; Obtain the frequency of the current atomic clock and calculate its frequency stability, and use the frequency stability as the value of the fitness function of the particle swarm algorithm; The particle swarm algorithm is used to determine a set of optimal parameters including the various parameters, so that the frequency stability satisfies a preset particle swarm algorithm termination condition.
2. The method for automatically optimizing the frequency stability of an atomic clock according to claim 1, characterized in that: The setting of various parameters w and value ranges affecting the frequency stability of the atomic clock includes: w=(x1, x2, x3..., wherein x1, x2, x3...represent various parameters that affect the frequency stability of the atomic clock respectively, and different values are taken within their value ranges to form multiple groups of parameters as a parameter particle group, and each group of parameters is taken as an individual in the particle group; according to the particle group, a group of optimal parameters corresponding to the atomic clock is determined.
3. The method for automatically optimizing the frequency stability of an atomic clock according to claim 2, characterized in that: The obtaining the frequency of the current atomic clock and calculating its frequency stability includes: Enter a set of initialization parameter values as the particle group initialization position value Set the initial speed value Make the atomic clock work normally and output frequency, set sampling time τ, sampling period T, sampling number N; Calculate the output frequency stability of the atomic clock, including: Calculate the error y between the output frequency of the atomic clock and the standard reference frequency; Calculate the variance of the error y Based on the variance σ 2 (N, T, τ), get the deviation, that is, the frequency stability 4. The method for automatically optimizing the frequency stability of an atomic clock according to claim 3, characterized in that: The using the particle swarm algorithm to determine a set of optimal parameters including the various parameters so that the frequency stability satisfies a preset particle swarm algorithm termination condition includes: Preset the termination condition of the particle swarm algorithm. If the termination condition of the particle swarm algorithm is met, the optimization calculation is terminated; otherwise, a new position value is given. and speed value And update the optimal value and optimal position value of the particle and the group, return to the step of obtaining the frequency of the current atomic clock and calculating its frequency stability, and repeat the cycle until the calculated frequency stability meets the preset particle swarm algorithm termination condition, and the corresponding current new position value is the optimal parameter.
5. The method for automatically optimizing the frequency stability of an atomic clock according to claim 4, characterized in that: The new position value and speed value The calculation methods include: Where ω is the weight factor, c1, c2 are acceleration factors which are positive numbers, r1, r2 are random numbers uniformly distributed in [0,1], is the optimal position experienced by the particle when it moves in the search space, is the global optimal position.
6. The method for automatically optimizing the frequency stability of an atomic clock according to any one of claims 1 to 5, characterized in that: The atomic clock is a CPT atomic clock, and its parameters include: The laser temperature, gas chamber temperature, microwave power, magnetic field size, PID value of the feedback system for locking the laser and VCO frequency, PID value of the temperature control feedback system, and control value of the phase-locked loop frequency division number of the CPT atomic clock.
7. The method for automatically optimizing the frequency stability of an atomic clock according to any one of claims 1 to 6, characterized in that: The preset particle swarm algorithm termination condition includes a preset frequency stability threshold, or a set number of cycles, or the calculation result converges, that is, the result no longer improves.
8. An automatic optimization device for atomic clock frequency stability, used to implement the method according to any one of claims 1 to 7, characterized in that: include: A parameter setting module, used to set various parameters and value ranges that affect the frequency stability of the atomic clock; A frequency stability acquisition module is used to acquire the frequency of the current atomic clock and calculate its frequency stability, and the frequency stability is used as the value of the fitness function of the particle swarm algorithm; The particle swarm algorithm and judgment module is used to use the particle swarm algorithm to determine a set of optimal parameters including the various parameters so that the frequency stability satisfies the preset particle swarm algorithm termination condition.
9. An electronic device, characterized in that: include: at least one memory for storing program instructions; At least one processor is used to call the program instructions stored in the memory, and execute the steps of the method described in any one of claims 1 to 7 according to the obtained program instructions.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of any method described in claims 1 to 7 are implemented.