Ship-based 5G clock synchronization system and method

Abstract

The invention discloses a ship-based 5G clock synchronization system and method, and belongs to the design of mobile communication networks, and the system at least comprises a main clock source, a standby clock source, a bearer network I, a bearer network II, a bearer network III, a 5G base station, and a 5G core network. The main clock source and the standby clock source are used for providing clock messages for a bearer network composed of the bearer network I, the bearer network II and the bearer network III, and the priority of the main clock source is higher than that of the standby clock source; the bearer network I, the bearer network II and the bearer network III are all in signal connection with the 5G core network and the 5G base station; the main clock source, the standby clock source and the 5G base station are common clock nodes; the bearer network I, the bearer network I and the bearer network III are boundary clock nodes; the main clock source and the standby clock source are both 1588V2 clocks. Therefore, frequency synchronization and time synchronization can be provided at the same time, the main clock source and the standby clock source are provided, and the technical problems of potential safety hazards, poor survivability and the like in a current ship-borne scene are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of mobile communication network design, and specifically relates to a shipborne 5G clock synchronization system and method. Background Art

[0002] As 5G technology becomes increasingly mature, the three major 5G application scenarios of enhanced mobile bandwidth (eMBB), ultra-reliable low-latency communications (uRLLC) and massive machine-type communications (mMTC) have been widely used in thousands of industries, and 5G application opportunities will also be ushered in in shipborne scenarios.

[0003] 5G network deployment and service activation require synchronization support, including frequency synchronization and time synchronization. If there is a problem with synchronization, the success rate of network device switching will be reduced, affecting service perception, or even the 5G network system will not be able to operate. At present, there are five main time synchronization methods in shipborne scenarios: B (DC) code timing, network timing, asynchronous serial port timing, NTP timing and GPS timing (Beidou timing), but they face the following key problems:

[0004] a) B (DC) code / network timing: In order to meet the needs of diverse application services, 5G networks require frequency synchronization and time synchronization support. Frequency synchronization is to achieve better time synchronization performance. The frequency synchronization deviation is required to be no more than 0.05ppm, and the time synchronization deviation is generally required to be ±1.5us. Special application scenarios even require nanoseconds. However, the shipboard B code and network timing methods only provide time (phase) synchronization, not frequency synchronization. At the same time, the current mature commercial 5G network equipment is different from the shipboard time system interface type and cannot be directly connected;

[0005] b) Asynchronous serial timing: The time code is still in B code mode, and the transmission mode is asynchronous transmission, which is not suitable for 5G system clock synchronization;

[0006] c) NTP timing: It provides millisecond-level synchronization accuracy and is mainly used in scenarios with low accuracy requirements. It does not meet the microsecond or even nanosecond synchronization requirements of 5G.

[0007] d) GPS / Beidou timing: In shipborne environments, a large number of 5G base stations are required, and there are many baseband processing units (BBUs) deployed in cabins in different partitions of the ship. If GPS or Beidou is used directly to provide the clock source, clock cables need to be deployed to base stations in different partitions, which makes deployment difficult. Too long clock cables will also introduce excessive time delays. At the same time, GPS is controlled by the United States, and synchronization also poses security risks.

[0008] In addition, the shipborne environment has high requirements for network system anti-destruction, and clock synchronization is crucial to network operation. Therefore, the 5G system clock synchronization in the shipborne scenario needs to provide a complete protection mechanism on the basis of meeting the clock synchronization requirements to meet the high anti-destruction requirements. Summary of the invention

[0009] In view of this, the present invention provides a shipborne 5G clock synchronization system and method, which solves the technical problems of low accuracy, potential safety hazards and poor anti-destruction performance of clock synchronization in current shipborne scenarios.

[0010] The shipborne 5G clock synchronization system adopts the following technical solutions:

[0011] A shipborne 5G clock synchronization system, comprising at least a main clock source, a backup clock source, a bearer network I, a bearer network II, a bearer network III, a 5G base station, and a 5G core network;

[0012] The master clock source and the backup clock source are used to provide clock messages to the bearer network composed of the bearer network I, the bearer network II and the bearer network III, and the priority of the master clock source is higher than that of the backup clock source;

[0013] The bearer network I, the bearer network II and the bearer network III are all connected to the 5G core network and the 5G base station signal;

[0014] The main clock source, the backup clock source and the 5G base station are common clock nodes;

[0015] The bearer network I, the bearer network I and the bearer network III are boundary clock nodes;

[0016] The main clock source and the backup clock source are both 1588V2 clocks.

[0017] Furthermore, the main clock source and the backup clock source are deployed in cabins of different partitions on the ship.

[0018] The shipborne 5G clock synchronization method adopts the following technical solutions:

[0019] The clock tracking relationship performed under normal circumstances is: the bearer network II tracks the main clock source, the bearer network III tracks the bearer network II, and the bearer network I tracks the bearer network III;

[0020] When any node device or the link between any two nodes of the shipborne 5G clock synchronization system fails, the clock tracking relationship under the clock link protection condition is executed: the bearer network II tracks the main clock source, the bearer network III and the bearer network I respectively, and in the clock link, the priority of the clock link between the bearer network II and the main clock source is priority one, the priority of the clock link between the bearer network II and the bearer network III is priority two, and the priority of the clock link between the bearer network II and the bearer network I is priority three; the bearer network III tracks the bearer network II and the bearer network I respectively, and in the clock link, the priority of the clock link between the bearer network III and the bearer network II is priority one, and the priority of the clock link between the bearer network III and the bearer network I is priority two; the bearer network I tracks the bearer network III and the backup clock source respectively, and in the clock link, the priority of the clock link between the bearer network I and the bearer network III is priority one, and the priority of the clock link between the bearer network I and the backup clock source is priority two.

[0021] Furthermore, when the clock link and / or the main clock source between the bearer network II and the main clock source fails, the node device first keeps the internal oscillator of its own device in free oscillation and starts the timer at the same time. After the timer reaches the set duration, if the clock link and / or the main clock source between the bearer network II and the main clock source fails, the clock tracking relationship under normal circumstances continues to be executed; otherwise, the clock tracking relationship under clock link protection is executed.

[0022] Furthermore, when the shipborne 5G clock synchronization system is executing the clock tracking relationship under the clock link protection condition:

[0023] If the clock link between the bearer network II and the main clock source and / or the main clock source failure is restored and the node device can detect the clock message of the main clock source, the timer is started at the same time. After the timer reaches the set duration, if the node device can still detect the clock message of the main clock source, the clock tracking relationship under normal circumstances is executed.

[0024] Furthermore, if the node device fails to detect the clock message of the clock source after the timer reaches the set duration, the clock tracking relationship under the clock link protection condition is still maintained.

[0025] Beneficial effects:

[0026] 1. The shipborne 5G clock synchronization system deploys 1588V2 clock as the main clock source and backup clock source. The main clock source, backup clock source and 5G base station are common clock nodes; Bearer Network I, Bearer Network I and Bearer Network III are boundary clock nodes. In this way, a packet switching network is formed, which is easy to achieve synchronization on the IP network, and can achieve sub-microsecond synchronization accuracy. It can provide frequency synchronization and time synchronization at the same time, meet the requirements of 5G high-precision clock synchronization in the shipborne environment, and have a main clock source and a backup clock source, solving the technical problems of low accuracy, safety hazards and poor anti-destruction performance of clock synchronization in the current shipborne scenario.

[0027] 2. The main clock source and the backup clock source are deployed in cabins of different partitions on the ship. This improves the safety and reliability of the clock synchronization system in the shipboard environment and has a higher anti-destruction capability.

[0028] 3. The clock tracking relationship under normal circumstances is: bearer network II tracks the main clock source, bearer network III tracks bearer network II, and bearer network I tracks bearer network III; when any node device or the link between any two nodes of the shipborne 5G clock synchronization system fails, the clock tracking relationship under the clock link protection situation is: bearer network II tracks the main clock source, bearer network III and bearer network I respectively, and in this clock link, the priority of the clock link between bearer network II and the main clock source is priority one, the priority of the clock link between bearer network II and bearer network III is priority two, and the priority of the clock link between bearer network II and bearer network I is priority three; bearer network III tracks bearer network II and bearer network I respectively, and in this clock link, the priority of the clock link between bearer network III and bearer network II is priority one, and the priority of the clock link between bearer network III and bearer network I is priority two; bearer network I tracks bearer network III and the backup clock source respectively, and in this clock link, the priority of the clock link between bearer network I and bearer network III is priority one, and the priority of the clock link between bearer network I and the backup clock source is priority two.

[0029] In this way, if any node device (clock source or bearer network) or any link transmission failure between two nodes occurs, the clock tracking and switching can be automatically completed to ensure the normal clock synchronization of the ship's 5G system and high anti-destruction performance.

[0030] 4. When the clock link and / or main clock source between bearer network II and the main clock source fails, each node device first keeps the internal oscillator of its own device in free oscillation and starts the timer at the same time. After the timer reaches the set duration, if the clock link and / or main clock source between bearer network II and the main clock source fails, the clock tracking relationship under normal circumstances will continue to be executed. Otherwise, the clock tracking relationship under clock link protection will be executed.

[0031] In this way, because the shipboard power supply is unstable in the shipboard environment, the main clock source may lose power and restart instantly, so the switching mechanism of the main clock source and the backup clock source avoids the immediate switching of the main clock source to the backup clock source in this case, reducing the waste of resources caused by frequent switching between the main clock source and the backup clock source.

[0032] 5. When the shipborne 5G clock synchronization system is executing the clock tracking relationship under the clock link protection condition, if the clock link and / or the main clock source failure between the bearer network II and the main clock source is restored and the node device can detect the clock message of the main clock source, the timer is started at the same time. If the node device can still detect the clock message of the main clock source after the timer reaches the set duration, the clock tracking relationship under normal circumstances is executed.

[0033] In this way, under normal circumstances, the main clock source will give priority to providing clock synchronization services for the entire shipborne 5G system. Moreover, it is not immediately switched to the main clock source after the clock link failure between the bearer network II and the main clock source is restored. This avoids frequent restarts of the main clock source, which leads to frequent switching of the main clock source and the backup clock source. This facilitates the maintenance of the entire shipborne 5G system and reduces the waste of resources caused by frequent switching between the main clock source and the backup clock source. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The overall clock tracking relationship of the shipborne 5G clock synchronization system provided by the present invention;

[0035] Figure 2 The clock tracking relationship of the shipborne 5G clock synchronization system provided by the present invention under normal circumstances;

[0036] Figure 3 The clock tracking relationship under the link failure between the master clock source and the bearer network II or the master clock source failure in the shipborne 5G clock synchronization system provided by the present invention;

[0037] Figure 4 The clock tracking relationship under the link failure between the bearer network II and the carrier network III in the shipborne 5G clock synchronization system provided by the present invention;

[0038] Figure 5 The clock tracking relationship under the link failure between the bearer network I and the carrier network III in the shipborne 5G clock synchronization system provided by the present invention;

[0039] Figure 6 The clock tracking relationship under the link failure between the bearer network I and the carrier network III, and the link failure between the master clock source and the carrier network II in the shipborne 5G clock synchronization system provided by the present invention;

[0040] Figure 7The clock tracking relationship under the link failure between the bearer network II and the carrier network III, and the link failure between the main clock source and the carrier network II in the shipborne 5G clock synchronization system provided by the present invention. DETAILED DESCRIPTION

[0041] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0042] Embodiment 1:

[0043] This embodiment provides a shipborne 5G clock synchronization system, including a main clock source (time system 1), a backup clock source (time system 2), a bearer network I (bearer network 1), a bearer network II (bearer network 2), a bearer network III (bearer network 3), a 5G base station, and a 5G core network, wherein:

[0044] Both the master clock source and the backup clock source are 1588V2 clocks, which are used to provide high-precision clock messages for the bearer network composed of bearer network I, bearer network II and bearer network III, and the priority of the master clock source is higher than that of the backup clock source; bearer network I, bearer network II and bearer network III are all connected to the 5G core network and 5G base station signals; the master clock source, the backup clock source and the 5G base station are ordinary clock nodes, among which the master clock source and the backup clock source provide clock messages, and the 5G base station receives clock messages (clock signals); bearer network I, bearer network II and bearer network III are boundary clock nodes, which receive and terminate clock messages through the PTP port, and then regenerate PTP messages to transmit clock signals to other directions.

[0045] In this way, a packet switching network is formed, which can easily achieve synchronization on the IP network and achieve sub-microsecond synchronization accuracy. It can provide frequency synchronization and time synchronization at the same time, meet the requirements of 5G high-precision clock synchronization in shipborne environments, and have a main clock source and a backup clock source, solving the technical problems of low accuracy, safety hazards, and poor anti-destruction performance of clock synchronization in current shipborne scenarios.

[0046] More specifically, in this embodiment, the main clock source and the backup clock source are deployed in cabins of different partitions on the ship. This improves the safety and reliability of the clock synchronization system in the shipboard environment and has a higher anti-destruction capability.

[0047] Embodiment 2:

[0048] A shipborne 5G clock synchronization method is provided based on the first embodiment, referring to Figure 1 to Figure 7 , in which method:

[0049] The clock tracking relationship under normal circumstances is: bearer network II tracks the main clock source, bearer network III tracks bearer network II, and bearer network I tracks bearer network III;

[0050] When any node device or the link between any two nodes of the shipborne 5G clock synchronization system fails, the clock tracking relationship under the clock link protection condition is executed: bearer network II tracks the main clock source, bearer network III and bearer network I respectively, and in this clock link, the priority of the clock link between bearer network II and the main clock source is priority one, the priority of the clock link between bearer network II and bearer network III is priority two, and the priority of the clock link between bearer network II and bearer network I is priority three; bearer network III tracks bearer network II and bearer network I respectively, and in this clock link, the priority of the clock link between bearer network III and bearer network II is priority one, and the priority of the clock link between bearer network III and bearer network I is priority two; bearer network I tracks bearer network III and the backup clock source respectively, and in this clock link, the priority of the clock link between bearer network I and bearer network III is priority one, and the priority of the clock link between bearer network I and the backup clock source is priority two.

[0051] Because in a packet switching network, higher priority is executed before lower priority. According to the above clock tracking relationship, Figure 3 As shown in the figure, the clock tracking relationship when the link between the master clock source and bearer network II or the master clock source fails is: time system 2 → bearer network 1 → bearer network 3 → bearer network 2. The bearer network equipment transmits the clock signal to all the 5G base stations connected to it, realizing the clock synchronization between the base stations in the 5G system. Figure 4 As shown in the figure, the clock tracking relationship between bearer network II and bearer network III under link failure is: time system 1 → bearer network 2 and time system 2 → bearer network 1 → bearer network 3. The bearer network equipment transmits the clock signal to all the 5G base station equipment connected to it, realizing the clock synchronization between base stations in the 5G system. Figure 5 As shown in the figure, the clock tracking relationship between bearer network I and bearer network III under link failure is: time system 1 → bearer network 2 → bearer network 3 and time system 2 → bearer network 1. The bearer network equipment transmits the clock signal to all the 5G base stations connected to it, realizing clock synchronization between base stations in the 5G system. Figure 6 As shown in the figure, the clock tracking relationship when the link between bearer network I and carrier network III fails, and the link between the master clock source and carrier network II fails is: time system 2 → bearer network 1 → bearer network 2 and time system 3. The bearer network equipment transmits the clock signal to all the 5G base stations connected to it, realizing the clock synchronization between base stations in the 5G system. Figure 7 As shown in the figure, the clock tracking relationship under the link failure between bearer network II and carrier network III, and the link failure between the main clock source and carrier network II is: time system 2 → bearer network 1 → bearer network 2 and bearer network 3. The bearer network equipment transmits the clock signal to all the 5G base station equipment connected to it, realizing the clock synchronization between base stations in the 5G system.

[0052] In this way, if any node device (clock source or bearer network) or any link between two nodes of the shipborne 5G clock synchronization system fails, the clock tracking and switching can be automatically completed to ensure normal clock synchronization of the shipborne 5G system and high anti-destruction performance.

[0053] As an improvement, when the clock link and / or the main clock source between the bearer network II and the main clock source fails, the node device first keeps the internal oscillator of its own device in free oscillation, and starts the timer at the same time. If the clock link and / or the main clock source between the bearer network II and the main clock source recover after the timer reaches the set duration, the clock tracking relationship under normal circumstances will continue to be executed, otherwise, the clock tracking relationship under the clock link protection situation will be executed. In this way, because the shipboard power supply is unstable in the shipborne environment, the main clock source will have a momentary power failure and restart, so the switching mechanism of the main clock source and the backup clock source avoids the immediate switching of the main clock source to the backup clock source in this case, reducing the waste of resources caused by the frequent switching between the main clock source and the backup clock source.

[0054] As a further improvement, when the shipborne 5G clock synchronization system is executing the clock tracking relationship under the clock link protection condition, if the clock link and / or the main clock source fault between the bearer network II and the main clock source is restored and the node device can detect the clock message of the main clock source, the timer is started at the same time. If the node device can still detect the clock message of the main clock source after the timer reaches the set duration, the clock tracking relationship under normal conditions is executed, otherwise the clock tracking relationship under the clock link protection condition is still maintained. In this way, under normal circumstances, the main clock source is prioritized to provide clock synchronization services for the entire shipborne 5G system, and it is not immediately switched to the main clock source after the clock link and / or the main clock source fault between the bearer network II and the main clock source is restored, which avoids frequent restarts of the main clock source and frequent switching of the main clock source and the backup clock source, thereby facilitating the maintenance of the entire shipborne 5G system and reducing the waste of resources caused by frequent switching between the main clock source and the backup clock source.

[0055] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A shipborne 5G clock synchronization system, characterized in that: At least including the main clock source, backup clock source, bearer network I, bearer network II, bearer network III, 5G base station, and 5G core network; The master clock source and the backup clock source are used to provide clock messages to the bearer network composed of the bearer network I, the bearer network II and the bearer network III, and the priority of the master clock source is higher than that of the backup clock source; The bearer network I, the bearer network II and the bearer network III are all connected to the 5G core network and the 5G base station signal; The main clock source, the backup clock source and the 5G base station are common clock nodes; The bearer network I, the bearer network I and the bearer network III are boundary clock nodes; The main clock source and the backup clock source are both 1588V2 clocks.

2. A shipborne 5G clock synchronization system according to claim 1, characterized in that: The main clock source and the backup clock source are deployed in cabins of different partitions on the ship.

3. A shipborne 5G clock synchronization method, characterized in that: A shipborne 5G clock synchronization system based on claim 1 or 2, and: The clock tracking relationship performed under normal circumstances is: the bearer network II tracks the main clock source, the bearer network III tracks the bearer network II, and the bearer network I tracks the bearer network III; When any node device or the link between any two nodes of the shipborne 5G clock synchronization system fails, the clock tracking relationship under the clock link protection condition is executed: the bearer network II tracks the main clock source, the bearer network III and the bearer network I respectively, and in the clock link, the priority of the clock link between the bearer network II and the main clock source is priority one, the priority of the clock link between the bearer network II and the bearer network III is priority two, and the priority of the clock link between the bearer network II and the bearer network I is priority three; the bearer network III tracks the bearer network II and the bearer network I respectively, and in the clock link, the priority of the clock link between the bearer network III and the bearer network II is priority one, and the priority of the clock link between the bearer network III and the bearer network I is priority two; the bearer network I tracks the bearer network III and the backup clock source respectively, and in the clock link, the priority of the clock link between the bearer network I and the bearer network III is priority one, and the priority of the clock link between the bearer network I and the backup clock source is priority two.

4. A shipborne 5G clock synchronization method according to claim 3, characterized in that: When the clock link and / or the main clock source between the bearer network II and the main clock source fails, the node device first keeps the internal oscillator of its own device in free oscillation and starts the timer at the same time. After the timer reaches the set duration, if the clock link and / or the main clock source between the bearer network II and the main clock source fails, the clock tracking relationship under normal circumstances continues to be executed; otherwise, the clock tracking relationship under clock link protection is executed.

5. A shipborne 5G clock synchronization method according to claim 3 or 4, characterized in that: When the shipborne 5G clock synchronization system is executing the clock tracking relationship under the clock link protection condition: If the clock link between the bearer network II and the main clock source and / or the main clock source failure is restored and the node device can detect the clock message of the main clock source, the timer is started at the same time. After the timer reaches the set duration, if the node device can still detect the clock message of the main clock source, the clock tracking relationship under normal circumstances is executed.

6. A shipborne 5G clock synchronization method according to claim 5, characterized in that: If the node device fails to detect the clock message of the clock source after the timer reaches the set time, the clock tracking relationship under the clock link protection condition is still maintained.

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