Method, device, equipment and system for providing clock reference source for base station

Abstract

The invention discloses a method, a device, equipment and a system for providing a clock reference source for a base station. The method comprises the following steps: respectively introducing a main clock source and a standby clock source at different nodes of the OTN; transmitting the main clock source and the standby clock source to a third node of the network through a main line and a standby line which are mutually independent in the network, so that the third node receives four paths of clock signals; at the third node, selecting the clock signal to generate a first bearer network clock and a second bearer network clock; respectively outputting the first bearer network clock and the second bearer network clock to a first bearer network and a second bearer network, and establishing a clock cross-linking mechanism between the first bearer network and the second bearer network; and providing clock tracking for base stations under the first bearer network and the second bearer network based on the first bearer network clock, the second bearer network clock or a clock signal obtained through a clock cross-linking mechanism. According to the invention, an efficient and reliable clock reference source can be provided for the base station.

Description

Technical Field

[0001] This invention relates to the field of network communication technology, and in particular to a method, apparatus, device and system for providing a clock reference source for a base station. Background Technology

[0002] With the commercial deployment of 5G and future mobile communication networks, the requirements for clock synchronization accuracy are becoming increasingly stringent. In order to support key applications such as precise uplink and downlink switching of TDD (Time Division Duplex) systems, collaborative transmission of CoMP (Cooperative Multipoint) technology, and high-precision positioning, base stations must have high-precision time synchronization capabilities to ensure normal transmission and reception of wireless signals and interference control.

[0003] In this context, base stations typically obtain a high-precision clock reference source from the core network via the bearer network. Among these, network time synchronization technology based on the IEEE 1588v2 (PTP) protocol has become the mainstream solution due to its ability to accurately transmit time and phase information. These synchronization signals are generated by the high-precision clock source of the core node and are transmitted transparently through high-capacity, low-latency transmission networks such as OTN (Optical Transport Network) before finally reaching the base station access side.

[0004] However, existing technologies suffer from fundamental deficiencies in the reliability design of the clock reference source for base stations, making it difficult to meet the stringent high availability requirements of 5G networks. This manifests in two main ways:

[0005] First, the clock transmission path carries the risk of a "single point of failure." Most solutions employ a single-path transmission method, transmitting the primary clock source cascaded down the path. This architecture is highly dependent on the stability of a single physical link. If this link experiences a sudden event such as fiber optic cable interruption, equipment malfunction, or board failure, the clock signal may be lost, leading to large-scale synchronization failures at base stations and severely impacting service continuity and overall network stability.

[0006] Secondly, the system lacks a comprehensive, multi-layered redundancy protection mechanism. Even when some solutions incorporate redundancy, they are mostly limited to end-to-end path switching, failing to establish deep protection measures that penetrate the entire transmission network. This design is particularly vulnerable to multiple or complex faults in complex network environments, significantly limiting the system's disaster recovery capabilities and the overall availability of the network. Summary of the Invention

[0007] The technical problem to be solved by this invention is to address the aforementioned shortcomings of the prior art by proposing a method, apparatus, device, and system for providing a clock reference source for base stations. This method constructs a highly reliable clock reference source supply system, thereby significantly improving the synchronization stability and disaster recovery capability of the entire mobile communication system.

[0008] In a first aspect, the present invention provides a method for providing a clock reference source for a base station, the method comprising the following steps:

[0009] A primary clock source is introduced at the first node of the OTN network, and a backup clock source is introduced at the second node of the OTN network;

[0010] The primary and backup clock sources are transmitted to the third node of the OTN network through the independent primary and backup lines, so that the third node can receive four clock signals.

[0011] The four clock signals include a first master clock signal transmitted through the master line, a first backup clock signal transmitted through the master line, a second master clock signal transmitted through the backup line, and a second backup clock signal transmitted through the backup line.

[0012] At the third node, the first master clock signal and the first backup clock signal are selected to generate the first bearer network clock; at the same time, the second master clock signal and the second backup clock signal are selected to generate the second bearer network clock.

[0013] Among them, the first master clock signal has a higher priority than the first backup clock signal, and the second master clock signal has a higher priority than the second backup clock signal.

[0014] The clocks of the first and second bearer networks are output to the first and second bearer networks respectively, and a clock crossover mechanism is established between the first and second bearer networks.

[0015] Specifically, when the first bearer network loses its received clock signal, it obtains the clock signal from the second bearer network through a clock crossover mechanism; when the second bearer network loses its received clock signal, it obtains the clock signal from the first bearer network through a clock crossover mechanism.

[0016] Based on the clock signals obtained from the first bearer network clock, the second bearer network clock, or through a clock crossover mechanism, clock tracking is provided for the base stations connected to the first and second bearer networks, so as to provide a clock reference source for the base stations.

[0017] Furthermore, both the primary clock source and the backup clock source use 1588V2 clock messages.

[0018] Furthermore, the first node and the second node are located at different local stations.

[0019] Furthermore, the OTN network has a ring network structure.

[0020] Furthermore, the protection mechanisms for the primary and backup lines are Optical Multiplex Section Protection (OMSP) or Optical Line Protection (OLP).

[0021] Furthermore, the first bearer network clock and the second bearer network clock are output by completely independent clock boards on the third node, and are transmitted using different physical optical fibers.

[0022] Furthermore, an anti-trace mechanism is set up between the downstream base stations of the first and second bearer networks.

[0023] In a second aspect, the present invention provides an apparatus for providing a clock reference source for a base station, the apparatus comprising:

[0024] The clock source introduction unit is used to introduce a primary clock source at the first node of the OTN network and to introduce a backup clock source at the second node of the OTN network.

[0025] The clock pass-through unit, connected to the clock source input unit, is used to pass through the primary and backup clock sources to the third node of the OTN network through the independent primary and backup lines in the OTN network, so that the third node can receive four clock signals.

[0026] The four clock signals include a first master clock signal transmitted through the master line, a first backup clock signal transmitted through the master line, a second master clock signal transmitted through the backup line, and a second backup clock signal transmitted through the backup line.

[0027] The group selection unit, connected to the clock pass-through unit, is used at the third node to select the first master clock signal and the first backup clock signal to generate the first bearer network clock; at the same time, it selects the second master clock signal and the second backup clock signal to generate the second bearer network clock.

[0028] Among them, the first master clock signal has a higher priority than the first backup clock signal, and the second master clock signal has a higher priority than the second backup clock signal.

[0029] The processing unit, connected to the group selection unit, is used to output the first bearer network clock and the second bearer network clock to the first bearer network and the second bearer network respectively, and to establish a clock crossover mechanism between the first bearer network and the second bearer network.

[0030] Specifically, when the first bearer network loses its received clock signal, it obtains the clock signal from the second bearer network through a clock crossover mechanism; when the second bearer network loses its received clock signal, it obtains the clock signal from the first bearer network through a clock crossover mechanism.

[0031] A clock tracking providing unit, connected to the processing unit, is used to provide clock tracking for base stations connected to the first and second bearer networks based on the clock signals obtained from the first bearer network clock, the second bearer network clock, or through a clock crossover mechanism, so as to provide a clock reference source for the base stations.

[0032] Thirdly, the present invention provides an electronic device including a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor performs the method for providing a clock reference source for a base station according to the first aspect.

[0033] Fourthly, the present invention provides a system for providing a clock reference source for a base station, the system being used to implement the method for providing a clock reference source for a base station as described in the first aspect, the system comprising:

[0034] The primary clock source module and the backup clock source module are respectively located at different access points of the optical transport network;

[0035] The optical transport network module is equipped with path protection function, which is used to transparently transmit multiple clock signals to network nodes;

[0036] A clock processing unit, located at the network node, is used to group and select multiple clock signals and generate at least two output clock signals.

[0037] At least two bearer network modules are used to receive the output clock signal and provide a clock reference for the base station;

[0038] A cross-connection protection link is connected between different bearer network modules to provide a backup clock path through the normally functioning bearer network module when the clock input of any of the bearer network modules fails, thereby ensuring the continuity and reliability of the clock reference.

[0039] This invention constructs a highly reliable clock reference source supply system by deeply integrating dual-path redundancy, multi-level optimization, and bearer network mutual backup technologies in the OTN network, thereby significantly improving the synchronization stability and disaster recovery capability of the entire mobile communication system. The specific beneficial effects are as follows:

[0040] (1) Enhance the reliability and redundancy of clock transmission.

[0041] This invention achieves dual-channel, dual-route redundant transmission at the physical layer by introducing a primary clock source at the first node and a backup clock source at the second node in the OTN network, and by using independent primary and backup lines for signal pass-through. This design effectively avoids the risk of single-point failure and greatly improves the reliability of clock signal transmission paths.

[0042] (2) To achieve fine-grained optimization control of multiple clock signals.

[0043] This invention receives four clock signals from two independent paths at the third node and generates a first bearer network clock and a second bearer network clock based on a preset priority strategy. This mechanism not only has path redundancy capability but also achieves intelligent optimization at the clock source level, ensuring that the system always outputs the optimal available clock signal.

[0044] (3) Construct a horizontal interconnection and mutual backup mechanism between bearer networks to improve the system's disaster recovery capability.

[0045] This invention establishes a clock crossover mechanism between the first and second bearer networks, enabling either bearer network to automatically switch to the other bearer network to obtain a backup clock source when either loses its own clock input. This design achieves cross-network layer mutual backup, significantly enhancing the system's continuous service capability and overall resilience.

[0046] (4) Supports seamless switching between multiple scenarios to ensure high system availability.

[0047] This invention can flexibly cope with various fault scenarios such as master clock source failure, transmission line interruption, and bearer network out of sync. Through built-in optimization logic and cross-connection switching mechanism, it ensures that a stable clock reference is continuously provided to the base station, effectively guaranteeing uninterrupted service.

[0048] (5) It is compatible with the existing network architecture, making it easy to deploy and upgrade.

[0049] This invention is built on a standard OTN network, eliminating the need to build a new dedicated synchronization network. It can fully utilize existing network transmission resources to achieve high-precision clock distribution, making it suitable for high-requirement synchronization scenarios such as large-scale deployment of 5G base stations and industry private networks. It has good engineering applicability and scalability.

[0050] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0051] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. The above and other features and advantages will become more apparent to those skilled in the art from the detailed description of exemplary embodiments with reference to the accompanying drawings, in which:

[0052] Figure 1 This is a schematic diagram of a method for providing a clock reference source for a base station according to an embodiment of the present invention;

[0053] Figure 2 This is a clock tracking diagram illustrating the provision of a clock reference source for a base station, provided as an embodiment of the present invention.

[0054] Figure 3 A schematic diagram of an apparatus for providing a clock reference source for a base station, provided in an embodiment of the present invention;

[0055] Figure 4 This is a block diagram of an electronic device provided in an embodiment of the present invention.

[0056] Reference numerals: 10, clock source introduction unit; 20, clock pass-through unit; 30, group selection unit; 40, processing unit; 50, clock tracking provision unit; 100, processor; 200, memory. Detailed Implementation

[0057] It is understood that the specific embodiments and accompanying drawings described herein are merely for explaining the invention and are not intended to limit the invention.

[0058] It is understood that, without conflict, the various embodiments and features in the embodiments of the present invention can be combined with each other.

[0059] It is understood that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, while the parts unrelated to the present invention are not shown in the drawings.

[0060] It is understood that each unit or module involved in the embodiments of the present invention may correspond to only one entity structure, or may be composed of multiple entity structures, or multiple units or modules may be integrated into one entity structure.

[0061] It is understood that, without conflict, the functions and steps marked in the flowcharts and block diagrams of this invention may occur in a different order than that marked in the accompanying drawings.

[0062] It is understood that the flowcharts and block diagrams of this invention illustrate the possible architecture, functions, and operations of systems, apparatuses, devices, and methods according to various embodiments of this invention. Each block in the flowchart or block diagram may represent a unit, module, program segment, or code, containing executable instructions for implementing the specified function. Furthermore, each block or combination of blocks in the block diagram and flowchart can be implemented using a hardware-based system to achieve the specified function, or using a combination of hardware and computer instructions.

[0063] It is understood that the units and modules involved in the embodiments of the present invention can be implemented by software or by hardware. For example, the units and modules can be located in a processor.

[0064] In modern communication networks, the requirements for clock synchronization in various mobile communication systems (such as 2G / 3G / 4G / 5G) are constantly increasing, especially in terms of high-precision time synchronization, where reliance on satellite navigation systems such as GPS has become the mainstream solution. However, GPS timing modules are widely used in early devices and their proportion is extremely low, leading to serious security and stability risks when the system encounters GPS signal interference, failure, or interference. For example, GPS signals may be subject to human interference, signal interruption, or blockage. Once such an event occurs, it may trigger large-scale network synchronization failures, affecting the continuity of communication services.

[0065] To ensure the security and stability of communication networks, the gradual introduction of terrestrial clock reference sources has become an inevitable trend. Currently, network synchronization is achieved by transmitting clock signals according to the IEEE 1588v2 (PTP) protocol using hybrid networking technologies such as OTN, IPRAN, and PTN. Due to insufficient support for the 1588v2 protocol in early OTN equipment or boards, solutions have emerged that add independent clock boards and software modules to the optical transmission network to build a separate clock network. However, these solutions have certain limitations in practical applications, such as complex management, poor equipment compatibility, and the unresolved issue of ensuring stable clock signal transmission when link failures occur (such as fiber optic cable breaks, single node or board failures).

[0066] In view of this, the present invention aims to provide a method, apparatus, and system for providing a highly reliable, continuous, and stable 1588v2 clock reference source for communication base stations. This solution leverages the multi-routing advantages of OTN networks (such as OMSP or OLP multi-routing technologies) to ensure a stable 1588v2 clock signal for base stations even in the event of sudden events such as line interruptions, board failures, or node failures, thereby enhancing the network's disaster recovery capabilities and synchronization stability. Through a rationally designed hardware structure and management mechanism, multi-route parallel transmission, automatic switching, and fault recovery are achieved, thereby improving the overall network synchronization security and providing strong technical support for high-precision and secure mobile communication networks.

[0067] Example 1:

[0068] This embodiment provides a method for providing a clock reference source for a base station. The method provided in this embodiment is applicable to various communication base stations when facing interference, failure or restriction of satellite navigation signals, ensuring the continuous, stable and high-precision synchronization of the network clock. It is particularly suitable for multi-route transmission scenarios in complex network environments, time guarantee of critical infrastructure, and response to sudden failures and interference events, ensuring the security and reliability of the communication network.

[0069] like Figure 1As shown, the method for providing a clock reference source for a base station provided in this embodiment specifically includes the following steps S1 to S5.

[0070] Step S1: Introduce a primary clock source at the first node of the OTN network and a backup clock source at the second node of the OTN network.

[0071] In one specific implementation, the first node and the second node are located at different local stations.

[0072] In the clock transmission architecture of this embodiment, two independent high-precision time synchronization sources are first deployed in the OTN (Optical Transport Network) network as the primary and backup clock sources, respectively, to achieve redundancy protection at the clock input level. Specifically, the primary clock source is connected to the first node in the OTN network. This node is typically located in a core or aggregation station with good clock acquisition conditions, such as being equipped with a high-stability atomic clock or a high-precision PTP (Grandmaster Clock) locked via satellite common-view technology, used to generate and inject a precise time signal that conforms to the 1588v2 protocol requirements. Simultaneously, the backup clock source is connected to the second node in the OTN network. This node is located in a different physical station than the first node and has an independent optical cable route and power supply system, ensuring that the two are isolated from each other in terms of spatial location, infrastructure, and fault domain. This cross-station deployment method effectively avoids the risk of simultaneous failure of the primary and backup clocks due to common-cause failures such as power outages, fires, human error, or local natural disasters at a single station. The backup clock source also possesses high-precision timekeeping capabilities, synchronizing with the primary clock source under normal operating conditions. When the primary clock source or its transmission path malfunctions, the system can quickly switch to the backup clock source injected by the second node to continue providing service, thus ensuring the continuity and reliability of the time base for the entire OTN network and downstream base stations. By deploying primary and backup clock sources at two geographically separated stations, not only is the disaster recovery capability of the clock input improved, but the foundation is also laid for subsequent implementation of end-to-end clock path redundancy using OTN layer OMSP or OLP protection mechanisms.

[0073] In this embodiment, both the primary and backup clock sources use 1588v2 clock messages. Specifically, the primary and backup clock sources both conform to the IEEE 1588v2 (Precision Time Protocol, PTP) standard. The primary clock source is generated by the PTP master clock (GrandmasterClock) deployed on the first node. This master clock is synchronized using a high-precision time reference (such as satellite common-view or atomic clocks), encapsulating a 1588v2 synchronization message with a precise timestamp, and injecting it into the OTN network. Similarly, the backup clock source is generated by the PTP master clock on the second node, also outputting standard 1588v2 clock messages as a substitute time reference when the primary path fails. In this embodiment, the "clock source" does not refer to the physical device itself, but rather to the time signal carrier it provides, namely the 1588v2 protocol frame, including message types such as Sync, Follow_Up, Delay_Req, and Delay_Resp, used to transmit UTC time information and achieve end-to-end time synchronization in the network. The two clock sources are located on OTN nodes at different stations, logically forming a dual-homed redundancy structure. Under normal circumstances, the network uses 1588v2 messages injected by the primary node as the network-wide time reference. When the primary clock source is lost, a message is abnormal, or the transmission path is interrupted, the system automatically switches to 1588v2 messages injected by the backup node to continue distributing clock signals to lower-level networks and base stations. By unifying the primary and backup clock sources into the 1588v2 message format, the OTN network's capacity to carry packet clock signals can be fully utilized, and it can work in conjunction with subsequent OMSP / OLP protection mechanisms to achieve a highly reliable terrestrial clock distribution system based on standard protocols, interoperability, and easy expansion.

[0074] As a specific implementation method, the OTN network adopts a ring network structure. When the OTN network adopts a ring network structure, it possesses significant advantages in topological redundancy and high reliability. In the ring network architecture, multiple OTN nodes are connected end-to-end via fiber optic links, forming a closed transmission loop that supports bidirectional or multi-path data transmission. When a segment of optical cable in the network is interrupted, a single board fails, or a node fails, the ring network can switch service traffic to the reverse or other available paths within milliseconds through preset protection mechanisms (such as OMSP optical multiplex section protection or ring network automatic protection switching protocol), achieving rapid self-healing and ensuring service continuity. This structure is particularly suitable for stable clock signal transmission because 1588v2 messages are sensitive to packet loss, jitter, and path asymmetry. The ring network not only provides physical-level dual-route redundancy but can also combine clock path optimization algorithms to ensure the latency consistency of the primary and backup paths, reducing synchronization errors. In addition, the ring network structure facilitates network expansion and hierarchical deployment, supports step-by-step clock distribution from the core to the aggregation and then to the access layer, and is conducive to building a unified, controllable, and disaster-tolerant end-to-end ground clock synchronization system. It is especially suitable for providing a highly available 1588v2 clock reference source for multi-generation base stations (2G / 3G / 4G / 5G).

[0075] As a specific implementation method, the protection mechanisms for the primary and backup lines are Optical Multiplex Section Protection (OMSP) or Optical Line Protection (OLP). Employing OMSP or OLP mechanisms for both primary and backup lines offers significant advantages such as high reliability, rapid switching, and transparency to upper-layer services. OMSP implements dual-route redundancy at the optical multiplex section level. By monitoring the optical power or bit error rate of the primary optical channel in real time, it can automatically switch to the backup optical path within 50ms when an optical cable interruption, laser failure, or severe signal degradation is detected, ensuring continuous transmission of 1588v2 clock messages carried by the OTN layer and preventing clock interruptions due to single-point failures. OLP, on the other hand, operates at a lower-level optical physical line, directly providing dual-path backup for the fiber optic link. It is suitable for long-distance transmission scenarios across different offices and has stronger environmental adaptability and fault response capabilities. Both protection mechanisms are implemented at the hardware level, independent of upper-layer protocol processing. They offer advantages such as independence from service type and no need for PTP protocol involvement, effectively addressing common issues like fiber optic cable breakage, connector aging, and board failures, ensuring stable transmission of clock signals in complex network environments. Especially when introduced into ring or chain-type networks, OMSP / OLP can collaborate with the 1588v2 protocol to form a dual "physical layer + protocol layer" protection, significantly improving the robustness and availability of the ground clock distribution system and meeting the stringent requirements of communication base stations for high-precision, high-reliability time synchronization.

[0076] Step S2: Through the independent primary and backup lines in the OTN network, the primary clock source and backup clock source are transmitted to the third node of the OTN network so that the third node receives four clock signals; the four clock signals include the first primary clock signal transmitted by the primary line, the first backup clock signal transmitted by the primary line, the second primary clock signal transmitted by the backup line, and the second backup clock signal transmitted by the backup line.

[0077] Step S3: At the third node, the first master clock signal and the first backup clock signal are optimized to generate the first bearer network clock; at the same time, the second master clock signal and the second backup clock signal are optimized to generate the second bearer network clock; the first master clock signal has a higher priority than the first backup clock signal, and the second master clock signal has a higher priority than the second backup clock signal.

[0078] Step S4: Output the clock signals of the first bearer network and the second bearer network to the first bearer network and the second bearer network respectively, and establish a clock crossover mechanism between the first bearer network and the second bearer network; when the first bearer network loses its received clock signal, it obtains the clock signal from the second bearer network through the clock crossover mechanism; when the second bearer network loses its received clock signal, it obtains the clock signal from the first bearer network through the clock crossover mechanism.

[0079] This embodiment employs a dual physical isolation principle of hardware and link to construct a highly reliable clock synchronization channel. Specifically, the first and second bearer network clocks are output by completely independent clock boards located at the third node and transmitted through different physical optical fibers, ensuring complete isolation between them. On the third node of the OTN network, dedicated, independent clock boards are configured for the output of the first and second bearer network clocks. This means that each clock signal has its own dedicated physical processing unit, fundamentally avoiding the risk of total clock interruption due to board failure or maintenance. Furthermore, after being output from the node, these two clock signals are transmitted through different physical optical fibers, ensuring that the clock link and service link are physically completely separated. This design ensures that clock signal transmission is unaffected by service traffic fluctuations, service link interruptions, or equipment port failures, forming a clean, stable, and protected "dedicated clock network," thereby providing a highly available clock reference source for the bearer network and its connected base stations.

[0080] As a specific implementation method, the clock cross-connection mechanism follows a primary / backup priority principle when acquiring clock signals. That is, the first primary clock signal has a higher priority than the first backup clock signal, and the second primary clock signal has a higher priority than the second backup clock signal. This mechanism achieves determinism and stability in clock source selection through a clear priority order, effectively avoiding problems such as multi-source contention, clock oscillation, or switching chaos. During normal network operation, the system strictly locks the high-priority primary clock signal as the synchronization reference, ensuring unified clock traceability across the entire network and reducing phase jitter and time deviation caused by frequent switching. When the primary clock signal is lost, degraded, or exceeds a threshold, the system automatically and seamlessly switches to the backup signal of the corresponding channel, ensuring clock continuity. This hierarchical priority management strategy not only improves the reliability of the clock selection logic but also supports flexible operation and maintenance control. For example, planned switching or network reconstruction can be achieved through manual priority settings. Combined with physical protection mechanisms (such as OMSP / OLP) in OTN networks, the primary / backup priority principle further enhances the disaster recovery capability of end-to-end clock transmission, ensuring that high-precision time synchronization can still be maintained quickly and orderly under complex fault scenarios, meeting the stringent requirements of 2G / 3G / 4G and 5G base stations for clock stability and predictability.

[0081] Step S5: Based on the clock signal obtained from the first bearer network clock, the second bearer network clock, or through the clock crossover mechanism, provide clock tracking for the base stations connected to the first bearer network and the second bearer network, so as to provide a clock reference source for the base stations.

[0082] As a specific implementation method, an anti-mutual-tracking mechanism is set up between the base stations connected to the first and second bearer networks. This mechanism, through logical isolation or protocol control, prevents base stations under different bearer networks from tracking each other and forming clock loops due to clock path coupling. Its core advantage lies in avoiding the synchronization failure risk caused by "clock mutual tracking"—that is, when two clock domains that should operate independently, base station A uses B as its clock source, and B, in turn, tracks A, causing false synchronization or oscillation, ultimately leading to instability of the entire network's time base. By deploying anti-mutual-tracking mechanisms, such as unique master control determination based on the BMC (BestMaster Clock) algorithm, port role locking, clock path identification (such as UTC domain labels, network layer identifiers), or topology awareness functions, it can be ensured that each base station can only synchronize with the upstream designated primary and backup clock sources, and will not track downstream nodes in reverse across the network, thereby maintaining a clear clock distribution hierarchy. This mechanism is particularly important in OTN dual-homing, ring network redundancy, or cross-connection protection scenarios. It not only improves the accuracy and security of the 1588v2 protocol source selection in multi-path environments, but also enhances the robustness and maintainability of the entire ground clock synchronization network, ensuring that high-precision time signals are stably, unidirectionally, and reliably transmitted to all base station nodes in complex network configurations.

[0083] The following specific case illustrates this embodiment. This case fully leverages the multi-routing advantages of OTN networks' OMSP or OLP, deploying multiple clock routes at the OTN layer and employing a selective reception mode at the landing site. This greatly ensures the stability of the terrestrial 1588V2 clock, clearly demonstrating the feasibility of long-distance transmission of the 1588V2 clock, allowing for confident deployment and reducing investment in miniaturized, recessed clock sources. The specific process is as follows:

[0084] like Figure 2 As shown, this embodiment provides a method for a base station to provide a 1588v2 clock reference source, which includes at least a master clock source, a backup clock source, an OTN network, a bearer network E1, a bearer network E2, a bearer network, and a base station; wherein the OTN board supports the 1588v2 clock, and the OTN network has OMSP or OLP protection.

[0085] Under normal circumstances, the clock tracking relationship between base station 1 and base station 2 is as follows: After OTN A node introduces the primary clock sources T1 and T2, it transmits the T1 clock to the primary line in the OTN B direction and the T2 clock to the backup line in the OTN B direction through service configuration. The T1 and T2 clock signals have the same priority and are both primary clock source signals. After OTN D node introduces the backup clock sources T3 and T4, it transmits the T3 clock to the primary line in the OTN C direction and the T4 clock to the backup line in the OTN C direction through service configuration. The T3 and T4 clock signals have the same priority and are both backup clock source signals. OTN B and OTNC nodes not only receive signals, but the OTNB also transmits the T1 and T2 clocks from the OTN A direction to the OTN C direction through the primary and backup lines respectively. The OTNC transmits the T3 and T4 clocks from the OTN D direction to the OTN B direction through the primary and backup lines respectively. For OTN C, four clocks are received: T1 clock from the primary line in the OTN B direction, T2 clock from the backup line in the OTN B direction, T3 clock from the primary line in the OTN D direction, and T4 clock from the backup line in the OTN D direction. At the OTN C node, through data configuration, clocks T1 and T3, and clocks T2 and T4 are divided into two groups and selected for reception according to clock priority. Since T1 > T3 and T2 > T4, clock T5 of bearer network E1 is the T1 clock, and clock T6 of bearer network E2 is the T2 clock. Further, according to the bearer network clock tracking strategy, bearer F tracks bearer A clock—T1, and bearer G tracks bearer E2 clock—T2. Base station 1 tracks bearer F clock—T1 (the primary clock source), and base station 2 tracks bearer G clock—T2 (the primary clock source).

[0086] When any node device or link between any two nodes fails in the OTN B direction, the clock tracking relationship between base station 1 and base station 2 is as follows: If clock T1 is lost, the bearer E1 selects to receive clock T3 and provides it to base station 1 as a backup clock source, while the clock source tracked by base station 2 remains unchanged; if clock T2 is lost, the bearer E2 selects to receive clock T4 and provides it to base station 2 as a backup clock source, while the clock source tracked by base station 1 remains unchanged; if both clocks T1 and T2 are lost, the bearer E1 selects to receive clock T3 and provides it to base station 1 as a backup clock source, and the bearer E2 selects to receive clock T4 and provides it to base station 2 as a backup clock source.

[0087] When any node device or link between any two nodes fails in the OTN D direction, the clock tracking relationship between base station 1 and base station 2 is as follows: if clock T3 is lost, the clock source tracked by base station 1 and base station 2 remains unchanged; if clock T4 is lost, the clock source tracked by base station 1 and base station 2 remains unchanged; if both clocks T3 and T4 are lost, the clock source tracked by base station 1 and base station 2 remains unchanged.

[0088] When a node device or link failure occurs in the OTN B and OTND directions respectively (the four lines of OTN C cannot be interrupted simultaneously, or node device disconnection failures cannot occur simultaneously on both sides, i.e., the OTN C node cannot be unavailable), the clock tracking relationship between base station 1 and base station 2 is as follows: If clocks T1 and T3 are lost, then bearer E2 still tracks clock T2 unchanged. Both clock sources for bearer E1 clock T5 are lost, and it obtains clock T6 from the crosslink of bearer E1 to bearer E2. That is, base station 1 tracks clock T2—the primary clock source, while base station 2's clock remains unchanged. If clocks T1, T2, and T3 are lost, then bearer E2's clock T6 can only receive clock T4. Base station 2 tracks clock T4 (the backup clock source). Both clock sources for bearer E1 clock T5 are lost, and it obtains clock T6 from the crosslink of bearer E1 to bearer E2. The crosslink of base station 2 obtains clock T6, meaning base station 1 also tracks clock T4 – a backup clock source. If clocks T1, T2, and T4 are lost, then clock T5 carrying E1 can only receive clock T3, and base station 1 tracks clock T3. Since both clock sources for clock T6 carrying E2 are lost, it obtains clock T5 from the crosslink between E1 and E2, meaning base station 2 also tracks clock T3 – a backup clock source. If clocks T1, T3, and T4 are lost, then clock T6 carrying E2 selects clock T2, meaning base station 2's clock remains unchanged – clock T2. Since both clock sources for clock T5 carrying E1 are lost... If the clocks T1, T2, and T4 are lost, the clock T5 for E1 will be the T1 clock, meaning the base station 1 clock will remain unchanged – the T1 clock. If both clock sources for E2's clock T6 are lost, it will be the T5 clock for E1, meaning the base station 1 clock will remain unchanged – the T1 clock. If both clock sources for E2's clock T6 are lost, it will be the T5 clock for E1, meaning the base station 2 clock will also be the T1 clock – the main clock source. If the T1 and T4 clocks are lost, the clock T5 for E1 will track the T3 clock, meaning the base station 1 will track the T3 clock – the backup clock source. The clock T6 of E2 tracks the clock T2, meaning the clock tracked by base station 2 remains unchanged. If clocks T2 and T3 are lost, then the clock T5 carrying E1 tracks the clock T1, meaning the clock tracked by base station 1 remains unchanged. The clock T6 carrying E2 tracks the clock T4, meaning base station 2 tracks the clock T4 – the backup clock source. If clocks T2 and T4 are lost, then the clock T5 carrying E1 tracks the clock T1, meaning the clock tracked by base station 1 remains unchanged. Both clock sources of the clock T6 carrying E2 are lost, and the clock T5 is tracked from the cross link carrying E1 to carrying E2, meaning the clock of base station 2 is also the clock T1 – the master clock source.

[0089] Thus, this embodiment ensures that the base station can receive a stable 1588V2 ground clock even when the OTN experiences a single fault or multiple faults. As the equipment or line faults are gradually restored, and the clock links T1, T2, T3, and T4 are gradually restored, the OTNC node, bearer E1, and bearer E2 devices will perform clock tracking relationships according to the clock source transmission situation under the different circumstances described above, until the system returns to normal.

[0090] This embodiment provides a highly reliable, multi-layered redundant base station clock reference source supply method. By introducing primary and backup 1588v2 clock sources into different stations within the OTN network, and utilizing the OTN ring network structure and OMSP / OLP physical layer protection mechanisms, stable transmission of clock signals under multi-route conditions is achieved. At the third node, four clock signals from dual paths are selected based on priority to generate first and second bearer network clocks. A clock cross-connection mechanism ensures mutual backup between the two bearer networks. Even if a link or device failure in either direction leads to clock loss, a usable clock source can still be obtained through the cross-connection path, ensuring downstream base stations continuously receive high-precision synchronization signals. Simultaneously, an anti-tracking mechanism prevents cross-domain synchronization loops, ensuring a clear, unidirectional, and controllable clock topology. This solution fully leverages the self-healing capability and dual-homing architecture of the OTN network, maintaining clock continuity in single-point or multi-point failure scenarios. It significantly improves the stability and security of terrestrial 1588v2 clock distribution, effectively supporting the high-availability time synchronization requirements of 2G / 3G / 4G / 5G multi-generation base stations, and possesses good deployability and resilience.

[0091] Example 2:

[0092] like Figure 3 As shown, this embodiment provides an apparatus for providing a clock reference source for a base station, the apparatus comprising:

[0093] The clock source introduction unit 10 is used to introduce a primary clock source at the first node of the OTN network and to introduce a backup clock source at the second node of the OTN network.

[0094] The clock pass-through unit 20 is connected to the clock source introduction unit 10 and is used to pass through the main clock source and the backup clock source to the third node of the OTN network through the independent main line and backup line in the OTN network, so that the third node can receive four clock signals.

[0095] The four clock signals include a first master clock signal transmitted through the master line, a first backup clock signal transmitted through the master line, a second master clock signal transmitted through the backup line, and a second backup clock signal transmitted through the backup line.

[0096] The group selection unit 30 is connected to the clock transmission unit 20 and is used at the third node to select the first master clock signal and the first backup clock signal to generate the first bearer network clock; at the same time, it selects the second master clock signal and the second backup clock signal to generate the second bearer network clock.

[0097] Among them, the first master clock signal has a higher priority than the first backup clock signal, and the second master clock signal has a higher priority than the second backup clock signal.

[0098] The processing unit 40 is connected to the group selection unit 30 and is used to output the first bearer network clock and the second bearer network clock to the first bearer network and the second bearer network respectively, and to establish a clock crossover mechanism between the first bearer network and the second bearer network.

[0099] Specifically, when the first bearer network loses its received clock signal, it obtains the clock signal from the second bearer network through a clock crossover mechanism; when the second bearer network loses its received clock signal, it obtains the clock signal from the first bearer network through a clock crossover mechanism.

[0100] The clock tracking providing unit 50, connected to the processing unit 40, is used to provide clock tracking for base stations connected to the first and second bearer networks based on the clock of the first bearer network, the clock of the second bearer network, or the clock signal obtained through the clock crossover mechanism, so as to provide a clock reference source for the base stations.

[0101] The apparatus in this embodiment is capable of the method in Embodiment 1.

[0102] Example 3:

[0103] like Figure 4 As shown, this embodiment provides an electronic device, which includes a memory 200 and a processor 100. The memory 200 stores a computer program. When the processor 100 runs the computer program stored in the memory 200, the processor 100 executes the method for providing a clock reference source for a base station according to Embodiment 1.

[0104] Example 4:

[0105] This embodiment provides a system for providing a clock reference source for a base station. This system is used to implement the method for providing a clock reference source for a base station as described in Embodiment 1. The system includes:

[0106] The primary clock source module and the backup clock source module are respectively located at different access points of the optical transport network;

[0107] The optical transport network module is equipped with path protection function, which is used to transparently transmit multiple clock signals to the downstream aggregation node;

[0108] A clock processing unit, located at the downstream aggregation node, is used to group and select multiple clock signals and generate at least two output clock signals.

[0109] At least two bearer network modules are used to receive the output clock signal and provide a clock reference for the base station;

[0110] A cross-connection protection link is connected between different bearer network modules to provide a backup clock path through a normally functioning bearer network module when the clock input of any bearer network module fails, thereby ensuring the continuity and reliability of the clock reference.

[0111] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method of providing a clock reference source for a base station, characterized by, The method comprises the following steps: introducing a primary clock source at a first node of an OTN network, and introducing a backup clock source at a second node of the OTN network; transmitting the primary clock source and the backup clock source to a third node of the OTN network through a primary line and a backup line independent of each other in the OTN network, so that the third node receives four clock signals; wherein the four clock signals comprise a first primary clock signal transmitted by the primary line, a first backup clock signal transmitted by the primary line, a second primary clock signal transmitted by the backup line, and a second backup clock signal transmitted by the backup line; selecting the first primary clock signal and the first backup clock signal at the third node to generate a first bearer network clock, and simultaneously selecting the second primary clock signal and the second backup clock signal to generate a second bearer network clock; wherein the priority of the first primary clock signal is higher than that of the first backup clock signal, and the priority of the second primary clock signal is higher than that of the second backup clock signal; outputting the first bearer network clock and the second bearer network clock to a first bearer network and a second bearer network respectively, and establishing a clock cross-link mechanism between the first bearer network and the second bearer network; wherein when the first bearer network loses the clock signal received thereby, the clock signal is acquired from the second bearer network through the clock cross-link mechanism, and when the second bearer network loses the clock signal received thereby, the clock signal is acquired from the first bearer network through the clock cross-link mechanism; providing clock tracking for base stations hung under the first bearer network and the second bearer network based on the first bearer network clock, the second bearer network clock, or the clock signal acquired through the clock cross-link mechanism, so as to provide a clock reference source for the base stations.

2. The method of providing a clock reference source for a base station of claim 1, wherein, The primary clock source and the backup clock source are both 1588V2 clock packets.

3. The method of providing a clock reference source for a base station of claim 1, wherein, The first node and the second node are located at different local stations.

4. The method of providing a clock reference source for a base station of claim 1, wherein, The OTN network is in a ring network structure.

5. The method of providing a clock reference source for a base station of claim 1, wherein, The protection mechanism of the primary line and the backup line is optical multiplex section protection (OMSP) or optical line protection (OLP).

6. The method of providing a clock reference source for a base station of claim 1, wherein, The first bearer network clock and the second bearer network clock are respectively output by completely independent clock board cards on the third node, and are transmitted by physical optical fibers different from each other.

7. The method for providing a clock reference source for a base station according to claim 1, wherein a mutual tracking prevention mechanism is arranged between the hung base stations of the first bearer network and the second bearer network.

8. An apparatus for providing a clock reference source for a base station, characterized in that, comprises: a clock source introduction unit configured to introduce a primary clock source at a first node of an OTN network, and introduce a backup clock source at a second node of the OTN network; a clock transmission unit connected with the clock source introduction unit, configured to transmit the primary clock source and the backup clock source to a third node of the OTN network through a primary line and a backup line independent of each other in the OTN network, so that the third node receives four clock signals; The four clock signals include a first master clock signal transmitted by the master line, a first backup clock signal transmitted by the master line, a second master clock signal transmitted by the backup line, and a second backup clock signal transmitted by the backup line. A packet selection unit is connected with the clock transmission unit, configured to select the first master clock signal and the first backup clock signal at the third node to generate a first bearer network clock, and simultaneously select the second master clock signal and the second backup clock signal to generate a second bearer network clock. The priority of the first master clock signal is higher than that of the first backup clock signal, and the priority of the second master clock signal is higher than that of the second backup clock signal. A processing unit is connected with the packet selection unit, configured to output the first bearer network clock and the second bearer network clock to a first bearer network and a second bearer network respectively, and establish a clock cross-link mechanism between the first bearer network and the second bearer network. When the first bearer network loses the received clock signal, the clock signal is acquired from the second bearer network through the clock cross-link mechanism; when the second bearer network loses the received clock signal, the clock signal is acquired from the first bearer network through the clock cross-link mechanism. A clock tracking providing unit is connected with the processing unit, configured to provide clock tracking for base stations hung under the first bearer network and the second bearer network based on the first bearer network clock, the second bearer network clock, or the clock signal acquired through the clock cross-link mechanism, so as to provide a clock reference source for the base stations.

9. An electronic device comprising a memory and a processor, characterized in that The memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes the method for providing a clock reference source for a base station according to any one of claims 1 to 7.

10. A system for providing a clock reference source for a base station, characterized by The system is used to implement the method for providing a clock reference source for a base station according to any one of claims 1 to 7, and the system comprises: A master clock source module and a backup clock source module are respectively arranged at different access points of an optical transport network. An optical transport network module is configured with a path protection function, and is used to transmit multiple clock signals to a network node. A clock processing unit is arranged at the network node, and is used to group and select the multiple clock signals and generate at least two output clock signals. At least two bearer network modules are used to receive the output clock signals and provide a clock reference for a base station. A cross-link protection link is connected between different bearer network modules, and is used to provide a backup clock path through a normally working bearer network module when the clock input of any bearer network module is invalid, so as to ensure the continuity and reliability of the clock reference.

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