Synchronization method and device

Abstract

The embodiment of the present application provides a synchronization method and device, the method comprising: performing clock synchronization according to first clock information or second clock information. By determining to perform clock synchronization according to the first clock information or the second clock information, it is possible to effectively determine the implementation method of clock synchronization of the terminal device when the system information and the dedicated information exist at the same time, so as to ensure the clock synchronization between the network device and the terminal device.

Description

[0001] This application is a divisional application of the original Chinese invention patent application with the invention name of “Synchronization Method and Device”. The application number of the original application is 202080093475.3, and the application date of the original application is March 2, 2020. Technical Field

[0002] The present application relates to communication technology, and in particular to a synchronization method and device. Background Art

[0003] Time sensitive network (TSN) can ensure reliable deterministic transmission through time synchronization and real-time data scheduling. Therefore, in TSN, clock synchronization between terminal devices and network devices is particularly important.

[0004] At present, in the existing technology, the terminal device can receive system information and dedicated information from the network device to determine the clock information based on the system information and dedicated information, thereby realizing clock synchronization. The gNB (5G Node B) local oscillator may cause clock drift, and the different ways of sending system information and dedicated information will cause a certain delay. The clock drift and transmission delay will cause the network device to send different clock information to the terminal device through the system information and dedicated information.

[0005] When system information and dedicated information exist at the same time, which clock information should the terminal device use for clock synchronization? There is currently no effective solution, which makes it impossible to ensure clock synchronization between network devices and terminal devices. Summary of the invention

[0006] The embodiments of the present application provide a synchronization method and apparatus to avoid the problem of being unable to ensure clock synchronization between a network device and a terminal device.

[0007] In a first aspect, an embodiment of the present application provides a synchronization method, including:

[0008] Clock synchronization is performed according to the first clock information or the second clock information.

[0009] In a second aspect, an embodiment of the present application provides a synchronization device, including:

[0010] The synchronization module is used to perform clock synchronization according to the first clock information or the second clock information.

[0011] In a third aspect, an embodiment of the present application provides a terminal device, including: a transceiver, a processor, and a memory;

[0012] The memory stores computer-executable instructions;

[0013] The processor executes the computer-executable instructions stored in the memory, so that the processor performs the method in the above-mentioned first aspect or its various implementations.

[0014] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the method as described in the first aspect or its various implementation methods.

[0015] The embodiment of the present application provides a synchronization method and device, the method comprising: performing clock synchronization according to first clock information or second clock information. By determining to perform clock synchronization according to the first clock information or the second clock information, it is possible to effectively determine the implementation method of clock synchronization of the terminal device when the system information and the dedicated information exist at the same time, so as to ensure the clock synchronization between the network device and the terminal device. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of a communication scenario provided in an embodiment of the present application;

[0017] Figure 2 A schematic diagram of implementing the 5G network provided in the embodiment of the present application as a TSN bridge;

[0018] Figure 3 A schematic diagram of the timing relationship of clock synchronization between a terminal device and a network device provided in an embodiment of the present application;

[0019] Figure 4 The process of the synchronization method provided in the embodiment of the present application Figure 1 ;

[0020] Figure 5 A schematic diagram of a non-switching scenario provided in an embodiment of the present application;

[0021] Figure 6 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 1 ;

[0022] Figure 7 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 2 ;

[0023] Figure 8 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 3 ;

[0024] Fig. 9 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 4 ;

[0025] Fig.10Schematic diagram of determining clock information provided in an embodiment of the present application Figure 5 ;

[0026] Fig.11 A schematic diagram of a non-switching scenario provided in an embodiment of the present application;

[0027] Fig.12 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 6 ;

[0028] Fig.13 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 7 ;

[0029] Fig.14 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 8 ;

[0030] Fig.15 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 9 ;

[0031] Fig.16 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 10 ;

[0032] Fig.17 A schematic diagram of the structure of a synchronization device provided in an embodiment of the present application;

[0033] Fig.18 A schematic diagram of the structure of a terminal device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] To facilitate understanding, the concepts involved in this application are first explained.

[0035] Terminal equipment: It can be a device that includes wireless transceiver functions and can cooperate with network equipment to provide communication services to users. Specifically, terminal equipment can refer to user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication equipment, user agent or user device. For example, the terminal equipment can be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in a future 5G network or a network after 5G, etc.

[0036] Network equipment: A network equipment may be a device used to communicate with a terminal device, for example, it may be a base transceiver station (BTS) in a global system for mobile communication (GSM) or a code division multiple access (CDMA) communication system, or a base station (NodeB, NB) in a wideband code division multiple access (WCDMA) system, or an evolutionary NodeB (eNB or eNodeB) in an LTE system, or the network equipment may be a relay station, an access point, an in-vehicle device, a wearable device, a network-side device in a future 5G network or a network after 5G, or a network device in a future evolved public land mobile network (PLMN) network, etc.

[0037] Time-Sensitive Network: As a set of protocol clusters located at the data link layer, Time-Sensitive Network (TSN) mainly includes IEEE 802.1AS, IEEE 802.1Qbv, IEEE 802.1Qci, IEEE802.1Qcc, IEEE802.1Qch and other protocols, which changes the uncertainty of Ethernet from the underlying architecture and transforms it into a deterministic network. TSN provides common standards for managing the time nodes and process sequence of information interaction according to the time sensitivity of different task data. TSN has advantages in bandwidth, security and interoperability, and can well meet the requirements of industrial sites for real-time data. The priority application mechanism is an important working mechanism of TSN. By giving priority to the processing of key data packets during transmission, the rapid transmission of such data is guaranteed.

[0038] The network devices involved in the embodiments of the present application may also be referred to as Radio Access Network (RAN) devices. RAN devices are connected to terminal devices to receive data from terminal devices and send them to core network devices. RAN devices correspond to different devices in different communication systems, for example, base stations and base station controllers in 2G systems, base stations and radio network controllers (Radio Network Controller, RNC) in 3G systems, Evolutionary Node B (eNB) in 4G systems, and 5G systems, such as access network devices in NR (e.g., gNB, Central Unit (CU), Distribute Unit (DU)).

[0039] In addition, it should be understood that in the description of this application, words such as "first" and "second" are only used for the purpose of distinguishing the description, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying an order, nor can they be understood as indicating or implying an association relationship between similar nouns.

[0040] Next, combine Figure 1 , the scenarios to which the communication method in this application is applicable are described.

[0041] Figure 1 A schematic diagram of a communication scenario provided in an embodiment of the present application. Figure 1 , including a network device 101 and a terminal device 102, and wireless communication can be performed between the network device 101 and the terminal device 102.

[0042] The network including the network device 101 and the terminal device 102 may also be referred to as a non-terrestrial communication network (NTN), wherein NTN refers to a communication network between a terminal device and a satellite (also referred to as a network device).

[0043] It can be understood that the technical solution of the embodiment of the present application can be applied to the new radio (NR) communication technology, NR refers to the new generation of wireless access network technology, which can be applied to the future evolution network, such as the future fifth generation mobile communication (5G) system. The solution in the embodiment of the present application can also be applied to other wireless communication networks such as Wireless Fidelity (WIFI) and Long Term Evolution (LTE), and the corresponding names can also be replaced by the names of corresponding functions in other wireless communication networks.

[0044] The network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. A person of ordinary skill in the art can appreciate that with the evolution of the network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0045] Based on the communication scenarios described above, the technical background involved in this application is further introduced in detail below:

[0046] In the 5G industrial internet of things (IIoT), it is necessary to support the propagation of services such as industrial automation (factory automation), transmission automation (transport industry), and smart power (electrical power distribution) in the 5G system.

[0047] The services introduced above have strict requirements on latency and reliability of transmission, so the concept of TSN or time sensitive communication (TSC) is introduced in IIoT. TSN can ensure reliable deterministic transmission through time synchronization and real-time data scheduling.

[0048] In a TSN network, the 5G network can act as a TSN bridge to provide services for the TSN network and services. For example, the implementation of the 5G network as a TSN bridge can be as follows: Figure 2 As shown, Figure 2 A schematic diagram of the implementation of the 5G network provided in the embodiment of the present application as a TSN bridge.

[0049] Reference Figure 2 , the 5G network can provide services as a TSN bridge.

[0050] In order to use the 5G network as a TSN bridge, the NR system needs to provide lower latency guarantees and higher clock synchronization accuracy so that when industrial automation services are transmitted in the 5G network, the operation and connection of each point of mechanical operation are accurate and meet the clock requirements.

[0051] The following is an introduction to TSN clock synchronization accuracy:

[0052] Based on the requirements of TSN service transmission, when TSN services are transmitted in 5G, the terminal devices and network devices that execute TSN services need to meet the clock synchronization accuracy requirement of 1 microsecond (us). Specifically, whether the clock synchronization accuracy requirement of 1us can be achieved depends on the clock synchronization accuracy (accuracy) notified by the network device and the clock synchronization accuracy error (delta) of the terminal device. Figure 3 Introduce the timing relationship of clock synchronization between terminal devices and network devices. Figure 3 A schematic diagram of the timing relationship of clock synchronization between a terminal device and a network device provided in an embodiment of the present application.

[0053] like Figure 3 As shown in the figure, there are some deviations in the clock synchronization between the network device clock and the terminal device clock. The deviations in the clock synchronization are as follows: Figure 3 As shown in the area indicated by the two arrows in , it depends on the clock synchronization accuracy notified by the network device and the clock synchronization accuracy error of the terminal device.

[0054] In a possible implementation, the clock synchronization information and clock synchronization accuracy information notified by the network device can be included in the parameter (TimeReferenceInfo IE); the clock synchronization accuracy error of the terminal device can be determined by the physical layer, and its clock synchronization accuracy error is related to many factors, such as propagation loss, device limitations, etc.

[0055] Based on the clock synchronization accuracy error introduced above, according to the liaison statement (LS) from the physical layer, in some scenarios, such as when the distance between the UE and the base station exceeds 200m, it is necessary to compensate for the propagation delay between the terminal device and the network device so that the clock synchronization accuracy error of the physical layer can be controlled within the required range, so as to ultimately ensure that the TSN service can meet the 1us clock synchronization accuracy requirement when propagating within 5G.

[0056] LS is described in detail in the following quotation from the physical layer:

[0057] “RAN1 has performed analysis on the achievable timesynchronization accuracy over Uu interface.A timing synchronization errorbetween a gNB and a UE no worse than 540ns is achievable based on the RAN1agreed evaluation assumptions for Rel-15 NR with 15kHz SCS.It is RAN1′sconclusion,that the synchronization accuracy is improved when using higherSCS.For small service areas with dense small cell deployments, no propagation delay compensation by the UE will be required. Propagation delay compensation will need to be applied by the TSN UE for larger service areas and sparser cell deployments (e.g., for inter-site distance > 200m, the timing synchronization accuracy from gNB to UE without propagation delay compensation may be less than 1us)” small service areas with dense small cell deployments a propagationdelay

[0058] compensation by the UE would not be required.The propagation delay

[0059] compensation needs to be applied by the TSN UEs for larger serviceareas with more sparse cell deployments(egfor inter-site distances>200m thegNB-to-UE timing synchronization accuracy without propagation delaycompensation may be worse than 1us)).”

[0060] In general, based on the conclusions of the physical layer contact letter and the radio access network (RAN) 2, it is necessary to consider the method of implementing propagation delay compensation in the scenario where the distance between the terminal device and the network device is greater than 200 meters (m) to achieve clock synchronization.

[0061] In a possible method for implementing propagation delay compensation, for example, time alignment (TA) can be used for propagation delay compensation, wherein TA means that the terminal device sends a data packet in advance according to the corresponding instruction to achieve propagation delay compensation between the terminal device and the network device.

[0062] According to the current conclusions, the propagation delay compensation between the terminal device and the network device can be performed by the terminal device. For example, the terminal device determines the compensation value based on the TA value and implements the propagation delay compensation based on the compensation value. Under normal circumstances, the compensation value can be 0.5TA or 0.5Nta.

[0063] Based on the above embodiments, the clock synchronization of TSN is introduced below:

[0064] In R16, only the scenario where the network device is used as the master TSN clock node is supported. Accordingly, the TSN clock information is notified to the terminal device by the network device, and the terminal device synchronizes with the network device based on the received clock information.

[0065] In R17, the scenario of terminal devices acting as master TSN clock nodes is further supported. When the terminal devices act as master TSN clock nodes, the basic synchronization method between the terminal devices and network devices may still be that the terminal devices and network devices perform 5G system synchronization, and the corresponding network devices send clock information.

[0066] Based on this assumption and the requirements for TSN service transmission introduced above, when TSN services are transmitted within 5G, terminal devices and network devices need to be clock synchronized. Accordingly, the network device provides reference clock information to the terminal device so that the terminal device and the network device can achieve clock synchronization.

[0067] Furthermore, in order to meet the clock synchronization accuracy requirement of 1us, the network device may send clock information to the terminal device. The clock information may include TSN clock synchronization information and more accurate clock synchronization accuracy information, wherein the clock information may be included in the parameter TimeReferenceInfo IE.

[0068] In a possible implementation, the network device may send the clock information to the terminal device by broadcasting, for example, the network device sends system information, such as SIB9, to the terminal device by broadcasting, wherein the system information includes the clock information;

[0069] Alternatively, the network device may also send the clock information to the terminal device in a unicast manner, for example, the network device sends dedicated information to the terminal device in a unicast manner, such as dedicated RRC, DLinformationtransfer, wherein the dedicated information includes the clock information;

[0070] The granularity of the clock synchronization accuracy is 10 nanoseconds (ns).

[0071] To summarize, currently network equipment can send clock information to terminal equipment through system information and dedicated information so that the terminal equipment performs clock synchronization according to the clock information. However, due to reasons such as the gNB local oscillator, clock drift may occur, as well as the delay caused by the different ways of sending different information (system information and dedicated information), and other reasons, the clock information sent by the network equipment to the terminal equipment through system information and dedicated information is different. In this case, it is still unknown which clock information the terminal equipment should use for clock synchronization.

[0072] Based on the above-mentioned problems, the present application proposes the following technical concept: clock synchronization is performed according to the first clock information or the second clock information provided by the network device, that is, which clock information will be used for synchronization is determined.

[0073] The synchronization method provided by the present application is described in detail below in conjunction with specific embodiments. Figure 4 To explain, Figure 4 The process of the synchronization method provided in the embodiment of the present application Figure 1 ,like Figure 4 As shown, the method includes:

[0074] S401. Perform clock synchronization according to first clock information or second clock information.

[0075] In this embodiment, the first clock information and the second clock information are information used for clock synchronization of the terminal device, wherein the first clock information is determined according to the system information, and the second clock information is determined according to the dedicated information.

[0076] Taking the first clock information as an example, in a possible implementation method, the first clock information may, for example, instruct the terminal device to perform propagation delay compensation; or, the first clock information may, for example, instruct the terminal device not to perform propagation delay compensation; or, the first clock information may, for example, indicate the conditions for the terminal device to perform propagation delay compensation; or, the first clock information may indicate whether the network device has performed propagation delay compensation; or, the first clock information may indicate whether the master clock node has performed propagation delay compensation; or, the first clock information may, for example, not indicate propagation delay compensation information.

[0077] Taking the first clock information as an example, in a possible implementation, the first clock information may indicate, for example, a reference SFN of the terminal device, the time corresponding to the reference SFN (such as the hour, minute, and second, etc.), the reference clock type, the inaccuracy, and so on.

[0078] The implementation method of the second clock information is similar to that of the first clock information. This embodiment does not limit the specific implementation method of the first clock information and the second clock information. All information used by the terminal device for clock synchronization can be considered as the first clock information or the second clock information in this embodiment, and its implementation method can be expanded according to actual needs.

[0079] The following is an example of implementing clock synchronization of a terminal device. Assuming that it is currently determined to perform clock synchronization according to first clock information, the terminal device is synchronized according to the first clock information.

[0080] Alternatively, assuming that it is currently determined to perform clock synchronization based on the first clock information, and the first clock information indicates a first condition for the terminal device to perform propagation delay compensation, then when the first condition is met, the terminal device performs propagation delay compensation to achieve clock synchronization between the terminal device and the network device.

[0081] In another possible implementation, it can also be determined that clock synchronization is performed based on the second clock information. This embodiment does not limit which clock information is used for clock synchronization, as long as it can be determined that clock synchronization is performed based on one of the first clock information or the second clock information.

[0082] Based on the above introduction, it can be determined that when system information and dedicated information exist at the same time, which clock information should the terminal device use for clock synchronization? There is currently no effective solution.

[0083] In an embodiment of the present application, by determining whether to perform clock synchronization based on the first clock information or the second clock information, it is possible to effectively determine the implementation method of clock synchronization of the terminal device when the system information and the dedicated information exist at the same time, so as to ensure the clock synchronization between the network device and the terminal device.

[0084] Based on the above introduction, the synchronization method provided in the embodiment of the present application may further include two application scenarios, namely a non-switching scenario and a switching scenario, wherein the non-switching scenario refers to a connection established between the terminal device and the first network device;

[0085] The switching scenario refers to the switching of the network device to which the terminal device is connected from the first network device to the second network device. In a possible implementation, during the movement of the terminal device, it is necessary to switch from a small cell base station (usually referred to as the source base station, that is, the first network device in this implementation) to another small cell base station (usually referred to as the target base station, that is, the second network device in this embodiment). This switching process is often referred to as terminal device switching; or, switching from one cell under a base station to another cell, that is, intra-base station switching, is also a switching scenario in this embodiment.

[0086] The following introduces the implementation methods of these two application scenarios respectively.

[0087] First combine Figure 5 Introduce the non-switching scenario. Figure 5 A schematic diagram of a non-switching scenario provided in an embodiment of the present application, such as Figure 5 As shown:

[0088] The terminal device can obtain the first clock information and the second clock information.

[0089] In a possible implementation manner, the terminal device may receive first system information from the first network device, and obtain first clock information according to the first system information.

[0090] See also Figure 5 The terminal device can receive the first system information indicated by the first network device through broadcast, and the first system information can be, for example, a system information block (SIB) 9, wherein the broadcasted first system information can be applicable to all terminal devices under the coverage of the first network device.

[0091] Furthermore, the terminal device may also receive first dedicated information from the first network device, and obtain second clock information according to the first dedicated information.

[0092] See also Figure 5 The terminal device can receive the first dedicated information indicated by the first network device through unicast, and the first dedicated information can be, for example, a dedicated radio resource control (RRC) message, such as DLinformationtransfer, wherein the second clock information indicated by the first network device to each terminal device under the coverage through the second dedicated information can be different or the same.

[0093] based on Figure 5 In the non-switching scenario described above, the terminal device obtains the first clock information through the first system information and obtains the second clock information through the first dedicated information. That is to say, the terminal device obtains the clock information through both the system information and the dedicated information. Based on this, the following is combined with Figures 6 to 10 Several possible implementation methods of clock synchronization according to the first clock information or the second clock information in a non-switching scenario are introduced. Figure 6 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 1 , Figure 7 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 2 , Figure 8 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 3 , Fig. 9 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 4 , Fig.10 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 5 .

[0094] In one possible implementation, see Figure 6 , the terminal device is always synchronized according to the second clock information.

[0095] That is, no matter what the first clock information and the second clock information are, the second clock information included in the first dedicated information is always used for clock synchronization.

[0096] In another possible implementation, see Figure 7 , the first clock information and the second clock information are the same, and the terminal device can perform clock synchronization according to either the first clock information or the second clock information.

[0097] In another possible implementation, see Figure 8, the first clock information and the second clock information are the same, and the terminal device performs clock synchronization according to the second clock information.

[0098] In yet another possible implementation, see Fig. 9 The first clock information is different from the second clock information, and the terminal device performs clock synchronization according to the second clock information.

[0099] In yet another possible implementation, see Fig.10 , within the first time period, clock synchronization is performed according to the second clock information. Further, when the first time period times out, clock synchronization is performed according to the first clock information.

[0100] In this embodiment, there are multiple ways to implement the first duration. Various possible ways to implement the first duration are introduced below:

[0101] The first time length may be, for example, the valid time of the second clock information, or the first time length may be before the first timer times out.

[0102] The first duration may be indicated by the first system information; or the first duration may be indicated by the first information; or the first duration may be indicated by the first dedicated information; or the first duration may also be predefined.

[0103] The first information introduced above may be, for example, RRC, broadcast, media access control layer (Media Access Control, MAC) control element (Control Element, CE), downlink control information (downlink control information, DCI)

[0104] In this embodiment, the first clock information and / or the second clock information may further include a reference system frame number (SFN), or indicate a reference SFN; or, the first clock information and / or the second clock information may further include time (such as the hour, minute, and second, etc.).

[0105] In this embodiment, the starting time point of the first duration may be the position of the reference SFN. Specifically, the position of the reference SFN may be any one of the boundary of the reference SFN, the starting point of the reference SFN, the ending point of the reference SFN, and the first moment after the ending point of the reference SFN (such as the first time slot, the first SFN, the first symbol); or

[0106] The starting time point corresponding to the first duration is the position of the reference SFN plus the first delay; or

[0107] The starting time point corresponding to the first duration is when the switching is completed; or

[0108] The starting time point corresponding to the first duration is the time when the switching is completed minus the first delay; or

[0109] The starting time point corresponding to the first duration is the time when the switching is completed minus the second delay, wherein the second delay can be the first delay+A, A can be the switching time, or A can also be the random access time.

[0110] In this embodiment, the first time point corresponding to the first dedicated information may also be determined according to the first dedicated information, wherein the first time point corresponding to the dedicated information includes at least one of the following:

[0111] The time point when the first dedicated information including the second clock information is received, the time point when the first dedicated information including the second clock information is decoded, and the time point when the first dedicated information configuration is enabled.

[0112] The starting time point corresponding to the first duration may also be the first time point; or

[0113] The starting time point corresponding to the first duration may also be the first time point minus the first delay.

[0114] The first delay described above may be one of the following: an interface delay, a time period corresponding to the interface delay, or a sum of the interface delay and the transmission delay.

[0115] For example, the interface delay may be the interface delay (the delay of Xn interface, or S1 interface delay) for sending clock information from the second network device to the first network device in a handover (HO) scenario.

[0116] In another possible implementation, if the terminal device receives new second clock information within the first time period, for example, it can be received through new first dedicated information (such as dedicated RRC), the terminal device can perform clock synchronization according to the new second clock information.

[0117] In a possible implementation, after receiving the new second clock information, clock synchronization may be performed immediately according to the new second clock information; or,

[0118] After receiving the first duration of the new second clock information, clock synchronization may be performed according to the new second clock information.

[0119] After introducing the implementation of non-switching scenarios, Fig.11 Introduce the switching scene. Fig.11A schematic diagram of a non-switching scenario provided in an embodiment of the present application, such as Fig.11 As shown:

[0120] Assuming that the terminal device establishes a connection with the first network device, user data will be exchanged between the terminal device and the first network device, and assuming that the current terminal device needs to switch from the first network device to the second network device, then

[0121] S1. The first network device sends a handover request to the second network device;

[0122] S2. The second network device performs admission control and uplink resource coordination according to the received handover request to prepare to establish a connection with the terminal device;

[0123] S3. The second network device sends a handover request (acknowledgement, ACK) to the first network device, wherein the handover request ACK carries the clock information of the second network device;

[0124] S4. The first network device sends a handover command (HO command) to the terminal device according to the received handover request ACK, wherein the handover command includes the clock information of the second network device, and the HO command in this embodiment is dedicated information, so the handover command specifically includes the second clock information;

[0125] In this embodiment, the terminal device may store the second clock information;

[0126] S5, the terminal device, the first network device and the second network device perform a switching process;

[0127] S6. The terminal device synchronizes the clock with the second network device.

[0128] And reference Fig.11 It can be determined that, in another possible implementation, the terminal device may also receive first clock information from the second network device, which may be sent by the second network device through second system information (such as SIB9), for example.

[0129] In the switching scenario of this embodiment, when the terminal device performs clock synchronization with the second network device, the terminal device can directly perform clock synchronization according to the received second clock information without receiving the first clock information; or, the terminal device can also receive the first clock information and the second clock information, and then perform clock synchronization according to the first clock information or the second clock information. Figure 12-Figure 15 Various possible implementation methods in the switching scenario are introduced respectively. Fig.12Schematic diagram of determining clock information provided in an embodiment of the present application Figure 6 , Fig.13 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 7 , Fig.14 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 8 , Fig.15 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 9 , Fig.16 Schematic diagram of determining clock information provided in an embodiment of the present application Figure 10 .

[0130] First, we introduce clock synchronization directly based on the received second clock information:

[0131] In one possible implementation, see Fig.12 The terminal device can receive the second dedicated information, obtain the second clock information according to the second dedicated information, and directly perform clock synchronization according to the second clock information. Alternatively, the terminal device can obtain the second clock information for a second period of time and then use the second clock information to synchronize with the second network device; that is, there is no need to obtain the first clock information at this time.

[0132] In a possible implementation of this embodiment, see the above Fig.11 In the scenario introduced, the second dedicated information may be a handover command (HO command), and the second clock information may be carried in a handover request ACK or other interface message, that is, the second clock information may be obtained through the second network device; or, the second dedicated information may also be any information used to send the second clock information. This embodiment does not limit the implementation method of the second dedicated information.

[0133] Next, it is introduced that the first clock information and the second clock information are received, and then clock synchronization is performed according to the first clock information or the second clock information.

[0134] In another possible implementation, in addition to obtaining the second clock information, the terminal device also obtains the first clock information based on the second system information of the second network device, where the second system information may be SIB9, for example, that is, the first clock information and the second clock information currently exist at the same time.

[0135] It is understandable that the first clock information and the second clock information may be the same or different. Based on this, there may be multiple implementation methods:

[0136] See also Fig.13 , the first clock information and the second clock information are different, and clock synchronization can be performed according to the first clock information;

[0137] It should be noted here that in the HO process, the second dedicated information is forwarded through the XN / S1 interface. There is a delay X in the forwarding process of the XN / S1 interface. The second clock information may change during this delay X. Therefore, when the first clock information and the second clock information are different, synchronization cannot be performed through the second clock information notified by the second dedicated information. Instead, clock synchronization is performed according to the first clock information to ensure the accuracy of clock synchronization.

[0138] In another possible implementation, if the first clock information and the second clock information are different, the second network device may further send third dedicated information to the terminal device. The third dedicated information may be, for example, a dedicated RRC message, such as DLinformationtransfer. At this time, the terminal device can perform clock synchronization according to the clock information in the third dedicated information. Moreover, before receiving the third dedicated information, the terminal device can still obtain the clock information by broadcast or switching command, and synchronize according to the clock information.

[0139] The third dedicated information is sent directly from the second network device to the first network device without being forwarded via the XN interface, thus avoiding a delay of X and ensuring the accuracy of clock synchronization.

[0140] Alternatively, see Fig.14 , the first clock information and the second clock information are the same, and clock synchronization can be performed according to either the first clock information or the second clock information; or

[0141] See also Fig.15 , the first clock information and the second clock information are the same, and clock synchronization can be performed according to the second clock information.

[0142] In this embodiment, the second system information received by the terminal device from the second network device may be received in the following situations:

[0143] received during a handover of a terminal device; or

[0144] received after the handover of the terminal equipment is completed; or

[0145] Received after the random access process of the terminal device is successful.

[0146] The handover completion means that the network device handover is completed, the random access process success means that the terminal device and the second network device complete the random access process, and the handover process may include at least one of the following:

[0147] The terminal device obtains the system target SFN information during the switching process, the terminal device obtains or reads the SFN information of the second network device during the switching process (then, uses the SFN of the second network device as a reference), and the terminal device uses the system frame number SFN of the first network device as a reference.

[0148] In another possible implementation, in a switching scenario, the first duration may also be used to determine which clock information to use for clock synchronization.

[0149] See also Fig.16 , within the first time period, clock synchronization is performed according to the second clock information. Further, when the first time period times out, clock synchronization is performed according to the first clock information.

[0150] In this embodiment, there are multiple ways to implement the first duration. Various possible ways to implement the first duration are introduced below:

[0151] The first time length may be, for example, the valid time of the second clock information, or the first time length may be before the first timer times out.

[0152] The first duration may be indicated by the second system information; or the first duration may be indicated by the first information; or the first duration may be indicated by the second dedicated information; or the first duration may also be predefined.

[0153] The first information introduced above can be, for example, RRC, broadcast, MAC CE, DCI

[0154] In this embodiment, the first clock information and / or the second clock information may further include a reference SFN, or indicate a reference SFN; or, the first clock information and / or the second clock information may further include time (such as the hour, minute, and second, etc.).

[0155] In this embodiment, the starting time point of the first duration may be the position of the reference SFN. Specifically, the position of the reference SFN may be any one of the boundary of the reference SFN, the starting point of the reference SFN, the ending point of the reference SFN, and the first moment after the ending point of the reference SFN (such as the first time slot, the first SFN, the first symbol); or

[0156] The starting time point corresponding to the first duration is the position of the reference SFN plus the first delay; or

[0157] The starting time point corresponding to the first duration is when the switching is completed; or

[0158] The starting time point corresponding to the first duration is the time when the switching is completed minus the first delay; or

[0159] The starting time point corresponding to the first duration is the time when the switching is completed minus the second delay, wherein the second delay can be the first delay+A, A can be the switching time, or A can also be the random access time.

[0160] In this embodiment, the first time point corresponding to the second dedicated information may also be determined according to the second dedicated information, wherein the first time point corresponding to the dedicated information includes at least one of the following:

[0161] The time point of receiving the second dedicated information including the second clock information, the time point of decoding the second dedicated information including the second clock information, and the time point of enabling the second dedicated information configuration.

[0162] The starting time point corresponding to the first duration may also be the first time point; or

[0163] The starting time point corresponding to the first duration may also be the first time point minus the first delay.

[0164] The first delay described above may be one of the following: an interface delay, a time period corresponding to the interface delay, or a sum of the interface delay and the transmission delay.

[0165] For example, the receiving delay may be the interface delay (the delay of Xn interface, or S1 interface delay) for sending clock information from the second network device to the first network device in a handover (HO) scenario.

[0166] In another possible implementation, if the terminal device receives new second clock information within the first time period, for example, it can be received through new first dedicated information (such as dedicated RRC), the terminal device can perform clock synchronization according to the new second clock information.

[0167] In a possible implementation, after receiving the new second clock information, clock synchronization may be performed immediately according to the new second clock information; or,

[0168] After receiving the first duration of the new second clock information, clock synchronization may be performed according to the new second clock information.

[0169] It is understandable that the above-described implementation method of determining the clock information based on the first duration is similar in switching scenarios and non-switching scenarios. The difference is that the first clock information and the second clock information may be obtained differently in different scenarios.

[0170] To sum up, the synchronization method provided in this embodiment provides a method for determining the clock information used by the terminal device when performing clock synchronization, clarifies the behavior of the terminal device, thereby ensuring the clock synchronization between the terminal device and the network device, and ensuring the synchronization requirements of the terminal device and the transmission requirements of the TSC service.

[0171] Fig.17 This is a schematic diagram of the structure of the synchronization device provided in the embodiment of the present application. Fig.17 The synchronization device 170 may include a synchronization module 1701, an acquisition module 1702 and a determination module 1703, wherein:

[0172] The synchronization module 1701 is used to perform clock synchronization according to the first clock information or the second clock information.

[0173] In a possible implementation manner, the first clock information and the second clock information are information used by the synchronization device to perform clock synchronization.

[0174] In a possible implementation manner, the synchronization device is connected to the first network equipment.

[0175] In a possible implementation, the device further includes: an acquisition module 1702;

[0176] The acquisition module 1702 is used to acquire the first clock information and the second clock information.

[0177] In a possible implementation, the acquisition module 1702 is specifically used to:

[0178] receiving first system information from the first network device, and acquiring first clock information according to the first system information; and

[0179] Receive first dedicated information from the first network device, and acquire second clock information according to the first dedicated information.

[0180] In a possible implementation, the first clock information and the second clock information are the same, and the synchronization module 1701 is specifically configured to:

[0181] Clock synchronization is performed according to any one of the first clock information and the second clock information.

[0182] In a possible implementation, the first clock information and the second clock information are the same, and the synchronization module 1701 is specifically configured to:

[0183] Clock synchronization is performed according to the second clock information.

[0184] In a possible implementation manner, the first clock information and the second clock information are different, and the synchronization module 1701 is specifically configured to:

[0185] Clock synchronization is performed according to the second clock information.

[0186] In a possible implementation manner, the synchronization device is switched from the first network device to the second network device.

[0187] In a possible implementation, the obtaining module 1702 is further configured to:

[0188] Receive second dedicated information, and acquire the second clock information according to the second dedicated information.

[0189] In a possible implementation manner, the second dedicated information is a switching command.

[0190] In a possible implementation manner, the second clock information is acquired through the second network device.

[0191] In a possible implementation manner, the second clock information is carried in switching request confirmation information ACK, wherein the switching request ACK is sent by the second network device to the first network device.

[0192] In a possible implementation, the synchronization module 1701 is specifically used for:

[0193] Clock synchronization is performed according to the second clock information.

[0194] In a possible implementation, the obtaining module 1702 is further configured to:

[0195] The first clock information is acquired according to the second system information of the second network device.

[0196] In a possible implementation manner, the second system information is received during a switching process of the synchronization device; or

[0197] The second system information is received after the switching of the synchronization device is completed; or

[0198] The second system information is received after a random access procedure of the synchronization device succeeds.

[0199] In a possible implementation manner, the switching process of the synchronization device includes at least one of the following:

[0200] The synchronization device obtains the system target SFN information during the switching process, the switching process of the synchronization device includes the synchronization device obtaining or reading the SFN information of the second network device during the switching process, and the switching process of the synchronization device includes the synchronization device using the system frame number SFN of the first network device as a reference.

[0201] In a possible implementation manner, the first clock information and the second clock information are different, and the synchronization module 1701 is specifically configured to:

[0202] Clock synchronization is performed according to the first clock information.

[0203] In a possible implementation, the first clock information and the second clock information are the same, and the synchronization module 1701 is specifically configured to:

[0204] Perform clock synchronization according to any one of the first clock information and the second clock information; or,

[0205] Clock synchronization is performed according to the second clock information.

[0206] In a possible implementation manner, performing clock synchronization according to the first clock information or the second clock information includes at least one of the following:

[0207] Performing clock synchronization according to the second clock information within a first time period;

[0208] When the first duration times out, clock synchronization is performed according to the first clock information.

[0209] In a possible implementation, the obtaining module 1702 is further configured to:

[0210] Within the first time period, the synchronization device receives new second clock information.

[0211] In a possible implementation, the synchronization module 1701 is specifically used for:

[0212] Clock synchronization is performed according to the new second clock information.

[0213] In a possible implementation, the synchronization module 1701 is specifically used for:

[0214] After receiving the new second clock information, performing clock synchronization according to the new second clock information; or,

[0215] After the first time period, clock synchronization is performed according to the new second clock information.

[0216] In a possible implementation manner, the first duration is indicated by system information; or

[0217] The first duration is indicated by the first information; or

[0218] The first duration is indicated by dedicated information.

[0219] In a possible implementation manner, the first clock information and / or the second clock information further includes a reference SFN; or

[0220] The first clock information and / or the second clock information further indicates a reference SFN.

[0221] In a possible implementation manner, the starting time point corresponding to the first duration is the position of the reference SFN.

[0222] In a possible implementation manner, the starting time point corresponding to the first duration is the position of the reference SFN plus a first delay.

[0223] In a possible implementation, the device further includes: a determination module 1703;

[0224] The determination module 1703 is used to determine a first time point corresponding to the dedicated information according to the dedicated information.

[0225] In a possible implementation manner, the first time point corresponding to the dedicated information includes at least one of the following:

[0226] The time point of receiving the dedicated information including the clock information, the time point of decoding the dedicated information including the clock information, and the time point of enabling the dedicated information configuration.

[0227] In a possible implementation manner, the starting time point corresponding to the first duration is the first time point; or

[0228] The starting time point corresponding to the first duration is the first time point minus the first delay.

[0229] In a possible implementation, the starting time point corresponding to the first duration is when the switching is completed.

[0230] In a possible implementation, the starting time point corresponding to the first duration is the time when the switching is completed minus the first delay.

[0231] In a possible implementation manner, the first delay is one of the following: an interface delay, a time period corresponding to the interface delay, and a sum of the interface delay and the transmission delay.

[0232] The synchronization device provided in the embodiment of the present application can execute the technical solution shown in the above method embodiment, and its implementation principle and beneficial effects are similar, which will not be repeated here.

[0233] Fig.18 This is a schematic diagram of the structure of the terminal device provided in the embodiment of the present application. Fig.18 The terminal device 20 may include: a transceiver 21, a memory 23, and a processor 22. The transceiver 21 may include: a transmitter and / or a receiver. The transmitter may also be referred to as a transmitter, a transmitter, a transmission port, a transmission interface, or similar descriptions, and the receiver may also be referred to as a receiver, a receiver, a reception port, a reception interface, or similar descriptions. Exemplarily, the transceiver 21, the memory 23, and the processor 22 are interconnected via a bus 24.

[0234] The memory 23 is used to store program instructions;

[0235] The processor 22 is used to execute the program instructions stored in the memory, so as to enable the terminal device 20 to execute any of the synchronization methods shown above.

[0236] The receiver of the transceiver 21 can be used to perform the receiving function of the terminal device in the above synchronization method.

[0237] An embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the above-mentioned synchronization method.

[0238] The embodiment of the present application may also provide a computer program product, which may be executed by a processor. When the computer program product is executed, the synchronization method executed by any of the terminal devices shown above may be implemented.

[0239] The synchronization device, computer-readable storage medium and computer program product of the embodiments of the present application can execute the synchronization method executed by the above-mentioned terminal device. The specific implementation process and beneficial effects thereof are as mentioned above and will not be repeated here.

[0240] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0241] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0242] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0243] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned method embodiments are implemented; and the aforementioned storage medium includes: Read Only Memory (ROM), Random Access Memory (RAM), a magnetic disk or an optical disk, etc., various media that can store program codes.

[0244] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A synchronization method, characterized in that: Applied to terminal equipment, including: Acquire first clock information and second clock information; Performing clock synchronization according to the first clock information or the second clock information; The acquiring the first clock information and the second clock information includes: receiving first system information from a first network device, and acquiring first clock information according to the first system information; and receiving first dedicated information from the first network device, and acquiring second clock information according to the first dedicated information; The performing clock synchronization according to the first clock information or the second clock information includes: Performing clock synchronization according to the second clock information within a first time period; When the first duration times out, performing clock synchronization according to the first clock information; Among them, the first clock information and / or the second clock information indicates the reference system frame number SFN; the starting time point of the first duration is the position of the reference SFN, or the starting time point corresponding to the first duration is the position of the reference SFN plus a first delay.

2. The method according to claim 1, characterized in that: The first clock information and the second clock information are information used for clock synchronization of the terminal device.

3. A synchronization device, characterized in that: Applied to terminal equipment, including: An acquisition module, used to acquire first clock information and second clock information; A synchronization module, used for performing clock synchronization according to the first clock information or the second clock information; The acquisition module is specifically used for: receiving first system information from a first network device, and acquiring first clock information according to the first system information; and receiving first dedicated information from the first network device, and acquiring second clock information according to the first dedicated information; The synchronization module is specifically used for: Performing clock synchronization according to the second clock information within a first time period; When the first duration times out, performing clock synchronization according to the first clock information; Among them, the first clock information and / or the second clock information indicates the reference system frame number SFN; the starting time point of the first duration is the position of the reference SFN, or the starting time point corresponding to the first duration is the position of the reference SFN plus a first delay.

4. The device according to claim 3, characterized in that The first clock information and the second clock information are information used for clock synchronization of the terminal device.

5. A synchronization method, characterized in that: Applied to a first network device, comprising: Sending first system information to a terminal device, where the first system information is used to indicate first clock information to the terminal device; Sending first dedicated information to a terminal device, where the first dedicated information is used to indicate second clock information to the terminal device; Among them, the first clock information is used for the terminal device to perform clock synchronization after the first time duration expires, and the second clock information is used for the terminal device to perform clock synchronization within the first time duration; the first clock information and / or the second clock information indicates the reference system frame number SFN; the starting time point of the first time duration is the position of the reference SFN, or the starting time point corresponding to the first time duration is the position of the reference SFN plus a first delay.

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