CN110662284A

CN110662284A - Method and device for correcting time information

Info

Publication number: CN110662284A
Application number: CN201810688618.XA
Authority: CN
Inventors: 杨坤; 高峰; 于光炜; 汲桐
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-06-28
Filing date: 2018-06-28
Publication date: 2020-01-07
Anticipated expiration: 2038-06-28
Also published as: WO2020001367A1; CN110662284B

Abstract

The application provides a method and a device for correcting time information, wherein the method comprises the following steps: the base station may determine a time offset before and after clock updating, and send the indication information including the time offset to the terminal device, specifically, the base station may load the indication information including Δ T information in a reference signal, for example, take the time offset included in the indication information as an input parameter in a sequence generation or resource mapping process of the reference signal, so that the terminal device acquires the information about the time offset from the received reference signal; the terminal equipment corrects the time information according to the time deviation, and the method can reduce the timing error between a wireless frame timing system and a time system of an external clock and improve the accuracy of time synchronization of the terminal equipment and the base station.

Description

Method and device for correcting time information

Technical Field

The present application relates to the field of communications, and more particularly, to a method and apparatus for transmitting a time offset amount and correcting time information in the field of communications.

Background

Wireless communication technology has been widely used in a variety of scenarios. For example, motion control (motion control), discrete automation (discrete automation), distributed power system (electrical distribution), etc., which are new application scenarios that place new demands on the communication system. For example, low latency and high reliability communication (URLLC), high connection density (high connection density), time synchronization that meets the industrial bus standard IEC61508 of the International Electrotechnical Commission (IEC), and the like.

Taking the terminal device and the network device as examples, the time synchronization means that the time systems of the terminal device and the network device are kept synchronized. A time system is understood to be a time system operating according to an international standard, such as coordinated Universal Time (UTC), Global Navigation Satellite System (GNSS), etc., or according to a proprietary standard, such as a time system defined within a local area network. In different industrial application scenarios, the accuracy of time synchronization required by terminal devices is different, and for example, special application scenarios such as industrial bus and power grid fault detection require that the accuracy of time synchronization between a plurality of terminal devices reaches ± 1 us. Fifth generation (5G) mobile communication systems have required tighter time synchronization, requiring time offsets of ± 500 ns.

For both the base station and the terminal equipment, there are two different timing systems, respectively, a time system of the clock module and a wireless frame timing system of the communication module. Specifically, for example, the base station includes a clock module and a communication module, the clock module communicates with an external clock source, and acquires time information of a time system for correcting the clock module. The communication module can ensure the radio frame timing synchronization of the terminal equipment within the coverage of one base station based on a specific radio frame structure and a radio frame number. Due to the difference between the communication module and the clock module, a time deviation amount exists between a wireless frame timing system and a time system of the clock module, so that time deviation is generated in the time synchronization process of the terminal equipment and the base station, and high-precision time synchronization is influenced. Therefore, how to guarantee the accuracy of time synchronization between the terminal device and the base station is a problem that needs to be solved urgently in the industry.

Disclosure of Invention

The application provides a method and a device for correcting time information, which can reduce the timing error between a wireless frame timing system and a time system of an external clock and improve the accuracy of time synchronization between terminal equipment and a base station.

In a first aspect, a communication method is provided, including: determining the time deviation amount before and after the clock updating; and sending indication information, wherein the indication information comprises the information of the time deviation amount.

Specifically, a time deviation amount is determined, which is a time deviation amount between the times recorded under different timing systems at the occurrence time of a specific event, i.e. a deviation amount between a first time recorded based on a first time coordinate system and a second time recorded based on a second time coordinate system, wherein the specific event may refer to an unambiguous event occurring at the sending end device, such as the sending of a specific signal, the sending of a specific data packet, a specific frame timing trigger, etc.; the first time is the occurrence time of the specific event in a first time coordinate system, the second time is the occurrence time of the specific event in a second time coordinate system, and the first time coordinate system is different from the second time coordinate system.

Specifically, the first time coordinate system may be a coordinate system of a time system based on external clock timing, the second time coordinate system may be a coordinate system based on a wireless frame timing system, and the time deviation amount may be a timing deviation amount between a first time based on external clock timing and a second time based on wireless frame timing system timing.

According to the technical scheme, the base station sends the information of the time deviation delta T to the terminal equipment, and the terminal equipment corrects the time information according to the information of the delta T. The base station may send information of the time offset Δ T between the radio frame timing system and the time system of the external clock to the terminal device. And after receiving the information of the delta T, the terminal equipment corrects the time information according to the information of the delta T, adds or subtracts the time information and the time deviation amount, and takes the operation result as new time information. The time information of the terminal equipment can be updated in time, the validity of the time information is guaranteed, and the timing error caused by periodic updating of an external clock is reduced, so that the accuracy of time synchronization of the terminal equipment and the base station is improved.

With reference to the first aspect, in certain implementations of the first aspect, the indication information is carried in a reference signal.

With reference to the first aspect and the foregoing implementations, in some possible implementations, the sequence of reference signals is generated according to the amount of time deviation; or

And the sequence of the reference signal is mapped to time-frequency resources according to the time deviation value.

The method for sending the indication information by the reference signal can send the indication information to the terminal equipment by utilizing the unicast or multicast message of the base station, so that the mode for sending the indication information is more flexible; meanwhile, the time information of the terminal equipment can be corrected in time under the condition of not influencing the period of broadcasting and sending the time information in the cell, and the validity of the reference time is ensured, so that the time synchronization with the base station is realized.

With reference to the first aspect and the foregoing implementation manners, in some possible implementation manners, the indication information is carried in downlink control information DCI, a media access control element MAC CE, or radio resource control RRC signaling.

By the method for transmitting the indication information, the information of the time deviation amount can be transmitted to the terminal equipment by utilizing the fully existing DCI, MAC CE or RRC signaling; and meanwhile, the time information of the terminal equipment is updated in time, and the validity of the reference time is ensured, so that the time synchronization with the base station is realized.

With reference to the first aspect and the foregoing implementation manners, in some possible implementation manners, the sending the indication information includes:

and when the time deviation amount is greater than or equal to a preset first threshold, sending the indication information.

With reference to the first aspect and the foregoing implementation manners, in some possible implementation manners, the method further includes: sending second indication information, the second indication information comprising information indicating a time granularity of the amount of time deviation.

It should be understood that the time granularity may be information used to characterize the time unit or time accuracy, and the information of the time granularity may be predefined by a pre-configuration or protocol.

Through the technical scheme, the base station sends the information of the delta T to the terminal equipment, and the terminal equipment corrects the time information according to the information of the delta T. The base station may transmit information of the timing deviation amount Δ T accumulated between the radio frame timing system and the time system of the external clock to the terminal device. Specifically, the base station may load indication information including information of Δ T into the reference signal, for example, take a time deviation amount contained in the indication information as an input parameter of a sequence generation or resource mapping process of the reference signal, so that the terminal device acquires the information of the time deviation amount from the received reference signal; or the base station may send the time offset amount to the terminal device through DCI, MAC CE, or RRC signaling. And after receiving the indication information, the terminal equipment corrects the time information according to the acquired information of the delta T, adds or subtracts the time information and the time deviation amount, and takes the operation result as new time information. The timing error between a wireless frame timing system and the external clock timing can be reduced, and the accuracy of time synchronization between the terminal equipment and the base station is improved.

In a second aspect, a communication method is provided, including: receiving indication information, wherein the indication information comprises information used for indicating the time deviation amount before and after clock updating; and correcting the time information according to the indication information.

According to the technical scheme, the terminal equipment receives the information of the time deviation amount sent by the base station, and corrects the time information according to the information of the delta T, so that the time information of the terminal equipment can be updated in time, the validity of the reference time is guaranteed, the timing error caused by periodic updating of an external clock is reduced, and the accuracy of time synchronization of the terminal equipment and the base station is improved.

With reference to the second aspect, in some implementations of the second aspect, the indication information is carried in a reference signal.

With reference to the second aspect and the foregoing implementations, in some possible implementations, the sequence of reference signals is generated according to the time offset amount; or

With reference to the second aspect and the foregoing implementation manners, in some possible implementation manners, the indication information is carried in downlink control information DCI, a media access control element MAC CE, or radio resource control RRC signaling.

With reference to the second aspect and the foregoing implementation manners, in some possible implementation manners, modifying the time information according to the indication information includes:

acquiring a time deviation amount according to the indication information;

and adding or subtracting the time information and the time deviation amount, and taking the operation result as new time information.

Specifically, the terminal device may correct the time of the time system of the clock module according to the indication information; or correcting the derived time under the wireless frame timing system according to the indication information; or correcting the calculation result in the time synchronization process according to the indication information.

With reference to the second aspect and the foregoing implementation manners, in some possible implementation manners, the method further includes: sending second indication information, the second indication information comprising information indicating a time granularity of the time deviation amount.

In a third aspect, a communication device is provided, which has the function of implementing the network equipment (e.g. base station) in the method design of the first aspect. These functions may be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more units corresponding to the above functions.

In a fourth aspect, a communication device is provided, which has the function of implementing the terminal equipment in the method design of the second aspect. These functions may be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more units corresponding to the above functions.

In a fifth aspect, a network device is provided that includes a transceiver and a processor. Optionally, the network device further comprises a memory. The processor is configured to control the transceiver to transmit and receive signals, the memory is configured to store a computer program, and the processor is configured to retrieve from the memory and execute the computer program, so that the network device performs the method of the first aspect or any one of the possible implementation manners of the first aspect.

In a sixth aspect, a terminal device is provided that includes a transceiver and a processor. Optionally, the terminal device further comprises a memory. The processor is configured to control the transceiver to transmit and receive signals, the memory is configured to store a computer program, and the processor is configured to call and run the computer program from the memory, so that the terminal device executes the method of the second aspect or any one of the possible implementation manners of the second aspect.

In a seventh aspect, a communication system is provided, which includes the network device of the third aspect and the terminal device of the fourth aspect; alternatively, the system includes the network device of the fifth aspect and the terminal device of the sixth aspect.

In an eighth aspect, a communication apparatus is provided, which may be a network device designed by the method described above, or a chip disposed in the network device. The communication device includes: a processor, coupled to the memory, and configured to execute the instructions in the memory to implement the method performed by the network device in the first aspect or any one of the possible implementations of the first aspect. Optionally, the communication device further comprises a memory. Optionally, the communication device further comprises a communication interface, the processor being coupled to the communication interface.

When the communication device is a network device, the communication interface may be a transceiver, or an input/output interface.

When the communication device is a chip configured in a network device, the communication interface may be an input/output interface.

Alternatively, the transceiver may be a transmit-receive circuit. Alternatively, the input/output interface may be an input/output circuit.

In a ninth aspect, a communication apparatus is provided, which may be a terminal device designed by the above method, or a chip provided in the terminal device. The communication device includes: a processor, coupled to the memory, and configured to execute the instructions in the memory to implement the method performed by the terminal device in the second aspect or any one of the possible implementations of the second aspect. Optionally, the communication device further comprises a memory. Optionally, the communication device further comprises a communication interface, the processor being coupled to the communication interface.

When the communication device is a terminal device, the communication interface may be a transceiver, or an input/output interface.

When the communication device is a chip configured in a terminal device, the communication interface may be an input/output interface.

In a tenth aspect, there is provided a computer program product comprising: computer program code which, when run on a computer, causes the computer to perform the method of the above-mentioned aspects.

In an eleventh aspect, a computer-readable medium is provided, which stores program code, which, when run on a computer, causes the computer to perform the method of the above-mentioned aspects.

Drawings

Fig. 1 is a schematic architecture diagram of a mobile communication system suitable for use in the embodiments of the present application.

Fig. 2 is a schematic diagram of time synchronization between a base station and a terminal device according to an embodiment of the present application.

Fig. 3 is a timing diagram in two time reference frames according to an embodiment of the present application.

Fig. 4 is a schematic diagram of fluctuation of the deviation under two time reference frames provided by the embodiment of the present application.

Fig. 5 is a schematic diagram illustrating an example of a method for correcting time information according to an embodiment of the present application.

Fig. 6 is a schematic diagram of an example resource mapping method for reference signals according to an embodiment of the present disclosure.

Fig. 7 is a schematic diagram of an example of a communication device according to an embodiment of the present application.

Fig. 8 is a schematic diagram of another communication device provided in the embodiment of the present application.

Fig. 9 is a schematic diagram of an example network device according to an embodiment of the present application.

Fig. 10 is a schematic diagram of another example of a terminal device according to an embodiment of the present application.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

The technical scheme of the embodiment of the application can be applied to various communication systems, for example: a Long Term Evolution (LTE) system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD) system, a fifth generation (5th generation, 5G) mobile communication system, a New Radio (NR) communication system, a future mobile communication system, and the like.

Fig. 1 is a schematic architecture diagram of a mobile communication system suitable for use in the embodiments of the present application. As shown in fig. 1, the mobile communication system 100 may include a radio access network device 110 and at least one terminal device (e.g., terminal device 120 and terminal device 130 in fig. 1). The terminal equipment is connected with the wireless access network equipment in a wireless mode. The terminal equipment may be fixed or mobile. Fig. 1 is a schematic diagram, and other network devices, such as a wireless relay device and a wireless backhaul device, may also be included in the communication system, which are not shown in fig. 1. The embodiments of the present application do not limit the number of the radio access network devices and the terminal devices included in the mobile communication system.

In the mobile communication system 100, the radio access network device 110 is an access device that the terminal device accesses to the mobile communication system wirelessly. The radio access network device 110 may be: a base station, an evolved node b (eNB), a home base station, an Access Point (AP), a wireless relay node, a wireless backhaul node, a Transmission Point (TP), a Transmission and Reception Point (TRP) in a wireless fidelity (WIFI) system, and the like, and may also be a gNB in an NR system, or may also be a component or a part of a device constituting the base station, such as a Central Unit (CU), a Distributed Unit (DU), or a baseband unit (BBU). It should be understood that, in the embodiments of the present application, there is no limitation on the specific technology and the specific device form adopted by the radio access network device. In this application, a radio access network device is referred to as a network device for short, and if no special description is provided, network devices are referred to as radio access network devices in this application. In this application, the network device may refer to the network device itself, or may be a chip applied to the network device to complete a wireless communication processing function.

The terminal equipment in the mobile communication system 100 may also be referred to as a terminal, a User Equipment (UE), a Mobile Station (MS), a Mobile Terminal (MT), and the like. The terminal device in the embodiment of the present application may be a mobile phone (mobile phone), a tablet computer (Pad), a computer with a wireless transceiving function, or a wireless terminal applied to Virtual Reality (VR), Augmented Reality (AR), industrial control (industrial control), unmanned driving (self driving), remote medical (remote medical), smart grid (smart grid), transportation safety (transportation safety), smart city (smart city), and smart home (smart home). The terminal device and the chip applicable to the terminal device are collectively referred to as a terminal device in the present application. It should be understood that the embodiment of the present application does not limit the specific technology and the specific device form adopted by the terminal device.

In fig. 1, the network device 110 may serve as a centralized controller for the

terminal devices

120 and 130, and provide a time synchronization source for the

terminal devices

120 and 130, that is, send time information to the

terminal devices

120 and 130, so that the

terminal devices

120 and 130 in a cell maintain time synchronization with the network device 110, and indirectly meet a time synchronization requirement between the

terminal devices

120 and 130. It should be understood that, in the embodiments of the present application, a base station is taken as a network device, and time synchronization between the base station and a terminal device is taken as an example to be described in detail, that is, the base station is taken as a master clock node, and the terminal device is taken as a slave clock node, and it is understood that the method of the embodiments of the present application can also be used in more various network topologies. Besides time synchronization between the base station and the terminal device, the method may also be applied to other application scenarios, for example, device to device (D2D) and other application scenarios related to time synchronization, where the master clock node is the terminal device and the slave clock node is the terminal device, and the method of the embodiment of the present application may also be used to implement time synchronization. This is not limited by the present application.

In the time synchronization process, the base station may periodically transmit time information to the terminal device through a System Information Block (SIB), for example, the time information may be transmitted through an SIB 16. In the embodiment of the present application, time information of a time system of an external clock of a base station is represented as T_ref，T_refMay represent time information indicated by a base station at a specific time point (e.g., the start or end boundary of the SI window in which the SIB16 message is located) during operation, and T_refIs clocked under the time system of the clock module of the base station. It should be understood that T_refThe time information may be time information of UTC or GNSS, or time information operating according to a proprietary standard, for example, time information defined inside a local area network. This application includes but is not limited to.

Currently, in LTE, the granularity of system message transmission by a base station is 10 milliseconds (ms), and the configurable transmission period is 80ms to 5120 ms. However, as described in the background art, different terminal devices may need different time synchronization accuracies and different time synchronization periods in different application scenarios, and therefore, the time synchronization method for sending time information through system messages cannot provide a high-accuracy time synchronization service for different terminal devices.

At present, the Institute of Electrical and Electronics Engineers (IEEE) 1588 protocol defines a Precision Time Protocol (PTP), and its basic function is to enable a distributed communication network to have strict timing synchronization, and to implement time synchronization by means of application layer packet interaction. In practical application, IEEE1588 is a master-slave synchronization system, and a master clock node can be equivalent to a cell base station, and a slave clock node can be equivalent to a terminal device. For example, in the time synchronization process between the base station and the terminal device, the base station periodically issues a synchronization message (sync message) to the terminal device, and records the time T when the base station sends the sync message₁And will contain T₁Sending the timestamp information to the terminal equipment; the terminal equipment acquires the related synchronous message and the timestamp information T through the message interaction with the base station₁And recording the time T of receiving the sync message₂(ii) a The terminal device sends a reply message (delay response message) to the base station, and records the time T of sending the delay response message₃(ii) a The base station records the time T of receiving the delay response message₄Will contain T₄The timestamp information of (2) is sent to the terminal device. Through the message interaction process introduced above, the terminal device obtains T₁、T₂、T₃、T₄And according to T₁、T₂、T₃、T₄The time offset or delay between the terminal device and the base station is calculated. Specifically, the calculation can be performed by the formulas (1-a) and (1-b).

Or calculating the wireless signal transmission time between the base station and the terminal, wherein the specific calculation formula is as follows

Wherein, the offset is used for representing the time deviation between the terminal device and the base station, namely the time deviation between the master clock node and the slave clock node; delay is used to indicate the transmission time offset of the wireless signal from the base station to the terminal device. The terminal device may adjust the time information of the terminal device according to the calculated offset or delay, so as to achieve time synchronization with the base station. The above process is a time synchronization scheme designed for the application layer of a wired system. For future industrial control systems using wireless communication systems, in order to provide high-precision time synchronization services, the wireless communication systems need to introduce a time synchronization technology in the IEEE1588 protocol.

In a wireless system, when a time synchronization technology in an IEEE1588 protocol is used for high-precision time synchronization, a terminal needs to acquire a sending time T of a sync message of each synchronization flow₁Time information of, it should be understood that, here, T₁Is relative to T_refThe base station records the time at which the sync message is sent.

In LTE, time information T of a time system of a base station_refThe SIB16 is carried in the SIB16, but the SIB16 is a broadcast message, and the transmission time of the SIB16 cannot be directly used as the time T at which the sync message is transmitted to a specific terminal₁The terminal device can be according to T_refAnd radio frame timing to derive T₁For the purpose of distinguishing, the sending time of the derived synchronous message is marked as T₁' i.e. time information T of the time system of the base station clock module_refAs a time reference point of a radio frame, T is obtained by formula (2)₁′。

T₁′＝T_ref+n×t；·················(2)

Wherein, T_refIs the time information of the reference point under the time system of the clock module,n is the number of time units from the sending time to the reference point, n is a positive integer, n can be predefined by a system or a protocol, and n can also be the number of terminal equipment configured by the base station through a high-level signaling; or n may be signaled to the terminal device by the base station through physical layer signaling. In the present application, the physical layer signaling may be Downlink Control Information (DCI). The present application does not limit the manner of obtaining n. t is the time length corresponding to a time unit. In the present application, a time unit may be a radio frame, or a subframe, or a slot, or an Orthogonal Frequency Division Multiplexing (OFDM) symbol. One radio frame corresponds to 10ms, one subframe corresponds to 1ms, 1 LTE slot corresponds to 0.5ms, and the time length of one NR slot is determined by the subcarrier spacing, which is not limited in the present application. In NR, T_refMay be carried in system broadcast messages or in multicast or unicast messages.

It should be understood that the time when the base station sends the sync message is recorded is equivalent to the time when the start boundary or the end boundary of the time unit corresponding to the sync message is recorded. Similarly, the time at which the base station sends a signal, the terminal device sends a signal, or receives a signal is recorded in this standard. Here, the time corresponding to the start boundary or the end boundary of the time unit corresponding to the sync message may be understood as a time corresponding to the start subframe, the start slot, or the start symbol, or may be a time corresponding to the end subframe, the end slot, or the end symbol. This is not limited by the present application.

Theoretically, if the derived transmission time T of the sync message₁' time information T of time system with base station₁Remain consistent, then T may be used₁' calculating offset according to formula (1-a), or calculating delay according to formula (1-b), and correcting time information of the terminal device according to the offset or the delay, thereby achieving time synchronization with the base station. However, in practical applications, T₁' and T₁With a certain deviation therebetween, is denoted as Δ T ═ T₁-T₁'. Lower pair of T₁' and T₁Origin of deviation Δ T betweenFor analysis.

Fig. 2 is a schematic diagram of time synchronization of a base station and a terminal device in a wireless communication system. As shown in fig. 2, the base station includes at least two modules, an external clock module 201 and a communication module 202. The external clock module 201 of the base station may communicate with an external clock source, and periodically obtain time information from the external clock source, such as time information of UTC or GNSS, or time information of a time system running in a private standard, for calibrating the time information of the time system of the base station. The terminal device also includes two modules, a clock module 203 and a communication module 204, wherein the clock module 203 cannot directly acquire the time information of the external clock, and needs to communicate with the communication module 202 of the base station through the communication module 204, so as to further perform time synchronization according to the time information of the time system of the external clock module 201 of the base station. The communication module 202 of the base station and the communication module 204 of the terminal device may communicate with each other based on a typical communication protocol, for example, the 3rd generation Partner Project (3 GPP) protocol.

As can be seen from the above description, there are two timing systems in the base station, one is a time system of an external clock, which performs timing according to a time system defined by international standards or a time standard defined by a local area network; one is a radio frame timing system that times according to radio frame number, slot number, etc. The two timing systems run on respective hardware modules, and inevitably, there is a difference between the two. Specifically, the external clock module 201 of the base station is calibrated to cause the time system to jump in the order of 100 nanoseconds (ns), and the radio frame of the radio frame timing system of the communication module 202 of the base station is continuously changed all the time, so that the deviation between the two timing systems is continuously accumulated as time increases.

In addition, since the sampling circuits of the external clock module 201 and the communication module 202 of the base station may be independent of each other, the sampling frequency of the external clock time system and the wireless frame timing system of the communication module may also have a certain deviation. In Technical Specification (TS) 36.104 of 3GPP, it is specified that the carrier frequency error requirement of a transmission signal does not exceed ± 0.1 ppm. Similarly, assuming that the sampling frequency of the base station and the external clock frequency also have the same error requirement ± 0.1ppm, the frequency error range of the external clock module and the communication module should be within ± 0.2 ppm. The amount of timing drift caused by frequency error will also become larger as time increases.

Furthermore, as shown in fig. 3, if there is a difference between the time granularity of the external clock module and the radio frame timing system, for example, the radio frame duration of the wireless communication system is 10ms, and the observation result of the external clock on the radio frame may be 10ms ± 2 ns. The amount of timing drift caused by the difference in time granularity becomes increasingly large as time increases.

In the present application, a time counting system using an external clock is referred to as a time system using a clock module, a time counting system using a 3GPP communication system is referred to as a radio frame timing system, and the transmission time T of the sync message obtained by the equation (2) is shown₁' is the timing result of the radio frame timing system, the sending time T of the sync message recorded by the base station₁Is the time recorded by the time system based on the clock module, T₁' and T₁There is a certain deviation.

Fig. 4 is a diagram showing fluctuations in timing offsets between a time system of an external clock of a base station and a radio frame timing system. As shown in fig. 4, the horizontal axis represents the radio frame timing time of the base station, and the vertical axis represents the deviation Δ T ═ T of the two timing systems of the base station₁-T₁' the black solid line of the ramp-up represents the accumulation of the deviation amount due to the frequency error, and the step change of the black solid line represents the change of the time deviation amount caused by the periodic calibration update of the time system of the base station and the external clock.

As can be seen from the above analysis, T is the cause of₁' and T₁The time deviation amount Delta T between, the time (T) of sending the sync message determined by the terminal equipment₁') and the actual transmission time (T) of the sync message₁) There is a certain error between them, and as time increases, the error increases continuously, resulting in that the terminal equipment and the base station cannot accuratelyTime synchronization is maintained. And the time deviation amount of the time system relative to the clock module is required to be within +/-500 ns in the high-precision time synchronization service. Therefore, the present application provides a method for correcting time information, which determines a time deviation Δ T of a wireless frame timing system and a time system of an external clock through a base station, and sends the time deviation Δ T to a terminal device, and the terminal device corrects the time information according to the Δ T, updates the time information in time, and realizes time synchronization with the base station.

Fig. 5 is a schematic diagram illustrating an example of a method for correcting time information according to an embodiment of the present application. Each step of the method 500 will be described in detail with the base station as the master clock node and the terminal device as the slave clock node. It will be appreciated that the master and slave clock nodes may also be other communication devices, for example, the nodes of the master and slave clock nodes may be different terminal devices.

It should be understood that, in the embodiment of the present application, the method 500 is described with the terminal device and the base station as the execution subjects. By way of example and not limitation, the execution subject of method 500 may also be a chip applied to a terminal device and a chip applied to a base station.

S501, the base station determines the time deviation amount before and after the clock updating.

Specifically, the time offset is an offset between the times recorded under different timing systems at the occurrence time of a specific event, that is, an offset between a first time recorded based on a first time coordinate system and a second time recorded based on a second time coordinate system, wherein the specific event may refer to an unambiguous event occurring at the base station, such as transmission of a specific signal, transmission of a specific data packet, timing trigger of a specific frame (such as a null frame), and the like; the first time is the occurrence time of the specific event in a first time coordinate system, the second time is the occurrence time of the specific event in a second time coordinate system, and the first time coordinate system is different from the second time coordinate system.

Specifically, the first time coordinate system may be a coordinate system based on a time system of the external clock module, and the second time coordinate system may be a coordinate system based on a radio frame timing system, and the time deviation amount is a timing deviation amount between the second time based on the radio frame timing system and the first time based on the external clock timing.

It is understood that with T_refAs a reference time, the base station transmits a first downlink signal to the terminal equipment, and records the transmission time T of the first downlink signal₁. Can understand T₁Is the transmission time, T, of the first downlink signal in a first time coordinate system₁' is the transmission time of the first downlink signal in a second time coordinate system, the first time coordinate system being different from the second time coordinate system, resulting in T₁And T₁There is a deviation between.

Furthermore, T_refMay multiplex protocol existing messages, e.g., transmitted using SIB 16; or use other Radio Resource Control (RRC) messages, which is not limited in this application. In particular, if the time T is referenced_refIs transmitted through SIB16, the reference time T_refThe time when the end frame boundary of the System Information (SI) window of SIB16 arrives at the transmit antenna port is transmitted for the base station. In addition, the base station may periodically transmit T_refSpecifically, if the reference time information is transmitted through the SIB16, the transmission period may be 80ms to 5120 ms. It should be understood that the first downlink signal is a signal transmitted by the base station for the terminal device, such as a synchronization signal, a reference signal, a data message, and so on. The first downlink signal is not limited in form in the present application.

Base station at T₁The first downlink signal is sent to the terminal device at a time, accordingly, the terminal device receives the first downlink signal sent by the base station, and the terminal device can record the time T of receiving the first downlink signal₂. It should be understood that the transmission time of the first downlink signal is T here₁The time recorded by the base station with reference to the time system (first time coordinate system) of the external clock; similarly, the time T when the terminal device receives the first downlink signal₂And the time recorded by taking the time system of the clock module of the terminal equipment as a reference.

It should be understood that,with the radio frame timing system of 3GPP as a reference, the base station and the terminal device can know the time of transmitting the first downlink signal, and the derived time of transmitting the first downlink signal is denoted as T as before₁', T is known from the formula (2)₁′＝T_ref+n×t。

In S501, the base station records the transmission time T of the first downlink signal₁And T₁' so that the time deviation amount deltat-T can be determined₁-T₁′。

For example, assume reference point time T_ref10ms, a transmission time T in a first time coordinate system₁Recorded as 12.001 ms; in a radio frame timing system, the first downlink signal is transmitted through 2 subframes, the time length of each subframe is 1ms, and the base station records T in a second time coordinate system₁′＝T_ref+ n × T +2 × 1 ms-12 ms, i.e. T₁' is 12 ms. The base station may now determine the time offset Δ T ═ T₁-T₁′＝0.001ms。

It will be appreciated that based on the foregoing analysis of errors in the two time reference coordinate systems, Δ T includes the amount of accumulated time deviation caused by external clock module hop variations and clock frequency deviations.

It should also be understood that when the base station is in operation but does not transmit the first downlink signal, the base station may take a point as a reference point, and the time of the point in the time system of the clock module is recorded as T₁Corresponding to a time T in a radio frame timing system₁', determining the time deviation amount DeltaT as T₁-T₁′。

It should also be understood that in determining the time deviation Δ T, the time information T of the time system of the clock module of the base station can be at the last reference point_refCalculating as a reference; or, with the last time offset Δ T^oldCorrected time information

And calculating the time deviation amount of the current time as a reference point time reference. May be specifically according to

And calculating to obtain the time deviation value of the current time. Current time information

When the accuracy is not high, Δ T may be used^oldSupplementHigh precision part information. For example, when

When carried in the SIB16 message, the SIB16 message indicates

Is of the order of 10ms, Δ T^oldThe amount of time offset represented is 0.001ms, which can be based on Δ T^oldCorrection

I.e. new

Is 10.001 ms. Here will be Δ T^oldAs a

Time information of the high-precision part.

S502, the base station sends indication information, and the indication information comprises information used for indicating the time deviation amount.

Specifically, the base station sends indication information including information of the time deviation amount to the terminal device, and the terminal device receives the indication information and determines the time deviation amount through the indication information.

Optionally, the base station sends second indication information, which includes information indicating the time granularity of the time deviation amount.

It should be understood that the time granularity may be information used to characterize the time unit or time accuracy, and the information of the time granularity may be predefined by a pre-configuration or protocol. For example, the base station and the terminal device agree in advance on the time offset amount calculated at a granularity of 100 ns. Or, the time granularity information may be dynamically configured, and the time granularity may be dynamically adjusted according to needs, and such a configuration may save bit overhead.

It should also be understood that the second indication information may be a part of the aforementioned information indicating the time deviation amount, or may be transmitted separately from the aforementioned indication information.

Two ways of sending the indication information are described below.

In a first mode

The indication information is carried in the reference signal.

Alternatively, the reference signal may multiplex an existing downlink reference signal or use a dedicated reference signal. Such as a cell-specific reference signal (CRS), a demodulation reference signal (DMRS), a multicast single frequency reference signal (MBSFN RS), a Positioning Reference Signal (PRS), and a channel state information reference signal (CSI-RS). The present application does not limit the type of reference signal.

It should be understood that the indication information includes information for indicating the time deviation amount, and to implement the transmission of the indication information to the terminal device, the time deviation amount contained in the indication information may be used as an input parameter for the generation of the sequence of reference signals or the resource mapping process, so that the terminal device acquires the information of the time deviation amount from the received reference signals. Three methods for carrying the indication information in the reference signal and sending the indication information to the terminal device are specifically listed below.

(1) Generation procedure of sequence of reference signals

Optionally, the sequence of reference signals is generated according to the amount of time deviation.

In particular, the time offset may be a parameter of a sequence generating function of the reference signal. It is to be understood that the participation of the time offset in the sequence of generating the reference signal, i.e. the participation of the time offset in the calculation process of the sequence generation, is to be achieved. The base station may select generation of the reference signal sequence r (m) based on the amount of time offset, e.g.

r(m)＝x_seq(m；[ΔT/L])；………………………………………………(3)

Where L is the granularity of the time offset, m represents the index of the element in the sequence, x_seqFunction representing sequence generation of reference signal, [ Delta T/L]Represents a function that rounds Δ T based on the particle size L, which may be, but is not limited to, rounding down, rounding up, or rounding up.

Optionally, the base station may further perform phase rotation processing on the sequence of reference signals according to the time offset as shown in equation (4).

Where r (m) is a sequence of the original reference signal, and r' (m) is a sequence of the reference signal subjected to the phase rotation processing; m represents the index of an element in the sequence; α and C are fixed constants, defined by the protocol, and N is the fast Fourier Transform (FT) size.

(2) Mapping procedure of sequence of reference signals

Optionally, the sequence of the reference signals is mapped to time-frequency resources according to the time offset. Specifically, the corresponding processing may be performed according to equation (5).

a_k,l＝βr(m)；………………………………(5)

Wherein k is f_mapping(m,. DELTA.T) and/or l ═ g_mapping(m；ΔT)。a_k,lRepresents content carried on a kth Resource Element (RE) on the ith symbol; β is a constant, representing the power level; f. of_mapping(m,. DELTA.T) and g_mapping(m; Δ T) is a resource mapThe time offset is a parameter in the mapping function.

As shown in fig. 6, the reference signal carrying the indication information may be time division multiplexed or frequency division multiplexed with other reference signals.

Or, the RS for carrying the Δ T occupies a part of resources of other reference signals, thereby implementing sending the Δ T to the terminal device. For example, the other reference signal may be a Tracking Reference Signal (TRS).

It should be understood that, the present application is not limited to the manner of resource mapping, and for any manner of resource mapping, the terminal device may adopt a corresponding detection algorithm when receiving the RS carrying Δ T, and obtain the time offset included in the indication information.

The indication information can be carried in the reference signal through the two modes, and no matter the sequence of the reference signal is generated according to the time deviation amount or the time-frequency resource mapping is carried out according to the time deviation amount, the terminal equipment can obtain the indication information by detecting the reference signal after receiving the reference signal, so that the time deviation amount is determined.

The method for sending the information comprising the time deviation amount through the reference signal can send the indication information to the terminal equipment by utilizing the multicast message of the base station, so that the mode for sending the indication information is more flexible; meanwhile, the time information of the terminal equipment can be corrected in time under the condition of not influencing the period of broadcasting and sending the time information in the cell, and the validity of the reference time is ensured, so that the time synchronization with the base station is realized.

Mode two

In another possible implementation manner, the indication information is carried in downlink control information DCI, a medium access control element (MAC CE), or radio resource control RRC signaling.

It should be understood that, by using the above three messages to carry the information of the time offset amount, the required response time is increased sequentially. Specifically, for example, the response time required for DCI to carry information of Δ T is shortest, and the response time required for RRC signaling to carry information of Δ T is longest; for the modification degree of the protocol, the modification degree of the information carrying the Δ T by the DCI to the protocol is the largest, and the modification degree of the information carrying the Δ T by the RRC signaling to the protocol is the smallest. Therefore, in the practical application process, the timeliness of the time offset and the modification degree of the protocol are considered, and the time offset can be considered to be transmitted by using the MAC CE.

By the method for transmitting the indication information, the information of the time deviation amount can be transmitted to the terminal equipment by using DCI, MAC CE or RRC signaling, and the accuracy of time synchronization between the terminal equipment and the base station is improved.

The above describes the type used for carrying the indication information, and there are many possible cases of the sending timing of the indication information, or the sending mode of the indication information. The following three possible cases are specifically enumerated.

(1) Periodic transmission

The base station may periodically transmit the indication information to the terminal device. For example, a certain transmission period may be configured for the base station, or the base station may select an appropriate detection period according to its hardware condition, and periodically transmit the indication information including the time offset to the terminal device.

It should be appreciated that the period of time that the base station detects the amount of time offset and transmits the amount of time offset may be different. For example, the base station may detect the time offset at a predetermined time, but the time offset is transmitted at a predetermined cycle, which is not limited in the present application.

(2) Signaling notification

In a possible mode, the base station can inform the terminal device to start receiving the indication information through a high-level signaling, and the terminal device receives the indication information according to a pre-configured period; the base station may also inform the terminal device to stop receiving the indication information through higher layer signaling. The higher layer signaling may multiplex the activation and deactivation messages of the time synchronization function, respectively.

(3) Dynamic triggering

In another possible manner, when the time deviation is greater than or equal to the preset first threshold, the base station sends the indication information to the terminal device.

Specifically, the base station dynamically selects whether to send the indication information according to the size of Δ T: the base station determines a first threshold, and when the value of the delta T is greater than or equal to the first threshold, namely the time synchronization result possibly cannot meet the current requirement, the base station sends delta T information to the terminal equipment for correcting the time information. It should be appreciated that the first threshold may be a constant preset by the protocol, or a constant determined by the time synchronization accuracy requirement.

And S503, the terminal equipment corrects the time information according to the indication information.

Specifically, after receiving the indication information, the terminal device corrects the time information according to the indication information. The terminal equipment can acquire the time deviation amount according to the indication information; and adding or subtracting the time information and the time deviation amount, and taking the operation result as new time information.

Alternatively, the terminal device may implement time synchronization with the base station by modifying time information of the time system, or modifying downlink signal transmission time calculated by the radio frame timing system, or modifying calculation results of the aforementioned formula (1-a) or (1-b). The following are listed:

(1) terminal equipment corrects time of time system of clock module

And the terminal equipment corrects the time information of the reference point of the time system of the clock module according to the time deviation value. For example, the terminal device may correct the time information T of the time system according to Δ T_refThe correction can be made according to equation (6).

The terminal equipment is to

As time information of a new reference point of the time system of the clock module.

Is the time information of the reference point of the time system of the clock module transmitted by the last base station.

(2) Terminal equipment amends downlink signal sending time calculated under radio frame timing system

And the terminal equipment corrects the time of the wireless frame timing system according to the time deviation amount, and for the first downlink signal, the terminal equipment corrects the time of the predicted transmission time of the first downlink signal. Specifically, the terminal device may modify the transmission time T of the first downlink signal timed in the radio frame timing system according to equation (7)₁′，

T₁ ^new＝T₁′+ΔT；………………………………(7)

Wherein, T₁ ^newIs the corrected time, T, of the radio frame timing system₁The 'time correction' radio frame times the system time. Will be corrected T₁ ^newAs T₁And then calculates the offset according to formula (1) or calculates the delay according to formula (1-b), thereby further completing the time synchronization process.

(3) Correcting calculation results in time synchronization process

And the terminal equipment corrects the time synchronization calculation result according to the time deviation amount. For example, after the terminal device receives the indication information, the acquired time deviation amount Δ T is saved, and T is acquired₃、T₄After the time information of (1), Δ T is added to the calculation formula of time synchronization as correction information directly. Specifically, in the time synchronization process between the terminal device and the base station, the terminal device may calculate the time offset according to equations (1-a) and (2), take the influence of the time offset Δ T into consideration, and then correct the offset according to the Δ T, specifically by

Make corrections according to [ offset ]]_modifyAnd carrying out time synchronization of the terminal equipment and the base station.

Furthermore, delay can be understood as [ offset ]]_modifyOf systems for advancing or retarding the time of the clock module of the terminal equipmentAnd (5) time deviation. Specifically, the terminal device may correct the delay according to the Δ T by taking into account the influence of the time deviation amount Δ T according to the signal transmission delay time delay calculated by the formulas (1-b) and (2), specifically by

And (6) correcting. Thereby according to [ delay]_modifyAnd the formula (2) can obtain the time T displayed by the time system of the base station when the downlink signal reaches the terminal equipment_2,gNB＝T₁+[delay]_modifyThe terminal device is then based on T_2,gNBThe time system of the terminal device is reset.

It should be understood that, the present application is not limited to the way that the terminal device corrects the time information of the wireless frame timing system according to the Δ T, and the purpose of the present application is to enable the terminal device to update the time information by correcting the Δ T, so as to avoid the accumulated time deviation caused by the external clock module jump and the clock frequency deviation from affecting the time synchronization, thereby implementing the time synchronization between the terminal device and the base station.

In addition, the time correction is performed according to the time synchronization technique in IEEE1588 protocol as formula (1), except that the time T for sending the synchronization message is obtained as described in the embodiments of the present application₁In addition, T is required₂、T₃And T₄Time information of (2). Wherein, T₂Time of receiving a synchronization message for a terminal device, T₃The time at which the delay response message is sent for the terminal device, both of these pieces of time information are explicitly known to the terminal device. T is₄The time information of (2) is transmitted to the terminal device by the base station, and the transmission form can be various, which is not listed here. For example, the base station records the time T when the terminal equipment sends the delayresponse message₄And will T₄The method for sending the delta T is also used for sending the delta T to the terminal equipment.

Through the method for sending the information including the delta T and correcting the time information, the delta T information is sent to the terminal equipment through the base station, and the terminal equipment corrects the time information according to the delta T information. The base station may transmit information of the timing deviation amount Δ T accumulated between the radio frame timing system and the time system of the external clock to the terminal device. Specifically, the base station may load indication information including information of Δ T into the reference signal, for example, take a time deviation amount contained in the indication information as an input parameter of a sequence generation or resource mapping process of the reference signal, so that the terminal device acquires the information of the time deviation amount from the received reference signal; or the base station may send the time offset amount to the terminal device through DCI, MAC CE, or RRC signaling. And after receiving the indication information, the terminal equipment corrects the time information according to the acquired information of the delta T, adds or subtracts the time information and the time deviation amount, and takes the operation result as new time information. The timing error between a wireless frame timing system and the external clock timing can be reduced, and the accuracy of time synchronization between the terminal equipment and the base station is improved.

The method for correcting time information according to the embodiment of the present application is described in detail above with reference to fig. 2 to 6. Hereinafter, an apparatus for correcting time information according to an embodiment of the present application will be described in detail with reference to fig. 7 to 10.

Fig. 7 shows a schematic block diagram of a communication apparatus 700 according to an embodiment of the present application, where the apparatus 700 may correspond to (for example, may be applied to or is itself the base station described in the method 500, and each module or unit in the apparatus 700 is respectively configured to execute each action or process performed by the base station in the method 500, as shown in fig. 7, the communication apparatus 700 may include: a processing unit 710 and a communication unit 720.

The processing unit 710 is used to determine the amount of time offset before and after the clock update.

The communication unit 720 is configured to send indication information, which includes information indicating the time deviation amount.

Specifically, the processing unit 710 is configured to execute S501 in the method 500, the communication unit 720 is configured to execute S502 in the method 500, and the specific processes of the units executing the corresponding steps are already described in detail in the method 500, and are not repeated herein for brevity.

Fig. 8 shows a schematic block diagram of a communication apparatus 800 according to an embodiment of the present application, where the apparatus 800 may correspond to (for example, may be applied to or is itself a terminal device described in the foregoing method 500, and each module or unit in the apparatus 800 is respectively configured to execute each action or processing procedure executed by the terminal device in the foregoing method 500, as shown in fig. 8, the communication apparatus 800 may include: a communication unit 810 and a processing unit 820.

The communication unit 810 is configured to receive indication information including information indicating an amount of time deviation before and after clock updating.

The processing unit 820 is configured to modify the time information according to the indication information.

Specifically, the communication unit 810 is configured to execute S502 in the method 500, the processing unit 820 is configured to execute S503 in the method 500, and the specific processes of the units for executing the corresponding steps are already described in detail in the method 500, and are not repeated herein for brevity.

Fig. 9 is a schematic structural diagram of a communication device 900 according to an embodiment of the present application. As shown in fig. 9, the communication device 900 (e.g., a base station) includes a processor 910 and a transceiver 920. Optionally, the communication device 900 further comprises a memory 930. Wherein, the processor 910, the transceiver 920 and the memory 930 communicate with each other via the internal connection path to transmit control and/or data signals, the memory 930 is used for storing a computer program, and the processor 910 is used for retrieving and running the computer program from the memory 930 to control the transceiver 920 to transmit and receive signals.

The processor 910 is configured to execute the program codes stored in the memory 930 to implement the functions of the base station in the above-described method embodiments. In particular implementations, the memory 930 may be integrated with the processor 910 or may be separate from the processor 910. The transceiver 920 may be implemented by way of transceiver circuitry.

The communication device 900 may further include an antenna 940, configured to send out the downlink data or the downlink control signaling output by the transceiver 920 through a wireless signal, or send the uplink data or the uplink control signaling to the transceiver 820 for further processing after receiving the uplink data or the uplink control signaling.

It should be understood that the communication apparatus 900 may correspond to the base station in the method 500 according to the embodiment of the present application, and the apparatus 900 may also be a chip or a component applied to the base station. Moreover, each module in the apparatus 900 implements the corresponding flow in the method 500 in fig. 5, specifically, the memory 930 is configured to store a program code, so that when the processor 910 executes the program code, the processor 910 is controlled to execute the step S501 in the method 500, the transceiver 920 is configured to execute the step S502 in the method 500, and the specific process of each unit executing the corresponding step is described in detail in the method 500, which is not repeated herein for brevity.

Fig. 10 is a schematic structural diagram of a communication device 1000 according to an embodiment of the present application. As shown in fig. 10, the communication device 1000 includes a processor 1010 and a transceiver 1020. Optionally, the communication device 1000 further comprises a memory 1030. Wherein, the processor 1010, the transceiver 1020 and the memory 1030 communicate with each other via the internal connection path to transmit control and/or data signals, the memory 1030 is used for storing a computer program, and the processor 1010 is used for calling and running the computer program from the memory 1030 to control the transceiver 1020 to transmit and receive signals.

The processor 1010 is configured to execute the program codes stored in the memory 1030 to implement the functions of the terminal device in the above-described method embodiments. In particular implementations, the memory 1030 may be integrated with the processor 1010 or separate from the processor 1010. The transceiver 1020 may be implemented by way of transceiver circuitry.

The communication device 1000 may further include an antenna 1040, configured to send out the uplink data or the uplink control signaling output by the transceiver 1020 through a wireless signal, or send the received downlink data or the received downlink control signaling to the transceiver 1020 for further processing.

It should be understood that the apparatus 1000 may correspond to the terminal device in the method 500 according to the embodiment of the present application, and the apparatus 1000 may also be a chip or a component applied to the terminal device. Moreover, each module in the apparatus 1000 implements the corresponding flow in the method 500 in fig. 5, specifically, the memory 1030 is configured to store a program code, so that when the processor 1010 executes the program code, the processor 1010 is controlled to execute S503 in the method 500, the transceiver 1020 is configured to execute S502 in the method 500, and a specific process of each unit executing the corresponding step is described in detail in the method 500, which is not repeated herein for brevity.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and no further description is provided herein.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described device embodiments are merely illustrative, and the division of the unit is only one logical functional division, and there may be other division ways in actual implementation, for example, a plurality of units or components may be combined. In addition, the shown or discussed coupling or communication connections between each other may be indirect coupling or communication connections through some interfaces, devices or units.

In addition, functional units in the embodiments of the present application may be integrated into one physical entity, or each unit may correspond to one physical entity separately, or two or more units may be integrated into one physical entity.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

Claims

1. A method of communication, comprising:

determining the time deviation amount before and after the clock updating;

and sending indication information, wherein the indication information comprises the information of the time deviation amount.

2. The method of claim 1, wherein the indication information is carried in a reference signal.

3. The method of claim 2, wherein the sequence of reference signals is generated from the amount of time deviation; or

And the sequence of the reference signal is subjected to time-frequency resource mapping according to the time deviation value.

4. The method of claim 1, wherein the indication information is carried in Downlink Control Information (DCI), a media access control element (MAC CE), or Radio Resource Control (RRC) signaling.

5. The method according to any one of claims 1 to 4, wherein the sending the indication information comprises:

and when the time deviation is greater than or equal to a preset first threshold, sending the indication information.

6. The method according to any one of claims 1 to 5, further comprising:

sending second indication information, the second indication information comprising information indicating a time granularity of the time deviation amount.

7. A method of communication, comprising:

receiving indication information, wherein the indication information comprises information used for indicating the time deviation amount before and after clock updating;

and correcting the time information according to the indication information.

8. The method of claim 7, wherein the indication information is carried in a reference signal.

9. The method of claim 8, wherein the sequence of reference signals is generated based on the amount of time deviation; or

10. The method of claim 7, wherein the indication information is carried in Downlink Control Information (DCI), a media access control element (MAC CE), or Radio Resource Control (RRC) signaling.

11. The method according to any one of claims 7 to 10, wherein the modifying the time information according to the indication information comprises:

acquiring a time deviation amount according to the indication information;

12. The method according to any one of claims 7 to 11, further comprising:

13. A communications apparatus, comprising:

the processing unit is used for determining the time deviation amount before and after clock updating;

a communication unit configured to transmit indication information, the indication information including information indicating the time deviation amount.

14. The apparatus of claim 13, wherein the indication information is carried in a reference signal.

15. The apparatus of claim 14, wherein the sequence of reference signals is generated according to the amount of time deviation; or

16. The apparatus of claim 13, wherein the indication information is carried in Downlink Control Information (DCI), a media access control element (MAC CE), or Radio Resource Control (RRC) signaling.

17. The apparatus according to any of claims 13 to 16, wherein the communication unit is further configured to:

18. The apparatus according to any of claims 13 to 17, wherein the communication unit is further configured to send second indication information, the second indication information comprising information indicating a time granularity of the time deviation amount.

19. A communications apparatus, comprising:

a communication unit configured to receive indication information including information indicating an amount of time deviation before and after clock update;

and the processing unit is used for correcting the time information according to the indication information.

20. The apparatus of claim 19, wherein the indication information is carried in a reference signal.

21. The apparatus of claim 20, wherein the sequence of reference signals is generated according to the amount of time deviation; or

22. The apparatus of claim 19, wherein the indication information is carried in Downlink Control Information (DCI), a media access control element (MAC CE), or Radio Resource Control (RRC) signaling.

23. The apparatus according to any one of claims 19 to 22, wherein the processing unit is further configured to:

acquiring a time deviation amount according to the indication information;

24. The apparatus according to any of claims 19 to 23, wherein the communication unit is further configured to send second indication information, the second indication information comprising information indicating a time granularity of the time deviation amount.

25. A computer-readable storage medium, characterized in that it stores a computer program which, when executed, implements the method of any one of claims 1 to 12.

26. A chip system, comprising:

a memory to store instructions;

a processor configured to retrieve and execute the instructions from the memory, so that a communication device in which the system-on-chip is installed performs the method according to any one of claims 1 to 12.