651results about "Apparatus using atomic clocks" patented technology

The invention relates to the technical field of atomic clock control, and discloses a punctuality type atomic clock control method based on a microwave frequency band. The method comprises the following steps: firstly, acquiring microwave frequency band signal data and atomic state data, and constructing a time calculation model in combination with historical operation data to output a theoretical time value; performing multi-dimensional difference analysis on the theoretical time value and the actual measurement time value to generate a time difference coefficient matrix; inputting the matrix into a spatial propagation analysis network, and combining atomic clock component parameters and environmental parameters to generate a time anomaly probability distribution diagram; and finally, configuring microwave control parameters according to the distribution diagram, including starting a high-frequency monitoring mode for a high-probability abnormal region and applying a disturbance test to adjacent frequency bands. According to the method, through multi-dimensional data modeling, difference analysis and dynamic parameter configuration, the accuracy and adaptability of atomic clock control are improved, and the operation stability of the atomic clock in a complex environment can be enhanced.

According to the hydrogen clock error forecasting method, system and device based on the improved recurrent neural network and the storage medium, the memory characteristic of the recurrent neural network is used for representing the time relation, so that hydrogen clock error forecasting is carried out, and the accuracy of hydrogen clock error forecasting is improved. The method comprises the following steps: acquiring original clock error data of a hydrogen clock, and preprocessing the original clock error data to obtain preprocessed clock error data; constructing a hybrid recurrent neural network model, and initializing the hybrid recurrent neural network model; dividing the preprocessed clock error data into a training set, a verification set and a test set; based on the training set, the verification set and the test set, using an RAdam optimizer and MAPE as loss functions, and optimizing the hybrid recurrent neural network model until a preset precision is reached; and preprocessing the clock error data of the to-be-predicted time period, and inputting the preprocessed clock error data of the to-be-predicted time period into the optimized hybrid recurrent neural network model to obtain a predicted clock error value.

The invention discloses a high-reliability precise time service device, and particularly relates to the field of precise time service, and the device comprises a GNSS antenna, a Beidou satellite receiver, a main control module, a rubidium atomic frequency standard module, a frequency distribution module, a time code generation module, a network time service module, a display control module and a power module. Standard time signals are obtained through the Beidou satellite receiver, time calibration and taming are carried out through the rubidium atomic frequency standard module, and it is ensured that the output time signals and standard time are kept synchronous; the frequency distribution module distributes and amplifies a 10MHz standard frequency signal output by the rubidium clock and then divides the 10MHz standard frequency signal into multiple paths for output; the time code generation module completes 1pps and B code signals; the network time service module provides standard time information generated by the equipment to a computer with a time service requirement in a network by using an NTP standard network time service protocol; and the power supply module provides conversion from 220V to direct current through AC / DC conversion, provides power supply for each functional module and controls the power-on sequence.

The invention relates to an all-welded Ramsey microwave resonant cavity for a cold atom fountain clock, the all-welded Ramsey microwave resonant cavity comprises a Ramsey resonant cavity, a flying area waveguide, a cut-off waveguide and a microwave feed-in system, the flying area waveguide is arranged above the Ramsey resonant cavity, and a non-closed atom free flight channel is formed above the flying area waveguide; the flying area waveguide is connected with the cut-off waveguide through welding; the cut-off waveguide is integrally connected with the Ramsey resonant cavity; the microwave feed-in system is connected with the Ramsey resonant cavity through welding. According to the invention, a full-cavity integrated structure is realized through an integrated welding process, the hidden danger of microwave leakage is thoroughly eliminated, repeated debugging is not needed after welding is completed, the tuning period of the resonant cavity is shortened, and the resonant cavity is especially suitable for a low-temperature working environment scene. Meanwhile, through a non-closed atom free flight channel, a vacuum system can conveniently keep a high vacuum state in a flight area, so that the loss of cold atom cohesion is reduced, and an atom signal is relatively large.

In a general aspect, a quantum spectrum sensing system is presented. In some implementations, a quantum spectrum sensing system includes a laser system, a vapor cell sensor, and an optical detector. The laser system includes first and second lasers configured to generate a first and second laser signals. The laser system also includes first and second comb generators configured to produce first and second frequency comb signals based on the first and second laser signals, respectively. The laser system includes a frequency separator that can select frequency components of the second frequency comb signal and a frequency shifter that can shift the selected frequency components toward Rydberg states of a vapor. The vapor cell sensor can receive input optical signals from the laser system and produce output optical signals based on interactions of the vapor with the input optical signals. The optical detector can detect the output optical signals.

The invention relates to the technical field of atomic frequency standards, in particular to a miniaturized atomic beam clock physical system and a clock generation method. The atomic beam clock physical system comprises an alkali metal atom emission cavity, an alkali metal raw material block, a microcapillary array, a drift cavity, a multi-layer silicon substrate, a laser, an optical fiber type phase modulator, a beam splitter prism, a plurality of reflectors and a signal detector. Compared with a traditional coherent population detection mode based on a bubble chamber, the chip-scale atomic clock has narrower fluorescence spectrum width and higher long-term frequency stability, meanwhile has the chip-scale capability, and has higher competitiveness compared with an existing chip-scale atomic clock based on an air chamber structure.

The invention provides a device and a method for generating a Lammer-type hot atomic beam light clock based on periodic pulses. The device comprises a pulse laser, a laser frequency stabilization system, an optical switch, a Laammer type hot atom chamber and a laser detection feedback system. Wherein the pulse laser is used for emitting first laser, and the pulse time is nanosecond magnitude. The laser frequency stabilization system is used for carrying out pre-frequency stabilization on the first laser to obtain second laser, and the second laser is conveyed to the Laammer type hot atom chamber through the optical switch; the switching period of the optical switch is set to be microsecond magnitude; the lamplug type hot atom chamber is used for outputting a lamplug type hot first atom beam; and the laser detection feedback system is used for detecting the first atomic beam, feeding back and controlling the pulse laser, locking the frequency of the pulse laser on a transition spectral line of atoms, and obtaining a hot atomic beam light clock. According to the invention, the interaction time of laser and atoms can be controlled, and the utilization rate of the atoms of the Lammer-type hot atomic beam light clock can be improved.

The invention discloses a light source generation system and method for a CPT atomic clock, and the system comprises a high-precision voltage-controlled constant current source, a low-phase-noise microwave source, a bias device, a temperature control circuit, a vertical-cavity surface-emitting laser, a linear polarizer, a 1 / 4 slide, and a microcontroller, and the high-precision voltage-controlled constant current source and the low-phase-noise microwave source are connected with the bias device. The bias device and the temperature control circuit are connected with the vertical cavity surface emitting laser, the linear polaroid and the 1 / 4 slide are arranged at the center of a light path emitted by the vertical cavity surface emitting laser, and the microcontroller controls the high-precision voltage-controlled constant current source, the low-phase-noise microwave source and the temperature control circuit. The system has the advantages of being simple in structure, small in size, suitable for different alkali metal atomic clocks and the like, meanwhile, the microwave source is high in frequency resolution, low in phase noise, adjustable in output power and suitable for a high-performance miniaturized CPT atomic clock.

The present application relates to a method, device, storage medium and terminal for optimizing the drift rate of a rubidium atomic clock. The method comprises: collecting frequency difference data of the rubidium atomic clock relative to a reference signal; establishing a time-frequency difference model of the rubidium atomic clock according to the frequency difference data and the least squares method; and adjusting the output frequency of the rubidium atomic clock according to the time-frequency difference model and the voltage-frequency fitting relationship. The present application focuses on the frequency drift compensation technology for the aging of key components inside the rubidium atomic clock. By analyzing the drift rate characteristics of the rubidium atomic clock, it is proposed to adjust the accuracy of the output frequency of the rubidium atomic clock by adjusting the voltage-controlled voltage of the constant temperature crystal oscillator inside the rubidium atomic clock, thereby improving the drift rate of the rubidium atomic clock.

The invention provides a clock adjusting method, a clock and electronic equipment, and the method comprises the steps: monitoring an actual value of spectrum data of a target clock; calculating an expected value of the wave spectrum data according to the transmitting power of a target clock corresponding to the actual value on the basis of a predetermined current relationship between the wave spectrum data and the transmitting power; based on the actual value and the expected value, whether deviation exists in the spectrum data of the target clock is judged; if the deviation exists, updating the relationship between the wave spectrum data and the transmitting power based on the actual value of the wave spectrum data and the transmitting power corresponding to the actual value, and obtaining the current relationship between the updated wave spectrum data and the transmitting power; and adjusting the transmitting power of the target clock based on the current relationship between the updated spectrum data and the transmitting power. Through the method, the stability of the clock can be improved.

The invention provides a satellite-borne atomic clock remote discontinuous frequency control method. The method comprises the following steps: acquiring a clock difference between a controlled satellite-borne atomic clock and a space reference clock; performing state estimation on the state quantity of the clock correction by taking the clock correction as input through a Kalman filtering algorithm; according to the clock difference state quantity output by the Kalman filtering algorithm, calculating an optimal frequency control value through an LQR control algorithm; and inputting the optimal frequency control value into the controlled satellite-borne atomic clock to realize frequency control. In this way, the problems that in the spaceborne atomic clock frequency control process, measurement noise is large, and control reference is discontinuous can be solved.

The invention relates to a vacuum packaged chip atomic clock getter activation device and a use method thereof.The getter activation device is arranged to be of a structure with a heating module on the upper portion and a heat dissipation module on the lower portion, and the heating module and the heat dissipation module are not in contact during use; an inner cavity of an upper groove in the heating module is fully attached to a ceramic sealing cap of the chip atomic clock, the upper groove is heated to the optimal activation temperature of the getter through a PTC heating piece, and then heat preservation is conducted for a period of time, so that it is guaranteed that the getter on the inner wall of the ceramic sealing cap is fully activated; in the activation process, the semiconductor cooler and the water cooling plate in the heat dissipation module are started at the same time, the double heat dissipation structure effectively ensures that the In0. 97Ag0. 03 welding ring located in the lower groove is not melted due to overheating, and therefore the long-term stability of the vacuum degree of the chip atomic clock vacuum packaging cavity is guaranteed. The getter activating device has the advantages of being high in heating speed, good in heat dissipation effect, simple in design, convenient to operate, capable of saving cost and the like.

The application discloses a double-resonance atomic clock ultra-miniature substrate integrated waveguide chamber, comprising: a substrate integrated waveguide annular gap cavity, the substrate integrated waveguide annular gap cavity is formed by longitudinal stacking of a plurality of longitudinal slit substrate integrated waveguides, the longitudinal slit substrate integrated waveguide comprises a metalized through hole and a metal microstrip line, and the longitudinal slit substrate integrated waveguide is provided with a longitudinal slit; a MEMS atomic gas chamber; a mode matching excitation structure for exciting a microwave magnetic field to the substrate integrated waveguide annular gap cavity; and an electromagnetic shielding and heating assembly arranged outside the substrate integrated waveguide annular gap cavity. The application can effectively solve the key problem that the resonant performance of a printed miniature annular gap cavity is extremely sensitive to the size change of subwavelength structure parameters, increase the processing tolerance of the ultra-miniature integrated chamber, reduce the processing difficulty and manufacturing cost of high-precision PCB through holes, and improve product yield.

The invention discloses a Galileo satellite clock error medium and short term forecasting method fusing a grey model and a first-order weighted local method, belongs to the field of satellite clock error medium and short term forecasting, and aims to solve the technical bottleneck that a traditional model is difficult to consider both clock error sequence linear drift and nonlinear disturbance. A dynamic prediction framework of wavelet decomposition-reconstruction time sequence maintenance, grey model and local method combined modeling is provided. The method comprises the following steps: firstly, decomposing an original clock error sequence into a low-frequency trend item and a high-frequency detail item through adaptive wavelet decomposition layer number selection, and keeping component time sequence dimension integrity by utilizing a reconstruction algorithm; secondly, precisely fitting deterministic linear drift of a low-frequency component by adopting a gray model, and dynamically capturing nonlinear random disturbance characteristics of a high-frequency component by applying a first-order weighted local method; through a multi-scale dynamic fusion strategy, a weight coefficient is adjusted in combination with a component prediction error real-time feedback mechanism. And a reliable solution is provided for high-precision real-time clock error correction of the satellite navigation system.

The invention provides a CPT atomic clock magnetic field coil constant calibration system and method.The CPT atomic clock magnetic field coil constant calibration system comprises a CPT atomic clock, a frequency measurement module and an upper computer, the upper computer is used for setting the number of times of measurement, calculating a third analog signal in each time of measurement according to a first digital signal in each time of measurement, and sending the third analog signal to the CPT atomic clock; calculating the actual clock transition frequency during each measurement according to the frequency division number of the phase-locked loop circuit and the frequency of the clock signal during each measurement, calculating the external magnetic field during each measurement according to the actual clock transition frequency during each measurement, and finally performing linear fitting according to the external magnetic field during multiple measurements and the third analog signal to obtain a third analog signal; and obtaining a magnetic field coil constant. The invention provides a CPT atomic clock magnetic field coil constant calibration system and method. The system and method are used for solving the problems that a magnetic field coil in a CPT atomic clock is small and cannot be measured, current distribution calculation is complex due to the fact that magnetic shielding is applied, and the actual winding condition of the coil cannot be accurately simulated during simulation.

The invention relates to an atomic clock frequency anomaly detection method, and belongs to the technical field of deep learning and the field of atomic clock anomaly detection. The method comprises the following steps: acquiring a frequency sequence set with a label generated by an atomic clock in a normal frequency sequence injection known abnormal mode; performing supervised training on the anomaly detection model by using the frequency sequence set; in the anomaly detection model, performing feature fusion, nonlinear transformation and classification on a first path of features extracted by performing multilayer decomposition on an input frequency sequence by adopting discrete wavelet transform and a second path of features extracted by adopting a CNN-Transformer network on the input frequency sequence, and then detecting an abnormal frequency sequence; and performing frequency anomaly detection on the atomic clock frequency sequence acquired in real time by using the trained anomaly detection model. According to the invention, high-precision detection of frequency anomalies with different characteristics is realized, the detection range is expanded, and the detection precision is improved.

An atomic clock system includes a waveguide cavity that is sealed and comprises a gas enclosed therein. The waveguide cavity has a length that is an integer multiple of approximately one half-wavelength of a resonant frequency of the gas between two states. An oscillator system generates an RF signal through the waveguide cavity. The RF signal has a signal frequency that is approximately equal to the resonant frequency of the gas. A detection system measures a characteristic of the RF signal through the waveguide cavity to detect a maximum transition between the two states of the gas and to provide a feedback signal to the oscillator system to lock the signal frequency of the RF signal to the resonant frequency of the gas based on detecting the maximum transition. The detection system provides a frequency reference output signal based on the signal frequency of the RF signal.

In a general aspect, a quantum spectrum sensing system is presented. In some implementations, a system includes a laser system, a vapor cell sensor, an optical detector, and a signal processing system. The laser system includes a first laser that generates a first laser signal; a comb generator that produces a frequency comb signal based on the first laser signal; and a second laser generates a second laser signal. The vapor cell sensor includes a vapor and receives input optical signals based on the frequency comb signal and the second laser signal. The vapor cell sensor produces output optical signals based on interactions of the vapor with the input optical signals and electromagnetic radiation. The signal processing system processes the output optical signals to identifying signals in the electromagnetic radiation that are off resonance with a transition frequency between Rydberg states of the vapor.

The embodiment of the invention provides a rubidium atomic clock based on a velocity grating spectrum and an implementation method, and the method comprises the steps: enabling a multi-frequency coherent laser source to emit a laser signal containing the velocity grating spectrum, and dividing the laser signal into two paths through a polarization splitting prism; the reflected light beam enters the laser frequency stabilization module to realize laser frequency stabilization; a transmission light beam enters the rubidium bubble through the lens group to interact with rubidium atoms; the photoelectric tube detects a transition spectral line, converts the transition spectral line from an optical signal into an electric signal and transmits the electric signal to the lock-in amplifier for demodulation; the integral amplification module converts the demodulated direct-current voltage into linear increasing voltage and transmits the linear increasing voltage to the crystal oscillator; the crystal oscillator generates an initial microwave signal and generates a microwave signal corresponding to the 87Rb atom through the frequency synthesizer; and the phase frequency modulation module modulates the microwave signal to obtain an error signal and transmits the error signal to the microwave resonant cavity so as to adjust the electromagnetic field according to the error signal to stably lock the rubidium atomic clock. The method is used for achieving the effect of improving the stability of the rubidium atomic clock system.

The invention discloses a power line fog penetration monitoring method, system and device based on polarization-infrared multi-mode fusion and a medium. An atomic clock is tamed to trigger infrared pulse and polarization exposure, and pixel offset caused by jitter of an unmanned aerial vehicle is compensated through an image motion analysis method; constructing a polarization physical model, and establishing a relationship between the fogdrop particle size and the polarization degree; performing multi-modal feature fusion, constructing a double-branch deep learning network, and performing output judgment on the image according to a dynamic fusion strategy; and optimizing conductor features and insulator features in the power line through a special convolution kernel, and accurately extracting target features.

The embodiment of the invention provides a chip atomic clock based on a speed grating spectrum and an implementation method. Comprising a multi-frequency coherent laser source, a quarter-wave plate, an atomic gas chamber, a photoelectric detector, a band-pass filter, a microwave modulation and demodulation module, a crystal oscillator, a phase-locked loop module, a bias-tree module, a DC modulation and demodulation module and a servo control module. The multi-frequency coherent laser source is sequentially connected with the quarter-wave plate, the atomic gas chamber, the photoelectric detector and the band-pass filter, the first output end of the band-pass filter is sequentially connected with the microwave modulation and demodulation module, the crystal oscillator and the phase-locked loop module, and meanwhile the microwave modulation and demodulation module is connected with the phase-locked loop module. And the second output end of the band-pass filter is connected with the DC modulation-demodulation module and the servo control module in sequence. And the bias-tree module is connected with the servo control module and the phase-locked loop module and feeds back a coupled signal to the multi-frequency coherent laser source so as to complete whole clock locking. The atomic clock is used for achieving the effect of improving the spectral line signal-to-noise ratio.

The invention discloses a method for improving long-term stability of atomic time by using pulsar time, which comprises the following steps: acquiring timing observation data of a pulsar in a preset time period, and fitting timing model parameters of the pulsar; forecasting the time of arrival (TOA) data of the pulsar on the basis of the timing model parameters, meanwhile, continuing to carry out pulsar timing observation by using local atomic time, and comparing the observed TOA sequence with the forecasted TOA data to obtain timing residual data; wiener filtering and classical weighting processing are carried out on timing residual data of multiple pulsar to obtain a clock error sequence of local atomic time and comprehensive pulsar time, a result of smoothing processing of the clock error sequence is negated and then added to the local atomic time, and a new fusion time scale is obtained. According to the method, the paper local atomic time with higher long-term stability can be established, and a powerful guarantee is provided for generating national standard time with higher long-term autonomous retention capability by using a local atomic time control main clock system subsequently.

An optical frequency generation system (100), comprising: - reference atoms (7) in a gas phase, - an interrogation laser source (1) configured to emit an interrogation signal (101) comprising a first optical frequency suitable for exciting a two-photon transition in said reference atoms (7), said interrogation signal (101) being configured to interact with said reference atoms (7) in a Doppler-free scheme; - optical frequency modulation means (31, 31a, 31b) configured to adjust said first optical frequency and to modulate said first optical frequency at a first modulation frequency f1; - an optical sensor (9) configured to detect a fluorescence signal (110) from said reference atoms (7); - a first control loop (10) configured to lock said first optical frequency to a resonance frequency of said two-photon transition, said fluorescence signal (110) being input into the first control loop (10); - a mitigation laser source (2) configured to emit a mitigation signal (102) comprising a second optical frequency selected to produce a light-shift of said two-photon transition of opposite sign of the light-shift produced by the interrogation signal (101); characterized in that the optical frequency generation system (100) further comprises: - optical amplitude modulation means (5) configured to modulate the amplitude of the interrogation signal (101) and of the mitigation signal (102) at a second modulation frequency f2, and - a second control loop (20) configured to adjust the relative amplitude of the mitigation signal (102) with respect to the interrogation signal (101) such as to cancel the effective light-shift of the combined interrogation (101) and mitigation (102) signals.

Provided is an interposer comprising: one or more photonic waveguide; one or more microwave circuit; one or more optical interconnect; and one or more electronic interconnect, further configured to support a quantum sensor, and methods of operating and fabricating thereof. Further provided is a the interposer containing one or more classical sensors. Further provided is a network of quantum sensors supported by said interposers.

The utility model relates to the technical field of chip atomic clocks, particularly provides a micro physical system of a chip atomic clock, and aims to solve the problem that the light transmittance is affected due to the fact that a light-transmitting window of an air chamber of a chip atomic clock in the prior art is easy to pollute. In order to achieve the purpose, the miniature physical system comprises a shielding unit, a magnetic field assembly, a vacuum unit and a center assembly, and the shielding unit is provided with a shielding cavity; the magnetic field assembly sleeves the vacuum unit, and the vacuum unit is provided with a vacuum cavity; the center assembly is arranged in the vacuum cavity and comprises a heating piece, a heat transfer cylinder and an air chamber which are sequentially stacked, a receding notch is formed in the side wall of the heat transfer cylinder, and at least part of the air chamber is arranged outside the heat transfer cylinder through the receding notch. By means of the scheme, steam in the air chamber can be condensed in the air chamber outside the cylinder, the light-transmitting area of the air chamber is avoided, and the problem that the light transmittance is affected due to the fact that the steam is condensed on the light-transmitting face of the air chamber is solved.

The invention discloses a distributed radar time-frequency synchronization and transmit-receive coherent method and system, and belongs to the technical field of radars. The method comprises the following steps: connecting each transmitting station and each receiving station of the distributed radar with a synchronization device, wherein the synchronization device comprises timing system equipment, an atomic clock and wireless communication equipment; the distributed radar receives working parameters issued by the wireless communication center controller to the distributed radar by using the wireless communication equipment; according to the working parameters, the transmitting station starts to transmit a radar signal after receiving a trigger synchronization signal of the timing system equipment, and the receiving station starts to collect an echo signal based on a local oscillator signal after receiving the trigger synchronization signal of the timing system equipment; the radar signal and the local oscillator signal are both generated based on the connected atomic clock as a reference clock. According to the invention, time-frequency synchronization and transmit-receive coherence of the distributed radar can be realized by using the synchronization device, limitation of space wired connection is avoided, and the construction cost of the distributed radar is reduced.

An atomic object confined in a particular region of an atomic object confinement apparatus is cooled using an S-to-P-to-D EIT cooling operation. A controller associated with the atomic object confinement apparatus controls first and second manipulation sources to respectively provide first and second manipulation signals to the particular region. The first manipulation signal is characterized by a first wavelength corresponding to a transition between an S manifold and a P manifold of a first component of the atomic object and detuned from the S-to-P transition by a first detuning. The second manipulation signal is characterized by a second wavelength corresponding to a transition between the P manifold and a D manifold of the first component and detuned from the P-to-D transition by a second detuning. The first and second detunings selected to establish a dark state associated with a two-photon transition between the S manifold and the D manifold.

The invention provides a molecular clock waveguide, a manufacturing method thereof and a molecular clock, relates to the field of molecular clocks, and can realize miniaturization of the molecular clock and long-term stability of air tightness. The molecular clock waveguide includes a first substrate, a first cover plate, and an airbag package. The surface of the first substrate is provided with a main groove and an auxiliary groove. The first cover plate covers the main groove and the auxiliary groove to form a main air chamber and an auxiliary air chamber respectively, and the main air chamber is communicated with the auxiliary air chamber. The air bag package is arranged in the auxiliary air chamber, the air bag package is provided with a first cavity, a shell of the air bag package is provided with a notch, and the first cavity is communicated with the auxiliary air chamber through the notch.

The invention discloses a Beidou PTP master clock device based on chip atomic clock timekeeping, which integrates a chip atomic clock and a Beidou satellite time service signal, and comprises the following steps: firstly, receiving a Beidou satellite signal through a satellite receiving module, and generating an accurate 1PPS signal, a TOD signal and a 10MHz frequency signal based on the satellite signal; high-precision time-frequency reference is provided for equipment, and the problem that clock precision is insufficient in a traditional clock synchronization system is solved through the design. Secondly, the first clock board and the second clock board carry chip atomic clocks, and the high stability and low power consumption characteristics of the chip atomic clocks enable the equipment to maintain high precision of clock signals during long-time operation, so that clock errors caused by crystal oscillator frequency drift and aging in a traditional system are avoided. Moreover, the communication core board is connected with the upper computer, so that instructions can be received in real time, and the clock board and the logic control board can be controlled to work, and therefore, the system can quickly respond to the instructions of the upper computer, and accurate time control can be realized.

The invention discloses a dynamic master clock selection method based on Kalman filtering and Bayesian estimation, which is applied to the technical field of master clock selection, and comprises the following steps: constructing a virtual clock by calculating observation equations of a plurality of atomic clocks; performing state estimation on the atomic clocks by using a Kalman filtering method to obtain state estimation values of the atomic clocks; the state estimation value of each atomic clock comprises the phase and frequency estimation value of the atomic clock; the phase of each atomic clock is the phase deviation of the atomic clock relative to the virtual clock, and the frequency estimation value is the frequency estimation value of the atomic clock relative to the virtual clock; calculating the short-term frequency stability and the long-term frequency drift rate of the atomic clock based on the state estimation value of each atomic clock, and defining the comprehensive performance index of the atomic clock based on the short-term frequency stability and the long-term frequency drift rate; and calculating the posterior probability of each atomic clock based on the comprehensive performance index of each atomic clock and the current observation data by using a Bayesian estimation method so as to perform high-flexibility and high-reliability main clock selection.