5G-TSN high-precision time synchronization method based on dynamic compensation

Abstract

The invention relates to a 5G-TSN high-precision time synchronization method based on dynamic compensation, and belongs to the technical field of wireless communication and industrial network convergence. In order to solve the problem that the time synchronization precision is influenced by propagation time delay non-stationary random jitter caused by multipath fading and terminal mobility during 5G system air interface transmission of a TSN synchronization message, the method comprises the following steps: acquiring a time advance TA and a round trip time RTT through dual-mechanism time delay measurement to initialize a dynamic compensation factor; the factor is used for correcting an air interface propagation delay value in real time, a sliding window anomaly detection mechanism is used for dealing with sudden channel fluctuation, and meanwhile a compensation factor periodic updating and emergency calibration process is set. According to the method, the delay jitter of the wireless air interface is effectively inhibited, the clock synchronization precision and the system robustness of the TSN node under the 5G-TSN network are remarkably improved, and the strict requirement of an industrial control scene for microsecond-level synchronization is met.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication and industrial network integration technology, and relates to a 5G-TSN high-precision time synchronization method based on dynamic compensation. Background Technology

[0002] The rapid development of the Industrial Internet of Things (IIoT) has placed extremely high demands on time-critical communication. Achieving high-precision time synchronization between network devices is fundamental to ensuring collaborative operation and real-time control of industrial control systems. Time-Sensitive Networking (TSN), as a key technology, can provide low-latency, high-reliability, and real-time communication services while maintaining good compatibility with standard Ethernet. This compatibility allows time-critical and non-critical data streams to coexist and be transmitted within the network.

[0003] Traditionally, Time-Sensitive Networking (TSN) relies on Industrial Ethernet to achieve microsecond-level synchronization and deterministic transmission. However, this approach falls short in coverage when facing mobile devices, wide-area facilities, and complex industrial environments. Meanwhile, 5G, with its ultra-reliable low-latency communication and enhanced mobile broadband characteristics, makes it possible to extend the hard real-time capabilities of TSN to the radio domain, thereby building comprehensive deterministic communication coverage.

[0004] In the convergence of 5G and Time-Sensitive Networking (TSN) in networking schemes, the 5G system is typically treated as a virtual TSN bridge. This scheme relies on high-precision time synchronization to ensure deterministic end-to-end transmission. However, its air interface transmission latency is susceptible to multipath fading and terminal mobility, exhibiting non-stationary random jitter, which poses a significant challenge to time synchronization accuracy. Therefore, a dynamic compensation mechanism is urgently needed to address these unstable factors.

[0005] like Figure 1As shown, in a typical 5G and Time-Sensitive Network (TSN) time synchronization architecture, there are two parallel synchronization processes. The first is the synchronization process within the 5G system itself, where the 5G system master clock distributes the time reference. The second is the synchronization process within the TSN domain, where the TSN master clock distributes the time reference to other slave clocks via the IEEE 802.1AS protocol. In this architecture, the 5G system acts as a logical bridge, and its edge TSN converters, including network-side and user equipment-side TSN converters, are responsible for processing synchronization messages and recording key timestamps. By synchronizing the TSN master clock to the 5G system base station, inter-system latency errors can be eliminated, laying the foundation for achieving microsecond-level synchronization accuracy. Nevertheless, the dynamic latency jitter generated during the wireless air interface transmission of synchronization messages remains a core challenge for improving synchronization accuracy under current technological conditions. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a 5G-TSN high-precision time synchronization method based on dynamic compensation.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A high-precision time synchronization method for 5G-TSN based on dynamic compensation includes a dual-mechanism delay measurement and compensation factor initialization step, a real-time dynamic delay compensation step, a compensation factor periodic update step, and a sliding window anomaly detection and emergency calibration step. The dual-mechanism delay measurement and compensation factor initialization step initializes the dynamic compensation factor α based on time advance (TA) and round trip time (RTT) measurements. The real-time dynamic delay compensation step uses the dynamic compensation factor α to correct the... TA The calculated air interface propagation delay yields the compensated delay value. D i ; The periodic update step of the compensation factor periodically updates the dynamic compensation factor α; The sliding window anomaly detection and emergency calibration step triggers emergency calibration when an abnormal air interface propagation delay is detected.

[0008] Furthermore, the basis TA The air interface propagation delay measurement includes the fifth-generation new radio base station (5G Node B, gNB) at time... t1. Transmit a Synchronization Signal Block (SSB) at time [time]. t 2. Receive the SSB and calculate TA value, TA = t 2- t 1.

[0009] Furthermore, the basis RTT The air interface propagation delay measurement includes the UE at time [time]. t 1. Send a PTP Delay Request (Pdelay_Req) ​​message to the gNB. The gNB will then... t 2. Receive the Pdelay_Req and record the timestamp, gNB at time... t 3. Send a PTP Delay Response (Pdelay_Resp) message to the UE, carrying a timestamp. t 2. UE at time t 4. Receive the Pdelay_Resp and obtain the timestamp through the PTP Delay Response Follow Up (Pdelay_Resp_Follow_Up) message. t 3. Calculation RTT value, .

[0010] Furthermore, the dynamic compensation factor The calculation formula is: ,in Indicates time-varying frequency drift. Indicates the drift compensation coefficient. This indicates a Channel Quality Indicator (CQI). This represents the channel quality weighting coefficient.

[0011] Furthermore, the compensation delay value D i The calculation formula is: ,in It is based on the current moment TA Calculate the air interface propagation delay value.

[0012] Furthermore, in the compensation factor periodic update step, the update period is a preset time T, and the UE periodically repeats the dual-mechanism delay measurement and compensation factor initialization steps to update the dynamic compensation factor. .

[0013] Furthermore, the sliding window anomaly detection and emergency calibration step includes initializing the sliding window size. W Collection of latency sample sets ,in i Calculate the mean for the current sample number. and standard deviation σ, Dynamic thresholds are generated based on the 3σ criterion. For each sample within the window d i If satisfied If it does, it is marked as an exception.

[0014] Furthermore, when an anomaly is detected, trigger... RTT Remeasurement to update dynamic compensation factor And before the remeasurement is completed, the mean of the three normal samples before the abnormality within the sliding window is used as the temporary delay compensation value.

[0015] Furthermore, the compensation delay value D i The correction field written into the synchronization message is used for downstream clock synchronization.

[0016] Furthermore, the method is applied to a 5G system as a logical TSN bridge, achieving synchronization with the TSN master clock through NW-TT and DS-TT.

[0017] The beneficial effects of this invention are as follows: (1) This invention combines time advance amount TA and round trip time RTT A dual-mechanism measurement approach, incorporating a dynamic compensation factor to correct air interface propagation delay in real time, fundamentally solves the delay jitter problem caused by multipath fading in wireless channels and terminal mobility. This method effectively overcomes the inherent system errors of a single measurement mechanism, making the delay calculation of time synchronization messages transmitted within the 5G system more accurate. This elevates the time synchronization accuracy of the entire 5G and Time-Sensitive Network (TSN) converged network to the microsecond level, meeting the most stringent synchronization requirements of industrial control scenarios.

[0018] (2) The sliding window anomaly detection mechanism adopted in this invention can continuously monitor changes in air interface propagation delay. When a sudden channel fluctuation is detected that causes an anomaly in delay, the system can immediately trigger an emergency calibration process to quickly restore the accurate delay compensation value. This proactive defense mechanism ensures that the time synchronization process can resist sudden interference in complex industrial wireless environments, maintain the long-term stable operation of the system, and avoid equipment misoperation or production interruption that may be caused by synchronization inaccuracies.

[0019] (3) This invention does not use fixed compensation parameters, but instead designs a periodic update mechanism for the compensation factor. This mechanism can dynamically adjust the compensation factor to keep up with the long-term slow changes in terminal mobility and channel conditions, so that the delay compensation value always matches the current actual channel state. This ensures that the time synchronization accuracy will not gradually deteriorate with device movement or environmental changes, and achieves high-precision synchronization in the entire time and space domain.

[0020] (4) High-precision time synchronization is the foundation for end-to-end deterministic transmission in 5G networks as logical time-sensitive network (TSN) bridges. This invention ensures the timing determinism of synchronization messages when traversing the 5G system by accurately compensating for the uncertain delay of the wireless air interface segment, thereby providing a reliable path guarantee for upper-level industrial control applications and strongly supporting the hard requirements for global deterministic connectivity in the context of Industry 4.0.

[0021] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 It is a 5G-TSN time synchronization structure; Figure 2 This is the synchronization process for 5G-TSN; Figure 3 This is a schematic diagram of the overall solution; Figure 4 For based on TA Schematic diagram of the principle of air interface propagation delay calculation; Figure 5 For based on RTT The principle diagram for calculating air interface propagation delay. Detailed Implementation

[0023] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0024] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0025] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0026] In a 5G-TSN network, two distinct synchronization processes operate in parallel. The first is the internal synchronization process within the 5G system, where the same time base is distributed by the 5G base station master clock (5G GM) to achieve time synchronization within the 5G system. The second synchronization process is TSN time synchronization, where the TSN master clock (TSN GM) distributes the time base to other slave clocks via IEEE 802.1AS. Throughout the end-to-end synchronization path, the 5G system is treated as a TSN bridge, with the corresponding ports located at the TSN converters at the edge of the 5G system. The dwell time of the synchronization message in the 5G system is then calculated by recording the timestamps of the synchronization messages transmitted by the external master clock to compensate for link latency. Both the user equipment-side TSN converter (DS-TT) and the network-side TSN converter (NW-TT) support IEEE 802.1AS functions, such as processing gPTP packet messages and recording timestamps. Synchronization of the TSN GM to the 5G base station eliminates clock skew between the 5G and TSN domains, ensuring accurate latency data and guaranteeing microsecond-level synchronization precision. The process of TSN master clock receiving synchronization from 5G base station is as follows: The 5G GM sends time synchronization signals (Sync / Follow_Up messages) to the NW-TT via the PTPv2 protocol. The NW-TT, acting as a boundary clock, receives the 5G GM's time reference and synchronizes with it. The TSN GM connects to the NW-TT's physical port via wired Ethernet, is configured in PTP slave clock mode, and aims to synchronize with the 5G GM. The NW-TT, acting as the PTP master clock (relative to the TSN GM), sends a PTP Announce message to the TSN GM, announcing the 5G GM's time reference information. The TSN GM receives the Announce message from the NW-TT and compares its local clock parameters with those of the 5G GM. Since the 5G GM is typically synchronized via GNSS, it has higher priority than the TSN GM's local clock, and the TSN GM selects the 5G GM as its master clock. The NW-TT periodically sends Sync and Follow_Up messages, containing the 5G GM's transmission timestamp. The TSN GM synchronizes with the 5G GM based on the received synchronization message information.

[0027] The process of a synchronization message passing through a 5G network: When a synchronization message sent by the TSN master clock enters the 5G network, it first reaches the NW-TT. Upon receiving the synchronization message, the NW-TT records the entry timestamp at the physical layer and corrects its own clock to synchronize with the TSN master clock. It then encapsulates the synchronization message into a 5G GTP-U data packet, retaining the original PTP field, and transmits it to the DS-TT via the 5G network. During transmission, it records the core network dwell time and air interface propagation time of the GTP-U data packet carrying the synchronization message and adds this information to the Correction Field of the synchronization message. Upon receiving the data packet, the DS-TT decapsulates the GTP-U data packet and extracts the corrected PTP message. The DS-TT calculates the clock deviation from the GM based on the Correction Field and the local timestamp, corrects its own clock to synchronize with the TSN master clock, and then sends the synchronization message to the next hop, recording the timestamp of the synchronization message leaving the 5G network and placing it in the Follow_Up message.

[0028] Define a clock model as shown in formula (1): (1) in T ( t () is the time on the clock. t The time displayed T 0 is the initial time offset, indicating that at t At time 0, the deviation between the actual clock and the ideal clock. f It is a fixed frequency deviation. It is time-varying frequency drift, which indicates that the clock frequency changes with time. t The dynamically changing part.

[0029] This method proposes a dynamic compensation factor mechanism to improve time synchronization accuracy and adopts a sliding window anomaly detection to deal with sudden situations, thereby solving the impact of wireless air interface delay jitter on synchronization accuracy. It significantly improves the clock synchronization accuracy and robustness of TSN nodes under 5G network, meeting the stringent requirements of microsecond-level synchronization in industrial control scenarios.

[0030] The synchronization process of 5G-TSN is as follows Figure 2As shown, 5G, acting as a logical bridge, does not require time synchronization with external TSN terminals. However, the TSN converter at the 5G edge uses a boundary clock model and needs to synchronize with the TSN master clock in the TSN domain. Thus, the dwell time and propagation delay data can be calculated using the 5G's internal clock and added to the correction field. The synchronization process across 5G logical TSN bridges is illustrated in the figure. The master clock periodically sends synchronization messages with transmission timestamps. 5G bridges supporting PTP will timestamp at both the egress and ingress points, calculating delays and dwell times based on this and adding them to the correction field of the synchronization message, then performing time synchronization between nodes. The product rate ratio (CRR) of the NRRs of all devices in the communication path is also updated.

[0031] The dwell time of synchronization messages on the 5G network T r Export timestamp T eg and entry timestamp T in The difference is calculated as shown in the formula. CRR is used to compensate for the entry timestamps of the master clock and the 5G bridge. T in Frequency offset between clocks.

[0032] (2) (3) Finally, the slave clock will generate a receive timestamp T6 upon receiving the synchronization message, and then calculate the clock error between the master and slave clocks using the information in the synchronization message. T offset As shown in formula (4). The clock error is calculated from the clock. T offset Adjust its own clock to synchronize with the master clock.

[0033] (4) To improve the time synchronization accuracy of 5G-TSN, this invention provides the following: Figure 3 The technical solution shown.

[0034] S1: Dual-mechanism delay measurement and compensation factor initialization This solution primarily addresses compensation for air interface propagation delay. First, it requires obtaining an initial baseline for the air interface propagation delay and calculating the dynamic compensation factor α to provide fundamental parameters for subsequent real-time compensation. TA Systematic error problems in single-mechanism measurements.

[0035] This stage serves as the foundational preparation phase for the entire synchronization scheme, and its core is through... TA and RTTThe dual mechanisms are combined to calculate the dynamic compensation factor α, providing accurate error calibration for subsequent real-time compensation and ensuring high latency calculation accuracy from the moment of synchronous startup.

[0036] Step 1: Based on TA Air-to-ground propagation delay measurement In 5G-TSN network air interface propagation, based on TA Propagation delay compensation methods such as Figure 4 As shown, the core principle is to calculate the one-way air interface propagation delay between the UE and gNB using the downlink reference signal arrival time difference. First, the UE measures the downlink... TA The value, i.e., the downlink reference signal transmitted by the gNB, is calculated by the UE by measuring the arrival time of the signal. TA The value, the calculated TA The value is used as a compensation value for air interface propagation delay.

[0037] The specific process is as follows: gNB follows the 3GPP protocol specifications, in t 1. Periodically transmit downlink SSB synchronization signals; the UE monitors this signal in real time at the receiving end and records the actual arrival time of the signal. t 2; Due to the transmission time of the SSB signal t 1. The system will inform the UE via subsequent MIB / SIB signals. The UE can then calculate the timing advance by using the difference between the arrival time and the transmission time. TA As the initial one-way delay reference.

[0038] (5) Step 2: Based on RTT Air-to-ground propagation delay measurement based on RTT Propagation delay compensation methods such as Figure 5 As shown, a higher-precision average two-way delay is obtained through round-trip message interaction. The UE measures the air interface propagation delay based on Pdelay_Req, Pdelay_Resp, and Pdelay_Resp_Follow_Up.

[0039] The specific process is as follows: UE in t At 1 o'clock, actively send a Pdelay_Req message to the gNB and record the sending timestamp locally. t 1; gNB in t Upon receiving the message at time 2, immediately record the reception timestamp without any processing. t 2; subsequently gNB in t At time 3, a Pdelay_Resp response message is sent to the UE, carrying its own recorded information. t 2 timestamps; UE in tAt time 4, receive Pdelay_Resp and obtain the timestamp of Pdelay_Resp sent by gNB through the subsequent Pdelay_Resp_Follow_Up message. t 3. Ultimately, the UE obtains four timestamps ( t 1. t 2. t 3 and t 4) Measure the air interface propagation delay with gNB RTT : (6) Step 3: Initialization of dynamic compensation factor α This plan is approved. RTT and TA The difference is quantized and stored. TA The system error is introduced, along with dynamic compensation for clock drift and channel quality. Due to... RTT It is a two-way delay mean measurement, which has higher accuracy for air interface propagation delay. TA This is a single-trip time delay measurement, and the measurement result has a certain systematic error. The difference between the two is quantified. TA The system error, combined with clock drift compensation and channel quality compensation, is used to construct a complete compensation factor α, whose mathematical expression is: (7) in This indicates the frequency drift between the local clock and the 5G master clock. This is the drift compensation coefficient, used to quantify the weight of the impact of frequency drift on the compensation factor α; This indicates the channel quality (range: 0~15, the higher the value, the better the channel quality). k This is the channel quality weighting coefficient, representing the weighting per unit. CQI The amount of correction to the compensation factor α due to the change.

[0040] S2: Real-time dynamic delay compensation This stage involves real-time... TA Data acquisition and dynamic α compensation, outputting accurate latency compensation values ​​to ensure that TSN synchronization messages always carry correct latency information, are key steps in achieving microsecond-level synchronization. The compensation factor α, initialized by S1, is used to correct the latency data acquired by the UE in real time. TA The value outputs a precise air interface propagation delay compensation value. D i This information is then written into the Correction Field of the TSN synchronization message to provide a basis for calculating clock skew in NW-TT / DS-TT, thus addressing the impact of real-time jitter in air interface delay on synchronization accuracy. The air interface propagation delay is calculated as follows: Step 1: The UE continuously receives the downlink reference signal (SSB) sent by the gNB and calculates the current time based on formula (5). TA This value captures the real-time dynamic changes in air interface latency. Step 2: Correct the basis using compensation factor α TA Calculate the air interface propagation delay value TA i The time delay compensation value, which is close to the actual air interface propagation, is calculated using formula (8). D i ,offset TA Systematic errors in single-mechanism measurements.

[0041] (8) Step 3: Calculate the air interface propagation delay D i Write the Correction Field in the synchronization message for downstream slave clock synchronization with the master clock.

[0042] S3: Periodic Update of Compensation Factor Over time, changes in the UE's movement, multipath environment, or increased channel fading may cause the initial compensation factor α to become inaccurate, thus affecting synchronization accuracy. Therefore, this stage uses a periodic update mechanism to dynamically adjust the compensation factor α, ensuring it always matches the current channel conditions.

[0043] The specific implementation is as follows: Preset update cycle T The UE starts a periodic timer, triggering an update process every interval T, repeating the process in S1 based on... TA and RTT The air interface propagation delay is measured to obtain the current channel's one-way delay and high-precision two-way delay, and the compensation factor α is recalculated. During the update process, the clock drift rate is considered. f The real-time channel quality (CQI) and α are dynamically corrected using formula (7). If the sliding window detects an abnormality in α, an emergency calibration of S4 is immediately triggered. This mechanism ensures that the air interface delay compensation error is always controlled within a certain range by periodically correcting α, thus guaranteeing long-term synchronization stability.

[0044] S4: Sliding Window Anomaly Detection and Emergency Calibration In real-world industrial settings, unexpected situations may arise that could lead to... TA The value suddenly changes; real-time monitoring in this stage is based on... TA The calculated delay compensation value is triggered immediately upon detecting an anomaly. RTTRemeasurement and emergency α update quickly correct distortion delay compensation values, ensuring synchronization accuracy remains at the microsecond level even under sudden anomalies, thus preventing equipment malfunctions in industrial control scenarios due to synchronization anomalies. The steps for detecting abnormal air interface propagation delay values ​​using a sliding window are as follows: Step 1: Delay data acquisition and sliding window initialization. Collect historical data on air interface propagation delay, and set the sliding window size and sliding step. Step 2: Record the set of delay samples within the current window. The mean μ and standard deviation σ are calculated to reflect the current channel delay benchmark and jitter level; (9) (10) Step 3: Generate dynamic thresholds based on the 3σ criterion For each sample within the window d i If the following conditions are met, it will be marked as an exception: .

[0045] When the sliding window detects based on the 3σ criterion D i In case of an anomaly (such as exceeding the μ±3σ range), immediately skip the periodic update limit and trigger a communication between the UE and gNB. RTT The measurement is retested, and the compensation factor α is updated. Before the measurement is completed, the mean of the three normal samples before the outlier within the sliding window is temporarily used as the time delay compensation value to replace the outlier. D i Calculations are performed to avoid synchronization interruptions caused by missing outliers.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A high-precision time synchronization method for 5G-TSN based on dynamic compensation, characterized in that: It includes a dual-mechanism time delay measurement and compensation factor initialization step, a real-time dynamic time delay compensation step, a compensation factor periodic update step, and a sliding window anomaly detection and emergency calibration step. The dual-mechanism delay measurement and compensation factor initialization steps are based on time advance. TA and round trip time RTT Measure the initial dynamic compensation factor α; The real-time dynamic delay compensation step uses the dynamic compensation factor α to correct the... TA The calculated air interface propagation delay yields the compensated delay value. D i ; The periodic update step of the compensation factor periodically updates the dynamic compensation factor α; The sliding window anomaly detection and emergency calibration step triggers emergency calibration when an abnormal air interface propagation delay is detected.

2. The high-precision 5G-TSN time synchronization method according to claim 1, characterized in that: The basis TA The air interface propagation delay measurement includes the fifth-generation new air interface base station gNB at time... t 1. Send synchronization signal block SSB, user equipment (UE) at time... t 2. Receive the SSB and calculate TA value, TA = t 2- t 1.

3. The high-precision 5G-TSN time synchronization method according to claim 1, characterized in that: The basis RTT The air interface propagation delay measurement includes the UE at time [time]. t 1. Sends a PTP delay request message Pdelay_Req to the gNB. The gNB at time... t 2. Receive the Pdelay_Req and record the timestamp, gNB at time... t 3. Send a PTP delay response message Pdelay_Resp to the UE, carrying a timestamp. t 2. UE at time t 4. Receive the Pdelay_Resp and obtain the timestamp through the PTP delayed response follow message Pdelay_Resp_Follow_Up. t 3. Calculation RTT value, .

4. The high-precision 5G-TSN time synchronization method according to claim 1, characterized in that: The dynamic compensation factor The calculation formula is: ,in Indicates time-varying frequency drift. Indicates the drift compensation coefficient. Indicates Channel Quality Indicator (CQI). This represents the channel quality weighting coefficient.

5. The high-precision 5G-TSN time synchronization method according to claim 1, characterized in that: The compensation delay value D i The calculation formula is: ,in It is based on the current moment TA Calculate the air interface propagation delay value.

6. The high-precision 5G-TSN time synchronization method according to claim 1, characterized in that: In the compensation factor periodic update step, the update period is a preset time T. The UE periodically repeats the dual-mechanism delay measurement and compensation factor initialization steps to update the dynamic compensation factor. .

7. The high-precision 5G-TSN time synchronization method according to claim 1, characterized in that: The sliding window anomaly detection and emergency calibration steps include initializing the sliding window size. W Collection of latency sample sets ,in i Calculate the mean for the current sample number. and standard deviation σ, Dynamic thresholds are generated based on the 3σ criterion. For each sample within the window d i If satisfied If it does, it is marked as an exception.

8. The high-precision 5G-TSN time synchronization method according to claim 7, characterized in that: Triggered when an anomaly is detected RTT Remeasurement to update dynamic compensation factor And before the remeasurement is completed, the mean of the three normal samples before the abnormality within the sliding window is used as the temporary delay compensation value.

9. The high-precision 5G-TSN time synchronization method according to claim 1, characterized in that: The compensation delay value D i The correction field written into the synchronization message is used for downstream clock synchronization.

10. The high-precision 5G-TSN time synchronization method according to claim 1, characterized in that: The method is applied to 5G systems as a logical TSN bridge, and synchronization with the TSN master clock is achieved through NW-TT and DS-TT.

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