Train super cell non-signaling handover method, system and device

Abstract

The application relates to a train super cell non-signaling switching method, system and device, the method comprising: registering multiple gNodeBs to a central beam controller to aggregate into one super cell; obtaining the position and speed of the train at the current time, predicting the position at the next time based on the position and speed, calculating the target TRP corresponding to the position, and issuing a beamforming instruction to the target TRP; when the train enters the area covered by the target TRP, automatically switching the user equipment physical layer from the original TRP to the target TRP in a non-signaling manner. The application reduces the switching interruption delay to sub-millisecond level by constructing the architecture of the central beam controller plus the super cell, and adopts the non-signaling beam handover mechanism in the super cell, so that the lossless continuous transmission of the service is realized; the application introduces the beam pre-activation mechanism based on the train position prediction, and eliminates the performance loss caused by the Doppler frequency offset and the beam mismatch.

Description

Technical Field

[0001] This invention relates to the field of communications, and specifically to a signaling-free handover method, system, and device for a train supercell. Background Technology

[0002] In the 5G Standalone (SA) high-speed rail private network scenario, ensuring service continuity for users on trains traveling at speeds of 350 km / h and above is a core challenge for operators. Existing technologies have proposed various solutions from different dimensions, aiming to "reduce the number of handovers, reduce handover latency, and improve handover success rate." Based on a comprehensive search of patents, academic papers, and public information, existing technologies can be summarized into the following five categories, but none of them have broken through the traditional paradigm of using cells as the basic mobility management unit, and have failed to completely solve the signaling storms and millisecond-level service interruptions in the high-speed rail scenario.

[0003] I. Parameter Tuning and Handover Strategy Optimization: This type of technology focuses on optimizing the parameters or algorithms of measurement, decision-making, and execution in the traditional handover process. It is a "modified" solution, and its underlying layer still relies on the standard Xn interface signaling interaction process (such as handover request, confirmation, and reconfiguration).

[0004] II. Static Network Planning and Engineering Design: This type of technology focuses on the planning of engineering parameters in the early stages of network construction. By optimizing static methods such as base station site selection, antenna parameters, and cell merging, it improves coverage continuity and thus passively reduces the number of handovers.

[0005] III. Terminal-side avoidance and network selection: This type of technology starts from the user equipment (UE) side, and avoids handover problems by identifying network status or user scenarios and adopting a "dimensionality reduction compatibility" strategy.

[0006] IV. Vehicle-to-ground communication and backhaul architecture: This type of technology focuses on solving the problem of backhaul link continuity for onboard base stations or users during train movement, rather than the switching of the air interface wireless access layer.

[0007] V. Protocol Standard Evolution and Mechanism Optimization: This type of material mainly interprets the enhanced features of 3GPP standards for high-speed mobile scenarios, which are still optimizations within the established protocol framework.

[0008] Although existing technologies have alleviated communication pressure in high-speed rail scenarios to some extent through supercell merging, parameter optimization, and network planning, analysis of retrieved data reveals the following inherent and insurmountable defects: Internal handover signaling cannot be eliminated, leading to service interruptions and latency jitter: Existing supercell technology is essentially a static aggregation of physical resources or a merging based on the BBU backplane. When user equipment (UE) moves between different transmit / receive points (TRPs) within a supercell, the existing architecture still needs to trigger Xn interface signaling interactions within or between base stations to execute the complete RRC reconfiguration process. This mechanism inevitably results in service interruptions and latency jitter of tens of milliseconds with each handover, failing to meet the stringent requirements of "zero-perception" handover for real-time interactive services (such as high-definition video conferencing and remote control) in high-speed rail scenarios.

[0009] Beam management lags behind and struggles to adapt to ultra-high-speed mobility: Existing technologies primarily rely on channel state information (CSI) or measurement reports periodically reported by the UE for beam adjustment. In a high-speed operating environment of 350 km / h, this reactive "measure first, adjust later" mechanism suffers from severe time delays, causing the beam to fail to align with the train in advance. This results in beam pointing mismatch and a sharp drop in signal quality index (SINR), severely impacting transmission rate and link stability.

[0010] Distributed control architecture leads to low coordination efficiency: In the existing network architecture, handover decisions and beam management are scattered across various independent gNodeBs (core base stations of the 5G NR radio access network, or 5G base stations for short). The lack of a central control entity capable of overseeing the entire network makes it impossible to pre-schedule resources across multiple TRPs (transmitter / receiver points) based on the train's global operating trajectory. This decentralized control model results in inefficient resource allocation, making it difficult to achieve millisecond-level seamless beam handover across sites, and is prone to signaling storms. Summary of the Invention

[0011] This invention provides a signaling-free handover method, system, and device for train supercells to solve at least one of the above-mentioned technical problems.

[0012] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A signaling-free handover method for a train supercell, comprising: Multiple gNodeBs are deployed along the railway line and registered with the central beam controller to be aggregated into a supercell that broadcasts unified core parameters to the outside world; each gNodeB contains one or more TRPs. The system acquires the current position and speed of the train in real time, predicts the position of the train at the next moment, calculates the target TRP corresponding to the position, and sends beamforming instructions to the target TRP so that the target TRP can complete beam configuration before the train arrives. When the target TRP and the original TRP corresponding to the current location of the train are located in the same supercell, and the train enters the area covered by the target TRP, the physical layer of the user equipment is automatically switched from the original TRP to the target TRP in a signalless manner.

[0013] Based on the above technical solution, the present invention can be further improved as follows.

[0014] Furthermore, the core parameters include cell ID, physical cell identifier, and tracking code area.

[0015] Furthermore, the method for obtaining the train's current position and speed is as follows: The train's current position and speed are obtained using the train's onboard terminal and are periodically reported to the central beam controller via the NR-Uu interface.

[0016] Furthermore, the method for obtaining the train's current position and speed is as follows: The central beam controller is connected to the railway signaling system to directly obtain the current position and speed of the train collected by the railway signaling system.

[0017] Furthermore, the train's position at the next moment is predicted as follows: Using a pre-set trajectory model, combined with the train's current position and speed, the position of the train at the next moment is predicted.

[0018] Furthermore, the beamforming commands include horizontal azimuth angle, vertical downtilt angle, polarization direction, and beamwidth.

[0019] Furthermore, the signaling-free mode specifically means: not triggering any Xn interface signaling, not performing RRC reconfiguration, not migrating the PDCP context, and not retransmitting at the MAC / RLC layer.

[0020] Furthermore, multiple supercells are deployed along the railway line; the signalless handover method for train supercells also includes: When the train is about to leave the current supercell, the central beam controller of the current supercell actively initiates a standard Xn handover procedure with the 5G core network to switch the physical layer of the user equipment to the next supercell.

[0021] Based on the above-mentioned signalless handover method for train supercells, the present invention also provides a signalless handover system for train supercells.

[0022] A train supercell signalless handover system, applied to the train supercell signalless handover method as described above, includes: a supercell construction module and a central beam controller; The supercell construction module is used to deploy multiple gNodeBs along the railway line and register the multiple gNodeBs with the central beam controller to aggregate them into a supercell that broadcasts unified core parameters to the outside world; wherein, each gNodeB contains one or more TRPs; The central beam controller is used to acquire the current position and speed of the train in real time, predict the position of the train at the next moment, calculate the target TRP corresponding to the position, and issue beamforming instructions to the target TRP so that the target TRP completes beam configuration before the train arrives. When the target TRP and the original TRP corresponding to the current position of the train are located in the same supercell, and the train enters the area covered by the target TRP, the user equipment physical layer is automatically switched from the original TRP to the target TRP in a signalless manner.

[0023] Based on the above-mentioned signalless handover method for train supercells, the present invention also provides a signalless handover device for train supercells.

[0024] A train supercell signalless handover device includes a processor, a memory, and a computer program stored in the memory. When the computer program is executed by the processor, it implements the train supercell signalless handover method as described above.

[0025] The beneficial effects of this invention are as follows: In the train supercell signalless handover method, system, and device of this invention, by constructing a central beam controller plus supercell architecture, a signalless beam handover mechanism is adopted within the supercell. This allows users to move between different TRPs within the supercell without triggering Xn interface signaling interaction and RRC reconfiguration process, thereby reducing handover interruption latency to sub-millisecond level and achieving lossless continuous transmission of services. At the same time, this invention introduces a beam pre-activation mechanism based on train position prediction, enabling the target TRP to complete beamforming configuration in advance, ensuring that the signal is immediately aligned when the train arrives, eliminating performance losses caused by Doppler frequency offset and beam mismatch. In addition, this invention uses an independent central beam controller to uniformly manage TRP resources along the line, realizing a paradigm shift from "distributed cell handover" to "centralized beam scheduling," improving the collaborative efficiency and reliability of mobility management in high-speed rail scenarios. Attached Figure Description

[0026] Figure 1 This is a flowchart of a signalless handover method for a train supercell according to the present invention; Figure 2 This is a schematic diagram of the logical structure of a supercell; Figure 3 This diagram illustrates the logical location and interface relationship of the central beam controller within the network. Figure 4 Timing diagram for beam prediction and pre-activation; Figure 5 This is a schematic diagram comparing the signalless handover of the present invention with traditional handover; Figure 6 This is a structural block diagram of a train supercell signalless handover device according to the present invention. Detailed Implementation

[0027] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0028] like Figure 1 As shown, a signaling-free handover method for a train supercell includes: S1, deploy multiple gNodeBs along the railway line and register the multiple gNodeBs with the central beam controller to aggregate them into a supercell that broadcasts unified core parameters to the outside world; wherein, each gNodeB contains one or more TRPs; S2, real-time acquisition of the current position and speed of the train, prediction of the train's position at the next moment, calculation of the target TRP corresponding to the position, and issuance of beamforming command to the target TRP so that the target TRP completes beam configuration before the train arrives; S3, when the target TRP and the original TRP corresponding to the current location of the train are located in the same supercell, and the train enters the area covered by the target TRP, the physical layer of the user equipment is automatically switched from the original TRP to the target TRP in a signalless manner.

[0029] The present invention proposes a novel three-in-one scheme of "supercell + central beam controller (CBC) + location prediction-based beam pre-activation" for a train supercell handover method. This scheme represents a paradigm shift at the network architecture level and can overcome the shortcomings of existing technologies, such as high signaling overhead, delayed beam response, and decentralized control.

[0030] The steps of the method of the present invention will be described in detail below.

[0031] S1 is the step in constructing a supercell. In this step, N (N is a preset value) physical gNodeBs (each containing 1-2 TRPs) are deployed along the railway line. All gNodeBs register with the Central Beam Controller (CBC) and are aggregated into a single supercell. This supercell broadcasts a unified cell ID (e.g., 9999), Physical Cell Identifier (PCI), and Tracking Area Code (TAC) to the outside world, allowing user equipment to perceive only a single cell entity on the network side, and the RRC connection remains unchanged throughout the entire supercell coverage area.

[0032] Figure 2 This is a schematic diagram of the logical structure of a supercell. Multiple physical gNodeBs (gNodeB1 to gNodeBN) are deployed along the railway line, each gNodeB containing one or more TRPs. These gNodeBs are physically independent, but logically aggregated into a single supercell by a central beam controller, broadcasting a unified Cell ID (e.g., 9999), PCI, and TAC. User equipment sees only one cell on the network side, regardless of which TRP it serves under, and the RRC connection remains unchanged. A standard handover to the next supercell is only triggered when the train leaves the area enclosed by the dashed box (i.e., the supercell boundary). The originality of this design lies in redefining the cell boundary—from a physical site boundary to a logical service domain boundary, fundamentally eliminating frequent internal handovers. Implementing the above logical structure only requires upgrading the existing base station software to support CBC registration, without any hardware modifications, making it highly practical. Figure 2 It intuitively demonstrates the topological abstraction of "multiple physical points and a single logical point," which is a prerequisite for eliminating internal switching.

[0033] Figure 3 This diagram illustrates the logical location and interface relationships of the Central Beam Controller (CBC) within the network. In the 5G SA core network, a Central Beam Controller (CBC) is deployed, logically located near the User Plane Function (UPF) or on the Multi-Access Edge Computing (MEC) platform to reduce control latency. The CBC connects to the transmit and receive points (TRP_1 to TRP_N) in all physical gNodeBs along the railway line via a southbound interface (e.g., based on Open Fronthaul or a custom API). Each TRP is responsible for local coverage but no longer makes independent handover decisions; user equipment on the train always maintains a single RRC connection with the supercell, which broadcasts a unified Physical Cell Identifier (PCI) and Tracking Area Code (TAC) to the outside world, hiding the internal multi-TRP structure; the CBC interacts with both the AMF and UPF of the 5G core network: when a train enters or leaves the coverage area of ​​the supercell, the CBC notifies the AMF to trigger a standard Xn handover; during normal operation, the CBC only manages beam scheduling and does not involve core network signaling. The key to this architecture lies in centralizing traditional distributed handover control and reducing mobility management from the "cell level" to the "beam level," thereby eliminating internal signaling. User equipment always maintains a single RRC connection with the supercell.

[0034] In other embodiments, the centralized central beam controller can be replaced with a distributed cooperative control architecture: instead of a separate central beam controller (CBC), a distributed cooperative mechanism is used, where each TRP along the line shares train position prediction information through a lightweight interface (such as X2-lite or a private interface). Implementation logic: The source TRP predicts the target TRP based on the train position and directly notifies the target TRP to pre-activate the beam in advance. Once the target TRP is ready, it enters a standby state. Consistent effect: Although the control logic is distributed across various nodes, the effects of "beam pre-activation" and "no signaling physical layer switching" are still achieved, thus reducing control plane latency.

[0035] S2 refers to the steps of acquiring train position and speed, as well as beam prediction and pre-activation based on the motion model.

[0036] During the process of acquiring train position and speed, the central beam controller obtains the real-time status of the train through one of the following two methods: Method 1: Obtain the current position and speed of the train using the train's onboard terminal, and periodically report it to the central beam controller via the NR-Uu interface; Method 2: Connect the central beam controller to the railway signaling system (such as CTCS-3) to directly obtain the current position and speed of the train collected by the railway signaling system (accuracy up to the meter level, update cycle ≤200ms).

[0037] The train's current position and speed are the basic inputs for subsequent beam prediction.

[0038] In the process of beam prediction and pre-activation based on the motion model, the central beam controller uses a uniform linear motion model (or a more complex trajectory model) and, combined with the current position and velocity at time t, predicts the position the train will reach at time t+Δt. Subsequently, the central beam controller calculates the optimal service TRP (denoted as TRP_target, i.e., the target TRP) corresponding to that position and sends beamforming instructions to TRP_target Δt in advance, including: Horizontal azimuth, vertical tilt, polarization, and beamwidth.

[0039] Upon receiving the instruction, TRP_target immediately completes beam configuration and enters a "pre-activated" standby state.

[0040] Figure 4 This is a timing diagram for beam prediction and pre-activation. Figure 4This describes how CBC (Cyber-Band Control) performs beam pre-activation based on train motion. The horizontal axis represents time, marked from t0 to t5. At time t1, CBC obtains the train's current position (e.g., via GPS or railway signaling system), combines it with speed, and uses a uniform linear model to predict the train's arrival at its new position at time t3. Therefore, at time t2 (i.e., Δt = 100ms in advance), CBC sends beamforming commands to the TRP_B (Train Protection System) to be served, including parameters such as azimuth, downtilt, and polarization direction, completing beam pre-activation. By time t3, the train actually enters the TRP_B coverage area, the beam is aligned, and zero-misalignment handover is achieved. The key to this mechanism is shifting beam management from "reactive" to "predictive," solving the beam mismatch problem caused by the feedback lag of traditional CSI (Train Signaling System) at high speeds. Its practicality lies in the fact that Δt can be dynamically adjusted according to speed (e.g., Δt = 100ms at 350km / h, Δt = 70ms at 250km / h), ensuring universality. Figure 4 This explains the closed-loop timing mechanism of prediction-preactivation-service to ensure zero-accuracy switching.

[0041] In other embodiments, the entity responsible for beam prediction and triggering can be changed from the "network side (CBC)" to the "terminal side (UE)". The implementation logic is as follows: the user equipment predicts its own trajectory based on GNSS (Global Navigation Satellite System) or inertial sensors, and broadcasts its "future position" or "expected beam requirements" to neighboring TRPs via NR Sidelink (direct communication) or the uplink control channel. The effect is consistent: after receiving the prediction information from the user equipment, neighboring TRPs pre-configure the beam. This also achieves spatiotemporal matching between the beam and the train's position. Although it increases terminal complexity, it achieves a similar seamless switching effect.

[0042] In other embodiments, the "uniform linear motion model" used to calculate the train position in CBC can be replaced with an "AI / deep learning model"; implementation logic: use deep learning models such as LSTM (Long Short-Term Memory Network) and Transformer to replace the traditional geometric kinematic model; consistent results: input historical position data, and the AI ​​model outputs the predicted value of the future train position; although the algorithm core is different, its external function (position prediction) and ultimate purpose (trigger beam pre-configuration) are consistent with the present invention.

[0043] In other embodiments, the unicast pre-activated data forwarding mechanism can be replaced by a bicast redundant data forwarding mechanism. Alternative description: In a very few scenarios with extremely high reliability requirements and sufficient bandwidth, bicasting technology can be combined. Implementation logic: While beam pre-activation is in progress, the core network or source node pre-issues a data buffer to the target TRP. Although this increases the backhaul load, combined with signaling-free beam switching, it can further ensure zero data loss.

[0044] S3 is the step executed without signaling beam handover. When the target TRP and the original TRP corresponding to the train's current location are located in the same supercell, and the train enters the area covered by the target TRP, the user equipment physical layer automatically switches from the original TRP (TRP_source) to TRP_target. Since the beams have been pre-aligned, there is no sudden drop in signal quality; this process does not trigger any Xn interface signaling, does not perform RRC reconfiguration, does not migrate the PDCP context, and does not involve retransmission at the MAC / RLC layer. The user equipment only senses the change in signal source, and service continuity is not affected; the handover interruption latency can be compressed to <0.5ms.

[0045] Figure 5 This is a schematic diagram comparing the signalless handover of the present invention with traditional handover. Figure 5 The left side shows the traditional Xn handover: source gNodeB → HO Request → target gNodeB → HO Ack → RRC reconfiguration, with a latency >30ms; the right side shows the signaling-free handover of this invention: the CBC pre-configures the TRP_B beam, and the user equipment directly switches at the physical layer without any signaling interaction, with a latency <0.5ms. In traditional handover, when the user equipment approaches the cell boundary, the source gNodeB needs to send a handover request (HO Request) to the target gNodeB through the Xn interface. The latter prepares resources and sends back an acknowledgment (HO Ack). The entire process involves RRC reconfiguration, data forwarding, context migration, and other steps, with a typical latency >30ms, which can easily lead to service interruption. In the signaling-free handover of this invention, the user equipment always belongs to the same logical supercell, and its physical layer serving beam is seamlessly transferred from TRP_A to TRP_B. This process is pre-calculated and the beam parameters are issued by the CBC. The user equipment only senses the change in signal source, and there are no retransmissions or state changes at the MAC / RLC / PDCP layers. The handover latency can be compressed to the sub-millisecond level (<0.5ms). This invention reduces the handover operation from the network layer to physical layer beam scheduling, completely bypassing the interaction between the Xn interface and the core network, and retaining only one boundary handover for cross-supercell movement.

[0046] This invention also includes S4: Supercell boundary handover. Multiple supercells are deployed along the railway line; the train supercell handover method without signaling further includes: When the train is about to leave the current supercell (approaching the coverage edge of the current supercell, for example, less than 5km from the boundary), the central beam controller of the current supercell actively initiates a standard Xn handover procedure with the 5G core network to switch the user equipment physical layer to the next supercell. Throughout the entire train journey, a traditional handover only occurs once at the supercell boundary, and the handover between internal TRPs is completely signalless.

[0047] The method of the present invention will be illustrated below with specific examples.

[0048] Taking a real-world engineering scenario (Fuzhou section of the Fuzhou-Xiamen High-Speed ​​Railway) as an example: The supercell has a coverage length of 15km and includes 8 gNodeBs (a total of 16 TRPs). The train operates at a speed of 350 km / h; The central beam controller updates the position prediction every 200ms; Beam pre-activation lead Δt = 100ms (corresponding to approximately 9.7 meters of lead distance); The central beam controller is deployed on the MEC platform, with a control latency of <5ms.

[0049] Actual test results: Interruption delay between internal TRPs is <0.5ms (traditional solution >30ms); PRB utilization remained stable below 20%, with no sudden congestion. The video service stuttering rate is 0%, and the voice MOS score is ≥4.2.

[0050] This embodiment demonstrates that the method of the present invention has high practicality and deployability, requiring only an upgrade of the existing base station software to support the registration of the central beam controller and remote beam configuration, without the need for additional hardware.

[0051] Based on the above-mentioned signalless handover method for train supercells, the present invention also provides a signalless handover system for train supercells.

[0052] A train supercell signalless handover system, applied to the train supercell signalless handover method as described above, includes: a supercell construction module and a central beam controller; The supercell construction module is used to deploy multiple gNodeBs along the railway line and register the multiple gNodeBs with the central beam controller to aggregate them into a supercell that broadcasts unified core parameters to the outside world; wherein, each gNodeB contains one or more TRPs; The central beam controller is used to acquire the current position and speed of the train in real time, predict the position of the train at the next moment, calculate the target TRP corresponding to the position, and issue beamforming instructions to the target TRP so that the target TRP completes beam configuration before the train arrives. When the target TRP and the original TRP corresponding to the current position of the train are located in the same supercell, and the train enters the area covered by the target TRP, the user equipment physical layer is automatically switched from the original TRP to the target TRP in a signalless manner.

[0053] It should be noted that the specific functions of the supercell construction module and the central beam controller in the train supercell signalless handover system of the present invention are described in the specific steps of the train supercell signalless handover method of the present invention, and will not be repeated here.

[0054] Based on the above-mentioned signalless handover method for train supercells, the present invention also provides a signalless handover device for train supercells.

[0055] like Figure 6 As shown, a train supercell signalless handover device includes a processor, a memory, and a computer program stored in the memory. When the computer program is executed by the processor, it implements the train supercell signalless handover method as described above.

[0056] In one optional embodiment, a train supercell signalless handover device is provided, such as... Figure 6 As shown. Figure 6 The train supercell signalless handover device shown includes a processor and a memory. The processor and memory are connected, for example, via a bus. Optionally, the train supercell signalless handover device may further include a transceiver, which can be used for data interaction between the train supercell signalless handover device and other electronic devices, such as sending and / or receiving data. It should be noted that in practical applications, the transceiver is not limited to one unit, and the structure of this train supercell signalless handover device does not constitute a limitation on the embodiments of the present invention.

[0057] The processor can be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLC (Programmable Logic Controller), a FPGA (Field Programmable Gate Array), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this invention. The processor can also be a combination that implements computational functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0058] A bus can include a pathway for transmitting information between the aforementioned components. The bus can be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, Figure 6 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0059] The memory may be ROM (Read Only Memory) or other types of static storage devices capable of storing static information and instructions, RAM (Random Access Memory) or other types of dynamic storage devices capable of storing information and instructions, or EEPROM (Electrically Erasable Programmable Read Only Memory), CD-ROM (Compact Disc Read Only Memory) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited to these.

[0060] The memory stores application code (computer program) that executes the present invention, and its execution is controlled by a processor. The processor executes the application code stored in the memory to implement the content shown in the foregoing method embodiments.

[0061] Among them, the signaling-free handover equipment in the train super cell can also be a terminal device. The terminal device can be any device that can install applications, including at least one of smartphones, tablets, laptops, desktop computers, smart speakers, smartwatches, smart TVs, and smart in-vehicle devices.

[0062] It should be noted that, Figure 6 The train supercell signalless handover device shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of the present invention.

[0063] The present invention provides a signaling-free handover method, system, and equipment for train supercells, which has the following characteristics and effects: The construction and unified identification management of super cells: Multiple physical gNodeBs (RRUs / TRPs) along the railway line are logically aggregated into a single "super cell". This super cell broadcasts a unified Cell ID, PCI (Physical Cell Identifier) ​​and TAC (Tracking Area Code) to the outside world. This mechanism enables user equipment to maintain only one RRC connection throughout the entire coverage area, completely hiding the physical topology of multiple TRPs inside from the network side, and solving the problem of frequent signaling interaction caused by the existence of physical cell boundaries in traditional solutions.

[0064] The centralized control architecture based on the Central Beam Controller (CBC) introduces an independent logical entity—the Central Beam Controller (CBC)—deployed at the MEC or near the UPF. The CBC acts as a unified dispatch center, responsible for obtaining train positions, predicting beams, and issuing commands. This is fundamentally different from the existing architectures that rely on distributed gNodeBs for independent decision-making or only interact through the Xn interface, achieving decoupling between the control plane and the user plane and centralized scheduling.

[0065] The beam pre-activation mechanism based on position prediction (the core of signaling-free handover): Utilizing the train's precise position / speed, the CBC predicts the train's future position through a motion model and issues beamforming commands (including azimuth, downtilt, polarization, etc.) to the target TRP in advance; the target TRP completes "beam pre-activation" before the train arrives; when the user equipment physical layer detects a signal change, it directly switches to the activated beam. This process does not trigger any Xn interface signaling, does not perform RRC reconfiguration, and does not migrate the PDCP context. It only achieves service source handover through automatic beam handover at the physical layer, compressing latency to sub-millisecond levels.

[0066] The hierarchical mobility management strategy of "boundary handover" and "internal relay" clearly distinguishes the processing logic between "inside the supercell" and "supercell boundary"; internal mobility is completely handled by the CBC through beam scheduling (no signaling); only when the train leaves the coverage area of ​​the entire logical supercell will the CBC notify the AMF to trigger a standard Xn handover procedure; this strategy of "no signaling inside, one handover at the boundary" is the key to achieving low overhead under high frequency mobility in this invention.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A signalless handover method for a train supercell, characterized in that, include: Multiple gNodeBs are deployed along the railway line and registered with the central beam controller to be aggregated into a supercell that broadcasts unified core parameters to the outside world; each gNodeB contains one or more TRPs. The system acquires the current position and speed of the train in real time, predicts the position of the train at the next moment, calculates the target TRP corresponding to the position, and sends beamforming instructions to the target TRP so that the target TRP can complete beam configuration before the train arrives. When the target TRP and the original TRP corresponding to the current location of the train are located in the same supercell, and the train enters the area covered by the target TRP, the physical layer of the user equipment is automatically switched from the original TRP to the target TRP in a signalless manner.

2. The signalless handover method for train supercells according to claim 1, characterized in that, The core parameters include cell ID, physical cell identifier, and tracking code area.

3. The signalless handover method for train supercells according to claim 1, characterized in that, The method for obtaining the current position and speed of the train is as follows: The train's current position and speed are obtained using the train's onboard terminal and are periodically reported to the central beam controller via the NR-Uu interface.

4. The signalless handover method for train supercells according to claim 1, characterized in that, The method for obtaining the current position and speed of the train is as follows: The central beam controller is connected to the railway signaling system to directly obtain the current position and speed of the train collected by the railway signaling system.

5. The signalless handover method for train supercells according to claim 1, characterized in that, Predicting the train's position at the next moment, specifically: Using a pre-set trajectory model, combined with the train's current position and speed, the position of the train at the next moment is predicted.

6. The signalless handover method for train supercells according to claim 1, characterized in that, The beamforming commands include horizontal azimuth, vertical downtilt, polarization direction, and beamwidth.

7. The signalless handover method for train supercells according to claim 1, characterized in that, The signalless mode specifically refers to: not triggering any Xn interface signaling, not performing RRC reconfiguration, not migrating the PDCP context, and not retransmitting at the MAC / RLC layer.

8. The signalless handover method for train supercells according to claim 1, characterized in that, Multiple supercells are deployed along the railway line; the signalless handover method for train supercells also includes: When the train is about to leave the current supercell, the central beam controller of the current supercell actively initiates a standard Xn handover procedure with the 5G core network to switch the physical layer of the user equipment to the next supercell.

9. A signalless handover system for a train supercell, characterized in that, The method for signalless handover of a train supercell as described in any one of claims 1 to 8 includes: a supercell construction module and a central beam controller; The supercell construction module is used to deploy multiple gNodeBs along the railway line and register the multiple gNodeBs with the central beam controller to aggregate them into a supercell that broadcasts unified core parameters to the outside world; wherein, each gNodeB contains one or more TRPs; The central beam controller is used to acquire the current position and speed of the train in real time, predict the position of the train at the next moment, calculate the target TRP corresponding to the position, and issue beamforming instructions to the target TRP so that the target TRP completes beam configuration before the train arrives. When the target TRP and the original TRP corresponding to the current position of the train are located in the same supercell, and the train enters the area covered by the target TRP, the user equipment physical layer is automatically switched from the original TRP to the target TRP in a signalless manner.

10. A signaling-free handover device for a train supercell, characterized in that, The system includes a processor, a memory, and a computer program stored in the memory, wherein the computer program, when executed by the processor, implements the train supercell signalless handover method as described in any one of claims 1 to 8.

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