A method and system for anti-interference centerless time synchronization of multiple pseudo-satellite base stations

Abstract

The present invention discloses an interference-resistant method and system for centerless time synchronization of multiple pseudo-satellite base stations, the method comprising: initializing the priorities of all pseudo-satellite base stations; calculating the delay time between the pseudo-satellite base station of the first priority and the pseudo-satellite base stations of other priorities; the pseudo-satellite base station of the first priority sends a timestamp and a delay time to the pseudo-satellite base stations of other priorities, and calculates the clock difference in combination with the timestamp of the pseudo-satellite base stations of other priorities; the pseudo-satellite base stations of other priorities publish the calculated clock difference to the pseudo-satellite base station of the first priority to complete the initial time synchronization; all pseudo-satellite base stations perform secondary time synchronization correction, and repeat the time synchronization process to the pseudo-satellite base stations that still have clock differences. The present invention adopts the idea of ​​grading, primary time synchronization calibration, secondary time synchronization correction, improves the accuracy of time synchronization, performs time synchronization fault diagnosis according to the priority of each pseudo-satellite base station, and effectively improves the robustness of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of pseudo-satellite base station time synchronization, and in particular to an interference-resistant centerless time synchronization method and system for multiple pseudo-satellite base stations. Background Art

[0002] Pseudolite is a ground navigation signal transmitting device used to support and enhance the service capabilities of space satellite navigation systems. It can solve the problems of insufficient visible navigation satellites, poor geometric composition, low signal level, etc. caused by the influence of geographical environment, which make it impossible to achieve continuous seamless navigation positioning and low positioning accuracy. In order to realize information exchange between multiple pseudo-satellite base stations, time synchronization between pseudo-satellite base stations is a technical problem that needs to be solved urgently.

[0003] In multiple pseudo-satellite systems, in order to ensure the reliability of navigation positioning and task completion, it is necessary to quickly and accurately complete the time synchronization of multiple pseudo-satellite base stations. Due to the complexity and uncertainty of the environment, timely and accurate time synchronization of multiple pseudo-satellite base stations has become a key problem that needs to be solved in pseudo-satellite system applications. Although methods such as a zero-baseline self-closed-loop satellite-to-ground time synchronization method in a pseudo-satellite positioning system, an indoor pseudo-satellite self-closed-loop time synchronization method, and a base station synchronization, positioning method and device have been proposed, these time synchronization methods are often centered on a main base station, and inevitably have problems such as weak anti-interference and fault tolerance, low computational efficiency and accuracy, and therefore need to be improved. Summary of the invention

[0004] The present invention provides an interference-resistant method and system for centerless time synchronization of multiple pseudo-satellite base stations, so as to solve the technical problems that the current multiple pseudo-satellite base stations have weak interference-resistant capabilities and low calculation efficiency.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] On the one hand, the present invention provides an interference-resistant method for synchronizing multiple pseudo-satellite base stations without a center, and the interference-resistant method for synchronizing multiple pseudo-satellite base stations without a center includes:

[0007] S1: Initialize the priority of all pseudo-satellite base stations;

[0008] S2: The pseudo-satellite base station with the first priority sends a detection signal, and the delay time between the pseudo-satellite base station with the first priority and the pseudo-satellite base stations with other priorities is calculated;

[0009] S3: The pseudo-satellite base station of the first priority sends a timestamp and a delay time to pseudo-satellite base stations of other priorities, and calculates a clock difference in combination with the timestamps of the pseudo-satellite base stations of other priorities;

[0010] S4: The pseudo-satellite base stations of other priorities publish the calculated clock difference to the pseudo-satellite base station of the first priority, and use the clock difference to update the timestamp of the current time of each pseudo-satellite base station, completing the initial time synchronization;

[0011] S5: All pseudo-satellite base stations perform secondary time synchronization correction, and repeat the time synchronization process for pseudo-satellite base stations that still have clock errors;

[0012] S6: Reset the priority of the pseudo-satellite base station according to the clock difference in the previous correction cycle, correct the time of the pseudo-satellite base station with the first priority, and diagnose the time synchronization failure.

[0013] Furthermore, the initialization of all pseudo-satellite base station priorities in step S1 includes the following steps:

[0014] Initializing the priorities of the pseudo-satellite base stations and determining a pseudo-satellite base station with a first priority;

[0015] Initialize the correction period and time synchronization interval period;

[0016] Time synchronization is completed within the correction period.

[0017] Furthermore, in step S2, the pseudo-satellite base station with the first priority sends a detection signal, and the delay time between the pseudo-satellite base station with the first priority and pseudo-satellite base stations with other priorities is calculated, including the following steps:

[0018] During the correction period, the pseudo-satellite base station with the first priority sends a detection signal to the pseudo-satellite base stations with other priorities. The return time of the detection signal is T = {T2, ..., T n}, calculate the delay time τ between the pseudo-satellite base station of the first priority and the pseudo-satellite base stations of other priorities = {τ2,...,τ n}, n is the priority number of the pseudo-satellite base station, and τ=T / 2.

[0019] Furthermore, in step S3, the pseudo-satellite base station of the first priority sends a timestamp and a delay time to pseudo-satellite base stations of other priorities, and the clock difference is calculated by combining the above information with the timestamps of the pseudo-satellite base stations of other priorities, including the following steps:

[0020] The pseudo-satellite base station of the first priority sends the pseudo-satellite base station timestamp t1 and delay time τ of the first priority to the pseudo-satellite base stations of other priorities;

[0021] The pseudo-satellite base station of other priorities has its own timestamp t={t2,...,t n}, the first priority pseudo-satellite base station timestamp t1 and delay time τ, calculate the clock difference t z , the t z={tz2,...,t zn};

[0022] The calculation formula of the pseudo-satellite base station clock error of the second priority is as follows:

[0023] t z2 =t1+τ2-t2

[0024] Among them, t z2 Indicates the pseudo-satellite base station clock error of the second priority.

[0025] Furthermore, in step S4, the pseudo-satellite base stations of other priorities publish the calculated clock difference to the pseudo-satellite base station of the first priority, and the timestamps of the current time of the respective pseudo-satellite base stations are updated by the clock difference to complete the initial time synchronization, including the following steps:

[0026] Other priority pseudo-satellite base stations publish their respective clock differences to the first priority pseudo-satellite base station;

[0027] Other priority pseudo-satellite base stations use the clock difference to update the timestamp of the current time of their respective pseudo-satellite base stations to complete the initial time synchronization. The specific calculation formula is shown in the following formula:

[0028] t dn ′=t dn +t zn

[0029] Among them, t dn Indicates the timestamp of the pseudo-satellite base station with priority n at the current time, d indicates the current time, t dn ' represents the timestamp of the pseudo-satellite base station with priority n at the current time after completing the initial time synchronization;

[0030] The pseudolite base stations of other priorities publish the updated timestamps to the pseudolite base station of the first priority.

[0031] Furthermore, in step S5, all pseudo-satellite base stations perform secondary time synchronization correction, and repeat the time synchronization process for pseudo-satellite base stations that still have clock errors, including the following steps:

[0032] Compare the timestamp of the pseudo-satellite base station of the first priority with the timestamps of the pseudo-satellite base stations of other priorities that have undergone initial time synchronization and their respective delay times;

[0033] If there is still a clock error, repeat steps S2-S5.

[0034] Furthermore, the step S6 resets the pseudo-satellite base station priority according to the clock difference in the previous correction cycle, corrects the pseudo-satellite base station time of the first priority, and diagnoses the time synchronization failure, including the following steps:

[0035] Reset the priority of pseudo-satellite base stations according to the clock error in the previous correction cycle;

[0036] For newly added pseudo-satellite base stations, the priority is arranged from high to low in the order of joining;

[0037] Correct the pseudo-satellite base station time of the first priority by using the GNSS time information;

[0038] If the pseudo-satellite base station of the first priority fails or cannot receive information from pseudo-satellite base stations of other priorities, the pseudo-satellite base station of the second priority is used as a reference to complete the time synchronization process.

[0039] On the other hand, the present invention also provides an interference-resistant multiple pseudo-satellite base station centerless time synchronization system, the interference-resistant multiple pseudo-satellite base station centerless time synchronization system comprising:

[0040] Initialization module: initializes the priority, correction cycle and time synchronization interval of all pseudo-satellite base stations;

[0041] Information detection module: The pseudo-satellite base station with the first priority sends a detection signal, and calculates the delay time between the pseudo-satellite base station with the first priority and the pseudo-satellite base stations with other priorities;

[0042] Time synchronization module: The pseudo-satellite base station with the first priority sends the timestamp and delay time to the pseudo-satellite base stations with other priorities, and calculates the clock difference in combination with the timestamps of the pseudo-satellite base stations with other priorities; the pseudo-satellite base stations with other priorities publish the calculated clock difference to the pseudo-satellite base station with the first priority, and the timestamp of the current moment of each pseudo-satellite base station is updated by the clock difference to complete the initial time synchronization; all pseudo-satellite base stations perform secondary time synchronization correction and repeat the time synchronization process for the pseudo-satellite base stations that still have clock differences;

[0043] Correction and fault diagnosis module: reset the priority of pseudo-satellite base stations according to the clock difference in the previous correction cycle. For newly added pseudo-satellite base stations, the priority is arranged from high to low in the order of joining. The time of the pseudo-satellite base station with the first priority is corrected, and time synchronization faults are diagnosed.

[0044] The beneficial effects brought about by the technical solution provided by the present invention include at least:

[0045] 1. The present invention introduces the idea of ​​decentralization to set the priority of each pseudo-satellite base station, which can avoid the systemic risk caused by the failure of the first priority. At the same time, the priority of each pseudo-satellite base station is updated according to the clock difference of the previous correction cycle, eliminating the subjective uncertainty brought by the fixed priority, and improving the system's ability to resist failures. Compared with the time synchronization process performed by the central base station, the present invention has stronger anti-interference and anti-risk capabilities;

[0046] 2. The present invention sets a correction cycle and a time synchronization interval cycle, and performs time synchronization in each correction cycle. On the one hand, it can detect newly added pseudo-satellite base stations to improve the scalability of the system, and on the other hand, it can avoid the collapse of the system caused by the failure of a certain pseudo-satellite base station. The correction cycle and the time synchronization interval cycle are separated, and the correction of the priority and time stamp of each pseudo-satellite base station is completed only in the correction cycle. Compared with the method of performing time synchronization and time correction at the same time, this scheme can not only reduce the amount of calculation for frequent time correction of each pseudo-satellite base station, but also further reduce the hardware and maintenance costs. Therefore, the method and system can bring higher economic benefits and have better economic potential;

[0047] 3. The present invention adopts a hierarchical concept. The initial time synchronization completes the calibration of the time of each pseudo-satellite base station. After the initial time synchronization, a secondary time synchronization correction is performed for each pseudo-satellite base station that still has a clock error. Compared with the time synchronization scheme that only performs one time synchronization, this scheme completes multiple corrections in a short time, avoiding errors caused by instantaneous faults of each pseudo-satellite base station, and effectively improving the accuracy of time synchronization. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0049] Figure 1 A diagram of the steps of implementing a method for anti-interference, centerless time synchronization of multiple pseudo-satellite base stations provided by an embodiment of the present invention;

[0050] Figure 2 A schematic diagram of a module of an interference-resistant multiple pseudo-satellite base station centerless time synchronization system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0051] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0052] Embodiment 1

[0053] This embodiment will describe in more detail a method for synchronizing multiple pseudo-satellite base stations without a center for interference according to the present invention in conjunction with the corresponding drawings. Figure 1As shown, the method is mainly divided into six steps. The first step is to initialize the priorities of all pseudo-satellite base stations. The second step is that the pseudo-satellite base station with the first priority sends a detection signal and calculates the delay time between the pseudo-satellite base station with the first priority and the pseudo-satellite base stations with other priorities. The third step is that the pseudo-satellite base station with the first priority sends a timestamp and a delay time to pseudo-satellite base stations with other priorities, and calculates the clock difference in combination with the timestamps of the pseudo-satellite base stations with other priorities. The fourth step is that the pseudo-satellite base stations with other priorities publish the calculated clock difference to the pseudo-satellite base station with the first priority, and the timestamps of the current pseudo-satellite base stations are updated by the clock difference to complete the initial time synchronization. The fifth step is that all pseudo-satellite base stations perform secondary time synchronization correction and repeat the time synchronization process for the pseudo-satellite base stations that still have a clock difference. The sixth step is to reset the priority of the pseudo-satellite base station based on the clock difference in the previous correction cycle, correct the time of the pseudo-satellite base station with the first priority, and diagnose the time synchronization failure.

[0054] Specifically, the method of this embodiment includes the following steps:

[0055] Step S1: Initialize the priorities of all pseudo-satellite base stations.

[0056] Initializing the priority of each pseudo-satellite base station and determining a pseudo-satellite base station with a first priority, wherein the reason for the initialization may be set by the status of each pseudo-satellite base station or may be set due to human factors;

[0057] Initialize the correction period and time synchronization interval period;

[0058] The entire time is divided into two parts, a correction period and a time synchronization interval period. Time synchronization is completed within the correction period, and the other time is the time synchronization interval period. In actual settings, the time synchronization interval period can be 60-100 times the correction period.

[0059] Step S2: The pseudo-satellite base station of the first priority sends a detection signal, and the delay time between the pseudo-satellite base station of the first priority and pseudo-satellite base stations of other priorities is calculated.

[0060] During the correction period, the pseudo-satellite base station with the first priority sends a detection signal to the pseudo-satellite base stations with other priorities. The return time of the detection signal is T = {T2, ..., T n}, calculate the delay time τ between pseudo-satellite base stations of other priorities = {τ2,...,τ n}, n is the priority number of the pseudo-satellite base station, and τ=T / 2.

[0061] Step S3: The pseudo-satellite base station of the first priority sends a timestamp and a delay time to pseudo-satellite base stations of other priorities, and calculates a clock difference in combination with the timestamps of the pseudo-satellite base stations of other priorities.

[0062] The pseudo-satellite base station of the first priority sends the pseudo-satellite base station timestamp t1 and delay time τ of the first priority to the pseudo-satellite base stations of other priorities;

[0063] The pseudo-satellite base station of other priorities has its own timestamp t={t2,...,t n}, the first priority pseudo-satellite base station timestamp t1 and delay time τ, calculate the clock difference t z , the t z ={t z2 ,...,t zn};

[0064] The calculation formula of the pseudo-satellite base station clock error of the second priority is as follows:

[0065] t z2 =t1+τ2-t2

[0066] Among them, t z2 Indicates the pseudo-satellite base station clock error of the second priority.

[0067] Step S4: the pseudo-satellite base stations of other priorities publish the calculated clock differences to the pseudo-satellite base station of the first priority, and use the clock differences to update the timestamps of the current times of the respective pseudo-satellite base stations, thus completing the initial time synchronization.

[0068] Other priority pseudo-satellite base stations publish their respective clock differences to the first priority pseudo-satellite base station;

[0069] Other priority pseudo-satellite base stations use the clock difference to update the timestamp of the current time of their respective pseudo-satellite base stations to complete the initial time synchronization. The specific calculation formula is shown in the following formula:

[0070] t dn ′=t dn +t zn

[0071] Among them, t dn Indicates the timestamp of the pseudo-satellite base station with priority n at the current time, d indicates the current time, t dn ' represents the timestamp of the pseudo-satellite base station with priority n at the current time after completing the initial time synchronization;

[0072] The pseudolite base stations of other priorities publish the updated timestamps to the pseudolite base station of the first priority.

[0073] Step S5: All pseudo-satellite base stations perform secondary time synchronization correction, and repeat the time synchronization process for pseudo-satellite base stations that still have clock errors.

[0074] Compare the timestamp of the pseudo-satellite base station of the first priority with the timestamps of the pseudo-satellite base stations of other priorities that have undergone initial time synchronization and their respective delay times;

[0075] If there is still a clock error, repeat steps S2-S5.

[0076] Step S6: Reset the priority of the pseudolite base stations according to the clock difference in the previous correction cycle, correct the time of the pseudolite base station with the first priority, and diagnose the time synchronization failure.

[0077] Reset the priority of pseudo-satellite base stations according to the clock error in the previous correction cycle;

[0078] For newly added pseudo-satellite base stations, the priority is arranged from high to low in the order of joining;

[0079] Correct the pseudo-satellite base station time of the first priority by using the GNSS time information;

[0080] If the pseudo-satellite base station of the first priority fails or cannot receive information from pseudo-satellite base stations of other priorities, the pseudo-satellite base station of the second priority is used as a reference to complete the time synchronization process.

[0081] In summary, the present invention makes up for the defect of the traditional method of taking the main base station as the center for time synchronization. By setting the priority of each pseudo-satellite base station, on the one hand, the overall anti-interference ability of the system is improved, and on the other hand, decentralization is completed to reduce the risk of system crash in the face of failures. The method adopts the idea of ​​hierarchical fusion. First, the first-priority pseudo-satellite base station transmits a detection signal to obtain the delay time, which is calibrated through the initial time synchronization and corrected through the secondary time synchronization. The pseudo-satellite base stations that fail to complete the time synchronization are continuously corrected. This not only improves the accuracy of time synchronization, but also avoids the error caused by the primary time synchronization, thereby improving the overall robustness of the method.

[0082] Embodiment 2

[0083] This embodiment provides an interference-resistant multiple pseudo-satellite base station centerless time synchronization system. The main modules of the interference-resistant multiple pseudo-satellite base station centerless time synchronization system are as follows: Figure 2 As shown:

[0084] Initialization module: initializes the priority, correction cycle and time synchronization interval of all pseudo-satellite base stations;

[0085] Information detection module: The pseudo-satellite base station with the first priority sends a detection signal, and calculates the delay time between the pseudo-satellite base station with the first priority and the pseudo-satellite base stations with other priorities;

[0086] Time synchronization module: The pseudo-satellite base station with the first priority sends the timestamp and delay time to the pseudo-satellite base stations with other priorities, and calculates the clock difference in combination with the timestamps of the pseudo-satellite base stations with other priorities; the pseudo-satellite base stations with other priorities publish the calculated clock difference to the pseudo-satellite base station with the first priority, and the timestamp of the current moment of each pseudo-satellite base station is updated by the clock difference to complete the initial time synchronization; all pseudo-satellite base stations perform secondary time synchronization correction and repeat the time synchronization process for the pseudo-satellite base stations that still have clock differences;

[0087] Correction and fault diagnosis module: reset the priority of pseudo-satellite base stations according to the clock difference in the previous correction cycle. For newly added pseudo-satellite base stations, the priority is arranged from high to low in the order of joining. The time of the pseudo-satellite base station with the first priority is corrected, and time synchronization faults are diagnosed.

[0088] The anti-interference multiple pseudo-satellite base station centerless time synchronization system of the present embodiment corresponds to the anti-interference multiple pseudo-satellite base station centerless time synchronization method of the above-mentioned embodiment; wherein, the functions implemented by each functional module in the anti-interference multiple pseudo-satellite base station centerless time synchronization system of the present embodiment correspond one-to-one to each process step in the anti-interference multiple pseudo-satellite base station centerless time synchronization method of the above-mentioned embodiment; therefore, they will not be repeated here.

Claims

1. An anti-interference method for centerless time synchronization of multiple pseudo-satellite base stations, characterized in that: The following steps are involved: S1: Initialize the priority of all pseudo-satellite base stations; S2: The pseudo-satellite base station with the first priority sends a detection signal, and the delay time between the pseudo-satellite base station with the first priority and the pseudo-satellite base stations with other priorities is calculated; S3: The pseudo-satellite base station of the first priority sends a timestamp and a delay time to pseudo-satellite base stations of other priorities, and calculates a clock difference in combination with the timestamps of the pseudo-satellite base stations of other priorities; S4: The pseudo-satellite base stations of other priorities publish the calculated clock difference to the pseudo-satellite base station of the first priority, and use the clock difference to update the timestamp of the current time of each pseudo-satellite base station, completing the initial time synchronization; S5: All pseudo-satellite base stations perform secondary time synchronization correction, and repeat the time synchronization process for pseudo-satellite base stations that still have clock errors; S6: Reset the priority of the pseudo-satellite base station according to the clock difference in the previous correction cycle, correct the time of the pseudo-satellite base station with the first priority, and diagnose the time synchronization failure; The time synchronization fault diagnosis includes the following steps: if the pseudo-satellite base station of the first priority fails or cannot receive information of pseudo-satellite base stations of other priorities, the pseudo-satellite base station of the second priority is used as a reference to complete the time synchronization process.

2. The anti-interference method for centerless time synchronization of multiple pseudo-satellite base stations according to claim 1, characterized in that: Initializing the priorities of all pseudo-satellite base stations in step S1 includes the following steps: Initializing the priorities of the pseudo-satellite base stations and determining a pseudo-satellite base station with a first priority; Initialize the correction period and time synchronization interval period; Time synchronization is completed within the correction period.

3. The anti-interference method for centerless time synchronization of multiple pseudo-satellite base stations according to claim 1, characterized in that: In step S2, the pseudo-satellite base station with the first priority sends a detection signal, and the delay time between the pseudo-satellite base station with the first priority and other pseudo-satellite base stations with other priorities is calculated, including the following steps: During the correction period, the pseudo-satellite base station with the first priority sends a detection signal to the pseudo-satellite base stations with other priorities. , calculate the delay time between the pseudo-satellite base station of the first priority and the pseudo-satellite base stations of other priorities , where n is the priority number of the pseudo-satellite base station, .

4. The anti-interference method for centerless time synchronization of multiple pseudo-satellite base stations as claimed in claim 3, characterized in that: In step S3, the pseudo-satellite base station with the first priority sends a timestamp and a delay time to pseudo-satellite base stations with other priorities, and the clock difference is calculated by combining the above information with the timestamps of the pseudo-satellite base stations with other priorities, including the following steps: The pseudo-satellite base station with the first priority sends the pseudo-satellite base station timestamp of the first priority to the pseudo-satellite base stations with other priorities. and delay time ; The pseudo-satellite base station of other priority levels has its own timestamp , the first priority pseudo-satellite base station timestamp and delay time , calculate the clock difference , ; The calculation formula of the pseudo-satellite base station clock error of the second priority is as follows: ； in, Indicates the pseudo-satellite base station clock error of the second priority.

5. The anti-interference method for centerless time synchronization of multiple pseudo-satellite base stations as claimed in claim 4, characterized in that: In step S4, the pseudo-satellite base stations of other priorities publish the calculated clock difference to the pseudo-satellite base station of the first priority, and the timestamps of the current time of the respective pseudo-satellite base stations are updated by the clock difference to complete the initial time synchronization, including the following steps: Other priority pseudo-satellite base stations publish their respective clock differences to the first priority pseudo-satellite base station; Other priority pseudo-satellite base stations use the clock difference to update the timestamp of the current time of their respective pseudo-satellite base stations to complete the initial time synchronization. The specific calculation formula is shown in the following formula: ； in, Indicates the timestamp of the pseudo-satellite base station with priority n at the current time, d indicates the current time, Indicates the timestamp at the current time when the pseudo-satellite base station with priority n completes the initial time synchronization; The pseudolite base stations of other priorities publish the updated timestamps to the pseudolite base station of the first priority.

6. The anti-interference method for centerless time synchronization of multiple pseudo-satellite base stations according to claim 1, characterized in that: In step S5, all pseudo-satellite base stations perform secondary time synchronization correction, and repeat the time synchronization process for pseudo-satellite base stations that still have clock errors, including the following steps: Compare the timestamp of the pseudo-satellite base station of the first priority with the timestamps of the pseudo-satellite base stations of other priorities that have undergone initial time synchronization and their respective delay times; If there is still a clock error, repeat steps S2-S5.

7. The anti-interference method for centerless time synchronization of multiple pseudo-satellite base stations according to claim 1, characterized in that: The step S6 resets the pseudolite base station priority according to the clock difference in the previous correction cycle, and corrects the pseudolite base station time of the first priority, including the following steps: Reset the priority of pseudo-satellite base stations according to the clock error in the previous correction cycle; For newly added pseudo-satellite base stations, the priority is arranged from high to low in the order of joining; The time of the pseudo-satellite base station with the first priority is corrected by the GNSS time information.

8. An anti-interference multiple pseudo-satellite base station centerless time synchronization system, characterized in that: include: Initialization module: initializes the priority, correction cycle and time synchronization interval of all pseudo-satellite base stations; Information detection module: The pseudo-satellite base station with the first priority sends a detection signal, and calculates the delay time between the pseudo-satellite base station with the first priority and the pseudo-satellite base stations with other priorities; Time synchronization module: The pseudo-satellite base station with the first priority sends the timestamp and delay time to the pseudo-satellite base stations with other priorities, and calculates the clock difference in combination with the timestamps of the pseudo-satellite base stations with other priorities; Other priority pseudo-satellite base stations publish the calculated clock difference to the first priority pseudo-satellite base station, and use the clock difference to update the current timestamp of each pseudo-satellite base station to complete the initial time synchronization; all pseudo-satellite base stations perform secondary time synchronization correction and repeat the time synchronization process for pseudo-satellite base stations that still have clock differences; Correction and fault diagnosis module: reset the priority of pseudo-satellite base stations according to the clock difference in the previous correction cycle. For newly added pseudo-satellite base stations, the priority is arranged from high to low in the order of joining. The time of the pseudo-satellite base station with the first priority is corrected to diagnose time synchronization failures. To implement an interference-resistant method for center-free time synchronization of multiple pseudo-satellite base stations as described in any one of claims 1-7.

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