Rapid self-adaptive taming method and system for atomic clock

Abstract

The invention discloses a rapid self-adaptive taming method and system for an atomic clock. According to the invention, the later time point in the locking time of the atomic clock and the access time of the external reference source is used as the calculation starting point of the data acquisition time, and the time from the power-on time to the preset time interval of the atomic clock is used as the calculation ending point of the data acquisition time; according to the method, the data acquisition time better matched with the current atomic clock can be dynamically calculated, and the purpose of determining the maximum data acquisition time within an effective time range is achieved, so that more phase data per second can be obtained; on the basis, the target frequency accuracy matched with the current atomic clock can be accurately calculated in a fitting mode through the least square method, and frequency calibration is conducted on the atomic clock according to the target frequency accuracy. According to the mode, the taming precision of the atomic clock is ensured, and meanwhile, the taming time can be shortened as much as possible, so that high-precision rapid taming of the atomic clock is possible.

Description

Technical Field

[0001] The present invention relates to the technical field of atomic clock taming, and in particular, to a method and system for rapid adaptive taming of an atomic clock. Background Art

[0002] The content of this part only provides background information related to the present invention, and it may not constitute prior art.

[0003] With the rapid development of fields such as airborne and missile-borne, the demand for high-precision frequency signals in detection and guidance systems is increasing day by day. High-precision frequency signals can provide higher resolution and accuracy, which are crucial for accurately detecting targets, identifying target characteristics, and precisely guiding weapons. In these applications, atomic clocks are often used as frequency-providing devices because they can provide relatively stable frequency outputs. However, the frequency accuracy of the atomic clock itself may not fully meet the requirements of high-precision frequency signals, so it needs to be tamed before use.

[0004] Currently, although there are some techniques for taming atomic clocks, these techniques may be insufficient in rapidly taming atomic clocks in a short time to provide high-precision frequencies. Therefore, it is necessary to study a technical solution that can rapidly tame atomic clocks in a short time to provide high-precision frequencies. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method and system for rapid adaptive taming of an atomic clock, which can shorten the taming time as much as possible while ensuring the taming accuracy.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] In a first aspect, the present invention discloses a method for rapid adaptive taming of an atomic clock, including:

[0008] Power on the atomic clock and output a first second pulse signal;

[0009] Connect to an external reference source and obtain a second second pulse signal;

[0010] Dynamically determine the data acquisition time, including:

[0011] Taking the later of the locking moment of the atomic clock and the access moment of the external reference source as the starting point;

[0012] Taking the power-on moment of the atomic clock as the reference, the moment after a preset time interval as the end point;

[0013] Calculating the time difference from the starting point to the end point as the data acquisition time;

[0014] Within the data acquisition time, perform the following steps:

[0015] Measure the phase difference between the first second pulse signal and the second second pulse signal per second;

[0016] Take the difference between the phase differences of adjacent seconds to obtain the phase deviation value of adjacent seconds, forming a phase deviation sequence;

[0017] Fit the phase deviation sequence to generate the target frequency accuracy;

[0018] Calibrate the frequency of the atomic clock according to the target frequency accuracy.

[0019] Optionally, the phase deviation sequence includes multiple time-phase deviation pairs, and each time-phase deviation pair includes a moment T n and its corresponding phase deviation value ΔΦ n ; where n is the nth second within the data acquisition time, and n≥2; the moment T n represents the moment corresponding to the nth second; the phase deviation value ΔΦ n is obtained by taking the difference between the phase difference of the nth second and the phase difference of the (n−1)th second;

[0020] Fitting the phase deviation sequence to generate the target frequency accuracy specifically includes:

[0021] Perform least squares linear fitting on all the time-phase deviation pairs, and use the slope of the fitting straight line as the target frequency accuracy.

[0022] Optionally, the process of dynamically determining the data acquisition time further includes:

[0023] Set a lower threshold for the acquisition time;

[0024] Among them, if the calculated data acquisition time is less than the lower threshold of the acquisition time, terminate the taming of the atomic clock.

[0025] Optionally, the lower threshold of the acquisition time is 30s.

[0026] Optionally, calibrating the frequency of the atomic clock according to the target frequency accuracy specifically includes:

[0027] Convert the target frequency accuracy into a frequency calibration parameter of the atomic clock and send it to the atomic clock through the serial port to adjust the frequency of the atomic clock.

[0028] Optionally, the process of accessing an external reference source and obtaining a second second pulse signal includes:

[0029] Identify the type of the external reference signal provided by the external reference source, where the external reference signal includes a second pulse signal, a frequency signal, or a B code;

[0030] Wherein, if the external reference signal is a second pulse signal, it is directly used as the second second pulse signal;

[0031] If the external reference signal is a frequency signal, frequency division processing is performed on the external reference signal to generate a second pulse signal;

[0032] If the external reference is a B code, the B code is parsed, and a second pulse signal is demodulated from the parsed B code.

[0033] In a second aspect, the present invention discloses an atomic clock fast adaptive taming system, including:

[0034] An atomic clock module, configured to output a first second pulse signal after power-on;

[0035] A reference source access module, configured to receive an input from an external reference source and obtain a second second pulse signal;

[0036] A dynamic acquisition time control module, connected to the atomic clock module and the reference source access module, for:

[0037] Taking the later of the locking moment of the atomic clock module and the access moment of the external reference source as the starting point;

[0038] Taking the power-on moment of the atomic clock as the reference, and the moment after a preset time interval as the end point;

[0039] Calculating the time difference from the starting point to the end point as the data acquisition time;

[0040] A signal processing module, connected to the atomic clock module and the reference source access module, for performing the following operations within the data acquisition time:

[0041] Measuring the phase difference between the first second pulse signal and the second second pulse signal second by second;

[0042] Taking the difference between the phase differences of adjacent seconds to generate a phase deviation value of adjacent seconds, forming a phase deviation sequence;

[0043] A fitting calculation module, connected to the signal processing module, for fitting the phase deviation sequence to obtain a target frequency accuracy;

[0044] A frequency calibration control module, connected to the fitting calculation module and the atomic clock module, for converting the target frequency accuracy into a frequency calibration parameter of the atomic clock module and sending it to the atomic clock module.

[0045] Optionally, the reference source access module includes:

[0046] A signal type detection unit for identifying the type of the external reference signal provided by the external reference source;

[0047] A signal conversion unit for performing the following operations according to the type of the external reference signal:

[0048] If the external reference signal is a second pulse signal, directly send the external reference signal to the signal processing module as the second second pulse signal;

[0049] If the external reference signal is a frequency signal, perform frequency division processing on the external reference signal to generate a second pulse signal and send it to the signal processing module as the second second pulse signal;

[0050] If the external reference signal is a B code, parse the B code and demodulate a second pulse signal from the parsed B code and send it to the signal processing module as the second second pulse signal.

[0051] Optionally, the dynamic acquisition time control module is further configured to: when the data acquisition time is less than the acquisition time lower limit threshold, terminate the taming process.

[0052] Optionally, the acquisition time lower limit threshold is 30 s.

[0053] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects:

[0054] In the present invention, by using the later time point between the locking moment of the atomic clock and the access moment of the external reference source as the starting point for calculating the data acquisition time, and using the moment after a predetermined time interval from when the atomic clock is powered on as the ending point for calculating the data acquisition time, it is possible to dynamically calculate a data acquisition time that is more matched with the current atomic clock, achieving the purpose of determining the maximum data acquisition time within an effective time range to obtain more phase data per second; on this basis, the target frequency accuracy matched with the current atomic clock can be more accurately fitted and calculated by the least squares method, and the atomic clock is frequency calibrated according to the target frequency accuracy. This method can shorten the taming time as much as possible while ensuring the taming accuracy of the atomic clock, thus providing the possibility for realizing high-precision and fast taming of the atomic clock. Description of the Drawings

[0055] Figure 1 It is a flowchart of the atomic clock fast adaptive taming method provided in Embodiment 1 of the present invention. Detailed Embodiment

[0056] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are 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 described embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0057] Compared with the embodiments shown in the drawings, the feasible embodiments within the scope of protection of the present invention may have fewer components, have other components not shown in the drawings, different components, differently arranged components, or differently connected components, etc. In addition, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0058] Embodiment 1

[0059] Embodiment 1 of the present invention discloses a method for rapid adaptive taming of an atomic clock, which is applied to an atomic clock, and in particular, can be the taming of a rubidium atomic clock.

[0060] Figure 1 is a flowchart of the method for rapid adaptive taming of an atomic clock disclosed in the embodiments of the present invention. As Figure 1 described, the taming method includes:

[0061] S10. Power on the atomic clock so that it starts to work and outputs a first second pulse signal. Among them, the atomic clock can be a rubidium atomic clock.

[0062] S20. Connect to an external reference source and obtain a second second pulse signal. Among them, the external reference source is suitable for providing an external reference signal for taming the atomic clock. For example, the external reference source can be a global positioning system (GPS) receiver, other high-precision atomic clocks (such as cesium atomic clocks or hydrogen atomic clocks), etc.

[0063] It should be noted that the external reference signal provided by the external reference source described in the embodiments of the present invention can be any signal with phase characteristics. For example, the external reference signal can be a second pulse signal, any frequency signal from 1M to 100M, or a B code.

[0064] In order to be able to smoothly use various types of external reference signals to tame the atomic clock, the taming method may further include: identifying the type of the external reference signal provided by the external reference source. Among them, if the external reference signal is a second pulse signal, it is directly used as the second second pulse signal; if the external reference signal is a frequency signal, the external reference signal is frequency-divided to generate a second pulse signal to be used as the second second pulse signal; if the external reference signal is a B code, the B code is first parsed, and then the parsed B code is demodulated to demodulate a second pulse signal from the parsed B code to be used as the second second pulse signal.

[0065] S30. Dynamically determine the data acquisition time, specifically including:

[0066] Taking the later of the locking time of the atomic clock and the access time of the external reference source as the starting point;

[0067] Taking the power-on time of the atomic clock as the reference, the time after a preset time interval is the end point;

[0068] Calculating the time difference from the starting point to the end point as the data acquisition time.

[0069] In the embodiments of the present invention, the locking time of the atomic clock refers to the time point when the atomic clock is powered on and reaches a stable working state. The access time of the external reference source refers to the time when the external reference source is accessed. Among them, "taking the power-on time of the atomic clock as the reference, the time after a preset time interval is the end point" means: taking the time after a preset time interval from when the atomic clock is powered on as the end point. The preset time interval is set manually. For example, the preset time interval can be 5 min, 6 min or other appropriate time intervals.

[0070] For example, assuming that the locking time of the atomic clock is time point T1, the access time of the external reference source is time point T2, and the time after a preset time interval from when the atomic clock is powered on is time point T3, then the data acquisition time Δt = T3 - T; in this formula, T is the later of T1 and T2.

[0071] Exemplarily, assume that the atomic clock is powered on at 9:00:00 Beijing time, and the preset time interval is 5 minutes. Then, starting from the power-on of the atomic clock, the moment after 5 minutes, that is, 9:05:00 Beijing time, is the calculation termination point of the data acquisition time. On this basis, assume that the locking moment of the atomic clock is 9:01:00 Beijing time, and the access moment of the external reference source is 9:01:10 Beijing time. Then, taking the access moment of the external reference source as the calculation starting point of the data acquisition time, calculate the specific data acquisition time, that is, the data acquisition time is 230 s; correspondingly, assume that the locking moment of the atomic clock is 9:01:30 Beijing time, and the access moment of the external reference source is 9:01:00 Beijing time. Then, taking the locking moment of the atomic clock as the calculation starting point of the data acquisition time, calculate the specific data acquisition time, that is, the data acquisition time is 210 s.

[0072] S40. On the basis of determining the data acquisition time, within the data acquisition time, the following steps can also be executed:

[0073] Measure the phase difference between the first second pulse signal and the second second pulse signal every second, that is, within the data acquisition time, measure the phase difference between the first second pulse signal and the second second pulse signal at each second;

[0074] Subtract the phase difference between the first second pulse signal and the second second pulse signal of adjacent seconds to obtain the phase deviation value of adjacent seconds, and form a phase deviation sequence; wherein, assume that the data acquisition time includes k seconds, then the phase deviation values of adjacent seconds include the phase deviation values between the 1st second and the 2nd second, between the 2nd second and the 3rd second,... between the k - 1th second and the kth second;

[0075] Fit the phase deviation sequence to generate the target frequency accuracy.

[0076] In the embodiment of the present invention, the phase deviation sequence includes multiple time-phase deviation pairs. Specifically, assume that the data acquisition time is Δt, then the number of time-phase deviation pairs is: Δt - 1. Exemplarily, assume that the data acquisition time is 230 s, then the number of time-phase deviation pairs is 229.

[0077] Wherein, each time-phase deviation pair includes a moment T n and its corresponding phase deviation value ΔΦ n .

[0078] Wherein, n is the nth second within the data acquisition time, and n ≥ 2, that is, there is no time-phase deviation pair for the 1st second within the data acquisition time range. The moment T nrepresents the moment corresponding to the nth second. For example, assuming that the access moment of the external reference source is 9:01:10 Beijing time, and the access moment of the external reference source is used as the starting point for calculating the data acquisition time, and the calculated data acquisition time is 230 s, then T2 represents the moment corresponding to the 2nd second, that is, 9:01:11 Beijing time. Among them, ΔΦ n is obtained by subtracting the phase difference between the first second pulse signal and the second second pulse signal at the nth second from the phase difference between the first second pulse signal and the second second pulse signal at the (n - 1)th second, that is, the phase deviation value corresponding to the moment T n . For example, the phase deviation value ΔΦ2 corresponding to the moment T2 = Φ2 - Φ1; where, Φ2 is the phase difference between the first second pulse signal and the second second pulse signal at the 2nd second; Φ1 is the phase difference between the first second pulse signal and the second second pulse signal at the 1st second.

[0079] For example, in combination with the foregoing, assuming that the access moment of the external reference source is 9:01:10 Beijing time, and the access moment of the external reference source is used as the starting point for calculating the data acquisition time, and the calculated data acquisition time is 230 s. Then the phase deviation sequence includes (T2, ΔΦ2), (T3, ΔΦ3)...(T 230 , ΔΦ 230 ) and a series of time-phase deviation pairs. Each time-phase deviation pair can be regarded as a data point in a rectangular coordinate system. Among them, T n in each time-phase deviation pair can be used as the abscissa, and ΔΦ n can be used as the ordinate. Among them, the time-phase deviation pair (T2, ΔΦ2) represents the phase deviation value of the atomic clock at the moment of 9:01:11 Beijing time, and the time-phase deviation pair (T3, ΔΦ3) represents the phase deviation value of the atomic clock at the moment of 9:01:12 Beijing time, and so on.

[0080] On this basis, based on the least squares algorithm, all the time-phase deviation pairs in the phase deviation sequence can be linearly fitted by the least squares method to obtain a linear fitting equation. It can be understood that the frequency accuracy of the atomic clock refers to the change of phase per unit time. Therefore, the slope of the fitting line in the linear fitting equation obtained by fitting a series of time-phase deviation pairs in the phase deviation sequence can be used as the target frequency accuracy.

[0081] It should be noted that the least squares method, as a mathematical optimization technique, can find the best function match for a set of data by minimizing the sum of the squares of the errors. Simply put, assuming there is a set of data, such as the phase deviation sequence described above, the least squares method can be used to fit a linear fitting equation, so that the sum of the squares of the perpendicular distances from all time-phase deviation pairs in the phase deviation sequence to the fitting line of this linear fitting equation is minimized.

[0082] Specifically, in the embodiments of the present invention, the process of using the least squares method to fit all time-phase deviation pairs in the phase deviation sequence to obtain the target frequency accuracy is as follows:

[0083] Define the sum of squared errors function S as:

[0084]

[0085] In the above formula: m is the number of time-phase deviation pairs in the phase deviation sequence; T i is the time corresponding to the i-th time-phase deviation pair; ΔΦ i is the phase deviation value corresponding to the time T i ; a0 is the intercept of the fitting line in the linear fitting equation; a1 is the slope of the fitting line in the linear fitting equation, that is, the target frequency accuracy to be determined in the embodiments of the present invention.

[0086] Determine the values of a0 and a1 by minimizing S. Specifically, by taking the partial derivatives of S with respect to a0 and a1 respectively, and setting the partial derivatives equal to 0, then:

[0087] For a0, there is:

[0088]

[0089] For a1, there is:

[0090]

[0091] By solving the system of equations composed of the above two equations, the calculation formulas for a0 and a1 can be obtained, which are:

[0092]

[0093] In the above two formulas:

[0094] On this basis, the slope a1 of the fitting line in the linear fitting equation, that is, the target frequency accuracy, can be calculated relatively accurately.

[0095] By using the least squares method to fit all time-phase deviation pairs in the phase deviation sequence to determine the target frequency accuracy, the accuracy of frequency accuracy estimation can be significantly improved. The least squares method can effectively suppress the interference of random noise and measurement errors by minimizing the sum of squared errors, thereby obtaining a fitting curve closer to the true frequency change law. This method can not only provide high-precision target frequency accuracy but also maintain good robustness in complex signal environments.

[0096] S50. Calibrate the frequency of the atomic clock according to the target frequency accuracy.

[0097] Among them, calibrating the frequency of the atomic clock according to the target frequency accuracy specifically includes: converting the target frequency accuracy into a frequency calibration parameter of the atomic clock and sending it to the atomic clock through the serial port protocol to adjust the frequency of the atomic clock, thereby completing the frequency calibration of the atomic clock. Among them, the technology of converting the frequency accuracy into a frequency calibration parameter of the atomic clock and sending it to the atomic clock through the serial port protocol belongs to the technology known in the prior art and will not be elaborated here.

[0098] It should be noted that when an atomic clock, especially a rubidium atomic clock, completes its own frequency calibration through a high-precision external reference source, the premise of frequency calibration accuracy is to accurately measure and calculate the frequency accuracy of the atomic clock, then convert the measured and calculated frequency accuracy into a frequency calibration parameter of the atomic clock, and send it to the atomic clock through the serial port for rapid frequency calibration.

[0099] The inventor of the present invention found that when using a known phase measurement chip, such as a TDC chip (time-to-digital converter chip), for phase acquisition, the measurement resolution of the chip depends on the specific chip model. Generally speaking, the measurement resolution of a TDC chip is about 200 ps. Coupled with the influence of adverse factors such as signal transmission interference, clock jitter, and jitter of the external reference source, the measurement resolution of the chip will deteriorate further, thereby affecting the accuracy of the phase measurement result. For example, assuming that the measurement resolution of the chip under the influence of adverse factors is 500 ps and the phase data of the atomic clock is collected once per second, the measurement error is 500 ps / 1 s = 5e-10; when the frequency accuracy of the atomic clock is higher than 5e-10 (that is, the actual phase deviation of the atomic clock is less than 5e-10), the error caused by the measurement resolution will be greater than the actual phase deviation of the atomic clock, thereby masking the actual phase change amount of the atomic clock.

[0100] The inventors of the present invention further found that, in order to reduce the phase measurement error caused by the measurement resolution of a phase measurement chip such as a TDC chip, an effective way is to measure more phase data per second (i.e., the phase data per second), so as to improve the reliability of the calculated frequency accuracy. Theoretically speaking, the more phase data per second, the more reliable the calculated frequency accuracy. To obtain more phase data per second, it is necessary to extend the time for collecting phase data per second, that is, the data acquisition time calculated in the embodiments of the present invention.

[0101] However, if the data acquisition time is blindly increased, the short-time and fast taming of the atomic clock cannot be achieved. Therefore, in combination with the above-disclosed content, it can be seen that the taming method proposed in the embodiments of the present invention calculates the starting point of the data acquisition time by using the later time point among the locking time of the atomic clock and the access time of the external reference source, and calculates the end point of the data acquisition time as the time point after a predetermined time interval from when the atomic clock is powered on. It can dynamically calculate the data acquisition time that better matches the current atomic clock, achieving the purpose of determining the maximum data acquisition time within an effective time range to obtain more phase data per second. On this basis, the least squares method can be used to more accurately fit and calculate the target frequency accuracy that matches the current atomic clock, and the atomic clock is frequency calibrated according to the target frequency accuracy. This method can ensure the taming accuracy of the atomic clock while shortening the taming time as much as possible, thus providing the possibility for realizing the high-precision and fast taming of the atomic clock.

[0102] In some embodiments, the process of dynamically determining the data acquisition time may further include: setting a lower threshold for the acquisition time. Among them, if the calculated data acquisition time is less than the lower threshold for the acquisition time, the taming of the atomic clock is terminated. It can be understood that by setting the lower threshold for the acquisition time, the minimum taming accuracy can be ensured when taming the atomic clock, thus guaranteeing the basic quality of the taming process.

[0103] For example, the lower threshold for the acquisition time may be 30s. If the calculated data acquisition time is less than 30s, the taming of the atomic clock is terminated.

[0104] Embodiment 2

[0105] Based on Embodiment 1, Embodiment 2 of the present invention discloses a fast adaptive taming system for an atomic clock, and this taming system is at least used to implement the fast adaptive taming method for an atomic clock described in Embodiment 1 above.

[0106] Specifically, this taming system may include an atomic clock module, a reference source access module, a dynamic acquisition time control module, a signal processing module, a fitting calculation module, and a frequency calibration control module.

[0107] The atomic clock module is used to output a first second pulse signal after power-on. For example, the atomic clock module may include a rubidium atomic clock.

[0108] The reference source access module is used to receive an external reference source input and obtain a second second pulse signal. Specifically, as can be seen from the content described in the foregoing Embodiment 1, the external reference signal provided based on the external reference source may be various types of signals such as a second pulse signal, a frequency signal, and a B code. Therefore, in order to be able to smoothly use various forms of external reference signals to tame the atomic clock, the reference source access module includes a signal type detection unit and a signal conversion unit. Among them, the signal type detection unit is used to identify the type of the external reference signal provided by the external reference source; the signal conversion unit is used to perform the following operations according to the type of the external reference signal:

[0109] If the external reference signal is a second pulse signal, directly send the external reference signal to the signal processing module as the second second pulse signal; if the external reference signal is a frequency signal, perform frequency division processing on the external reference signal to generate a second pulse signal and send it to the signal processing module as the second second pulse signal; if the external reference signal is a B code, parse the B code and demodulate the second pulse signal from the parsed B code and send it to the signal processing module as the second second pulse signal.

[0110] Among them, the above-mentioned signal type detection unit and signal conversion unit can be implemented by an FPGA chip. Specifically, the principle of the FPGA chip detecting and processing the external reference signal is roughly as follows:

[0111] For the second pulse signal, the FPGA chip can count the interval between the rising edges of two adjacent pulses of the external reference signal. If the interval between two adjacent pulses is within the range of 1s ± 0.1ms, the pulse width is greater than 1ms, and there are 3 consecutive pulse intervals and pulse widths that meet this condition, it is determined that the external reference signal is a second pulse signal.

[0112] For any frequency signal from 1M to 100M, the FPGA chip can count the number of pulses of the external reference signal within a fixed time, and then calculate the number of pulses per unit time, which is the frequency value of the external reference signal. The frequency value is considered a stable frequency signal if it is fixed within a certain time, and a second pulse signal can be obtained after frequency division.

[0113] For the B code, the FPGA chip can decode the external reference signal according to the GJB2991A-2008 standard, and a second pulse signal can be generated after meeting the pulse width and code element requirements.

[0114] The dynamic acquisition time control module is respectively communicatively connected to the atomic clock module and the reference source access module. The dynamic acquisition time control module is used to dynamically determine the data acquisition time described in Embodiment 1, that is, it is used for:

[0115] Starting from the later of the locking time of the atomic clock module and the access time of the external reference source; taking the power-on time of the atomic clock module as a reference, the time after a preset time interval is the end point; calculating the time difference from the start point to the end point as the data acquisition time.

[0116] Among them, the dynamic acquisition time control module may include a processor. The processor communicates with the atomic clock module via a serial port. Among them, the atomic clock is suitable for outputting a LOCK indication signal to the processor to prompt the processor of its own working state, so as to facilitate the processor to judge whether the atomic clock module is locked to determine the locking time of the atomic clock module. At the same time, the atomic clock module can output a 10MHz signal to the clock input pin of the processor as the working clock of the processor.

[0117] It can be understood that the atomic clock module outputs a LOCK indication signal and a 10MHz signal to the processor through serial communication, which is beneficial to ensuring that the processor can accurately obtain the working state of the atomic clock module and using the 10MHz signal provided by it as a stable clock source.

[0118] The signal processing module is communicatively connected to the atomic clock module and the reference source access module respectively. Among them, the signal processing module is used to perform the following operations within the data acquisition time:

[0119] Measure the phase difference between the first second pulse signal and the second second pulse signal every second;

[0120] Subtract the phase difference between the first second pulse signal and the second second pulse signal of adjacent seconds to generate a phase deviation value of adjacent seconds, forming a phase deviation sequence.

[0121] Among them, the signal processing module may include a TDC chip communicatively connected to the processor. The TDC chip can obtain the first second pulse signal and the second second pulse signal every second within the data acquisition time, and send the obtained first second pulse signal and second second pulse signal to the processor, so that the processor can calculate the phase difference between the first second pulse signal and the second second pulse signal per second within the data acquisition time based on the first second pulse signal and the second second pulse signal sent by the TDC chip, and subtract the phase difference between the first second pulse signal and the second second pulse signal of adjacent seconds to generate a phase deviation value of adjacent seconds to form a phase deviation sequence. Among them, the TDC chip and the processor can especially be communicatively connected via SPI, so that the processor can smoothly read and measure the phases of the first second pulse signal and the second second pulse signal through SPI and calculate the phase difference between the first second pulse signal and the second second pulse signal per second.

[0122] The fitting calculation module is connected to the signal processing module and is used to fit the phase deviation sequence. In particular, it performs a least-squares linear fit on all time-phase deviation pairs in the phase deviation sequence to obtain the target frequency accuracy. Herein, the target frequency accuracy is the slope of the fitting line of the linear fitting equation obtained through the least-squares linear fit.

[0123] Among them, the function of the fitting calculation module can be implemented by a processor.

[0124] The frequency calibration control module is communicatively connected to the fitting calculation module and the atomic clock module respectively. Among them, the frequency calibration control module is used to convert the target frequency accuracy into a frequency calibration parameter of the atomic clock module and send it to the atomic clock module to adjust the frequency of the atomic clock module, thereby completing the frequency calibration of the atomic clock module.

[0125] Among them, the function of the frequency calibration control module can also be implemented by a processor.

[0126] In some embodiments, the dynamic acquisition time control module is further used to: when the data acquisition time is less than the lower threshold of the acquisition time, terminate the taming process. Herein, the lower threshold of the acquisition time can be 30s.

[0127] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A fast adaptive taming method for an atomic clock, characterized in that Including: The atomic clock is powered on and outputs a first one-second pulse signal; An external reference source is accessed to obtain a second one-second pulse signal; Dynamically determine the data acquisition time, including: Taking the later of the locking moment of the atomic clock and the access moment of the external reference source as the starting point; Taking the power-on moment of the atomic clock as the reference, and the moment after a preset time interval as the end point; Calculating the time difference from the starting point to the end point as the data acquisition time; Within the data acquisition time, perform the following steps: Measure the phase difference between the first one-second pulse signal and the second one-second pulse signal every second; Subtract the phase differences of adjacent seconds to obtain the phase deviation values of adjacent seconds, forming a phase deviation sequence; Fit the phase deviation sequence to generate the target frequency accuracy; Calibrate the frequency of the atomic clock according to the target frequency accuracy.

2. The rapid adaptive taming method of an atomic clock according to claim 1, wherein The phase deviation sequence includes a plurality of time-phase deviation pairs, and each time-phase deviation pair includes a moment T n and its corresponding phase deviation value ΔΦ n ; where n is the nth second within the data acquisition time, and n ≥ 2; the moment T n represents the moment corresponding to the nth second; the phase deviation value ΔΦ n is obtained by subtracting the phase difference at the nth second from the phase difference at the (n - 1)th second; Fitting the phase deviation sequence to generate the target frequency accuracy specifically includes: Performing least squares linear fitting on all the time-phase deviation pairs, and taking the slope of the fitting straight line as the target frequency accuracy.

3. The rapid adaptive taming method of an atomic clock according to claim 2, characterized in that The process of dynamically determining the data acquisition time further includes: Setting a lower threshold for the acquisition time; Wherein, if the calculated data acquisition time is less than the lower threshold of the acquisition time, terminate the taming of the atomic clock.

4. The rapid adaptive taming method of an atomic clock according to claim 3, wherein The lower threshold of the acquisition time is 30 s.

5. The rapid adaptive taming method of an atomic clock according to claim 1, characterized in that Calibrating the frequency of the atomic clock according to the target frequency accuracy specifically includes: Converting the target frequency accuracy into a frequency calibration parameter of the atomic clock and sending it to the atomic clock through a serial port to adjust the frequency of the atomic clock.

6. The rapid adaptive taming method for an atomic clock according to claim 1, wherein The process of accessing the external reference source and obtaining the second one-second pulse signal includes: Identifying the type of the external reference signal provided by the external reference source, and the external reference signal includes a one-second pulse signal, a frequency signal or a B code; Wherein, if the external reference signal is a one-second pulse signal, directly use it as the second one-second pulse signal; If the external reference signal is a frequency signal, perform frequency division processing on the external reference signal to generate a one-second pulse signal; If the external reference is a B code, parse the B code and demodulate a one-second pulse signal from the parsed B code.

7. An atomic clock fast adaptive taming system, characterized in that Including: An atomic clock module, configured to output a first one-second pulse signal after being powered on; A reference source access module, configured to receive an input from an external reference source and obtain a second one-second pulse signal; A dynamic acquisition time control module, connected to the atomic clock module and the reference source access module, for: Taking the later of the locking moment of the atomic clock module and the access moment of the external reference source as the starting point; Taking the power-on moment of the atomic clock as the reference, and the moment after a preset time interval as the end point; Calculating the time difference from the starting point to the end point as the data acquisition time; A signal processing module, connected to the atomic clock module and the reference source access module, for performing the following operations within the data acquisition time: Measuring the phase difference between the first one-second pulse signal and the second one-second pulse signal every second; Subtracting the phase differences of adjacent seconds to generate the phase deviation values of adjacent seconds, forming a phase deviation sequence; The fitting calculation module, connected to the signal processing module, is configured to fit the phase deviation sequence to obtain the target frequency accuracy; The frequency calibration control module, connected to the fitting calculation module and the atomic clock module, is configured to convert the target frequency accuracy into the frequency calibration parameter of the atomic clock module and send it to the atomic clock module.

8. The rapid adaptive taming system of an atomic clock according to claim 7, characterized in that, The reference source access module includes: A signal type detection unit, configured to identify the type of the external reference signal provided by the external reference source; A signal conversion unit, configured to perform the following operations according to the type of the external reference signal: If the external reference signal is a second pulse signal, directly send the external reference signal to the signal processing module to be used as the second second pulse signal; If the external reference signal is a frequency signal, perform frequency division processing on the external reference signal to generate a second pulse signal and send it to the signal processing module to be used as the second second pulse signal; If the external reference signal is a B code, parse the B code and demodulate the second pulse signal from the parsed B code and send it to the signal processing module to be used as the second second pulse signal.

9. The atomic clock fast adaptive taming system according to claim 7, wherein The dynamic acquisition time control module is further configured to: when the data acquisition time is less than the acquisition time lower limit threshold, terminate the taming process.

10. The atomic clock fast adaptive taming system according to claim 9, characterized in that, The acquisition time lower limit threshold is 30 s.

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