High-precision clock synchronization method and system based on Beidou satellite navigation

Abstract

The invention relates to the technical field of clock synchronization, in particular to a high-precision clock synchronization method and system based on Beidou satellite navigation, and the method comprises the steps: a pseudo satellite master station receives a Beidou signal, carries out the processing of capturing, tracking and the like, solves the transmission time and transmission delay, and adjusts a local clock to obtain the local receiving time; the 1PPS pulse is corrected, so that the rising edge of the 1PPS pulse is aligned with the whole second time of the local receiving time; and the master station completes time service by taking the 1PPS as an anchor point, adjusts the telegraph text transmission time delay, and broadcasts time service information to the slave station. And the slave station receives the telegraph text resolving time, calculates the transmitting time and synchronously transmits the telegraph text with the master station, so that the time synchronization of the ground-based pseudo satellite system and the Beidou is realized. According to the method provided by the embodiment of the invention, the unification of the ground-based pseudo satellite system and the Beidou time reference is realized, the problem that the existing system cannot unify the time reference with the Beidou is solved, high-precision time synchronization is ensured, and indoor and outdoor seamless positioning is supported.

Description

Technical Field

[0001] The present disclosure relates to the field of clock synchronization technology, and in particular to a high-precision clock synchronization method and system based on Beidou satellite navigation. Background Art

[0002] As a domestically produced high-precision time system, the Beidou satellite navigation system is widely used in the fields of positioning and timing. Its high-precision ranging relies on a strictly synchronized time base among all parts of the system. Ground-based pseudo-satellites, as a supplement to Beidou's indoor positioning, can provide positioning and timing services in areas where Beidou signals are blocked. The key to seamless connection and continuity of positioning at the junction of the two systems lies in the unification of the time base.

[0003] However, most current ground-based pseudolites are independent systems that only maintain time synchronization between base stations within the system. Some also require synchronization with monitoring stations. This is not only complex to implement, but also lacks a unified time base with the BeiDou system. This limits the use cases of ground-based pseudolites, reduces their scalability, and makes it difficult to achieve joint calculations of BeiDou and pseudolite observations, hindering continuous positioning and seamless handover indoors and outdoors. Therefore, how to solve the series of problems caused by inconsistent time bases and inherent synchronization mechanism defects when existing ground-based pseudolites are used in conjunction with the BeiDou satellite navigation system, thereby improving the stability of indoor positioning, has become a pressing issue. Summary of the Invention

[0004] In view of this, the present disclosure provides a high-precision clock synchronization method and system based on Beidou satellite navigation to solve the series of problems caused by the inconsistent time reference and defects in the synchronization mechanism of the existing ground-based pseudo-satellite system when used in conjunction with the Beidou satellite navigation system, thereby improving the stability of indoor positioning.

[0005] On one hand, the present disclosure provides a high-precision clock synchronization method based on Beidou satellite navigation, which is applied to a ground-based pseudolite system. The ground-based pseudolite system includes a pseudolite master station and a pseudolite slave station. The method includes:

[0006] The pseudolite master station receives BeiDou satellite signals through its built-in BeiDou satellite receiving module, captures, tracks, synchronizes frames, and decodes messages. It then calculates the transmission time and signal transmission delay of the BeiDou satellite signals. Based on the transmission time and signal transmission delay, it adjusts the local clock model and calculates the local reception time.

[0007] After completing the local time calibration, the pseudolite master station corrects the 1PPS pulse-per-second signal so that the rising edge of the corrected 1PPS pulse-per-second signal is aligned with the whole second of the local receiving time, and outputs the aligned 1PPS pulse-per-second signal.

[0008] The pseudolite master station uses the aligned 1PPS pulse-per-second signal as the time anchor point, matches the local reception time received through the serial port with the time anchor point to complete its own timing. It then adjusts the message transmission delay to align the rising edge of the transmission signal at the whole second with the rising edge of the aligned 1PPS pulse-per-second signal, and broadcasts the timing information to the pseudolite slave stations via telegram.

[0009] The pseudolite slave station receives the telegrams broadcast by the pseudolite master station, captures, tracks, frames the telegrams, and performs telegram decoding to determine the time information. It then stores the message reception time in real time and calculates its own transmission time based on the reception time. When the reception time reaches the specified transmission time set by the software, when the pseudolite master station transmits a new frame of telegram, the pseudolite slave station transmits its first frame of telegram at the same time, completing time synchronization with the pseudolite master station and achieving time synchronization between the ground-based pseudolite system and the BeiDou satellite navigation system.

[0010] Another aspect of the present disclosure provides a ground-based pseudo-satellite system, the system comprising:

[0011] The pseudolite master station receives BeiDou satellite signals through its built-in BeiDou satellite receiving module, captures, tracks, synchronizes frames, and decodes messages. It then calculates the transmission time and signal transmission delay of the BeiDou satellite signals. Based on the transmission time and signal transmission delay, it adjusts the local clock model and calculates the local reception time.

[0012] The pseudolite master station is used to correct the 1PPS pulse-per-second signal after completing the local time calibration, so that the rising edge of the corrected 1PPS pulse-per-second signal is aligned with the whole second of the local receiving time, and output the aligned 1PPS pulse-per-second signal;

[0013] The pseudolite master station is used to use the aligned 1PPS pulse-per-second signal as the time anchor point, match the local reception time received through the serial port with the time anchor point to complete its own timing, then adjust the message transmission delay to align the rising edge of the transmission signal at the whole second with the rising edge of the aligned 1PPS pulse-per-second signal, and broadcast the timing information to the pseudolite slave stations through the message;

[0014] The pseudo-satellite slave station is used to receive the telegrams broadcast by the pseudo-satellite master station, capture, track, frame synchronize and decode the telegrams to calculate the time information, latch the telegram reception time in real time, and calculate its own transmission time based on the reception time. When the reception time reaches the specified transmission time set by the software, when the pseudo-satellite master station transmits a new frame of telegram, the pseudo-satellite slave station transmits the first frame of telegram at the same time, completing the time synchronization with the pseudo-satellite master station, so as to realize the time synchronization between the ground-based pseudo-satellite system and the Beidou satellite navigation system.

[0015] On the other hand, the present disclosure also provides an electronic device, including: a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the above-mentioned high-precision clock synchronization method based on Beidou satellite navigation by executing the computer instructions.

[0016] On the other hand, the present disclosure further provides a computer-readable storage medium having computer instructions stored thereon, and the computer instructions are used to enable a computer to implement the above-mentioned high-precision clock synchronization method based on Beidou satellite navigation.

[0017] On the other hand, the present disclosure further provides a computer program product, including computer instructions, which are used to enable a computer to execute the above-mentioned high-precision clock synchronization method based on Beidou satellite navigation.

[0018] Through the high-precision clock synchronization method and system based on Beidou satellite navigation of the above-mentioned embodiments of the present disclosure, the Beidou satellite receiving module built into the pseudolite master station receives Beidou satellite signals and calculates time information, completes its own timing with the 1PPS second pulse as the time anchor point, and then synchronizes the slave station with the master station by broadcasting the timing information through telegrams. Ultimately, the time base of the entire ground-based pseudolite system is kept consistent with that of the Beidou satellite navigation system, solving the problem that the existing ground-based pseudolite system cannot unify its time base with Beidou.

[0019] In addition, since there is no need for additional monitoring stations, the pseudo-satellite master station directly uses Beidou satellite signals to complete time synchronization, and the slave station can achieve time synchronization with the master station by receiving the telegrams broadcast by the master station, avoiding the complex implementation method brought about by some existing ground-based pseudo-satellite systems relying on monitoring stations to achieve synchronization, and improving the maintainability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific embodiments of the present disclosure or the technical solutions in the related technologies, the following briefly introduces the drawings required for use in the specific embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1a This is a schematic diagram of the architecture and process flow of a ground-based pseudo-satellite system used in a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure;

[0022] Figure 1b This is a flowchart of a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure;

[0023] Figure 2This is a schematic diagram of the architecture and process flow of an indoor and outdoor seamless positioning and timing system applied to a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure;

[0024] Figure 3 This is a schematic diagram of a specific process of a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure;

[0025] Figure 4 This is a schematic diagram of adjusting the message transmission time of a ground-based pseudo-satellite system based on a high-precision clock synchronization method of Beidou satellite navigation provided by an embodiment of the present disclosure;

[0026] Figure 5 This is a structural diagram of another ground-based pseudo-satellite system provided by an embodiment of the present disclosure.

[0027] Figure 6 This is a schematic structural diagram of another ground-based pseudo-satellite system provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0028] BeiDou, a domestically produced navigation system, is widely used for positioning and timing in daily life. Essentially, it is a high-precision time system. The acquisition of high-precision ranging observations relies on maintaining a strictly synchronized time base across all components of the system. Ground-based pseudolites, as an effective complement to the BeiDou system for indoor positioning, can provide positioning and timing services to users in areas where BeiDou signals are obstructed. A unified time base is crucial for maintaining seamless and continuous positioning at the interface between the two systems.

[0029] Currently, most ground-based pseudolites operate as self-contained systems, solely responsible for maintaining time synchronization between base stations within the system. Some ground-based pseudolites also require the assistance of monitoring stations for system-wide time synchronization. This approach is not only complex to implement but also fails to align with the BeiDou time base. This limits the use cases for ground-based pseudolites, reduces their scalability, and further complicates the joint computation of BeiDou and pseudolite observations, hindering continuous positioning and seamless handovers both indoors and outdoors.

[0030] To solve the above problems, various embodiments of the present disclosure provide a high-precision clock synchronization method based on Beidou satellite navigation, which is applied to a ground-based pseudo-satellite system. The ground-based pseudo-satellite system includes a pseudo-satellite master station and a pseudo-satellite slave station. The method includes: the pseudo-satellite master station receives Beidou satellite signals through its built-in Beidou satellite receiving module, captures, tracks, synchronizes frames and performs telegram decoding on the Beidou satellite signals, and decodes the transmission time and signal transmission delay of the Beidou satellite signals. Based on the transmission time and signal transmission delay, the local clock model is adjusted to calculate the local reception time; after completing the local time calibration, the pseudo-satellite master station corrects the 1PPS second pulse signal so that the rising edge of the corrected 1PPS second pulse is aligned with the whole second of the local reception time, and outputs the aligned 1PPS second pulse signal; the pseudo-satellite master station uses the The aligned 1PPS pulse-per-second signal is used as the time anchor point. The local receive time received through the serial port is matched with the time anchor point to complete its own timing. The telegram transmission delay is then adjusted to align the rising edge of the transmission signal at the whole second with the rising edge of the aligned 1PPS pulse-per-second signal. The timing information is then broadcast to the pseudolite slave station via telegram. The pseudolite slave station receives the telegram broadcast by the pseudolite master station, captures, tracks, performs frame synchronization, and performs telegram decoding to calculate the time information. The telegram reception time is latched in real time, and its own transmission time is calculated based on the reception time. When the reception time reaches the specified transmission time set by the software, when the pseudolite master station transmits a new frame of telegram, the pseudolite slave station transmits the first frame of telegram at the same time, completing time synchronization with the pseudolite master station, thereby achieving time synchronization between the ground-based pseudolite system and the BeiDou satellite navigation system.

[0031] To make the purpose, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present disclosure.

[0032] Please refer to Figure 1a , Figure 1a This is a schematic diagram of the architecture of a ground-based pseudo-satellite system used in a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure, as shown in the flow chart. Figure 1a As shown, the ground-based pseudolite system 100 includes a pseudolite master station 101 and a pseudolite slave station 102, wherein:

[0033] The ground-based pseudo-satellite system 100 is a supplementary system for indoor positioning of the Beidou satellite navigation system. It is used to provide positioning and timing services to users in areas where the Beidou signal is blocked. Its core goal is to achieve time synchronization with the Beidou system to ensure seamless connection between indoor and outdoor positioning.

[0034] Furthermore, the pseudolite master station 101 is the core control node of the ground-based pseudolite system 100. It has a built-in Beidou satellite receiving module and is placed in an open outdoor environment. It is responsible for receiving Beidou satellite signals and calculating time information, correcting the 1PPS second pulse to align with the whole second, and then adjusting the message transmission delay with 1PPS as the anchor point. It broadcasts timing information to the pseudolite slave station 102, completes its own timing and provides a time reference for the system.

[0035] Pseudolite slave station 102 is a subordinate node of the ground-based pseudolite system 100. It receives messages broadcast by pseudolite master station 101, extracts time information through calculation, latches the reception time in real time, and calculates its own transmission time. When pseudolite master station 101 transmits a new frame of message, it transmits its first frame of message synchronously, achieving time synchronization with pseudolite master station 101 and ensuring that the ground-based pseudolite system 100 is consistent with the BeiDou system time.

[0036] Please refer to Figure 1b , Figure 1b : This is a flow chart of a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure. The flow of the method may include the following steps:

[0037] In step S101, the pseudolite master station receives Beidou satellite signals through its built-in Beidou satellite receiving module, captures, tracks, synchronizes frames, and decodes messages on the Beidou satellite signals, calculates the transmission time and signal transmission delay of the Beidou satellite signals, adjusts the local clock model based on the transmission time and signal transmission delay, and calculates the local reception time.

[0038] In this embodiment, the pseudolite master station is placed outdoors in an open environment. After receiving BeiDou satellite signals, the BeiDou satellite receiving module within the pseudolite master station sequentially performs acquisition, tracking, frame synchronization, and message decoding. Acquisition locks onto the satellite signal, tracking maintains stable signal reception, frame synchronization aligns the signal with the satellite message frame structure, and message decoding extracts navigation message information from the signal.

[0039] Through message decoding, the second count of the week of the current subframe is extracted from the navigation message to achieve second-level time information acquisition; the bit counter is used to determine the position of the current bit in the subframe, and the time accuracy is improved to 20ms; through pseudocode cycle counting (one pseudocode cycle is 1ms, and one bit contains 20 pseudocode cycles), the accuracy is improved to 1ms; combined with the local pseudocode instantaneous phase recorded by the pseudocode tracking loop (one code cycle contains 10230 code phases), the Beidou satellite signal transmission time is finally calculated with an accuracy of nanoseconds.

[0040] Based on information such as satellite position and master station position, the path delay during signal transmission is calculated, while taking into account and correcting satellite clock error, ionospheric delay and tropospheric delay.

[0041] Based on the calculated satellite signal transmission time and various delay parameters, the local clock model of the master station is adjusted to calculate the local reception time and complete the precise calibration of the local time.

[0042] In step S102, after completing the local time calibration, the pseudolite master station corrects the 1PPS pulse-per-second signal so that the rising edge of the corrected 1PPS pulse-per-second signal is aligned with the whole second of the local receiving time, and outputs the aligned 1PPS pulse-per-second signal.

[0043] In this embodiment, after the pseudolite master station completes the calculation of the local reception time in step S101, it confirms that the local clock model has been calibrated based on the Beidou satellite signal to ensure that the local reception time is consistent with the Beidou system time reference.

[0044] The BeiDou satellite receiving module outputs the original 1PPS pulse-per-second signal. The initial state of the signal may deviate from the local receiving time by one whole second.

[0045] The master station uses the clock comparison unit to detect the time deviation between the rising edge of the original 1PPS second pulse and the local receiving time in real time and record the deviation value.

[0046] According to the detected deviation value, the output time of the 1PPS second pulse signal is adjusted through the time correction circuit inside the master station, so that the rising edge of the corrected 1PPS second pulse is accurately aligned with the whole second of the local receiving time, eliminating the deviation.

[0047] After the correction is completed, the master station outputs the aligned 1PPS second pulse signal as the time anchor point for the subsequent pseudo-satellite master station's own timing and message transmission time adjustment.

[0048] In step S103, the pseudolite master station uses the aligned 1PPS pulse-per-second signal as the time anchor point, matches the local reception time received through the serial port with the time anchor point to complete its own timing, then adjusts the message transmission delay so that the rising edge of the transmission signal at the whole second is aligned with the rising edge of the aligned 1PPS pulse-per-second signal, and broadcasts the timing information to the pseudolite slave station via a message.

[0049] In this embodiment, the pseudolite master station uses the aligned 1PPS pulse-per-second signal outputted in step S102 as a time anchor point, and the rising edge of the anchor point is precisely aligned with the whole second of the local receiving time.

[0050] The master station receives the local reception time output by the Beidou satellite receiving module through the serial port, matches the time information with the time anchor point of the 1PPS second pulse, and completes the master station's own timing calibration based on the whole second corresponding to the anchor point.

[0051] When the master station detects the input of the 1PPS second pulse signal, it latches the number of bits remaining to be sent in the message FIFO (first-in-first-out buffer) at this time, and splices and fills the message bits accordingly according to the remaining number of bits to ensure the integrity of the message structure.

[0052] Adjust the message transmission delay so that the rising edge of the first bit of the message carrying the timing information is strictly aligned with the rising edge of the 1PPS second pulse signal, ensuring that the rising edge of the transmitted signal at the whole second is consistent with the rising edge of the time anchor point.

[0053] The time of the first bit of the transmitted timing message is calculated based on the local reception time received by the serial port, and the timing information in the message is updated using this time. The signal containing the updated timing information is then broadcast to the pseudo-satellite slave station via the message.

[0054] In step S104, the pseudolite slave station receives the message broadcast by the pseudolite master station, captures, tracks, performs frame synchronization, and performs message decoding to determine time information. The pseudolite slave station then stores the message reception time in real time and calculates its own transmission time based on the reception time. When the reception time reaches the designated transmission time set by the software, the pseudolite slave station transmits its first message frame at the same time as the pseudolite master station transmits a new message frame, thereby completing time synchronization with the pseudolite master station and achieving time synchronization between the ground-based pseudolite system and the BeiDou satellite navigation system.

[0055] In this embodiment, the pseudolite slave station receives the message signal broadcast by the pseudolite master station in real time, and performs acquisition, tracking, and frame synchronization operations in sequence to stably lock onto the master station signal and align with the message frame structure.

[0056] By analyzing the telegram, the time information such as the second count within the week of the current telegram frame is parsed, and the timing reference transmitted by the master station is obtained.

[0057] The slave station latches the moment it receives the master station message in real time as a reference point for its own time calibration.

[0058] Based on the latched reception time, the positional relationship between the master and slave stations, and the signal transmission characteristics, the time when the slave station should transmit the message is calculated.

[0059] When the slave detects that the receiving time reaches the designated transmitting time preset by the software, it enters the synchronous transmission waiting state.

[0060] At the same time when the master station transmits a new frame of telegram, the slave station transmits its own first frame of telegram, realizing time synchronization between the master and slave stations, thereby making the time base of the entire ground-based pseudo-satellite system consistent with that of the Beidou satellite navigation system.

[0061] Through the high-precision clock synchronization method and system based on Beidou satellite navigation of the above-mentioned embodiment of the present disclosure, step S101 uses multi-level solution of Beidou satellite signals (from seconds to nanoseconds), combined with satellite clock error, ionospheric delay correction, etc., to make the local reception time obtained by the pseudo-satellite master station consistent with the Beidou system time at the nanosecond level, providing a high-precision time reference for the entire system, meeting the stringent requirements for time synchronization for indoor and outdoor positioning. Step S102 corrects the 1PPS second pulse, converting the Beidou system time reference into the physical signal anchor point of the pseudo-satellite master station, ensuring accurate alignment of the whole second moment, providing a unified reference for subsequent master station timing and message transmission, and solving the core problem of the inconsistency between the existing pseudo-satellite system and the Beidou time reference. In step S103, the master station directly completes timing and broadcasts information using the 1PPS as the anchor point. In step S104, the slave station achieves synchronization by receiving the master station signal without the participation of additional monitoring stations, simplifying the synchronization architecture of the traditional pseudo-satellite system, reducing implementation complexity, and improving the maintainability and scalability of the system. The time synchronization between the master station and the Beidou system, and the real-time synchronization between the slave station and the master station ensure the complete unification of the time base between the ground-based pseudo-satellite system and the Beidou system, providing continuous and seamless time support for positioning switching between the Beidou signal coverage area and the pseudo-satellite coverage area (such as the interface between indoor and outdoor areas), and realizing uninterrupted connection between the joint solution of observation quantities and positioning services.

[0062] In a possible implementation of step S101, the transmission time of the Beidou satellite signal calculated by the pseudolite master station is at nanosecond level accuracy.

[0063] In this embodiment, the pseudo-satellite master station uses a built-in Beidou satellite receiving module to perform hierarchical calculations on the Beidou satellite signal, gradually improving the time accuracy to the nanosecond level. The specific process is as follows: the second count of the week in the current subframe is parsed from the navigation message to directly obtain the second-level time information; the position of the current bit in the subframe is determined by a bit counter (a subframe contains a fixed number of bits), and the time accuracy is improved to 20ms; combined with the pseudo-code cycle count (1 bit contains 20 1ms pseudo-code cycles), the accuracy is further improved to 1ms; and the local pseudo-code instantaneous phase recorded by the pseudo-code tracking loop (1 code cycle contains 10230 code phases) is used to finally calculate the Beidou satellite signal transmission time with an accuracy of 0.098ns through phase calculation.

[0064] Through the high-precision clock synchronization method and system based on Beidou satellite navigation of the above-mentioned embodiments of the present invention, the nanosecond-level satellite launch time is the core basis for the pseudo-satellite master station to calibrate the local clock, ensuring that the deviation between the local receiving time of the master station and the Beidou system time is controlled at the nanosecond level, providing a source-level high-precision time reference for subsequent 1PPS second pulse correction and message transmission delay adjustment; since the launch time accuracy reaches the nanosecond level, the observation quantities of Beidou satellites and pseudo-satellites are consistent in the time dimension, solving the problem of "Beidou-pseudo-satellite observation quantities cannot be jointly solved" due to insufficient time accuracy in the prior art, and providing the possibility for the fusion processing of indoor and outdoor positioning data; nanosecond-level time synchronization ensures that when the user terminal switches from the Beidou system to the pseudo-satellite system when switching indoors and outdoors, the time jump when switching from the Beidou system to the pseudo-satellite system is negligible, avoiding positioning interruption or sudden drop in accuracy, and ultimately achieving seamless connection of indoor and outdoor positioning.

[0065] In a possible implementation of step S101, when the pseudolite master station calculates the local reception time, factors also taken into consideration include: satellite clock error, ionospheric delay, and tropospheric delay.

[0066] In this embodiment, when calculating the local reception time, the pseudolite master station needs to comprehensively correct the following delay factors based on the nanosecond-level satellite transmission time:

[0067] Satellite clock error: The deviation between the Beidou satellite's own clock and the ideal Beidou system time needs to be corrected by a mathematical model using the clock error parameters (such as clock error, clock speed, and clock drift) in the navigation message;

[0068] Ionospheric delay: The propagation delay caused by the electron density distribution when the signal passes through the Earth's ionosphere can be calculated and eliminated using the ionospheric model or dual-frequency observation data provided by the Beidou message;

[0069] Tropospheric delay: The delay caused by the atmospheric refractive index when the signal propagates in the troposphere (the lower layer of the atmosphere). This needs to be corrected using a tropospheric model based on the geographic location of the master station (such as latitude and altitude) and meteorological parameters (such as temperature, air pressure, and humidity).

[0070] Path delay: The time delay corresponding to the straight-line propagation distance between the satellite and the master station, calculated from the satellite position and the known position of the master station (speed of light × spatial distance).

[0071] The high-precision clock synchronization method and system based on Beidou satellite navigation of the above-mentioned embodiments of the present disclosure eliminates interference of non-ideal factors on time transmission by correcting errors such as satellite clock errors, ionosphere, and troposphere, so that the deviation between the local receiving time of the master station and the Beidou system time is controlled at the nanosecond level, thereby achieving the source unification of the pseudolite system and the Beidou time reference. Compared with the practice of ignoring some delays (or only roughly correcting them) in the prior art, the comprehensive delay correction avoids fluctuations in synchronization accuracy caused by environmental factors (such as weather changes and satellite position changes), ensuring that the pseudolite system can still maintain high-precision time synchronization in complex scenarios. The precise delay correction makes the observations of Beidou and pseudolite comparable in the time dimension, providing a reliable time reference for subsequent Beidou-pseudolite joint positioning solution, and solving the problem of failure of joint solution due to excessive time error in the prior art.

[0072] In one possible implementation of step S103, the pseudo-satellite master station adjusts the message transmission delay, including: the pseudo-satellite master station latches the number of remaining bits to be sent in the message FIFO at the time the aligned 1PPS pulse second signal is input, and accordingly splices and fills the message bits to ensure that the rising edge of the first bit of the message carrying the timing information is aligned with the rising edge of the aligned 1PPS pulse second signal.

[0073] In this embodiment, when the master station detects the input of the aligned 1PPS second pulse signal, it immediately latches the number of remaining bits to be sent in the telegram FIFO (first-in-first-out buffer) and records the real-time status of the telegram transmission; based on the latched number of remaining bits to be sent, the master station dynamically splices and fills the telegram, supplements the necessary bit data to improve the telegram structure, and ensures the integrity of the telegram; through the above operations, the rising edge of the first bit of the telegram carrying timing information is strictly aligned with the rising edge of the 1PPS second pulse signal, and ultimately achieves precise synchronization of the transmission signal and the time anchor point at the whole second.

[0074] The high-precision clock synchronization method and system based on Beidou satellite navigation, as described in the above-mentioned embodiments of the present disclosure, aligns the rising edge of the first bit of the message with the 1PPS second pulse, embedding the Beidou system's high-precision time reference (converted via the 1PPS anchor point) into the pseudolite message. This allows slave stations to directly obtain the synchronization reference by receiving the message, thus resolving the issue of the physical carrier for time transmission between the pseudolite system and the Beidou system. The strict alignment of the first bit of the message with the 1PPS ensures that the timing information contained in the message (such as the seconds per week) is consistent with the transmission time, avoiding slave station calculation errors due to time deviations and improving the reliability of the timing information.

[0075] In a possible implementation of the above step embodiment, the message transmitted by the pseudolite master station is a 1ms / 10ms time slot signal, the ratio of effective time slot to time slot is 1:10, the number of code cycles in the message bit is 1, and the number of bits in the frame is 300.

[0076] In this embodiment, the message transmitted by the pseudolite master station adopts a specific signal system, and the specific parameters are as follows:

[0077] Time slot structure: The message is a 1ms / 10ms time slot signal, that is, the ratio of valid time slots (time slots containing actual timing information) to non-valid time slots (idle or auxiliary time slots) is fixed at 1:10;

[0078] Code period configuration: Each message bit contains one code period;

[0079] Frame structure: Each frame of telegram contains 300 bits, forming a fixed frame length and data capacity.

[0080] Through the high-precision clock synchronization method and system based on Beidou satellite navigation of the above-mentioned embodiments of the present invention, the 1ms / 10ms time slot design can reduce the interference of indoor multipath effects on signals, reduce the impact of signal blocking or reflection by shortening the effective time slot length, and improve the stability of the slave station receiving signals; the configuration of 1 code period within a bit and 300 bits within a frame ensures the complete transmission of timing information (such as the second count within the week, the master station timestamp, etc.) while avoiding the synchronization delay caused by an excessively long frame structure, taking into account both time synchronization accuracy and data transmission efficiency; the pseudo-satellite message system is different from the Beidou satellite signal (non-homologous signal system), which can reduce the conflict between the two in signal frequency bands or modulation methods, ensure that indoor pseudo-satellite signals and outdoor Beidou signals coexist at the junction without interfering with each other, and provide signal-level compatibility guarantees for seamless switching.

[0081] In a possible implementation of the above step embodiment, the method further includes:

[0082] After receiving the local reception time through the serial port, the pseudo-satellite master station calculates the time of the first bit of the transmitted timing message and uses this time to update the timing information;

[0083] The pseudolite slave station decodes the message to determine the time information, including the seconds of the week of the current message frame.

[0084] In this embodiment, the pseudolite master station updates the timing information: after receiving the calibrated local reception time through the serial port, the pseudolite master station calculates the actual transmission time of the first bit of the timing message in combination with the message transmission delay adjustment strategy; and embeds this transmission time into the timing information field of the message to complete the dynamic update of the timing information, ensuring that the time stamp in the message is consistent with the actual transmission time.

[0085] Pseudo-satellite slave station calculates time information: When a pseudo-satellite slave station calculates the received master station message, it focuses on extracting the second count of the week contained in the current message frame. This count directly corresponds to the time reference of the Beidou system and serves as the core basis for the slave station's own time calibration.

[0086] Through the high-precision clock synchronization method and system based on Beidou satellite navigation of the above-mentioned embodiment of the present disclosure, the master station calculates and updates the transmission time of the first bit of the telegram through the serial port time, so that the timing information is strictly bound to the physical transmission process, avoiding the invalidation of the time mark due to transmission delay or processing time, and improving the accuracy of the timing information. The slave station can directly obtain the Beidou time reference transmitted by the master station by solving the second count within the week, without the need for complex time conversion or additional parameters, reducing the computational load of the slave station and realizing rapid alignment of the master and slave station time. The second count within the week is a standardized time parameter of the Beidou system, which ensures the homology of the time information solved by the slave station and the Beidou system time, and ultimately realizes the deep unification of the time reference between the ground-based pseudo-satellite system and the Beidou system, providing a consistent time reference for indoor and outdoor joint positioning.

[0087] In one embodiment, please refer to Figure 2 , Figure 2 This is a schematic diagram of the architecture of a seamless indoor and outdoor positioning and timing system for a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure, as shown in the flow chart. Figure 2 As shown: the indoor and outdoor seamless positioning and timing system 200 includes BeiDou satellites 201, pseudolite master stations 202, pseudolite slave stations 203 and user terminals 204, wherein:

[0088] BeiDou satellite 201, located in outer space, serves as a high-precision time reference source, continuously broadcasting satellite signals containing time information to the ground, providing the original time reference for the entire system. Pseudo-satellite master station 202, deployed outdoors in an open environment (ensuring unobstructed reception of BeiDou signals), houses a built-in BeiDou satellite receiving module capable of capturing and tracking BeiDou satellite signals and calculating time information. It also serves as the core node of the ground-based pseudo-satellite system 100, responsible for broadcasting timing messages to pseudo-satellite slave stations.

[0089] The pseudolite slave station 203 is deployed in indoor environments (such as tunnels, buildings and other areas where Beidou signals are blocked). It completes time synchronization by receiving messages broadcast by the pseudolite master station 202 and cooperates with the pseudolite master station 202 to provide positioning and timing services for indoor users.

[0090] The user terminal 204 includes various devices that require positioning and timing functions (such as navigation terminals, Internet of Things devices, etc.), which can receive Beidou signals outdoors, receive pseudo-satellite signals indoors, or receive both types of signals at the junction to achieve seamless switching.

[0091] Among them, Beidou satellite 201 sends satellite signals containing high-precision time information to pseudolite master station 202; pseudolite master station 202 parses the Beidou signal to obtain a time reference, calibrates the local clock, and then broadcasts synchronous timing information to indoor pseudolite slave station 203 by adjusting the message transmission delay; pseudolite slave station 203 receives the signal from pseudolite master station 202 and completes time synchronization, forming a positioning and timing network covering the indoor area with pseudolite master station 202; when user terminal 204 moves indoors or outdoors, it automatically switches to receive Beidou satellite 201 or pseudolite signals. Since the two types of signals are based on the same time reference, continuous and uninterrupted positioning and timing services are achieved.

[0092] In one embodiment, please refer to Figure 3 , Figure 3 This is a schematic diagram of a specific process of a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure. The process may include the following steps:

[0093] When the master station detects the PPS_IN (1PPS pulse per second signal) input, it immediately triggers the transmission time adjustment mechanism. By latching the number of remaining bits to be sent in the message FIFO at this time (such as "Bitn, Bitn+1, Bitn+2" in the figure), it dynamically splices and fills the message bits to ensure that the rising edge of the first bit of the message containing timing information is strictly aligned with the rising edge of PPS_IN.

[0094] After receiving the local reception time (t) through the serial port, the master station calculates the actual transmission time of the first bit of the timing message in combination with the whole second of PPS_IN, and uses this time to update the timing information in the message (such as the second count in the week), thus binding the time information with the physical transmission process.

[0095] In the figure, "SlotN+1" represents a valid time slot (1ms) transmitted by the master station. The "idle time slots" before and after it (10ms each) constitute a time slot ratio of 1:10, which conforms to the system characteristics of the pseudo-satellite signal "1ms / 10ms time slot signal", ensuring efficient transmission of telegrams between the master station and the slave station.

[0096] Among them, PPS_IN (1PPS pulse per second signal) is output by the Beidou satellite receiving module and serves as the physical anchor point for master station time synchronization. Its rising edge has been precisely aligned with the whole second of the local receiving time through correction (see step S102); the serial port timing (t) refers to the local receiving time (t) transmitted by the Beidou satellite receiving module to the master station through the serial port. u ), contains nanosecond-level precision time information, which is used by the master station to update the timing content in the telegram; the telegram FIFO (first-in-first-out buffer) is used to temporarily store the telegram bit data to be transmitted by the master station, ensuring the continuity and integrity of the telegram transmission.

[0097] In one embodiment, please refer to Figure 4 , Figure 4 Schematic diagram of adjusting the message transmission time of a ground-based pseudo-satellite system using a high-precision clock synchronization method based on Beidou satellite navigation provided by an embodiment of the present disclosure, wherein:

[0098] In the upper part, the message transmission time is not adjusted. Without the transmission delay adjustment, the transmission rhythm of the bit sequence (such as Bit 1 to Bit 300) of the message frame (frame number n, frame number n+1) has no fixed correlation with the rising edge of PPS_IN, resulting in a misalignment between the whole second time (PPS_IN rising edge) and the rising edge of the message signal. At this time, the time information of the message cannot be bound to the Beidou system time reference, making it difficult for the slave station to achieve high-precision synchronization after receiving it. In the lower part, the message transmission delay is adjusted after being synchronized. After the master station is synchronized, alignment is achieved through the following mechanisms:

[0099] When the PPS_IN input is detected, the remaining number of bits to be sent in the message FIFO is immediately latched (such as the remaining bits of frame number n in the figure), and the message data is dynamically spliced ​​and filled;

[0100] Adjust the transmission rhythm of frame number n+1 so that the rising edge of the first bit (Bit1) of the new frame message is precisely aligned with the rising edge of PPS_IN (in the whole second);

[0101] The bit sequences of subsequent frames (such as frame number n+1) are transmitted according to a fixed timing sequence to ensure that the time base of each frame of the message is consistent with PPS_IN.

[0102] Here, the adjustment process corrects the message transmission delay and embeds the Beidou system's whole-second time reference into the pseudo-satellite message transmission timing. After receiving the message, the slave station can directly achieve time synchronization by comparing the rising edge of the first bit with its own 1PPS signal. Ultimately, it ensures the time reference of the entire ground-based pseudo-satellite system and the Beidou system is unified, providing key support for seamless indoor and outdoor positioning.

[0103] In one embodiment, a ground-based pseudo-satellite system 500 is provided, which corresponds one-to-one with the high-precision clock synchronization method based on Beidou satellite navigation in the above embodiment. Figure 5 As shown, the ground-based pseudolite system 500 includes a pseudolite master station 501 and a pseudolite slave station 502, wherein each functional module is described in detail as follows:

[0104] The pseudolite master station 501 is used to receive Beidou satellite signals through its built-in Beidou satellite receiving module, capture, track, frame synchronize, and decode Beidou satellite signals, calculate the transmission time and signal transmission delay of the Beidou satellite signals, adjust the local clock model based on the transmission time and signal transmission delay, and calculate the local reception time;

[0105] The pseudolite master station 501 is configured to correct the 1PPS pulse-per-second signal after completing the local time calibration, so that the rising edge of the corrected 1PPS pulse-per-second signal is aligned with the whole second of the local receiving time, and output the aligned 1PPS pulse-per-second signal;

[0106] The pseudolite master station 501 is configured to use the aligned 1PPS pulse-per-second signal as a time anchor point, match the local reception time received through the serial port with the time anchor point to complete its own timing, then adjust the message transmission delay to align the rising edge of the transmission signal at the whole second with the rising edge of the aligned 1PPS pulse-per-second signal, and broadcast the timing information to the pseudolite slave station 502 via a message;

[0107] Pseudolite slave station 502 is configured to receive messages broadcast by pseudolite master station 501, capture, track, perform frame synchronization, and perform message decoding to determine time information. It then stores the message reception time in real time and calculates its own transmission time based on the reception time. When the reception time reaches the designated transmission time set by the software, when pseudolite master station 501 transmits a new message frame, pseudolite slave station 502 simultaneously transmits its first message frame, completing time synchronization with pseudolite master station 501 and achieving time synchronization between the ground-based pseudolite system and the BeiDou satellite navigation system.

[0108] In one embodiment, the transmission time of the BeiDou satellite signal calculated by the pseudolite master station 501 is at nanosecond level accuracy.

[0109] In one embodiment, when the pseudo-satellite master station 501 is used to calculate the local reception time, factors also include: satellite clock error, ionospheric delay, and tropospheric delay.

[0110] In one embodiment, the pseudo-satellite master station 501 is used to latch the number of remaining to-be-sent bits in the message FIFO at the time of input of the aligned 1PPS pulse-per-second signal, and to splice and fill the message bits accordingly to ensure that the rising edge of the first bit of the message carrying the timing information is aligned with the rising edge of the aligned 1PPS pulse-per-second signal.

[0111] In one embodiment, the message transmitted by the pseudolite master station 501 is a 1ms / 10ms time slot signal, the ratio of effective time slot to time slot is 1:10, the number of code cycles in the message bit is 1, and the number of bits in the frame is 300.

[0112] In one embodiment, the pseudolite master station 501 is further configured to calculate the time of transmitting the first bit of the timing message after receiving the local reception time via the serial port, and use the time to update the timing information;

[0113] The pseudolite slave station 502 is further used to decode the message to obtain time information, specifically including decoding the seconds of the week of the current message frame.

[0114] It should be noted that: the ground-based pseudo-satellite system provided in the above embodiment is only illustrated by the division of the above program modules when implementing the corresponding switch delay measurement and compensation method for the converter. In actual application, the above processing can be assigned to different program modules as needed, that is, the internal structure of the above system can be divided into different program modules to complete all or part of the above-described processing. In addition, the system provided in the above embodiment and the corresponding Figure 1b The embodiments of the method shown belong to the same concept, and their specific implementation processes are detailed in the method embodiments, which will not be repeated here.

[0115] The present disclosure also provides an electronic device having the above Figure 1a 、 Figure 5 The ground-based pseudo-satellite system shown.

[0116] See also Figure 6 , Figure 6 FIG. 1 is a structural diagram of another ground-based pseudo-satellite system provided by an embodiment of the present disclosure. Figure 6 As shown, the electronic device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. The various components utilize different buses to communicate with each other and can be installed on a common mainboard or installed in other ways as needed. The processor can process instructions executed in the electronic device, including instructions stored in or on the memory to display graphical information of a GUI on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple electronic devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 6 A processor 10 is taken as an example.

[0117] The processor 10 may be a central processing unit, a network processor, or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit, a programmable logic device, or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic, or any combination thereof.

[0118] The memory 20 stores instructions that can be executed by at least one processor 10, so as to enable at least one processor 10 to execute the method shown in the above embodiment.

[0119] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and applications required for at least one function; the data storage area may store data created based on the use of the electronic device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely located relative to the processor 10, and these remote memories may be connected to the electronic device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0120] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid-state drive; the memory 20 may also include a combination of the above types of memory.

[0121] The electronic device further includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30 and the output device 40 may be connected via a bus or other means. Figure 6 The bus connection is taken as an example.

[0122] The input device 30 can receive input digital or character information and generate key signal input related to user settings and function control of the electronic device, such as a touch screen, a keypad, a mouse, a trackpad, a touch pad, an indicator stick, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 can include a display device, an auxiliary lighting device (e.g., an LED), and a tactile feedback device (e.g., a vibration motor). The above-mentioned display device includes but is not limited to a liquid crystal display, a light emitting diode, a display, and a plasma display. In some optional embodiments, the display device can be a touch screen.

[0123] The electronic device also includes a communication interface for the electronic device to communicate with other devices or a communication network.

[0124] The embodiments of the present disclosure also provide a computer-readable storage medium. The above-mentioned method according to the embodiments of the present disclosure can be implemented in hardware, firmware, or implemented as a computer code that can be recorded in a storage medium, or implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and downloaded through a network and will be stored in a local storage medium, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state drive, etc.; further, the storage medium can also include a combination of the above-mentioned types of memory. It can be understood that a computer, a processor, a microprocessor controller or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor or hardware, the method shown in the above embodiment is implemented.

[0125] A portion of the present disclosure may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present disclosure through the operation of the computer. Those skilled in the art should understand that the form in which the computer program instruction exists in a computer-readable medium includes but is not limited to a source file, an executable file, an installation package file, etc. Accordingly, the way in which the computer program instruction is executed by the computer includes but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium that can be accessed by the computer.

[0126] Although the embodiments of the present disclosure have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present disclosure, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A high-precision clock synchronization method based on Beidou satellite navigation, characterized in that: Applied to a ground-based pseudolite system, the ground-based pseudolite system includes a pseudolite master station and a pseudolite slave station, and the method includes: The pseudolite master station receives Beidou satellite signals through its built-in Beidou satellite receiving module, captures, tracks, synchronizes frames, and decodes messages on the Beidou satellite signals, calculates the transmission time and signal transmission delay of the Beidou satellite signals, adjusts the local clock model based on the transmission time and signal transmission delay, and calculates the local reception time; After completing the local time calibration, the pseudolite master station corrects the 1PPS pulse-second signal so that the rising edge of the corrected 1PPS pulse-second signal is aligned with the whole second of the local receiving time, and outputs the aligned 1PPS pulse-second signal; The pseudolite master station uses the aligned 1PPS pulse-per-second signal as a time anchor point, matches the local reception time received through the serial port with the time anchor point to complete its own timing, then adjusts the message transmission delay to align the rising edge of the transmission signal at the whole second with the rising edge of the aligned 1PPS pulse-per-second signal, and broadcasts the timing information to the pseudolite slave station via a message; The pseudolite slave station receives the message broadcast by the pseudolite master station, captures, tracks, performs frame synchronization, and performs message decoding on the message to determine time information, latches the message reception time in real time, and calculates its own transmission time based on the reception time. When the reception time reaches the designated transmission time set by the software, when the pseudolite master station transmits a new frame of message, the pseudolite slave station transmits its first frame of message at the same time, thereby completing time synchronization with the pseudolite master station and achieving time synchronization between the ground-based pseudolite system and the BeiDou satellite navigation system.

2. The method according to claim 1, characterized in that The transmission time of the Beidou satellite signal calculated by the pseudolite master station is at nanosecond level accuracy.

3. The method according to claim 2, characterized in that When the pseudo-satellite master station calculates the local reception time, factors considered also include: satellite clock error, ionospheric delay and tropospheric delay.

4. The method according to claim 3, characterized in that The pseudo-satellite master station adjusts the message transmission delay, including: the pseudo-satellite master station latches the number of remaining to-be-sent bits in the message FIFO at the time the aligned 1PPS second pulse signal is input, and correspondingly splices and fills the message bits to ensure that the rising edge of the first bit of the message carrying the timing information is aligned with the rising edge of the aligned 1PPS second pulse signal.

5. The method according to any one of claims 1 to 4, characterized in that The message transmitted by the pseudo-satellite master station is a 1ms / 10ms time slot signal, the ratio of effective time slot to time slot is 1:10, the number of code cycles within the message bit is 1, and the number of bits within the frame is 300.

6. The method according to claim 5, characterized in that The method further comprises: After receiving the local reception time through the serial port, the pseudolite master station calculates the time of transmitting the first bit of the timing message and uses the time to update the timing information; The pseudolite slave station decodes the message to obtain time information, specifically including decoding the seconds of the week of the current message frame.

7. A ground-based pseudo-satellite system, characterized in that: The system comprises: The pseudolite master station is configured to receive Beidou satellite signals through its built-in Beidou satellite receiving module, capture, track, frame synchronize, and perform message decoding on the Beidou satellite signals, decode the transmission time and signal transmission delay of the Beidou satellite signals, adjust the local clock model based on the transmission time and signal transmission delay, and calculate the local reception time; The pseudolite master station is used to correct the 1PPS pulse-second signal after completing the local time calibration, so that the rising edge of the corrected 1PPS pulse-second signal is aligned with the whole second of the local receiving time, and output the aligned 1PPS pulse-second signal; The pseudolite master station is configured to use the aligned 1PPS pulse-per-second signal as a time anchor point, match the local reception time received through the serial port with the time anchor point to complete its own timing, then adjust the telegram transmission delay to align the rising edge of the transmission signal at the whole second with the rising edge of the aligned 1PPS pulse-per-second signal, and broadcast timing information to the pseudolite slave stations via telegrams; The pseudolite slave station is configured to receive the message broadcast by the pseudolite master station, capture, track, frame synchronize, and perform message decoding on the message to determine time information, latch the message reception time in real time, and calculate its own transmission time based on the reception time. When the reception time reaches the designated transmission time set by the software, when the pseudolite master station transmits a new frame of message, the pseudolite slave station transmits its first frame of message at the same time, thereby completing time synchronization with the pseudolite master station and achieving time synchronization between the ground-based pseudolite system and the BeiDou satellite navigation system.

8. An electronic device, characterized in that: include: memory for storing computer programs; A processor is configured to implement the steps of the high-precision clock synchronization method based on Beidou satellite navigation as described in any one of claims 1 to 6 when executing the computer program.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the steps of the high-precision clock synchronization method based on Beidou satellite navigation are implemented as described in any one of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the high-precision clock synchronization method based on Beidou satellite navigation are implemented as described in any one of claims 1 to 6.

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