WO2020001585A1 - Clock synchronisation method and apparatus - Google Patents

Abstract

Provided in the present application are a clock synchronisation method and apparatus, the method comprising: a network device receives an uplink signal of a terminal, determines the time deviation between the time the uplink signal actually arrived at the network device and a target arrival time of the uplink signal, and indicates the time deviation to the terminal by means of indication information; and, by means of the time deviation, the terminal corrects the clock of the terminal in order to ensure synchronisation with the clock of the network device. In the clock synchronisation method in the embodiments of the present application, a terminal implements clock synchronisation by means of a time deviation indicated by a network device, meeting the requirements for high precision clock synchronisation between the network device and the terminal.

Description

Method and device for clock synchronization

This application claims the priority of a Chinese patent application filed on June 28, 2018 with the Chinese Patent Office, application number 201810688385.3, and application name "A Method and Device for Clock Synchronization", the entire contents of which are incorporated herein by reference. in.

Technical field

The present application relates to the field of communications, and more particularly, to a method and apparatus for clock synchronization.

Background technique

In order to ensure the orthogonality of uplink transmission and avoid intra-cell interference, network devices require that the signals from different terminals in the same subframe but different frequency domain resources reach the network devices are basically aligned. As long as the network device receives the uplink data sent by the terminal within the range of cyclic prefix (CP), it can correctly decode the uplink data. Therefore, uplink synchronization requires that the signals from different terminals in the same subframe reach the network device at the same time. Falls within the scope of the cyclic prefix. In order to ensure synchronization on the receiving side (network device side), Long Term Evolution (LTE) proposes an uplink timing advance (TA) mechanism.

From the perspective of the terminal, the timing advance TA is essentially a time offset between the start time at which the terminal receives the downlink subframe and the start time at which the uplink subframe is transmitted. By properly controlling the TA of each terminal, the network device can control the time when uplink signals from different terminals reach the network device. For terminals that are far away from the network equipment, because there is a large transmission delay, it is necessary to send uplink data in advance than terminals that are closer to the network equipment.

The network device indicates the initial TA to the terminal when the terminal performs random access, and subsequently sends TA adjustments to the terminal from time to time through the TA command. Since the transmission of the TA adjustment depends on the implementation of the network device (can be sent or not) ), And the TA adjustment amount is to ensure the normal communication of the uplink data channel. If the terminal uses the TA adjustment amount to perform clock synchronization, it cannot meet the high-precision time synchronization requirements between the network device and the terminal.

Summary of the invention

In view of this, the present application provides a method and apparatus for clock synchronization to meet the high-precision clock synchronization requirements between network equipment and terminals.

According to a first aspect, a clock synchronization method is provided. The method includes: a terminal sending a first uplink signal to a network device; the terminal receiving first instruction information from the network device, the first instruction information used to indicate the The time difference between the time when the first uplink signal actually arrives at the network device and the time when the first uplink signal is expected to arrive at the network device; the terminal performs clock synchronization according to the time deviation.

It should be understood that the time when the first uplink signal is expected to reach the network device may also be understood as the target arrival time of the first uplink signal, or the time when the first uplink signal is expected to reach the network device may also be understood as the network device Or the time when the boundary of the first time unit calculated by the terminal is expected to reach the network device, the first time unit is a time unit that actually transmits the first uplink signal.

In some possible implementation manners, the time offset is a deviation between a sampling point at a time when the first uplink signal actually reaches the network device and a sampling point at a time when the first uplink signal is expected to reach the network device.

In the embodiment of the present application, the time unit may be a radio frame, a subframe, a time slot, a mini time slot (mini slot), an orthogonal frequency division division multiplexing (OFDM) defined in an LTE or 5G NR system. The symbol may also be a time window composed of multiple frames or subframes, such as a system information (SI) window.

The clock synchronization method in the embodiment of the present application sends a time offset to the terminal through the network device, which helps meet the high-precision clock synchronization requirement between the network device and the terminal.

With reference to the first aspect, in some possible implementation manners of the first aspect, the terminal receiving the first instruction information from the network device includes: at a second time unit, the terminal receiving the network device from the network device. First indication information; wherein the second time unit is the Nth time unit after the first time unit, or the second time unit is the Nth available time unit after the first time unit, or, The second time unit is a first available time unit after the Nth time unit, the first time unit is a time unit that actually transmits the first uplink signal, and N is a positive integer greater than or equal to 1.

In some possible implementation manners, N is configured by the network device, or N is predefined by the protocol.

In some possible implementation manners, the terminal receives the first indication information in a first time window after sending the first uplink signal.

In some possible implementation manners, a time length, an appearance period, and a time offset with respect to the first uplink signal of the first time window are configured by the network device or predefined by a protocol.

In some possible implementation manners, the terminal receives the network device and sends the first instruction information in a first period.

In some possible implementation manners, the network device receives the first uplink signal sent by the terminal in the first period.

With reference to the first aspect, in some possible implementation manners of the first aspect, the method further includes: adjusting, by the terminal, a sending advance of the second uplink signal according to the time offset.

With reference to the first aspect, in some possible implementation manners of the first aspect, the first indication information further includes information used to indicate time-frequency resources of the first uplink signal; or the first indication information further includes Information indicating frequency domain resources of the first uplink signal; or, the first indication information further includes information used to indicate time domain resources of the first uplink signal.

The method for clock synchronization in the embodiment of the present application helps the terminal to determine the time in the first indication information by carrying information about time domain resources and / or frequency domain resources of the first uplink signal in the first indication information. The deviation is obtained by the terminal sending a first uplink signal.

With reference to the first aspect, in some possible implementation manners of the first aspect, the method further includes that the terminal receives second instruction information from the network device, where the second instruction information includes a time indication for indicating the time deviation. Granular information.

In some possible implementation manners, the first indication information and the second indication information are carried in the same signaling.

In some possible implementation manners, the granularity of the time deviation is a positive integer number of nanoseconds (ns) or 2 ^μT _C or T _S.

In some possible implementation manners, the granularity of the time deviation is 100 ns, 50 ns, 10 ns, or 2 ^μT _C or T _S.

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

According to a second aspect, a clock synchronization method is provided. The method includes: a network device receives a first uplink signal from a terminal; the network device sends first instruction information to the terminal, where the first instruction information is used to indicate the first A time offset between the time when an uplink signal actually arrives at the network device and the time when the first uplink signal is expected to arrive at the network device, and the time offset is used by the terminal for clock synchronization.

It should be understood that the time when the first uplink signal is expected to reach the network device may also be understood as the target arrival time of the first uplink signal, or the time when the first uplink signal is expected to reach the network device may also be understood as the network device Or the time when the first time unit estimated by the terminal is expected to arrive at the network device, the first time unit is a time unit that actually transmits the first uplink signal.

In some possible implementation manners, the time offset is a deviation between a sampling point at a time when the first uplink signal actually reaches the network device and a sampling point at a time when the first uplink signal is expected to reach the network device.

In the embodiment of the present application, the time unit may be a radio frame, a sub-frame, a time slot, a mini-slot, an OFDM symbol defined in an LTE or 5G NR system, or may be composed of multiple radio frames or sub-frames Time window, such as the SI window.

The clock synchronization method in the embodiment of the present application sends a time offset to the terminal through the network device, which helps meet the high-precision clock synchronization requirement between the network device and the terminal.

With reference to the second aspect, in some possible implementation manners of the second aspect, the network device sending the first indication information to the terminal includes: at a second time unit, the network device sends the first indication information to the terminal Wherein the second time unit is the Nth time unit after the first time unit; or the second time unit is the Nth available time unit after the first time unit; or the second time The unit is the first available time unit after the Nth time unit, the first time unit is a time unit that actually transmits the first uplink signal, and N is a positive integer greater than or equal to 1.

In some possible implementation manners, the network device sends the first indication information in a first time window after receiving the first uplink signal.

In some possible implementation manners, a time length, an appearance period, and a time offset with respect to the first uplink signal of the first time window are configured by the network device or predefined by a protocol.

With reference to the second aspect, in some possible implementation manners of the second aspect, the network device sends the first indication information to the terminal, including: when the time deviation is greater than or equal to a first time threshold, the network device sends the first indication information to the terminal. The terminal sends the first indication information.

With reference to the second aspect, in some possible implementation manners of the second aspect, the first indication information further includes information used to indicate time-frequency resources of the first uplink signal; or, the first indication information further includes information for Information indicating frequency domain resources of the first uplink signal; or, the first instruction information further includes information used to indicate time domain resources of the first uplink signal.

The method for clock synchronization in the embodiment of the present application helps the terminal to determine the time in the first indication information by carrying information about time domain resources and / or frequency domain resources of the first uplink signal in the first indication information. The deviation is obtained by the terminal sending a first uplink signal.

With reference to the second aspect, in some possible implementation manners of the second aspect, the method further includes: the network device sends second instruction information to the terminal, where the second instruction information includes a granularity used to indicate a granularity of the time deviation. information.

In some possible implementation manners, the first indication information and the second indication information are carried in the same signaling.

In some possible implementation manners, the granularity of the time deviation is a positive integer number of nanoseconds (ns) or 2 ^μT _C or T _S.

In some possible implementation manners, the granularity of the time deviation is 100 ns, 50 ns, 10 ns, or 2 ^μT _C or T _S.

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

According to a third aspect, a clock synchronization apparatus is provided, and the apparatus includes a unit for performing the foregoing steps in the first aspect or any possible implementation manner of the first aspect.

According to a fourth aspect, a clock synchronization apparatus is provided, and the apparatus includes a unit for performing each step in the second aspect or any possible implementation manner of the second aspect.

According to a fifth aspect, a clock synchronization apparatus is provided. The apparatus includes at least one processor and a memory, where the at least one processor is configured to execute the foregoing first aspect or a method in any possible implementation manner of the first aspect.

According to a sixth aspect, an apparatus for clock synchronization is provided. The apparatus includes at least one processor and a memory, and the at least one processor is configured to execute the second aspect or the method in any possible implementation manner of the second aspect.

According to a seventh aspect, a clock synchronization device is provided. The device includes at least one processor and an interface circuit, and the at least one processor is configured to execute the foregoing first aspect or the method in any possible implementation manner of the first aspect.

According to an eighth aspect, an apparatus for clock synchronization is provided. The apparatus includes at least one processor and an interface circuit, and the at least one processor is configured to execute the method in the second aspect or any possible implementation manner of the second aspect.

In a ninth aspect, a terminal is provided. The terminal includes the device provided in the third aspect, or the terminal includes the device provided in the fifth aspect, or the terminal includes the device provided in the seventh aspect.

According to a tenth aspect, a network device is provided. The network device includes the device provided in the fourth aspect, or the network device includes the device provided in the sixth aspect, or the network device includes the device provided in the eighth aspect. .

According to an eleventh aspect, a computer program product is provided. The computer program product includes a computer program that, when executed by a processor, is used to execute the first aspect or a method in any possible implementation manner of the first aspect. , Or the method in the second aspect or any possible implementation of the second aspect.

According to a twelfth aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores a computer program, and when the computer program is executed, it is used to execute the first aspect or any possible implementation manner of the first aspect. Method, or the method in the second aspect or any possible implementation of the second aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a communication system according to an embodiment of the present application.

FIG. 2 is a schematic diagram of a network architecture provided by an embodiment of the present application.

FIG. 3 is another schematic diagram of a network architecture provided by an embodiment of the present application.

FIG. 4 is a schematic diagram of high-precision clock synchronization provided by an embodiment of the present application.

FIG. 5 is a schematic flowchart of a clock synchronization method according to an embodiment of the present application.

FIG. 6 is a schematic block diagram of a clock synchronization apparatus according to an embodiment of the present application.

FIG. 7 is another schematic block diagram of a clock synchronization apparatus according to an embodiment of the present application.

FIG. 8 is a schematic structural diagram of a terminal according to an embodiment of the present application.

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

detailed description

The following describes some terms in this application:

1) Terminal, also known as user equipment (UE), mobile station (MS), mobile terminal (MT), etc., is a device that provides voice / data connectivity to users , For example, handheld devices with wireless connectivity, in-vehicle devices, etc. At present, some examples of terminals are: mobile phones, tablet computers, laptops, handheld computers, mobile internet devices (MID), wearable devices, virtual reality (VR) devices, and augmented reality (augmented reality) equipment, wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical surgery, and smart grids Wireless terminals, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, and the like.

2) The network device is a device in a wireless network, for example, a radio access network (RAN) node that connects a terminal to the wireless network. At present, some examples of RAN nodes are: base station, next-generation base station gNB, transmission and reception point (TRP), evolved Node B (eNB), home base station, and baseband unit (BBU). , Or an access point (AP) in a WiFi system. In a network structure, the network device may be a centralized unit (CU) node, a distributed unit (DU) node, or a RAN device including a CU node and a DU node.

The technical solutions in the embodiments of the present application can be applied to various communication systems, such as: a long term evolution (LTE) system, an LTE frequency division duplex (FDD) system, and an LTE time division duplex (LTE time division duplex). (TDD), global interconnected microwave access (worldwide microwave access, WiMAX) communication system, 5th generation (5G) mobile communication system, or new wireless (NR).

FIG. 1 is a schematic diagram of a communication system 100 according to an embodiment of the present application. As shown in FIG. 1, a terminal 110 and a terminal 120 access a wireless network to obtain services of an external network (such as the Internet) through the wireless network, or The wireless network communicates with other terminals. The wireless network includes a RAN 130, where the RAN 130 is used to access the terminal 110 and the terminal 120 to a wireless network.

It should be understood that the data transmission method provided in this application may be applicable to a wireless communication system, for example, the wireless communication system 100 shown in FIG. 1. There is a wireless communication connection between two communication devices in a wireless communication system. One of the two communication devices may correspond to the terminal 110 shown in FIG. 1. For example, the communication device may be the terminal 110 shown in FIG. 1. It may be a chip configured in the terminal 110; the other communication device of the two communication devices may correspond to the RAN 130 shown in FIG. 1, for example, it may be the RAN 130 in FIG. 1, or it may be the RAN 130 configured in the RAN 130 chip.

It should also be understood that the communication system 100 shown in FIG. 1 may further include a core network (CN), and the CN may be used to manage a terminal and provide a gateway for communication with an external network.

In the embodiment of the present application, high-precision clock synchronization is a process in which a terminal corrects a current clock deviation according to signal transmission time information between the RAN 130 and the terminal. The basic principle is to assume the reciprocity of the uplink and downlink propagation delays, and use the time information of the signal transmission to solve the clock deviation, and finally achieve the purpose of high-precision clock synchronization.

The network architecture described in the embodiments of the present application is to facilitate the reader to clearly understand the technical solutions in the embodiments of the present application, and does not constitute a limitation on the technical solutions provided in the embodiments of the present application. Those of ordinary skill in the art may know that as the network architecture evolves With the emergence of new service scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

FIG. 2 is a schematic diagram of a network architecture provided by an embodiment of the present application. As shown in FIG. 2, the network architecture includes a CN device and a RAN device. The RAN device includes a baseband device and a radio frequency device. The baseband device can be implemented by one node or multiple nodes. The radio frequency device can be implemented independently from the baseband device, or it can be integrated with the baseband device in the same physical device. , Or part of the remote part is integrated with the baseband device. For example, in an LTE communication system, an eNB as a RAN device includes a baseband device and a radio frequency device. The radio frequency device can be remotely arranged relative to the baseband device, such as a remote radio unit (RRU) remotely arranged relative to the BBU. .

The communication between the RAN device and the terminal follows a certain protocol layer structure. For example, the control plane protocol layer structure may include a radio resource control (RRC) layer, a packet data convergence layer protocol (PDCP) layer, a radio link control (RLC) layer, and a media interface. Functions of the protocol layer such as the access control (MAC) layer and the physical layer. The user plane protocol layer structure may include the functions of the protocol layers such as the PDCP layer, the RLC layer, the MAC layer, and the physical layer; in one implementation, the PDCP layer may also include a service data adaptation (SDAP) layer .

A RAN device can implement the functions of the protocol layers such as radio resource control, packet data convergence layer protocol, radio link control, and media access control by one node; or the functions of these protocol layers can be implemented by multiple nodes; for example, in a In this evolved structure, a RAN device may include a CU and a DU, and multiple DUs may be centrally controlled by a CU. As shown in Figure 2, CU and DU can be divided according to the protocol layer of the wireless network. For example, the functions of the PDCP layer and above are set in the CU, and the functions of the protocol layers below PDCP, such as the RLC layer and the MAC layer are set in the DU.

This division of the protocol layer is only an example. It can also be divided at other protocol layers, for example, at the RLC layer. The functions of the RLC layer and above are set in the CU, and the functions of the protocol layers below the RLC layer are set in the DU. Alternatively, it is divided in a certain protocol layer, for example, setting some functions of the RLC layer and functions of the protocol layer above the RLC layer in the CU, and setting the remaining functions of the RLC layer and the functions of the protocol layer below the RLC layer in the DU. In addition, it can also be divided in other ways, such as by delay, and the functions that need to meet the delay requirements in processing time are set in the DU, and the functions that do not need to meet the delay requirements are set in the CU.

In addition, the radio frequency device can be remote, not placed in the DU, or integrated in the DU, or part of the remote can be integrated in the DU, without any restrictions here.

Please continue to refer to FIG. 3. FIG. 3 shows a schematic diagram of another network architecture provided by an embodiment of the present application. Compared with the architecture shown in FIG. 2, the control plane (CP) and user plane (UP) of the CU can also be changed. It is separated and implemented by different entities, which are a control plane CU entity (CU-CP entity) and a user plane CU entity (CU-UP entity).

In the above network architecture, the signaling generated by the CU can be sent to the terminal through the DU, or the signaling generated by the terminal can be sent to the CU after being received through the DU. The DU can directly transmit to the terminal or the CU through protocol layer encapsulation without parsing the signaling. In the above embodiments, the CU is divided into network equipment on the RAN side. In addition, the CU may also be divided into network equipment on the CN side, which is not limited herein.

The devices in the following embodiments of the present application may be located in a terminal or a network device according to the functions they implement. When the above CU-DU structure is adopted, the network device may be a CU node, or a DU node, or a network device including a CU node and a DU node.

In the embodiments of the present application, the architecture of the CU and DU is not limited to 5G, NR, and gNB, and can also be applied to a scenario where an LTE base station is divided into CU and DU. Optionally, when it is an LTE base station, the protocol layer does not include an SDAP layer.

The following illustrates the principle of high-precision clock synchronization through a simple diagram.

In wireless communication systems, network equipment and terminals have their own clock systems. The clock system performs timing according to a predefined rule; the time rule can be a time system defined by an international standard, or a time standard defined by a local area network. The network device can calibrate its own clock system through a wired network or a global positioning system (GPS); the terminal can calibrate the terminal's clock system through the time synchronization process using the network device's clock system as a reference.

It is assumed that the time information of the network equipment is represented by t ^BS , and the time information of the terminal is represented by t ^UE , and it is assumed that t ^UE = t ^BS + T _offset , that is, the time information displayed by the clock system of the network equipment and the terminal exists at the same time T. _offset time offset. The purpose of high-precision clock synchronization is to estimate and eliminate the time offset T _offset between the network device and the clock system of the terminal. The high-precision clock synchronization process requires that the network device and the terminal each send a signal to each other. For the timing signal, the network device sends a downlink timing signal to the terminal, and the terminal sends the network device an uplink timing signal.

向终端发送下行授时信号，终端在

收到该下行授时信号，且终端在

向网络设备发送上行授时信号，网络设备在

收到该上行授时信号。假设上下行授时信号的传播时延分别为P _UL和P _DL。 Figure 4 shows a schematic diagram of high-precision clock synchronization. As shown in Figure 4, it is assumed that the network device

Send a downlink timing signal to the terminal.

Received the downlink timing signal, and the terminal is at

Send an uplink timing signal to the network device. The network device is in

Receive the uplink timing signal. Assume that the propagation delays of the uplink and downlink timing signals are P _UL and P _{DL, respectively} .

Based on the above assumptions, the following two equations (1) and (2) can be listed. In general, if the transmission time interval of the uplink and downlink timing signals is not too long, and the terminal is not in a very high-speed motion scene, it can be assumed that the uplink and downlink propagation delays are the same, that is, P _UL = P _DL . In this way, T _offset can be solved by the following equations, and the terminal can also appropriately adjust the local clock according to the T _offset value to maintain high-precision clock synchronization.

P _UL = P _DL (3)

From the above equations (1), (2) and (3):

和

)，可以得到网络设备和终端的时钟系统之间的时间偏差T _offset。 It can be seen that the network device and the terminal interact with the timing signal to determine the time information corresponding to the sending and receiving of the uplink and downlink timing signals on the network device or the terminal's clock system (for example, in Figure 4).

with

), The time offset T _offset between the network device and the clock system of the terminal can be obtained.

和

分别是终端侧的接收信号、发送信号对应的时刻在该终端的时钟系统上的时间信息，可以依靠终端的时钟系统获得，其精度取决于终端实现。

with

The time information on the terminal's clock system at the time corresponding to the received and transmitted signals on the terminal side can be obtained by the terminal's clock system, and its accuracy depends on the terminal implementation.

为网络设备发送下行授时信号的无线帧的边界对应的时刻在该网络设备的时钟系统上的时间信息。终端可以通过网络设备发送的资源调度信息以及之前得到的高精度授时信息得到该时间信息，因此，

对于终端也是已知的。由于下行信号要按照第三代合作伙伴计划(3rd generation partnership project，3GPP)空口的帧结构进行发送，所以理想情况下每个帧边界间隔为10毫秒(millisecond，ms)。终端可以根据NR或者LTE系统中的系统信息(如，SIB16)或者专用的新设计的高精度时间通知消息，计算下行授时信号的帧边界对应的时刻在网络设备的时钟系统上的时间信息

即公式(5)所示：

Time information on the clock system of the network device for the time corresponding to the boundary of the wireless frame that sends the downlink timing signal for the network device. The terminal can obtain the time information through the resource scheduling information sent by the network device and the high-precision timing information obtained before. Therefore,

It is also known to the terminal. Since the downlink signal is to be transmitted according to the frame structure of the 3rd generation partnership project (3GPP) air interface, ideally, each frame boundary interval is 10 milliseconds (ms). The terminal can calculate the time information on the clock system of the network device at the time corresponding to the frame boundary of the downlink timing signal according to the system information in the NR or LTE system (such as SIB16) or a dedicated new design high-precision time notification message

That is, as shown in formula (5):

表示承载系统信息(如，SIB16)或者专用的新设计的高精度时间通知消息 的参考帧边界对应的时刻在该网络设备的时钟系统上的时间信息，T _frame表示无线帧长度，例如，T _frame等于10ms，m表示下行授时信号对应的帧边界相对于参考帧边界的帧偏移量，m为大于或者等于0的整数。 among them,

Represents time information on the clock system of the network device at the time corresponding to the reference frame boundary of the bearer system information (eg, SIB16) or a dedicated newly designed high-precision time notification message. T _frame represents the length of the wireless frame, for example, T _frame It is equal to 10ms, m represents the frame offset of the frame boundary corresponding to the downlink timing signal from the reference frame boundary, and m is an integer greater than or equal to 0.

就是参考帧边界对应的时刻在该网络设备的时钟系统上的时间信息。 In particular, when m = 0,

It is the time information on the clock system of the network device at the moment corresponding to the frame boundary.

It should be understood that the time unit boundary of the timing signal in the following line in formula (5) is taken as an example to illustrate the wireless frame boundary. The time unit boundary may also be a subframe boundary, a slot boundary, a microslot boundary, or an orthogonal frequency division complex Orthogonal frequency division multiplexing (OFDM) symbol boundaries. Correspondingly, T _frame can be replaced with a sub-frame length, a slot length, a mini-slot length, or an OFDM symbol length.

For example, the time unit boundary of the downlink timing signal may be a time slot boundary, as shown in formula (6):

表示参考点对应的时刻，该下行授时信号对应的时隙边界相对于参考点对应的时刻的偏移量为m个无线帧和k个时隙，k为大于或者等于0的整数。 Where T _slot is the slot length,

Represents the time corresponding to the reference point. The offset of the time slot boundary corresponding to the downlink timing signal from the time corresponding to the reference point is m radio frames and k time slots, and k is an integer greater than or equal to zero.

As another example, the time unit boundary of the downlink timing signal may be a symbol boundary, as shown in formula (7):

T _symbol is the symbol length, and the offset of the symbol boundary corresponding to the downlink timing signal from the time corresponding to the reference point is m radio frames, k slots, and l symbols, where l is an integer greater than or equal to 0 .

是网络设备接收到终端发送的上行授时信号对应的时刻在该网络设备的时钟系统上的时间信息，终端并不知道该时间信息，因此需要网络设备向终端指示该时间信息。

It is the time information on the clock system of the network device when the network device receives the uplink timing signal sent by the terminal. The terminal does not know the time information, so the network device needs to indicate the time information to the terminal.

的时间信息，其它时间信息对于终端都是已知的。 In summary, the terminal needs to obtain

Time information, other time information is known to the terminal.

是网络设备收到上行授时信号对应的理想时刻(帧边界)在该网络设备的时钟系统上的时间信息。终端可以通过网络设备发送的资源调度信息以及之前得到的高精度时间通知消息得到，因此

对于终端也是已知的，网络设备的调度信息指示了

与

的帧/时隙偏移量，即公式(8)所示：

It is the time information on the clock system of the network device at the ideal time (frame boundary) corresponding to the network device receiving the uplink timing signal. The terminal can be obtained through the resource scheduling information sent by the network device and the high-precision time notification message obtained previously, so

Also known to the terminal, the scheduling information of the network device indicates

versus

Frame / slot offset, as shown in formula (8):

Wherein, n represents the frame offset of the frame boundary corresponding to the uplink timing signal received by the network device relative to the reference frame boundary.

计算方式也不限于公式(8)，还可以有其他的计算方式，为了简洁，这里不加赘述。 It should be understood that, similar to the foregoing formulas (6) and (7), in the embodiment of the present application

The calculation method is not limited to the formula (8), and there may be other calculation methods. For the sake of brevity, we will not repeat them here.

或者

来间接得到

Therefore, the terminal can also get

or

Come indirectly

或者

In order to maintain high-precision time synchronization with network equipment, for example, the synchronization error needs to be within ± 500 nanoseconds (nanosecond, ns), the terminal needs to periodically adjust the clock to overcome the crystal oscillator drift. In other words, it is necessary to periodically send the uplink and downlink timing signals and obtain the clock offset T _offset . The network device can send the timing signals to the terminal in time after receiving the timing signals.

or

和

可以在第一指示信息中指示，该第一指示信息为网络设备检测到上行授时信号的实际时刻和理想时刻的时间偏差。 For convenience of description, in the embodiments of the present application,

with

It may be indicated in the first instruction information, where the first instruction information is a time deviation between the actual time and the ideal time when the network device detects the uplink timing signal.

It should be understood that, in the embodiments of the present application, the clock system of the network device may work in accordance with a coordinated universal time (UTC) clock or a global navigation satellite system (GNSS) clock; the UTC clock uses The UTC time system identifies time (or records time information). The GNSS clock uses the GNSS time system to identify time. The 3GPP clock is a time representation method defined by the wireless communication system based on the LTE / 5GNR frame structure.

FIG. 5 shows a schematic flowchart of a clock synchronization method 200 according to an embodiment of the present application. As shown in FIG. 5, the execution body of the method 200 may be a clock synchronization device (for example, a terminal or a chip for a terminal or Device, network device or chip or device for network device), the following description is made with the execution subject as the terminal and the network device. The method 200 includes:

S210: The terminal sends a first uplink signal to a network device, and the network device receives the first uplink signal sent by the terminal.

Optionally, the first uplink signal includes, but is not limited to, a sounding reference signal (SRS), a modulation reference signal (DMRS), a phase tracking reference signal (PTRS), a physical Random access channel (physical random access channel, PRACH) or a newly designed dedicated reference signal.

It should be understood that the first uplink signal may correspond to the uplink timing signal in FIG. 4.

Optionally, before S210, the method further includes:

S201. The network device sends a downlink signal to the terminal, and the terminal receives the downlink signal sent by the network device.

Optionally, the downlink signal includes, but is not limited to, a physical downlink control channel (PDCCH), a DMRS on a physical downlink shared channel (PDSCH), and a channel state information reference signal (channel state information) -reference signal (CSI-RS), tracking reference signal (CSI-RS for tracking / TRS), synchronization signal block (SSB), primary synchronization signal (PSS), secondary synchronization signal (secondary) synchronization (SSS), DMRS or PTRS.

It should be understood that the downlink signal may correspond to the downlink timing signal in FIG. 4.

It should also be understood that the terminal receives the downlink signal sent by the network device in the downlink time unit.

S220. The network device sends the first instruction information to the terminal. The terminal receives the first instruction information sent by the network device. The first instruction information is used to indicate that the time when the first uplink signal actually reaches the network device and the first The time deviation of the time when an upstream signal is expected to reach the network device.

It should be understood that the time when the first uplink signal is expected to reach the network device may also be understood as the target arrival time of the first uplink signal, or the time when the first uplink signal is expected to reach the network device may also be understood as the network device Or the time when the boundary of the first time unit calculated by the terminal is expected to reach the network device.

It should also be understood that the boundary of the first time unit may be a start boundary or an end boundary of the first time unit.

In this embodiment of the present application, the time unit may be a radio frame, a sub-frame, a time slot, a mini-slot, an OFDM symbol, or multiple frames or sub-frames defined in an LTE or 5G NR system. Time window, such as the system information (SI) window.

)，确定第一指示信息，该第一指示信息用于指示该第一上行信号实际到达该网络设备的时刻与该第一上行信号预期到达该网络设备的时间偏差。 Specifically, after the network device receives the first uplink signal sent by the terminal, according to the actual receiving time of the first uplink signal (for example, FIG. 4

) To determine first indication information, where the first indication information is used to indicate a time difference between the time when the first uplink signal actually arrives at the network device and the time when the first uplink signal is expected to arrive at the network device.

)之间的时间偏差(例如，

)。 Optionally, the first indication information may indicate a time when the first uplink signal actually arrives at the network device and a time when the first time unit estimated by the network device or terminal arrives at the network device (for example, in FIG. 4

) (For example,

).

It should be understood that Δt is a time deviation under a clock system of a network device, for example, it may be a time deviation under a UTC or GNSS clock system.

Optionally, the time deviation is a deviation between a sampling point at which the first uplink signal actually reaches the network device and a sampling point at which the first uplink signal is expected to reach the network device (for example, the time deviation may be expressed as N _diff ).

It should be understood that N _diff is the time deviation under the 3GPP air interface frame timing time system. The reason for N _diff is the change in signal transmission time P _UL and P _DL , or N _diff represents the error of the adjustment amount of TA, which can be understood as The correction of the TA adjustment amount makes the TA notification accuracy higher. It should also be understood that Δt includes N _diff and also includes the time deviation that occurs during the interval between the downlink signal reception and the first uplink signal transmission. The time deviation is determined by the clock system of the network equipment and the 3GPP air interface frame timing time system. The difference between the timing frequency is generated. If the hardware of the network equipment is ideal enough, this deviation is on the order of ns, so Δt and N _diff can be considered approximately the same.

Optionally, the sending, by the network device, the first indication information to the terminal includes:

The network device uses the first cycle to send the first instruction information to the terminal.

Optionally, the first period is a period in which the terminal sends an uplink signal.

Specifically, the first uplink signal sent by the terminal in S210 may correspond to the first indication information determined by the network device in S220, so the sending mechanism of the first indication information may be a mechanism that follows the clock synchronization process. It is determined that the first indication information may be sent periodically or aperiodically.

For example, when the clock synchronization process is aperiodic and temporarily configured (for example, when the terminal starts time synchronization, it can initiate an aperiodic clock synchronization process and then transition to periodic synchronization), then the first indication information is sent It can also be aperiodic.

As another example, when the clock synchronization process is performed periodically, the sending of the first indication information is also cyclic, and the periods of the two may be the same.

In the method for clock synchronization in the embodiment of the present application, a network device periodically sends a time offset to a terminal, and the terminal can obtain the time offset periodically, thereby performing clock synchronization, which helps to meet the high-precision Clock synchronization requirements.

Optionally, the network device sending the first instruction information to the terminal includes: at a second time unit, the network device sends the first instruction information to the terminal, and the terminal receives the first instruction information sent by the network device Wherein the second time unit is the Nth time unit after the first time unit; or the second time unit is the Nth available time unit after the first time unit; or the second time The unit is the first available time unit after the Nth time unit, and N is a positive integer greater than or equal to 1.

For example, if N is 2, the time unit is a time slot, and the second time unit is the Nth time unit after the first time unit, the network device receives the first uplink signal in the first time slot Then, the first indication information may be sent to the terminal in a third time slot.

Optionally, at the first time resource location of the second time unit, the network device sends the first indication information to the terminal.

For example, the first time resource location may be some symbols in the third time slot.

Optionally, N is configured by a network device, or N is predefined by a protocol.

Optionally, the network device sends the first indication information in a first time window after receiving the first uplink signal.

Optionally, a time length, an appearance period, and a time offset with respect to the first uplink signal of the first time window are configured by the network device or predefined by a protocol.

Optionally, the first indication information may be carried in downlink control information (DCI), medium access control element (MAC CE), or radio resource control (RRC). Signaling.

It should be understood that considering the real-time nature of the first indication information and the flexibility of information transmission, an optional solution is that the first indication information is carried in the MAC CE.

Optionally, the method further includes: the network device sends second instruction information to the terminal, the terminal receives the second instruction information sent by the network device, and the second instruction information includes a granularity for indicating a granularity of the time deviation. information.

It should be understood that the second indication information includes information used to indicate the granularity of the time deviation, and it can also be understood that the second indication information includes a field, which is used to indicate the granularity of the time deviation.

Optionally, the granularity of the time deviation is a positive integer ns or 2 ^μ T _C or T _s , where 2 ^μ is a magnification of the system sampling period, T _C is the minimum sampling time period defined in NR, and μ is positive The integer and the size of μ can be determined by the subcarrier interval and the communication system bandwidth. T _s is a basic time unit defined by LTE, and T _s is equal to 1 / (15000 × 2048) seconds.

Optionally, the granularity of the time deviation is 100 ns, 50 ns, 10 ns, and 2 ^μT _C or T _s .

Optionally, the time deviation (Δt or N _diff ) and the granularity of the time deviation may be carried in the same signaling. For example, both the time deviation and the time deviation are carried in the MAC CE; the time deviation and the time deviation also have the same granularity. It can be carried in different signaling, for example, the time deviation is indicated in the MAC CE, and the granularity of the time deviation is carried in the RRC signaling.

In a possible implementation manner, in the initial stage of high-precision time synchronization, the network device indicates the granularity of time deviation through RRC signaling, and after the network device receives the uplink signal, it sends the first indication information using MAC CE. .

Optionally, the granularity of the time deviation is implicitly determined by the terminal and the network device through known parameters.

For example, the terminal and the network device determine the granularity of the corresponding time deviation through the accuracy requirements of time synchronization or parameters such as the uplink signal bandwidth.

In the method for clock synchronization in the embodiment of the present application, the terminal can obtain a fine-grained time offset, which is helpful to meet the accuracy of clock synchronization.

Optionally, the first indication information further includes information of a type of the time offset.

For example, the network device may add an identifier to the first indication information, and the identifier is used to distinguish Δt and N _diff .

Optionally, the first indication information further includes information used to indicate time-frequency resources of the first uplink signal; or, the first indication information further includes information used to indicate frequency domain resources of the first uplink signal; or The first indication information further includes information used to indicate time domain resources of the first uplink signal.

The information of the time domain resource may be an identifier of the time domain resource, the information of the frequency domain resource may be an identifier of the frequency domain resource, and the information of the time frequency resource may be an identifier of the time frequency resource.

When the terminal sends multiple uplink signals to the network device, and the multiple uplink signals include the first uplink signal, the network device may add time domain resources and / or frequency domains of the first uplink signal to the first indication information. Resource information, so that the terminal determines that the time deviation in the first indication information is obtained by sending the first uplink signal from the terminal.

Optionally, the triggering manner of the first indication information may be an uplink signal trigger or a condition trigger.

Method 1 (uplink signal trigger)

If the triggering method of the first indication information is an uplink signal trigger, the network device sends the first indication information to the terminal within a certain period of time after receiving the first uplink signal.

Method two (conditional trigger)

If the triggering method of the first indication information is conditional trigger, after determining the time deviation, the network device determines whether the time deviation is greater than or equal to the first time threshold. If the time deviation is greater than or equal to the first time threshold, the The network device sends the first indication information to the terminal; if the time deviation is less than the first time threshold, the network device does not send the first indication information.

For example, if the time deviation Δt is 50 ns and the first time threshold is 100 ns, the network device does not send the first instruction information to the terminal.

It should be understood that the network device may also determine whether the time deviation is greater than a first time threshold after determining the time deviation, and if the time deviation is greater than the first time threshold, the network device sends the first instruction information to the terminal; If the time deviation is less than or equal to the first time threshold, the network device does not send the first indication information.

Optionally, the first time threshold is determined by factors such as accuracy of time synchronization or hardware implementation of the network device, and may be determined by the network device, or implicitly determined by the terminal and the network device through known parameters.

For example, the terminal and the network device may determine the first time threshold according to the bandwidth of the uplink signal; since the larger the uplink channel bandwidth, the more accurate the detection result of the system, the first time threshold may also be reduced accordingly.

For another example, the terminal and the network device may also determine the first time threshold according to different synchronization accuracy requirements.

S230. The terminal performs clock synchronization according to the time deviation.

Specifically, the terminal corrects the local clock after receiving the first instruction information.

For example, when the time deviation is the time deviation Δt under the clock system of the network device, the time correction method is as shown in formula (9), and the time deviation between the clock of the network device and the terminal is calculated:

As another example, when the time deviation is the time deviation N _diff under the 3GPP air interface frame timing time system, the time correction method is as shown in formula (10):

表示终端估算的下行时间单元边界对应的时刻在该网络设备的时钟系统上的时间信息，N _TA为该网络设备通知该终端发送第一上行信号的提前量，用于补偿下行信道和上行信道的传播时延的总和。该终端根据

和该终端本地时钟显示的时刻

的差异完成时间同步，即通过

确定T _offset，该终端在确定T _offset后，通过T _offset来修正该终端的时钟显示的时刻

或者，终端在估算得到

后，直接将

写入该终端的时钟。 among them,

Represents the time information on the clock system of the network device at the time corresponding to the downlink time unit boundary estimated by the terminal. N _{TA is} the amount of advance for the network device to notify the terminal to send the first uplink signal and is used to compensate Sum of propagation delays. The terminal is based on

And the time displayed by the terminal's local clock

Complete the time synchronization by passing

T _offset is determined, after determining that the terminal T _offset, corrected by the terminal T _offset time clock display

Or, the terminal is getting

Directly

Write the clock to this terminal.

It should be understood that the time deviation Δt under the clock system of the network device and the time deviation N _diff under the 3GPP air interface frame timing time system can be converted to each other.

It should also be understood that the same dimension should be used when calculating the time deviation. If the first instruction information indicates that the granularity of the time deviation is 2 ^μT _C , then the terminal should convert N _diff to Granularity in seconds.

It should also be understood that the terminal monitors the first indication information for a period of time after the first uplink signal is sent. If the first indication information is received, then according to Δt or N _diff and the time synchronization formula (9) or (10) ) Perform clock correction; if no corresponding information is received, it is considered that Δt or N _diff is 0 and no correction is performed.

Optionally, the method further includes: adjusting, by the terminal, a sending advance of the second uplink signal according to the time offset.

The second uplink signal may be a next uplink signal to be sent after the terminal sends the first uplink signal.

When the sending and receiving antenna parameter configurations of the first uplink signal and the second uplink signal are the same or the channel-related characteristics are satisfied, the time offset may be used to adjust the sending advance of the second uplink signal.

Specifically, if the first instruction information indicates N _diff , the terminal may further adjust the transmission advance of the second uplink signal according to the time offset, and the terminal may adjust the transmission advance of the second uplink signal. It is (N _TA + N _diff ) × T _S.

The clock synchronization method according to the embodiment of the present application has been described in detail above with reference to FIGS. 1 to 5, and the apparatus, terminal, and network device for clock synchronization in the embodiment of the present application are described in detail below with reference to FIGS. 6 to 9.

An embodiment of the present application further provides an apparatus for implementing any one of the foregoing methods. For example, an apparatus is provided, which includes a unit (or means) for implementing each step performed by a terminal in any one of the above methods. For another example, another apparatus is provided, which includes a unit (or means) for implementing each step performed by a network device in any one of the methods.

FIG. 6 shows a schematic block diagram of a clock synchronization apparatus 300 according to an embodiment of the present application. The apparatus 300 may correspond to the terminal described in the foregoing method 200, and may also correspond to a chip or component of the terminal. The modules or units may be respectively used to perform various actions or processing processes performed by the terminal in the foregoing method 200. As shown in FIG. 6, the clock synchronization apparatus 300 may include a processing unit 310, a sending unit 320, and a receiving unit 330.

Specifically, the processing unit 310 is configured to generate a first uplink signal;

The sending unit 320 is configured to send a first uplink signal to a network device.

The receiving unit 330 is configured to receive first instruction information from the network device, where the first instruction information is used to indicate a time when the first uplink signal actually arrives at the network device and a time when the first uplink signal is expected to arrive at the network device. Time deviation

The processing unit 310 is further configured to perform clock synchronization according to the time deviation.

It should be understood that, for a specific process of each unit in the device 300 performing the foregoing corresponding steps, please refer to the description of the method embodiment in conjunction with FIG. 5 in the foregoing, and for the sake of brevity, details are not described herein.

It should also be understood that if the clock synchronization device 300 is a chip in a terminal, a processing unit in the chip may generate a clock synchronization instruction according to the first instruction information, and send the clock synchronization instruction to the clock synchronization unit of the terminal for clock synchronization.

FIG. 7 shows a schematic block diagram of a clock synchronization apparatus 400 according to an embodiment of the present application. The apparatus 400 may correspond to the network device described in the foregoing method 200, and may also correspond to a chip or component of the network device. Furthermore, the apparatus 400 Each module or unit in the method may be used to perform each action or processing performed by the network device in the foregoing method 200. As shown in FIG. 7, the clock synchronization apparatus 400 may include a receiving unit 410, a processing unit 420, and a sending unit 430. .

Specifically, the receiving unit 410 is configured to receive a first uplink signal from a terminal;

The processing unit 420 is configured to control the sending unit 430 to send the first instruction information to the terminal, where the first instruction information is used to indicate a time when the first uplink signal actually reaches the network device and a time when the first uplink signal is expected to reach the network device Time deviation of time, this time deviation is used by the terminal for clock synchronization.

It should be understood that, for a specific process in which each unit in the apparatus 400 executes the foregoing corresponding steps, please refer to the description of the method embodiment in conjunction with FIG. 5 in the foregoing. For brevity, details are not described herein.

It should also be understood that the division of the units in the above device is only a division of logical functions. In actual implementation, it may be fully or partially integrated into a physical entity, or it may be physically separated. And all units in the device can be implemented by software through the processing element call; all units can also be implemented by hardware; some units can also be implemented by software via the processing element call, and some units can be implemented by hardware. For example, each unit can be a separately established processing element, or it can be integrated into a chip of the device to achieve it. In addition, it can also be stored in the form of a program in the memory and called and executed by a certain processing element of the device. Features. The processing element described here can also be called a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above units may be implemented by an integrated logic circuit of hardware in a processor element or in a form called by software through a processing element.

In one example, the unit in any of the above devices may be one or more integrated circuits configured to implement the above method, for example: one or more application specific integrated circuits (ASICs), or, one or Multiple digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs), or a combination of at least two of these integrated circuit forms. As another example, when a unit in the device can be implemented in the form of a processing element scheduler, the processing element may be a general-purpose processor, such as a central processing unit (CPU) or another processor that can call a program. As another example, these units can be integrated together and implemented in the form of a system-on-a-chip (SOC).

FIG. 8 is a schematic structural diagram of a terminal according to an embodiment of the present application. It may be the terminal in the above embodiments, and is used to implement the operation of the terminal in the above embodiments. As shown in FIG. 8, the terminal includes: an antenna 510, a radio frequency device 520, and a signal processing section 530. The antenna 510 is connected to the radio frequency device 520. In the downlink direction, the radio frequency device 520 receives the information sent by the network device through the antenna 510, and sends the information sent by the network device to the signal processing section 530 for processing. In the uplink direction, the signal processing section 530 processes the information of the terminal and sends it to the radio frequency device 520. The radio frequency device 520 processes the information of the terminal and sends it to the network device via the antenna 510.

The signal processing section 530 may include a modulation and demodulation subsystem to implement processing of each communication protocol layer of the data; it may also include a central processing subsystem to implement processing of the terminal operating system and the application layer; in addition, it may also include Other subsystems, such as multimedia subsystems and peripheral subsystems. Among them, the multimedia subsystem is used to control the terminal camera and screen display, and the peripheral subsystem is used to achieve connection with other devices. The modem subsystem can be an independent chip. Optionally, the above device for a terminal may be located in the modulation and demodulation subsystem.

The modem subsystem may include one or more processing elements 531, for example, including a main control CPU and other integrated circuits. In addition, the modem subsystem may further include a storage element 532 and an interface circuit 533. The storage element 532 is used to store data and programs, but the program used to execute the method executed by the terminal in the above method may not be stored in the storage element 532 but stored in a memory other than the modem subsystem. The interface circuit 533 is used to communicate with other subsystems. The above device for a terminal may be located in a modulation and demodulation subsystem, which may be implemented by a chip. The chip includes at least one processing element and an interface circuit, and the processing element is configured to perform any method performed by the terminal. Each step of the interface circuit is used to communicate with other devices. In one implementation, the unit that the terminal implements each step in the above method may be implemented in the form of a processing element scheduler. For example, a device for a terminal includes a processing element and a storage element, and the processing element calls a program stored by the storage element to execute the above The method executed by the terminal in the method embodiment. The storage element may be a storage element whose processing element is on the same chip, that is, an on-chip storage element.

In another implementation, the program for executing the method executed by the terminal in the above method may be a storage element on a different chip from the processing element, that is, an off-chip storage element. At this time, the processing element calls or loads the program from the off-chip storage element to the on-chip storage element to call and execute the method executed by the terminal in the foregoing method embodiments.

In another implementation, the unit that implements each step in the above method of the terminal may be configured as one or more processing elements, and these processing elements are provided on the modulation and demodulation subsystem. The processing elements here may be integrated circuits, such as : One or more ASICs, or, one or more DSPs, or, one or more FPGAs, or a combination of these types of integrated circuits. These integrated circuits can be integrated together to form a chip.

The unit that implements each step in the above method in the terminal may be integrated together and implemented in the form of a system-on-a-chip (SOC). The SOC chip is used to implement the above method.

FIG. 9 is a schematic structural diagram of a network device according to an embodiment of the present application. It is used to implement the operation of the network device in the above embodiments. As shown in FIG. 9, the network device includes an antenna 601, a radio frequency device 602, and a baseband device 603. The antenna 601 is connected to the radio frequency device 602. In the uplink direction, the radio frequency device 602 receives the information sent by the terminal through the antenna 601, and sends the information sent by the terminal to the baseband device 603 for processing. In the downlink direction, the baseband device 603 processes the information of the terminal and sends it to the radio frequency device 602. The radio frequency device 602 processes the information of the terminal and sends it to the terminal via the antenna 601.

The baseband device 603 may include one or more processing elements 6031, for example, including a main control CPU and other integrated circuits. In addition, the baseband device 603 may further include a storage element 6032 and an interface 6033. The storage element 6032 is used to store programs and data; the interface 6033 is used to exchange information with the radio frequency device 602. The interface is, for example, a common public wireless interface , CPRI). The above device for a network device may be located in a baseband device 603. For example, the above device for a network device may be a chip on the baseband device 603. The chip includes at least one processing element and an interface circuit, and the processing element is used to execute the above network. The device executes each step of any method, and the interface circuit is used to communicate with other devices. In one implementation, the unit that the network device implements each step in the above method may be implemented in the form of a processing element scheduler. For example, an apparatus for a network device includes a processing element and a storage element. The processing element calls a program stored by the storage element, The method performed by the network device in the foregoing method embodiment is performed. The storage element may be a storage element on the same chip as the processing element, that is, an on-chip storage element, or a storage element on a different chip from the processing element, that is, an off-chip storage element.

In another implementation, the unit that the network device implements each step in the above method may be configured as one or more processing elements, which are disposed on the baseband device. The processing element here may be an integrated circuit, for example: an Or multiple ASICs, or one or more DSPs, or one or more FPGAs, or a combination of these types of integrated circuits. These integrated circuits can be integrated together to form a chip.

A unit that implements each step in the above method by a network device may be integrated together and implemented in the form of a system on a chip. For example, the baseband device includes the SOC chip to implement the above method.

The terminal and the network device in each of the foregoing device embodiments may completely correspond to the terminal or the network device in the method embodiment, and corresponding modules or units execute corresponding steps. For example, when the device is implemented in a chip manner, the receiving The unit may be an interface circuit that the chip uses to receive signals from other chips or devices. The above sending unit is an interface circuit of the device for sending signals to other devices. For example, when the device is implemented as a chip, the sending unit is the chip for sending signals to other chips or devices. Interface circuit.

An embodiment of the present application further provides a communication system. The communication system includes the foregoing terminal and the foregoing network device.

It can be understood that the memory in the embodiment of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), or Erase programmable read-only memory (EPROM, EEPROM) or flash memory. The volatile memory may be random access memory (RAM), which is used as an external cache. There are many different types of RAM, such as static random access memory (static RAM, SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (synchronous DRAM, SDRAM), double data rate Synchronous dynamic random access memory (double SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronously connected dynamic random access memory (synchlink DRAM, SLDRAM), and direct memory bus random access Fetch memory (direct RAMbus RAM, DR RAM).

It should be understood that, in the various embodiments of the present application, the size of the sequence numbers of the above processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not deal with the embodiments of the present application. The implementation process constitutes any limitation.

In addition, the terms "system" and "network" are often used interchangeably herein. The term "and / or" in this document is only a kind of association relationship describing related objects, which means that there can be three kinds of relationships, for example, A and / or B can mean: A exists alone, A and B exist simultaneously, and exists alone B these three cases. In addition, the character "/" in this text generally indicates that the related objects are an "or" relationship.

The terms "first" and "second" appearing in this application are only for distinguishing different objects, and "first" and "second" themselves do not limit the actual order or function of the objects they modify. Any embodiment or design described as "exemplary", "example", "for example", "optional design", or "one design" in this application should not be interpreted as being inferior to other embodiments or The design scheme is more preferred or more advantageous. Rather, these words are used to present related concepts in a concrete way.

The terms "uplink" and "downlink" appearing in this application are used to describe the direction of data / information transmission in specific scenarios. For example, the direction of "uplink" generally refers to the direction or distribution of data / information from the terminal to the network side. The direction in which the unit transmits to the centralized unit. The "downlink" direction generally refers to the direction in which data / information is transmitted from the network side to the terminal, or the direction in which the centralized unit transmits to the distributed unit. It can be understood that "uplink" and "downlink" "" It is only used to describe the direction of data / information transmission, and the specific start and stop of the data / information transmission are not limited.

Various objects such as various messages / information / devices / network elements / systems / devices / actions / operations / processes / concepts may be assigned names in this application. It is understandable that these specific names are not It constitutes a restriction on the related object. The name given can be changed according to the scene, context, or usage habits. The understanding of the technical meaning of the technical terms in this application should mainly be based on the functions they reflect / execute in the technical solution. And technical effects to determine.

In the foregoing embodiments, all or part of the implementation may be implemented by software, hardware, firmware, or any combination thereof. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product may include one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions according to the embodiments of the present application are wholly or partially generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be from a website site, a computer, a server, or a data center. Transmission to another website site, computer, server, or data center via wired (such as coaxial cable, optical fiber, digital subscriber (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, a data center, or the like that includes one or more available medium integration. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic disk), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)), or the like.

Those of ordinary skill in the art may realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. A professional technician can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

The above is only a specific implementation of this application, but the scope of protection of this application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in this application. It should be covered by the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims (19)

A method for clock synchronization, comprising: Sending a first uplink signal to a network device; Receiving first instruction information from the network device, where the first instruction information is used to indicate a time when the first uplink signal actually reaches the network device and a time when the first uplink signal is expected to reach the network device Time deviation of time According to the time deviation, clock synchronization is performed. The method according to claim 1, wherein the receiving the first indication information from the network device comprises: In a second time unit, receiving the first instruction information from the network device; The second time unit is the Nth time unit after the first time unit, or the second time unit is the Nth available time unit after the first time unit, or the first The two time units are the first available time units after the Nth time unit, the first time unit is a time unit for transmitting the first uplink signal, and N is a positive integer greater than or equal to 1. The method according to claim 1 or 2, further comprising: Adjusting the transmission advance of the second uplink signal according to the time deviation. The method according to any one of claims 1-3, wherein the first indication information further comprises information used to indicate time-frequency resources of the first uplink signal; or, the first indication The information further includes information used to indicate a frequency domain resource of the first uplink signal; or, the first indication information further includes information used to indicate a time domain resource of the first uplink signal. The method according to any one of claims 1-4, further comprising: Receiving second instruction information from the network device, where the second instruction information includes information used to indicate a granularity of the time deviation. The method according to any one of claims 1-5, wherein the first indication information is carried in downlink control information DCI, a media access control layer control element MAC CE, or radio resource control RRC signaling. A method for clock synchronization, comprising: Receiving a first uplink signal from a terminal; Sending first indication information to the terminal, the first indication information being used to indicate a time when the first uplink signal actually arrives at the network device and a time when the first uplink signal is expected to arrive at the network device Offset, the time offset is used by the terminal for clock synchronization. The method according to claim 7, wherein the sending the first indication information to the terminal comprises: Sending the first indication information to the terminal in a second time unit; The second time unit is the Nth time unit after the first time unit, or the second time unit is the Nth available time unit after the first time unit, or The second time unit is a first available time unit after the Nth time unit, the first time unit is a time unit for transmitting the first uplink signal, and N is a positive integer greater than or equal to 1. The method according to claim 7 or 8, wherein the sending the first indication information to the terminal comprises: Sending the first indication information to the terminal when the time deviation is greater than or equal to a first time threshold. The method according to any one of claims 7 to 9, wherein the first indication information further comprises information for indicating time-frequency resources of the first uplink signal; or, the first indication The information further includes information used to indicate a frequency domain resource of the first uplink signal; or, the first indication information further includes information used to indicate a time domain resource of the first uplink signal. The method according to any one of claims 7 to 10, wherein the method further comprises: Send second instruction information to the terminal, where the second instruction information includes information used to indicate a granularity of the time deviation. The method according to any one of claims 7 to 11, wherein the first indication information is carried in downlink control information DCI, a media access control layer control element MAC CE, or radio resource control RRC signaling. A clock synchronization device, comprising units for performing each step of the method according to any one of claims 1-6. A clock synchronization device, comprising units for performing each step of the method according to any one of claims 7-12. A clock synchronization device, comprising at least one processor and an interface circuit, wherein the at least one processor is configured to execute the method according to any one of claims 1-6. A clock synchronization device, comprising at least one processor and an interface circuit, wherein the at least one processor is configured to execute the method according to any one of claims 7-12. A terminal, comprising the device according to claim 13 or 15. A base station, comprising the apparatus according to claim 14 or 16. A storage medium, comprising a program, and when the program is executed by a processor, the method according to any one of claims 1-12 is executed.

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