CN111756464A

CN111756464A - Time synchronization method and device

Info

Publication number: CN111756464A
Application number: CN201910253496.6A
Authority: CN
Inventors: 吴霁; 张佳胤; 贾琼
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-03-29
Filing date: 2019-03-29
Publication date: 2020-10-09

Abstract

The application relates to the technical field of communication, and discloses a time synchronization method and a time synchronization device, which are used for solving the problem of inaccurate time synchronization between a terminal and network equipment. The method comprises the following steps: a terminal receives synchronization information sent by network equipment, wherein indication information in the synchronization information is used for indicating a time domain position of the network equipment for actually sending the synchronization information; and the terminal determines the time domain position for actually receiving the synchronous information according to the indication information. Therefore, accurate synchronous time is obtained according to the determined time domain position, and time synchronization is realized.

Description

Time synchronization method and device

Technical Field

The embodiment of the application relates to the technical field of communication, in particular to a time synchronization method and device.

Background

In order to meet the communication demand, the terminal needs to perform time synchronization with the network device. A synchronization signal burst set (SS burst set) is defined in the New Radio (NR). The SSburst set includes a number of synchronization signal/physical broadcast channel blocks (SS/PBCH blocks). In this application, the SS/PBCH block is referred to as a Synchronization Signal Block (SSB). The terminal and the network device may be time synchronized by an SS/PBCH block or a Discovery Reference Signal (DRS), and the network device may transmit one or more consecutive SS/PBCH blocks or DRSs to the terminal at a time. The SS/PBCH block may help the UE identify and synchronize with the cell, including the most basic system information such as radio frame number, intra-frame timing information, etc. The terminal successfully receives the SS/PBCH block is a precondition for accessing the cell. A DRS includes an SS/PBCH block and system information associated with the SS/PBCH block, such as Remaining Minimal System Information (RMSI), etc.

In addition, at a specific subcarrier spacing (SCS), the time domain position in the SS burst set window where the SS/PBCH block (serial number 0) is preset to start transmitting is also defined in the NR standard. The preset initial sending time domain position corresponding to the SS/PBCHlock is indicated by a time index (time index) in the PBCH. When the terminal detects an SS/PBCH block, the terminal may determine which preset time domain position to start sending corresponds to the SS/PBCH block in the SS burst set window according to a time index (time index) carried by a PBCH in the SS/PBCH block, and further determine symbols (i.e., PSS symbols and SSs symbols in the SS/PBCH block) occupied by system timing information in the SS burst set window. In addition, the terminal may determine, according to the half frame indication information (half frame indication) carried by the PBCH in the SS/PBCH block, whether the SS burst set window in which the SS/PBCH block is located in the first 5ms or the last 5ms of a 10ms radio frame (radio frame). Therefore, the terminal can correctly receive the system timing information sent by the network equipment (such as the gNB)), and the time synchronization between the terminal and the network equipment is completed.

However, due to the influence of Listen Before Talk (LBT) mechanism, for an NR (NR unsupported, NRU) system operating in an unlicensed frequency band, a network device may not be able to send an SS/PBCH block at a time domain location where the SS/PBCH block is preset to be sent, and when system information related to the SS/PBCH block is sent along with the SS/PBCH block, that is, when the network device sends a DRS for time synchronization, the network device may also be unable to send the DRS at a time domain location where the SS/PBCH block is preset to be sent initially. If the terminal still considers that the network device sends the SS/PBCH block or DRS at the preset time domain location, a time synchronization error between the terminal and the network device may be caused, and therefore, a solution is urgently needed to solve the problem of time synchronization between the terminal and the network device in the NRU system.

Disclosure of Invention

The embodiment of the application provides a time synchronization method and a time synchronization device, which are used for solving the problem that time synchronization between a terminal and network equipment is inaccurate.

In a first aspect, a method for time synchronization is provided, where a network device may send a synchronization information group to a terminal, where the synchronization information group includes one or more pieces of synchronization information that are continuously sent, that is, the network device sends one or more pieces of synchronization information to the terminal, the terminal receives any piece of synchronization information sent by the network device, the synchronization information received by the terminal includes indication information, where the indication information is used to indicate a first time domain position at which the network device actually sends the synchronization information, and after receiving the synchronization information, the terminal may determine, according to the indication information, the first time domain position at which the network device actually sends the synchronization information, where the first time domain position at which the network device actually sends the synchronization information is also a time domain position at which the terminal actually receives the synchronization information.

The network equipment sends indication information used for indicating an actual sending position to the terminal, and the terminal can determine a first time domain position of the synchronization information actually sent by the network equipment through the indication information, so that accurate synchronization time is obtained according to the first time domain position, and time synchronization is realized.

In one possible implementation, the synchronization information sent by the network device to the terminal includes, but is not limited to: DRS or SSB.

In a possible implementation, the indication information directly indicates a time domain position at which the network device actually sends the time synchronization information, that is, the indication information includes a first time domain position at which the network device actually sends the time synchronization information, and the terminal determines the first time domain position in the indication information as the time domain position at which the synchronization information is actually received.

In a possible implementation, the indication information may be used to indicate a first offset between a first time domain position at which the network device actually sends the synchronization information and a second time domain position at which the network device presets to start sending a synchronization information group to which the synchronization information belongs. After receiving the synchronization information, the terminal may first determine, according to the indication information in the synchronization information, a first offset between a first time domain position at which the network device actually sends the synchronization information and a second time domain position at which the network device presets to start sending a synchronization information group to which the synchronization information belongs, and then determine, according to the determined offset and the second time domain position at which the network device presets to start sending the synchronization information group to which the synchronization information belongs, the first time domain position at which the network device actually sends the synchronization information, that is, the time domain position at which the terminal actually receives the synchronization information. The second time domain position of the synchronization information group to which the network device presets to start sending the synchronization information may be carried in the indication information or may be prestored by the terminal according to a protocol specification.

The network equipment sends indication information for indicating the first offset to the terminal, and the terminal can determine the first offset through the indication information and determine the first time domain position of the synchronization information actually sent by the network equipment through the first offset, so that accurate synchronization time is obtained according to the first time domain position, and time synchronization is realized.

In a possible implementation, the network device may directly indicate, through the indication information, a first offset between a first time domain position at which the network device actually sends the synchronization information and a second time domain position at which the network device presets to start sending a synchronization information group to which the synchronization information belongs, and then the indication information may include the first offset between the first time domain position at which the network device actually sends the synchronization information and the second time domain position at which the network device presets to start sending the synchronization information group to which the synchronization information belongs, and the terminal may directly obtain the first offset through the indication information.

In a possible implementation, the network device may indirectly indicate, through the indication information, a first offset between a first time domain position at which the network device actually sends the synchronization information and a second time domain position at which the network device presets to start sending a synchronization information group to which the synchronization information belongs, where the indication information may include a second offset between a third time domain position at which the network device actually starts sending the synchronization information group to which the synchronization information belongs and a second time domain position at which the network device presets to start sending the synchronization information group to which the synchronization information belongs, and a third offset between a fourth time domain position at which the network device presets sending the synchronization information and a second time domain position at which the network device presets to start sending the synchronization information group to which the synchronization information belongs. The second offset combined with the third offset may be considered the first offset. The terminal may obtain the second offset and the third offset through the indication information, and combine the second offset and the third offset together to obtain the first offset, and if the offset is a numerical value, it may be understood that the sum of the numerical value corresponding to the second offset and the numerical value corresponding to the third offset is the numerical value corresponding to the first offset.

In a possible implementation, the network device may indirectly indicate, through indication information, a first offset between a first time domain position at which the network device actually sends the synchronization information and a second time domain position at which the network device presets to start sending a synchronization information group to which the synchronization information belongs, where the indication information may include: the number of the synchronous information in the synchronous information group to which the synchronous information sent by the network equipment belongs, the offset coefficient of the synchronous information sent by the network equipment, and the serial number of the synchronous information sent by the network equipment. The offset coefficient is a multiple of a second offset between a third time domain position of a synchronization information group to which the synchronization information belongs, which is actually sent by the network equipment at the beginning, and a first time domain position of a synchronization information group to which the synchronization information belongs, which is preset by the network equipment at the beginning, and a number of time domains occupied by the synchronization information group to which the synchronization information belongs. The multiple is generally an integer multiple, generally 0-4. What the network device sends is what the terminal receives. The terminal may calculate, according to the information included in the indication information, a first offset between a first time domain position at which the network device actually sends the synchronization information and a second time domain position at which the network device presets to start sending a synchronization information group to which the synchronization information belongs. If the time domain location comprises: the slot number. The terminal may calculate, according to the content included in the indication information, a first offset between a first time domain position at which the network device actually sends the synchronization information and a second time domain position at which the network device presets to start sending a synchronization information group to which the synchronization information belongs, where the first offset may be understood as a number of time slots that are offset, and if a synchronization information offset coefficient d in the indication information is 0, calculate the first offset according to n ═ a × b, and if the synchronization information offset coefficient in the indication information is not 0, determine the first offset according to n ═ a + d × e × a, where n is a number of time slots at which the network device actually sends the synchronization information (first time domain position) that are offset from a time slot at which the network device presets to start sending the synchronization information group to which the synchronization information belongs (second time domain position), a is a numerical value of a slot occupied by the synchronization information, b is a serial number of the synchronization information, b is an integer equal to or greater than 0, d is an integer of which the synchronization information offset coefficient d is greater than or equal to 0, and e is the number of the received synchronization information in a synchronization information group to which the synchronization information belongs. When the number n of time slots in which the time slot (first time domain position) of the network device actually sending the synchronization information is offset relative to the time slot (second time domain position) of the synchronization information group to which the network device presets to start sending the synchronization information is determined, the determined n can be added to the time slot number c of the synchronization information group to which the network device presets to start sending the synchronization information, and then the time slot number of actually receiving the synchronization information can be obtained. I.e. can be according to the formula: m ═ a × b + c + d × e × a, and a slot number for actually receiving the synchronization information is determined; wherein m is a time slot number for actually receiving the synchronization information, and c is a time slot number (second time domain position) for presetting a synchronization information group to which the synchronization information belongs to be initially sent.

In a possible implementation, the slot occupied by the synchronization information may be pre-stored, or may be included in the indication information, and the terminal may obtain the slot occupied by the received synchronization information according to the slot occupied by the pre-stored synchronization information, that is, the terminal uses the slot occupied by the pre-stored synchronization information as the slot occupied by the synchronization information received by the terminal; or the terminal acquires the received slot occupied by the synchronous information according to the slot occupied by the synchronous information included in the indication information, namely the terminal takes the slot occupied by the synchronous information included in the indication information as the acquired slot occupied by the synchronous information received by the terminal.

In a possible implementation, the timeslot number of the synchronization information group to which the initial transmission of the synchronization information belongs is preset to be pre-stored or included in the indication information. The terminal can acquire the time slot number of the synchronization information group to which the received synchronization information belongs according to the pre-stored time slot number of the preset initial sending synchronization information group, that is, the terminal takes the pre-stored time slot number of the preset initial sending synchronization information group as the acquired time slot number of the synchronization information group to which the synchronization information belongs; or the terminal acquires the received time slot number of the synchronization information group to which the synchronization information belongs according to the time slot number of the preset initial sending synchronization information group included in the indication information, that is, the terminal takes the time slot number of the preset initial sending synchronization information group included in the indication information as the acquired time slot number of the synchronization information group to which the synchronization information belongs received by the terminal.

In one possible implementation, when the network device transmits the synchronization information group, the synchronization information group may be transmitted across a radio frame, that is, the actually transmitted time domain position of the previous part of the synchronization information in the synchronization information group is in a previous radio frame, and the actually transmitted time domain position of the next part of the synchronization information in the synchronization information group is in a next radio frame, and the previous radio frame is adjacent to the next radio frame. The time slot number calculated according to the formula in the possible implementation is larger than the maximum value of the time slot number included in the wireless frame, and in order to further determine the time slot number for actually receiving the synchronization information accurately, after the terminal determines the time slot number for actually receiving the synchronization information by adopting the formula, the maximum value of the time slot number included in the wireless frame radio frame at the current subcarrier interval can be obtained; and determining whether the number of the time slot actually receiving the synchronization information is greater than the maximum value; and if the difference value is larger than the maximum value, calculating the difference value between the number of the time slot actually receiving the synchronous information and the maximum value, and taking the difference value as the number of the time slot actually receiving the synchronous information.

In a second aspect, there is provided an apparatus for time synchronization having functional modules for implementing the method in any one of the possible implementations of the above aspects and aspects. The functional modules can be realized by hardware, and can also be realized by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above-described functions.

In one possible implementation, the apparatus may be a chip or an integrated circuit.

In one possible implementation, the apparatus includes a transceiver and a processor, and the apparatus may perform the method in any one of the possible implementations of the first to fourth aspects and the various aspects through the processor.

The transceiver may be an interface circuit.

In one possible implementation, the apparatus may further include a memory; the memory is used for storing the computer program.

In a third aspect, a computer-readable storage medium is provided having computer-readable instructions stored therein that, when executed, cause an apparatus to perform the method of the above aspects and any possible implementation of the aspects.

In a fourth aspect, a computer program product is provided that, when executed, enables an apparatus to perform the method of the above aspects and any possible implementation of the aspects.

In a fifth aspect, a chip is provided, the chip being coupled with a memory, the chip being configured to read and execute a software program stored in the memory to implement the above aspects and the method in any possible implementation of the aspects.

Drawings

Fig. 1 is a schematic structural diagram of an SS burst set provided in an embodiment of the present application;

fig. 2 is a schematic diagram of a wireless communication system according to an embodiment of the present application;

fig. 3 and fig. 4 are schematic diagrams of a Type a/Type B multi-carrier LBT mechanism provided in an embodiment of the present application;

fig. 5 is a time domain resource mapping pattern of an SS/PBCH block provided in an embodiment of the present application;

fig. 6 is a schematic diagram of a time synchronization process provided in an embodiment of the present application;

fig. 7 is a schematic diagram illustrating a transmission manner of a DRS according to an embodiment of the present application;

fig. 8 is a schematic diagram illustrating a transmission manner of a DRS according to an embodiment of the present application;

fig. 9 is a schematic diagram illustrating a transmission manner of a DRS according to an embodiment of the present application;

fig. 10 is a schematic diagram illustrating a transmission manner of a DRS according to an embodiment of the present application;

fig. 11 is a schematic diagram of a time synchronization apparatus according to an embodiment of the present application;

fig. 12 is a schematic diagram of a time synchronization apparatus according to an embodiment of the present application.

Detailed Description

The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

The embodiment of the application provides a time synchronization method and a time synchronization device, which are used for solving the problem of inaccurate time synchronization between a terminal and network equipment in the prior art. The method, the device and the system are based on the same technical conception, and because the principles of solving the problems of the method, the device and the system are similar, the implementation of the device, the system and the method can be mutually referred, and repeated parts are not repeated.

The technical scheme of the embodiment of the application can be applied to various communication systems, for example: wideband Code Division Multiple Access (WCDMA) mobile communication systems, evolved universal terrestrial radio access network (E-UTRAN) systems, Long Term Evolution (LTE) systems, future fifth Generation (5th Generation, 5G) systems, such as new radio access technology (NR), and future communication systems, such as 6G systems.

To facilitate understanding of the embodiment of the present application, a schematic structural diagram of an SS burst set is introduced next, where a New Radio (NR) defines a synchronization signal burst set SS burst set, and the SS burst set is mainly used for a terminal (including a User Equipment (UE)) to perform initial access/system message update/beam (beam) management. The transmission period of the SS burst set may be 5/10/20/40/80/100 ms. The duration of the SS burst set is related to the number of actually transmitted SS/pbcblock and the subcarrier spacing. But in either configuration the duration of the SS burst set is less than the duration of the SSburst set window by 5 ms. Fig. 1 shows one possible structure of an SS burst set, which comprises several SS/PBCH blocks. The SS/PBCH block is a signal structure. When the carrier frequency is less than 6GHz, each SS burst set contains 8 SS/PBCH blocks at most; when the carrier frequency is more than 6GHz, each SS burst contains 64 SS/PBCH blocks at most. Each SS/PBCH block may correspond to a beam in a different direction. In this application, the SS/PBCH block is referred to as a synchronization signal block SSB, although the SS/PBCH block may have other names. The Synchronization Signal block may generally include a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). In the example of fig. 1, each SSB lasts 4 Orthogonal Frequency Division Multiplexing (OFDM) symbols. The PSS and SSS mainly serve to help the UE identify and synchronize with the cell, and the PBCH contains the most basic system information such as radio frame number, intra-frame timing information, etc. The successful reception of the synchronization signal block by the terminal is a prerequisite for its access to the cell. In addition, it should be noted that one radio frame includes a plurality of slots, and one slot includes a plurality of OFDM symbols.

To facilitate understanding of the embodiments of the present application, an application scenario of the present application is described next, and referring to fig. 2, fig. 2 shows a wireless communication system 100 related to the present application. The wireless communication system 100 may operate in a licensed frequency band and may also operate in an unlicensed frequency band. It will be appreciated that the use of unlicensed frequency bands may increase the system capacity of the wireless communication system 100. As shown in fig. 2, the wireless communication system 100 includes: one or more network devices (Base Station)101, such as a gNB, eNodeB, or WLAN access point, one or more terminals (Terminal)103, and a core network 115. Wherein:

the network device 101 may be used to communicate with the terminal 103 under the control of a network device controller, such as a base station controller (not shown). In some embodiments, the network device controller may be part of the core network 115 or may be integrated into the network device 101.

The network device 101 may be configured to transmit control information (control information) or user data (user data) to the core network 115 via a backhaul (e.g., S1 interface) 113.

Network device 101 may communicate wirelessly with terminal 103 through one or more antennas. Each network device 101 may provide communication coverage for a respective coverage area 107. The coverage area 107 corresponding to the access point may be divided into a plurality of sectors (sectors), wherein one sector corresponds to a portion of the coverage area (not shown).

The network device 101 and the network device 101 may also communicate with each other directly or indirectly through a backhaul (black haul) link 211. Here, the backhaul link 111 may be a wired communication connection or a wireless communication connection.

In some embodiments of the present application, network device 101 may include: a base transceiver Station (base transceiver Station), a wireless transceiver, a Basic Service Set (BSS), an Extended Service Set (ESS), NodeB, eNodeB, gNB, and so on. The wireless communication system 100 may include several different types of network devices 101, such as macro base stations (macro base stations), micro base stations (micro base stations), and so on. Network device 101 may apply different radio technologies, such as a cell radio access technology, or a WLAN radio access technology.

The terminals 103 may be distributed throughout the wireless communication system 100 and may be stationary or mobile. In some embodiments of the present application, the terminal 103 may include: mobile devices, mobile stations (mobile stations), mobile units (mobile units), wireless units, remote units, user agents, mobile clients, and the like. In the present application, a terminal may also be understood as a terminal device.

In this application, the wireless communication system 100 may be an LTE communication system capable of operating in an unlicensed frequency band, such as an LTE-U system, a new air interface communication system capable of operating in an unlicensed frequency band, such as an NRU system, or another communication system capable of operating in an unlicensed frequency band in the future.

Additionally, the wireless communication system 100 may also include a WiFi network.

In order to ensure coexistence with other devices operating in unlicensed frequency bands, the NRU system employs the channel contention access mechanism of LBT, and the procedures and parameters of LBT are specified in release R13 of 3 GPP. Fig. 3 and 4 show two types of LBT listening mechanisms.

As shown in fig. 3, a type a (type a) LBT device may perform independent backoff on multiple Component Carriers (CCs), and delay transmission to wait for other component carriers still in backoff after backoff on a certain carrier is completed. When all carriers performing LBT complete backoff, the device needs to make an additional one-shot CCA (25 user channel assignment) to ensure that all carriers are idle; if all carriers are idle, the eNB transmits simultaneously on the idle carrier.

As shown in fig. 4, the type b (type b) LBT device performs backoff only on a certain selected component carrier, performs one-shot CCA (25us clear channel assessment) review on other component carriers when backoff is finished, and performs data transmission if the component carrier is idle; if the component carrier is not idle, the component carrier cannot be transmitted with data at this time.

As shown in fig. 3 and 4, the LBT device may be LTE LAA, WiFi, NRU or other communication devices operating in unlicensed (unlicensed) frequency band. In the figure, interference received by the device performing LBT comes from a WiFi system, and in an actual scenario, the interference received by the device performing LBT may also come from LTE LAA, NRU or other communication systems operating in an unlicensed frequency band, which is not limited in this application.

Without being limited to fig. 3 and 4, the LBT listening mechanism adopted by the NRU system may also be changed without affecting the implementation of the present application.

As shown in fig. 5, a time domain resource mapping pattern (pattern) of SS/PBCH block has been defined in NR system operating in licensed frequency band. The pattern indicates the temporal location in the SS burst set window where the SS/PBCH block may appear. Here, a series of time domain locations where SS/PBCH block may occur may be referred to as candidate SS/PBCH blocks.

Specifically, for a field carrying the SS/PBCH block (the duration of the field is an SS burst setup window), the number of candidate SS/PBCH blocks (SS/PBCH block candidates) and the index of the start symbol of the candidate SS/PBCH block are determined by the sub-carrier spacing (SCS) of the SS/PBCH block as follows:

1. SCS 15KHz, the index of the starting symbol of the candidate SS/PBCH block comprises: {2, 8} +14 × n. When the carrier frequency is less than 3GHz, n is 0, 1; when the carrier frequency is greater than 3GHz and less than 6GHz, n is 0, 1, 2, 3;

2. SCS 30KHz, the index of the starting symbol of the candidate SS/PBCH block comprises: {4, 8, 16, 20} +28 × n. When the carrier frequency is less than 3GHz, n is 0; when the carrier frequency is greater than 3GHz and less than 6GHz, n is 0, 1;

3. SCS 30KHz, the index of the starting symbol of the candidate SS/PBCH block comprises: {2, 8} +14 × n. When the carrier frequency is less than 3GHz, n is 0, 1; when the carrier frequency is greater than 3GHz and less than 6GHz, n is 0, 1, 2, 3;

4. SCS 120KHz, the index of the starting symbol of the candidate SS/PBCH block comprises: {4, 8, 16, 20} +28 × n. When the carrier frequency is greater than 6GHz, n is 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18;

5. SCS 240KHz, the index of the starting symbol of the candidate SS/PBCH block comprises: {8, 12, 16, 20, 32, 36, 40, 44} +56 × n. When the carrier frequency is greater than 6GHz, n is 0, 1, 2, 3, 5, 6, 7, 8.

Wherein the candidate SS/PBCH blocks in the SS burst set window are numbered from 0 to L-1 in a time ascending sequence; l is a positive integer, which may have a value equal to 4 or greater than 4 (but not greater than 64). These numbers are also known as time indices (timeindex).

It can be seen that for a particular SCS (e.g., SCS 15KHz), the time domain position in the SS burst set window for the default transmitted SS/PBCH block (i.e., the candidate SS/PBCH block) has been specified in the NR.

In the NR system, when a terminal detects a SS/PBCH block, the terminal may determine which preset initial time domain position corresponds to the SS/PBCH block in the SS burst set window according to a time index (time index) carried by a PBCH in the SS/PBCH block, and further determine a symbol (i.e., a PSS symbol and a SSs symbol in the SS/PBCH block) occupied by system timing information in the SS burst set window. In addition, the terminal may determine, according to the half frame indication information (half frame indication) carried by the PBCH in the SS/PBCH block, whether the SS burst set window in which the SS/PBCH block is located in the first 5ms or the last 5ms of a 10ms radio frame (radio frame). Therefore, the terminal can correctly receive the system timing information sent by the network equipment (such as the gNB), and the time synchronization between the terminal and the network equipment is completed.

However, due to the influence of the Listen Before Talk (LBT) mechanism, for an NR (NR unlicenced, NRU) system operating in an unlicensed frequency band, a network device may not be able to transmit an SS/PBCH block at a time domain position where the SS/PBCH block is scheduled to be transmitted initially.

The SS/PBCH block related system information includes, but is not limited to, remaining minimum system information RMSI, Other System Information (OSI), paging message paging. When the system information related to the SS/PBCH block is transmitted together with the SS/PBCH block, that is, when the network device transmits the DRS for time synchronization, the SSB occupies 4 consecutive OFDM symbols in the time domain, the DRS may occupy 7 symbols, 14 symbols, 21 symbols, 28 symbols in the time domain according to the difference including information, generally occupies an integer multiple of 7 symbols, and a target includes 14 symbols in 1 complete slot. The DRS occupies different symbols in the time domain according to the difference including the included information, which may also result in that the network device cannot transmit the DRS at the time domain position where the SS/PBCH block is scheduled to be transmitted.

If the terminal still considers that the network device sends the SS/PBCH block or DRS at the preset time domain position, a time synchronization error between the terminal and the network device may be caused. Based on this, as shown in fig. 6, the present application provides a method for time synchronization between a terminal and a network device, where the network device informs the terminal of an offset of a time domain position, and the terminal can determine, according to the offset, a time domain position where the network device actually sends synchronization information, that is, a time domain position where the terminal actually receives the synchronization information, thereby accurately achieving time synchronization.

Step 61: the method comprises the steps that the network equipment sends synchronous information to the terminal, and then the terminal receives the synchronous information sent by the network equipment, wherein the synchronous information comprises indication information which is used for indicating a first time domain position of the network equipment for actually sending the synchronous information.

Step 62: and the terminal determines the time domain position for actually receiving the synchronous information according to the indication information.

In a possible implementation, the network device may carry, in the indication information, the first time domain position where the network device actually sends the synchronization information, and the terminal may directly obtain, according to the indication information, the first time domain position where the network device actually sends the synchronization information, that is, the time domain position where the terminal actually receives the synchronization information.

And step 63: and the terminal acquires the synchronization time according to the time domain position actually receiving the synchronization information and achieves time synchronization with the network equipment according to the synchronization time.

In the present application, a network device sends synchronization information to a terminal, and the terminal performs time synchronization with the network device through the synchronization information, where the synchronization information includes, but is not limited to, DRS and SSB. The DRS may also be referred to as a DRS unit, DRS block, and the synchronization information may also be referred to as a synchronization information unit. When the network device sends the synchronization information to the terminal, one or more of the synchronization information may be sent, and the synchronization information group may include one or more synchronization information sent continuously.

In this application, the network device may configure a time domain position for sending the synchronization information group, and the configured time domain position for sending the synchronization information group is referred to as a time domain position for presetting a start sending synchronization information group, where the time domain position for presetting the start sending synchronization information group may start from a start of a radio frame, may start from a half frame of the radio frame, and may certainly start from other time domain positions of the radio frame. If the configured time domain position of the preset initial sending synchronization information group is one, the time domain position of the preset initial sending synchronization information group can be stored in the terminal in advance; if the configured time domain positions of the preset initial sending synchronization information group are multiple, the network device may notify the terminal, and when the network device sends the synchronization information group, the time domain position of the preset initial sending synchronization information group is which, specifically, the network device may carry the time domain position of the preset initial sending synchronization information group in the indication information, and the terminal may obtain, from the indication information, the time slot number of the synchronization information group to which the preset initial sending received synchronization information belongs. Of course, the network device may also send the time domain position of the preset initial sending synchronization information group to the terminal through other messages.

The network equipment sends one or a plurality of continuous synchronous information to the terminal, before sending any synchronous information, the network equipment can generate indicating information for indicating a first time domain position for actually sending the synchronous information and a first offset between a second time domain position for presetting a synchronous information group to which the synchronous information belongs to be sent initially, and carries the indicating information in the synchronous information and sends the indicating information to the terminal. The terminal can receive synchronization information sent by network equipment, the synchronization information comprises indication information, the terminal obtains a first offset between a first time domain position used for indicating the network equipment to actually send the synchronization information and a second time domain position of a synchronization information group to which the network equipment presets to start sending the synchronization information according to the indication information, and then determines a time domain position for actually receiving the synchronization information according to the obtained first offset and the second time domain position of the synchronization information group to which the network equipment presets to start sending the synchronization information.

For example, the network device may directly inform the terminal of the first offset through the indication information.

The network device may determine a first offset between a first time domain position at which the synchronization information is actually sent and a second time domain position at which a synchronization information group to which the synchronization information belongs is preset to be initially sent, and send the first offset to the terminal by being carried in the indication information, that is, the indication information includes the first offset.

When the terminal determines the time domain position of actually receiving the synchronization information according to the indication information and the time domain position of the synchronization information group to which the network device is preset to start sending the synchronization information, the terminal can directly acquire the first offset from the indication information, and the terminal shifts the first offset in the indication information backwards at the second time domain position of the synchronization information group to which the network device is preset to start sending the synchronization information, so that the time domain position of actually sending the synchronization information by the network device is obtained. The time domain position where the network device actually sends the synchronization information is the time domain position where the terminal actually receives the synchronization information.

For example, the network device may indirectly inform the terminal of the first offset through the indication information.

For example, the network device may indicate an offset of a synchronization information group and an offset of a single synchronization information in the synchronization information group, and specifically, the indication information may include a second offset between a third time domain position at which the network device actually starts sending the synchronization information of the synchronization information group and a second time domain position at which the network device presets starting sending the synchronization information of the synchronization information group, and a third offset between a fourth time domain position at which the network device presets sending the synchronization information and a second time domain position at which the network device presets starting sending the synchronization information of the synchronization information group. The third offset and the second offset are combined to be regarded as the first offset.

When the terminal determines the time domain position for actually receiving the synchronization information according to the indication information and the time domain position of the synchronization information group to which the network device is preset to start sending the synchronization information, the terminal may shift backward the second offset and the third offset in the indication information at the second time domain position of the synchronization information group to which the network device is preset to start sending the synchronization information, so as to obtain the time domain position for actually sending the synchronization information by the network device. The time domain position where the network device actually sends the synchronization information is the time domain position where the terminal actually receives the synchronization information.

The time domain position includes, but is not limited to, slot number in a radio frame, OFDM symbol in a slot.

The following description will take the time domain position as the timeslot number in the radio frame as an example: the offset is also in units of slots, i.e., the number of slots that are offset.

For example, if the network device presets that the slot number of the synchronization information group to which the synchronization information belongs is to be sent initially is slot0 (a second time domain position), and the indication information includes that a first offset between a first time domain position at which the network device actually sends the synchronization information and a second time domain position at which the network device presets that the synchronization information group to which the synchronization information belongs is to be sent initially is 4 slots offset, the terminal may determine the sum of the slot number 0 of the synchronization information group to which the network device presets that the synchronization information belongs and the number 4 of the slots offset as the slot number at which the synchronization information is actually received, and then the slot number at which the terminal actually receives the synchronization information is slot 4.

For example, the slot number of the synchronization information group to which the synchronization information belongs is preset to be sent at the beginning by the network device to be slot4 (a second time domain position), a second offset between a third time domain position to which the synchronization information belongs is actually sent at the beginning by the network device and a second time domain position to which the synchronization information group to which the synchronization information belongs is preset to be sent at the beginning by the network device to be offset by 8 slots, a third offset between a fourth time domain position to which the synchronization information is preset to be sent by the network device and a second time domain position to which the synchronization information group to which the synchronization information belongs is preset to be sent at the beginning by the network device to be offset by 2 slots, and then the terminal may be offset backward by 8+2 slots on slot4, and then the slot number to which the synchronization information is actually received is determined to be slot 14.

The network device may indirectly tell the terminal about the first offset through the indication information, for example, the network device may carry relevant information of the synchronization information in the indication information, for example, the indication information may include the number of synchronization information included in a synchronization information group to which the synchronization information belongs, which is received by the terminal, that is, the number of synchronization information continuously sent by the network device this time; the offset coefficient of the synchronization information received by the terminal may be included, and generally, the offset coefficient of each synchronization information in the synchronization information group is the same; the sequence number of the synchronization information received by the terminal may be included, and generally, the sequence number of each synchronization information in the synchronization information group is different.

The indication information may further include a slot occupied by the synchronization information received by the terminal, and a second time domain position of a synchronization information group to which the synchronization information belongs, which is preset by the network device to be initially sent; certainly, the slot occupied by the synchronization information and the time domain position where the network device presets to start sending the synchronization information group may also be pre-stored by the terminal, and the network device does not need to notify the terminal. The value of each slot occupied by each piece of synchronization information in the general synchronization information group is the same, and the synchronization information can occupy 1 slot, can occupy 0.5 slot, and can also occupy other slots with other values; the value of the slot occupied by the synchronization information may be understood as the duration of the synchronization information or the time length of the synchronization information. It should be noted that the synchronization information received by the terminal is also the synchronization information sent by the network device.

Referring to fig. 7 to 9, the offset coefficient in the indication information is a multiple of a second offset between a third time domain position of a synchronization information group to which the synchronization information actually starts to be sent and a second time domain position of a synchronization information group to which the synchronization information belongs, which is preset by the network device to start to be sent, and a number of time domains occupied by the synchronization information group to which the synchronization information belongs. Generally, the time is an integer multiple, which may be 0 to 4 times, and if the offset coefficient is 0, it indicates that the third time domain position of the actual start sending synchronization information group is the same as the second time domain position of the preset start sending synchronization information group.

The terminal calculates a first offset between a first time domain position of the network equipment actually sending the synchronization information and a second time domain position of a synchronization information group to which the network equipment presets to start sending the synchronization information according to the information carried in the indication information, namely the number of offset time slots.

Taking the time domain position as the time slot number as an example, a specific process that the terminal determines the time domain position actually receiving the synchronization information according to the related information of the synchronization information described above included in the indication information is described in detail as follows:

the terminal determines the number of the time slot actually receiving the synchronization information according to the following formula, the number of the time slot starts from 0, and the number of the time slot is an integer equal to or greater than 0.

m＝a*b+c+d*e*a；

Wherein m is a time slot number for actually receiving the synchronization information; a is the number of time slots occupied by the synchronous information; b is a sequence number of the synchronization information, b generally starts from 0, b is an integer not less than 0, and for example, a slot sequence number may be 0, 1, 2, etc.; c is a time slot number of a synchronization information group to which the synchronization information is preset to be initially sent, such as time slot0, time slot4, time slot8 and the like; d is the synchronization information offset coefficient, the value of d is generally an integer from 0 to x, x is a value obtained by rounding up Y/e, Y is the number of time domain positions of DRSs/SSBs with sequence number 0, which are preset and initially sent in each DRS/SSB window specified by the standard, for example, when Y is 18 and e is 4, x is 5, and the value of d is 0, 1, 2, 3, 4; e is the number of the received synchronization information in the synchronization information group to which the synchronization information belongs, and e is a positive integer greater than 1, such as 1, 3, 4, etc.

The sequence number of the synchronization information, the number of synchronization information in a synchronization information group to which the synchronization information belongs, an offset coefficient of the synchronization information, a value of a slot occupied by the synchronization information, a preset initial transmission position of the synchronization information group, and the like may be carried by a PBCH mrs sequence, a master information block (master information block MIB), a PBCH load (payload), and the like.

Taking the synchronization information as DRS as an example, in the present application, a DRS sequence number (SSB QCL indication index) may be indicated by a PBCH DMRS sequence, and a persistent symbol number (a slot occupied value) of each DRS (unit) may be indicated by MIB or PBCH payload. The number of DRSs configured in the transmission of the network device may be indicated by MIB or PBCH payload, and the offset coefficient wrap around idx of the DRS may be indicated by PBCH payload or MIB.

And the UE can obtain accurate time synchronization according to the DRS serial number, the DRS unit duration, the DRS sending number, the wrap around idx and the DRS half-frame indication information. A 1-bit (half frame indication) for indicating that DRS is located in the first/second half of a frame may multiplex a half frame indication (half frame indication) indicating that SSB is located in the first or second half of a radio frame in the original NR. Furthermore, the DRS unit duration may also be indicated in the RMSI CORESET or given directly in the standard. The PBCH DMRS may be used to indicate one or more of a DRS unit duration, a DRS transmission number, and a wrap around idx, in addition to a DRS sequence number (SSB QCL indication index). The SSB QCLindication index is QCL indication index.

Next, the principle of determining the slot number of the synchronization information actually received by the above formula is described in a specific embodiment:

one possible way to transmit synchronization information is shown in fig. 7, where the transmission position of the configured synchronization information group always starts from the beginning of a radio frame (i.e. slot0 in each radio frame). When the subcarrier spacing SCS interval is 30kHz, 20slots (20slots with in radio frame) are included in one 10ms radio frame.

In fig. 7, it is assumed that the network device is configured to continuously transmit 4 DRS units in each DRS window, which is abbreviated as DRS hereinafter, and the sequence number (SSB QCL indication) is divided into 0 to 3, that is, a DRS group transmitted by the network device includes 4 DRSs, the time length (length) of the DRS is 1 slot, and the DRS group has 3 alternative initial transmission positions (slot0, slot4, slot8, respectively) to cope with the influence of LBT. It should be noted that the alternative starting transmission position is not a preset time domain position of the starting transmission. If the network equipment passes through (pass) LBT before slot0, DRS0-3 is sent at slot 0-3; if LBT passed before slot4, DRS0-3 is sent at slot 4-7; if LBT is passed before slot8, DRS0-3 is sent at slot 8-11; if LBT is passed before slot2, then DRS2, 3, 0, 1 is sent in sequence at slot 2-5.

When the network device sends the DRS to the terminal, the network device may send the sequence number of the DRS, the number of the DRSs that are continuously sent, and the offset coefficient (wrap around idx) to the terminal by being carried in the indication information included in the DRS. The offset coefficient of each DRS in the DRS group is the same. The same offset coefficients are only for the embodiment shown in fig. 7, and the offset coefficients of each DRS in the DRS group may also be different. Each DRS occupies one slot, and a DRS group includes 4 DRSs, so that the DRS group occupies 4 slots. Or carrying the numerical value of slot occupied by DRS and/or the time domain position of the initial DRS transmission group in the indication information. If the network device is configured to start to transmit the DRS group from the beginning of the radio frame, i.e., slot0, but actually start to transmit the DRS group at slot4, that is, the network device presets the time domain position where the DRS group is initially transmitted to be slot0, the time domain position where the network device actually starts to transmit the DRS group to be slot4, and the offset coefficient is the ratio of (slot4-slot0) to the number 4 of slots occupied by the DRS group, the offset coefficient is 1. If the network device is configured to start transmitting the DRS group at slot0, but actually start transmitting the DRS group at slot8, and the offset coefficient is a ratio of (slot8-slot0) to the number of slots occupied by the DRS group, which is 4, the offset coefficient is 2. If the network device is configured to start transmitting the DRS group at slot0, actually start transmitting the DRS group at slot0, and the offset coefficient is the ratio of (slot0-slot0) to the number of slots occupied by the DRS group, which is 4, the offset coefficient is 0.

After receiving any DRS, the terminal may determine, according to indication information included in the DRS, a value a of a slot occupied by the DRS and a sequence number b of the DRS, and determine, according to a (b +1), a number (third offset) of a slot, in which the network device presets to send the DRS, of a slot offset with respect to a slot, in which the network device presets to start sending a DRS group to which the DRS belongs. Taking DRS1 as an example, if b is 1 and a is 1, the number of slots in which the slot of the DRS with the transmission sequence number 1 is preset by the network device is offset from slot0 in which the network device presets the initial transmission of the DRS group is 1 × 1+1 — 2.

The terminal may further determine, according to the indication information, a time slot in which the network device actually starts to send the DRS group, and preset, with respect to the network device, the number of time slots (second offset) shifted from time slot0 in which the network device starts to send the DRS group, which may specifically be calculated by d × e × a.

And after determining that the network equipment actually sends the time slot number of the DRS, the terminal can carry out time synchronization with the network equipment.

The terminal can determine the timeslot number of the DRS group that the network device starts to transmit according to the actually received DRS timeslot number with sequence number 0, and the terminal knows that the DRS group transmitted by the network device occupies several timeslots, and the number of the timeslots occupied by the DRS group can be regarded as a period.

Another possible transmission method of synchronization information is shown in fig. 8, where the transmission position of the configured synchronization information group may start from the beginning of the radio frame (i.e. slot0 in each radio frame), or may start from a half frame of the radio frame, and when the subcarrier spacing SCS interval is 30kHz, 20slots are included in one 10ms radio frame, and slot10 is located at the half frame.

In fig. 8, it is assumed that the network device is configured to continuously transmit 4 DRS units in each DRS window, which is abbreviated as DRS hereinafter, and the sequence number (SSB QCL indication) is divided into 0 to 3, that is, a DRS group transmitted by the network device includes 4 DRSs, the time length (length) of the DRS is 1 slot, and the DRS group has 2 alternative initial transmission positions to cope with the influence of LBT. If the network equipment passes through LBT before slot0, DRS0-3 is sent at slot 0-3; if LBT is passed before slot4, DRS0-3 is sent at slot 4-7; if LBT is passed before slot10, DRS0-3 is sent at slot 10-13; if LBT is passed before slot14, DRS0-3 are transmitted at slots 14-17. If the network device is configured to transmit DRSs in the first 10 slots, the network device may choose not to transmit any DRSs in the present radio frame when LBT is passed before slot 8.

For the embodiment shown in fig. 8, because the network device configures two slots for starting to transmit the DRS group, in order to ensure that the terminal can accurately determine the slot for receiving any DRS, the network device needs to notify the terminal of the slot for starting to transmit the DRS group when the terminal transmits the DRS group this time, specifically, the slot for starting to transmit the DRS group may be directly carried in the indication information and notified to the terminal, or the indication information may be carried in the indication information and used for indicating the slot for starting to transmit the DRS group, for example, the slot for starting to transmit the DRS may be indicated by a half frame indication (half frame indication) in the DRS, fig. 8 provides an indication manner, if the half frame indication is 0, the slot for starting to transmit the DRS is the start of the radio frame, that is slot0, if the half frame indication is 1, the slot for starting to transmit the DRS is indicated as the half frame of the radio frame, for an SCS interval of 30khz, slot10 is at half frame.

The process of the terminal determining, according to the indication information, the time slot for the network device to preset the DRS may refer to the process described in fig. 7.

The above embodiments have been described only for the case where the transmission of the synchronization information group is delayed in the same radio frame, and the following description describes the transmission of synchronization information by the network device across radio frames.

When the network device transmits the synchronization information group, the synchronization information group may be transmitted across wireless frames, that is, the actually transmitted time domain position of the previous part of the synchronization information in the synchronization information group is in the previous wireless frame, the actually transmitted time domain position of the next part of the synchronization information in the synchronization information group is in the next wireless frame, and the previous wireless frame is adjacent to the next wireless frame. The time slot number calculated according to the formula in the possible implementation is larger than the maximum value of the time slot number included in the wireless frame, and in order to further determine the time slot number for actually receiving the synchronization information accurately, after the terminal determines the time slot number for actually receiving the synchronization information by adopting the formula, the maximum value of the time slot number included in the wireless frame radioframe at the current subcarrier interval can be obtained; and determining whether the number of the time slot actually receiving the synchronization information is greater than the maximum value; and if the difference value is larger than the maximum value, calculating the difference value between the number of the time slot actually receiving the synchronous information and the maximum value, and taking the difference value as the number of the time slot actually receiving the synchronous information.

Another possible transmission method of synchronization information is shown in fig. 9, where the transmission position of the configured synchronization information group may start from the beginning of the radio frame (i.e. slot0 in each radio frame), or may start from a half frame of the radio frame, and when the subcarrier spacing SCS interval is 30kHz, 20slots are included in one 10ms radio frame, and slot10 is located at the half frame.

In fig. 9, it is assumed that the network device is configured to continuously transmit 4 DRS units in each DRS window, which is abbreviated as DRS hereinafter, and the sequence number (SSB QCL indication) is divided into 0 to 3, that is, the DRS group transmitted by the network device includes 4 DRSs, the time length (length) of the DRS is 1 slot, and when the network device is configured to transmit the DRS group from the second half frame and the actual starting transmission position of the configured DRS group may span the radio frame, the DRS group has 4 alternative starting transmission positions to affect the LBT. Further, the network device is configured to transmit DRSs starting from slot 10. If the network equipment passes through LBT before slot10, DRS0-3 is sent at slot 10-13; if LBT is passed before slot14, DRS0-3 is sent at slots 14-17; if LBT passed before slot18, DRS0-3 is sent at slot1 from slot18 to the next radio frame; if the DRS passes LBT before slot2 of the next radio frame, DRS0-3 is sent at slot2-5 of the next radio frame; if slot0 of the next radio frame passes LBT, then the network device may transmit DRS2, 3, 0, 1, respectively, at slots 0-3 in the next radio frame.

When the network device passes LBT before slot18, and then sends DRS0-3 from slot18 to slot1 of the next radio frame (SFN ═ 1), when the network side indicates an offset, an optional implementation manner is: DRS0, 1 is located in the last 2 slots of radio frame 0, and its half frame indication (half frame indication) may be set to 1 (i.e. the DRS is located in the second half frame of the radio frame), but DRS2, 3 is located in the first 2 slots of radio frame 1, and its half frame indication ((half frame indication) is set to 0 (i.e. the DRS is located in the first half frame section of the radio frame).

As shown in fig. 9, the SFN corresponding to each DRS in the DRS group initially sent in slot10 and slot14 is 0, and in 4 DRSs in the DRS group initially sent in slot18, the SFNs corresponding to the first two DRSs are both 0, and the SFNs corresponding to the last two DRSs are both 1. In the 4 DRSs in the DRS group initially transmitted by slot18, SFNs corresponding to the first two DRSs are both 0, and SFNs corresponding to the last two DRSs in the 4 DRSs in the DRS group initially transmitted by slot2 of the DRS of the next radio frame may be set to 0 or may also be set to 1. The terminal can determine that the time domain position actually transmitting the DRS is the radio frame 1 through the relevant information of the DRS.

It should be noted that the above design is suitable for a scenario where the transmission time corresponding to the potential transmission position of the synchronization information is less than or equal to the duration of one radio frame (e.g., 10 ms). When the duration of each synchronization time is less than 1 slot, the UE determines which symbol in the corresponding slot number, in addition to the actually received slot number, after receiving the synchronization time.

For example, as shown in fig. 10, it is assumed that the network device is configured to continuously transmit 4 DRSunit, which is abbreviated as DRS hereinafter, in each DRS window, and the sequence number (SSB QCL indication) is divided into 0 to 3, that is, the network device transmits a DRS group including 4 DRSs, the time length (length) of the DRS is (7 symbols) and a half slot, and when the network device is configured to transmit the DRS group from a second half frame, the network device is configured to transmit the DRS from slot 10. If the network equipment passes through LBT before slot10, DRS0-3 is sent at slot 10-11; if LBT is passed before slot 12, DRS0-3 is sent at slots 12-14; if LBT is passed before slot14, DRS0-3 is sent at slots 14-16; DRS0-3 are transmitted on slots 16-18 if LBT is passed before slot 16.

The terminal can obtain an offset coefficient wrap around idx of the DRS, a DRS sequence number (idx), a field indication, the number of DRSs included in a DRS group, a slot number occupied by the DRS, a radio frame number, and the like.

If the wrap around idx of the DRS acquired by the terminal is 2, DRS idx is 1, half frame indication is 1, and SFN is 0, the terminal may calculate that the received DRS starts to be transmitted from symbol 7 in slot14 of SFN 0, and the transmission lasts for 7 symbols, that is, ends after slot 14.

Further, in the above embodiment, the network side only uses 1 bit in PBCH to indicate whether the preset starting transmission position of the DRS group is from slot0 or slot10 in one radio frame (assuming 30kHz subcarrier spacing). When the network side supports more flexible starting transmission positions in 1 radio frame, additional bits are needed to indicate, for example, when the network side can start transmission of DRSs at slot 0/5/10/15, the UE needs to obtain cell time synchronization through the additional indication.

For example, when the terminal side receives 1 DRS and then resolves to a wrap around idx of the DRS of 2, DRS idx of 1, and starting slot indication of 01(starting slot indication is equivalent to half frame identification, and they are different in that starting slot indication can indicate more possible DRS starting transmission positions), and when SFN of 0, the terminal side knows that the network side has a DRS starting transmission position of slot 5 in advance, it receives a DRS starting transmission from symbol 7 in slot 9 of SFN 0, and the transmission lasts for 7 symbols, that is, ends after slot 14.

When the network device only sends 1 DRS (minimum DRS unit) in each DRS window, the terminal may also obtain correct cell time synchronization by the above method, and it should be noted that when the number of time domain positions of the potential transmission (candidate) DRS is the same and the network side only sends 1 DRS, the value range of the corresponding offset coefficient wrapaund idx is larger, and therefore more bits are needed for indication. If there are 16 time domain positions of potential transmission DRSs in the DRS window, when the network side sends 1 DRS, the value of wrap around idx may be 0, 1, 2, … …, 16, and 5 bits are needed for indication; when the network side continuously transmits 4 DRSs, the numeric area idx value range may be 0, 1, 2, 3, 4, and 3 bits are needed for indication.

The network side can indicate wrap around idx in PBCH, can indicate wrap around idx in PBCH DMRS, can jointly indicate wrap around idx through PBCH and PBCH DMRS, and can obtain actual wrap around idx through formula/calculation based on PBCH and PBCH DMRS joint indication information.

Based on the same concept as the time synchronization method, as shown in fig. 11, an embodiment of the present application further provides a time synchronization apparatus 1100, where the time synchronization apparatus 1100 is configured to perform operations performed by a terminal and a network device in the time synchronization method.

The time synchronization apparatus 1100 includes: a processing module 1101, a sending module 1102 and a receiving module 1103; the sending module 1102 is configured to send data; the receiving module 1103 is configured to receive data.

When the time synchronization apparatus executes a step executed by a terminal, for example, the receiving module 1103 is configured to receive synchronization information sent by a network device, where the synchronization information includes indication information, and the indication information is used to indicate a time domain position where the network device actually sends the synchronization information;

a processing module 1101, configured to determine, according to the indication information, a time domain position where the synchronization information is actually received.

Optionally, the indication information includes:

the number of the received synchronous information in the synchronous information group to which the synchronous information belongs, the offset coefficient of the received synchronous information and the serial number of the received synchronous information;

the offset coefficient is a multiple of the offset between the time domain position of the synchronization information group to which the synchronization information belongs, which is actually sent by the network equipment at the beginning, and the time domain position of the synchronization information group to which the synchronization information belongs, which is preset by the network equipment at the beginning, and the number of the time domains occupied by the synchronization information group to which the synchronization information belongs.

The time domain locations include: numbering time slots;

a processing module 1101, configured to, when determining, according to the indication information, a time domain position at which the synchronization information is actually received, specifically, according to a formula: m ═ a × b + c + d × e × a, and a slot number for actually receiving the synchronization information is determined;

the method comprises the steps that m is a time slot number for actually receiving the synchronous information, a is a numerical value of a time slot occupied by the synchronous information, b is a serial number of the synchronous information, c is a time slot number of a synchronous information group to which the synchronous information is preset to be sent initially, d is a synchronous information offset coefficient, e is the number of the received synchronous information in the synchronous information group to which the synchronous information belongs, b is an integer equal to or greater than 0, and d is an integer equal to or greater than 0.

Optionally, the processing module 1101 is configured to, after determining a timeslot number for actually receiving the synchronization information, obtain a maximum value of timeslot numbers included in a radio frame of a radio frame at a current subcarrier interval;

determining whether the number of the time slot actually receiving the synchronization information is larger than the maximum value;

if so, calculating the difference value between the number of the time slot actually receiving the synchronous information and the maximum value, and taking the difference value as the number of the time slot actually receiving the synchronous information.

Based on the same technical concept as the time synchronization method, as shown in fig. 12, an embodiment of the present application further provides a time synchronization apparatus 1200, where the time synchronization apparatus 1200 is configured to perform an operation performed by a terminal or a network device in the time synchronization method.

The time synchronization apparatus 1200 includes: the processor 1201 and the transceiver 1202, optionally, also include a memory 1203. The processor 1201 is configured to call a set of programs, and when the programs are executed, the processor 1201 is configured to perform the operations performed by the terminal and the network device in the time synchronization method. The memory 1203 is used for storing programs executed by the processor 1201. The processing module 1101 in fig. 11 may be implemented by the processor 1201, and the sending module 1102 and the receiving module 1103 may be implemented by the communication interface 1202.

The processor may be a Central Processing Unit (CPU), a Network Processor (NP), or a combination of a CPU and an NP.

The processor may further include a hardware chip or other general purpose processor. The hardware chip may be an application-specific integrated circuit (ASIC), a Programmable Logic Device (PLD), or a combination thereof. The aforementioned PLDs may be Complex Programmable Logic Devices (CPLDs), field-programmable gate arrays (FPGAs), General Array Logic (GAL) and other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc., or any combination thereof. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

It will also be appreciated that the memory referred to in the embodiments of the application may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The non-volatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable PROM (EEPROM), or a flash Memory. Volatile Memory can be Random Access Memory (RAM), which acts as external cache Memory. By way of example, but not limitation, many forms of RAM are available, 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 (DDR SDRAM), Enhanced Synchronous SDRAM (ESDRAM), Synchronous link SDRAM (SLDRAM), and Direct Rambus RAM (DR RAM). It should be noted that the memory described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

The embodiment of the application provides a computer storage medium, which stores a computer program, wherein the computer program comprises a program for executing the time synchronization method.

Embodiments of the present application provide a computer program product containing instructions that, when executed on a computer, cause the computer to perform the time synchronization method provided above.

Any one of the time synchronization devices provided by the embodiments of the present application may also be a chip.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While the preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various changes and modifications may be made in the embodiments of the present application without departing from the spirit and scope of the embodiments of the present application. Thus, if such modifications and variations of the embodiments of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to encompass such modifications and variations.

Claims

1. A method of time synchronization, comprising:

a terminal receives synchronization information sent by network equipment, wherein the synchronization information comprises indication information, and the indication information is used for indicating a time domain position of the network equipment for actually sending the synchronization information;

and the terminal determines the time domain position for actually receiving the synchronous information according to the indication information.

2. The method of claim 1, wherein the synchronization information comprises:

the reference signal DRS or the synchronization signal block SSB is found.

3. The method of claim 1 or 2, wherein the indication information comprises:

the network equipment actually sends the time domain position of the time synchronization information; or the like, or, alternatively,

the offset between the time domain position of the network equipment which actually sends the synchronization information and the time domain position of the network equipment which presets the synchronization information group which starts sending the synchronization information; or the like, or, alternatively,

the offset between the time domain position of the synchronization information group to which the network device actually starts sending the synchronization information and the time domain position of the synchronization information group to which the network device presets starting sending the synchronization information, and the offset between the time domain position of the synchronization information to which the network device presets sending the synchronization information and the time domain position of the synchronization information group to which the network device presets starting sending the synchronization information;

wherein the synchronization information group comprises one or more continuously transmitted synchronization information.

4. The method of any one of claims 1-3, wherein the indication information comprises:

5. The method of claim 4, wherein the time domain location comprises: numbering time slots;

the terminal determines the time domain position actually receiving the synchronization information according to the indication information, and the method comprises the following steps:

the terminal is according to the formula: m ═ a × b + c + d × e × a, and a slot number for actually receiving the synchronization information is determined;

the method comprises the steps that m is a time slot number for actually receiving the synchronous information, a is a numerical value of a time slot occupied by the synchronous information, b is a serial number of the synchronous information, c is a time slot number for presetting a synchronous information group to which the synchronous information is initially sent, d is a synchronous information offset coefficient, e is the number of the received synchronous information in the synchronous information group to which the synchronous information belongs, b is an integer equal to or larger than 0, d is an integer equal to or larger than 0, and the time slot number is an integer equal to or larger than 0.

6. The method of claim 5, wherein after determining the slot number at which the synchronization information is actually received, the terminal further comprises:

acquiring the maximum value of the time slot number included in a radio frame under the current subcarrier interval;

7. The method of claim 5, wherein the slot occupied by the synchronization information is pre-stored or included in indication information.

8. The method of claim 5, wherein a slot number of a synchronization information group to which the synchronization information is to be transmitted at the start is preset to be stored in advance or included in indication information.

9. An apparatus for time synchronization, comprising:

the system comprises a receiving module, a sending module and a receiving module, wherein the receiving module is used for receiving synchronous information sent by network equipment, the synchronous information comprises indication information, and the indication information is used for indicating a time domain position of the network equipment for actually sending the synchronous information;

and the processing module is used for determining the time domain position for actually receiving the synchronous information according to the indication information.

10. The apparatus of claim 9, wherein the synchronization information comprises:

the reference signal DRS or the synchronization signal block SSB is found.

11. The apparatus of claim 9 or 10, wherein the indication information comprises:

12. The apparatus of any of claims 9-11, wherein the indication information comprises:

13. The apparatus of claim 12, wherein the time domain location comprises: numbering time slots;

a processing module, configured to, when determining, according to the indication information, a time domain position at which the synchronization information is actually received, specifically:

according to the formula: m ═ a × b + c + d × e × a, and a slot number for actually receiving the synchronization information is determined;

14. The apparatus of claim 13, wherein the processing module is further configured to obtain a maximum value of slot numbers included in a radio frame at a current subcarrier spacing after determining a slot number for actually receiving the synchronization information; determining whether the number of the time slot actually receiving the synchronization information is larger than the maximum value; if so, calculating the difference value between the number of the time slot actually receiving the synchronous information and the maximum value, and taking the difference value as the number of the time slot actually receiving the synchronous information.

15. The apparatus of claim 13, wherein the slot occupied by the synchronization information is pre-stored or included in indication information.

16. The apparatus of claim 13, wherein a slot number of a synchronization information group to which the synchronization information is preset to be initially transmitted is pre-stored or included in indication information.

17. A computer-readable storage medium having computer-readable instructions stored therein which, when executed, cause an apparatus to perform the method of any one of claims 1-8.

18. A computer program product, which, when read and executed by a computer, causes the computer to perform the method of any one of claims 1 to 8.

19. A chip, wherein the chip is coupled to a memory for reading and executing a software program stored in the memory to implement the method of any one of claims 1-8.