CN110582113B

CN110582113B - Synchronous time indication and synchronization method, device and terminal in direct connection link

Info

Publication number: CN110582113B
Application number: CN201910943357.6A
Authority: CN
Inventors: 张晋瑜; 曲鑫
Original assignee: Beijing Ziguang Zhanrui Communication Technology Co Ltd
Current assignee: Beijing Ziguang Zhanrui Communication Technology Co Ltd
Priority date: 2019-09-30
Filing date: 2019-09-30
Publication date: 2022-02-08
Anticipated expiration: 2039-09-30
Also published as: CN110582113A

Abstract

A method, a device and a terminal for indicating and synchronizing the synchronization time in a direct link are provided, wherein the method for indicating the synchronization time in the direct link comprises the following steps: generating a period indicator according to the sending time of the S-SSB, wherein the period indicator is used for representing the position of the sending period of the sending time of the S-SSB in a wireless frame number period; determining a synchronization resource indicator according to synchronization resources used for transmitting the S-SSB; and generating a synchronization time indicator according to the period indicator and the synchronization resource indicator. By the method, the original DFN or SFN is replaced by the synchronous time indicator, the bit number required by indicating the radio frame number is reduced, more PSBCH payload space is released, and more bit numbers are reserved for indicating SL-BWP and SL TDD UL-DL configuration.

Description

Synchronous time indication and synchronization method, device and terminal in direct connection link

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method, an apparatus, and a terminal for indicating and synchronizing synchronization time in a direct link.

Background

In the current mobile communication system, one radio frame corresponds to 10ms in the time domain, and includes 10 subframes of 1 ms. The range of System Radio Frame numbers is [0,1023], which may be indicated by a 10-bit System Frame Number (SFN), such as a 10-bit SFN Number in a Master Information Block (MIB) of 5G (New Radio, NR) and a Direct Frame Number (DFN) of 10bits in a Direct path MIB (SL-MIB) in a vehicle networking (LTE vehicle X, i.e., V2X). Referring to table 1, table 1 provides a content diagram of an existing LTE V2X SL-MIB; the DFN is indicated by 10bits, and the 10 possible subframe numbers are indicated by 4-bit directSubFrameNumbers. Each synchronization resource in LTE V2X occupies one subframe, i.e., 1ms duration.

TABLE 1

Unlike the relatively fixed BandWidth (BW) and Time Division duplex (TDD UL-DL) configurations of the LTE system, NR introduces more flexibility to these configurations, such as more flexible partial BandWidth (BWP) and TDD UL-DL configurations, which correspondingly needs to occupy more bits, especially for TDD UL-DL configurations. If the configuration mode of the link between the NR terminal and the base station (Uu) is adopted, the bi-periodic TDD UL-DL configuration requires 63 bits. According to the current progress of the 3GPP conference, the payload (payload) of the Physical Sidelink Broadcast Channel (PSBCH) is 56 bits, which includes 24 bits of CRC check bits, and if the existing indication manner of DFN or SFN in the Sidelink is adopted, the payload in the existing PSBCH is far insufficient to carry the configuration information in the NR.

Disclosure of Invention

The technical problem solved by the present application is how to release more PSBCH payloads, leaving more bits for indicating SL-BWP and SL TDD UL-DL configurations.

In order to solve the foregoing technical problem, an embodiment of the present application provides a method for indicating synchronization time in a direct link, where the method includes: generating a period indicator according to the sending time of the S-SSB, wherein the period indicator is used for representing the position of the sending period of the sending time of the S-SSB in a wireless frame number period; determining a synchronization resource indicator according to synchronization resources used for transmitting the S-SSB; and generating a synchronization time indicator according to the period indicator and the synchronization resource indicator.

Optionally, the period indicator occupies N1 bits, wherein,

x is the length of the period of the DFN or SFN, Y is the length of the transmission period of the S-SSB,

is the rounding up of the logarithm.

Alternatively, when X is 10240ms and Y is 160ms, N1 is 6.

Optionally, the synchronization resource indicator occupies N2 bits, wherein,

z is the number of synchronization resources configured in each transmission cycle.

Optionally, when Z is 2, N2 is 1; when Z is 3 or 4, N2 is 2.

Optionally, the method further includes: and transmitting the synchronization time indicator in a PSBCH (pseudo-broadcast channel) in whole or in part.

Optionally, if the number of S-SSBs preconfigured on each set of synchronization resources in each sending period is greater than 1; sending a number of the S-SSB, the number being used to determine a time offset of the S-SSB on synchronization resources within the sending period.

A method of synchronization in a direct connection link, the method comprising: acquiring a synchronization time indicator, wherein the synchronization time indicator comprises a period indicator and a synchronization resource indicator, the period indicator is used for representing the position of a sending period in a wireless frame number period at the sending time of the S-SSB, and the synchronization resource indicator is used for determining the synchronization resource used by a sending end for sending the S-SSB; determining the sending period of the S-SSB according to the period indicator; determining the offset of the synchronization resource used by the S-SSB in the sending cycle of the S-SSB according to the synchronization resource indicator and the pre-configuration information; and calculating the position of the S-SSB according to the sending period of the S-SSB and the offset.

Optionally, when the number of the S-SSBs preconfigured on each set of synchronization resources in each sending period is 1, the preconfigured information includes a time domain offset sent by the S-SSBs in each synchronization resource.

Optionally, when the number of the S-SSBs preconfigured on each set of synchronization resources in each sending period is greater than 1, each S-SSB has a number; the method further comprises the following steps: receiving the serial numbers of the S-SSBs, wherein the preconfigured information comprises the corresponding relation between the S-SSBs of each serial number and the time domain offset of the S-SSBs on the synchronous resources; the determining, according to the synchronization resource indicator and the preconfigured information, an offset of a synchronization resource used by the S-SSB in a transmission cycle in which the S-SSB is located includes: determining the synchronous resources used by each S-SSB according to the synchronous resource indicator; and determining the offset of each S-SSB in the sending period of the S-SSB according to the serial number of the S-SSB and preset configuration information.

The embodiment of the present application further provides a device for indicating synchronization time in a direct link, where the device includes: the system comprises a period indicator determining module, a wireless frame number determining module and a wireless frame number determining module, wherein the period indicator determining module is used for generating a period indicator according to the sending time of the S-SSB, and the period indicator is used for representing the position of the sending period of the sending time of the S-SSB in a wireless frame number period; a synchronization resource indicator determining module, configured to determine a synchronization resource indicator according to a synchronization resource used for sending the S-SSB; and the wireless frame number indicator generating module is used for generating a synchronous time indicator according to the period indicator and the synchronous resource indicator.

An embodiment of the present application further provides a synchronization apparatus in a direct link, where the apparatus includes: a synchronization time indicator obtaining module, configured to obtain a synchronization time indicator, where the synchronization time indicator includes a period indicator and a synchronization resource indicator, where the period indicator is used to characterize a position of a transmission period in a radio frame number period at a transmission time of an S-SSB, and the synchronization resource indicator is used to determine a synchronization resource used by a transmitting end to transmit the S-SSB; a sending cycle position determining module, configured to determine, according to the cycle indicator, a position of a sending cycle in which the S-SSB is located in a radio frame number cycle; an offset determining module, configured to determine, according to the synchronization resource indicator and preconfigured information, an offset of a synchronization resource used by the S-SSB in a sending cycle in which the S-SSB is located; and the sending position determining module is used for calculating the position of the S-SSB according to the sending period of the S-SSB and the offset.

The embodiment of the present application further provides a user terminal, which includes a memory and a processor, where the memory stores computer instructions capable of being executed on the processor, and the processor executes the computer instructions to perform the steps of any one of the above methods.

A storage medium having stored thereon computer instructions which, when executed, perform the steps of any of the above-described methods.

Compared with the prior art, the technical scheme of the embodiment of the application has the following beneficial effects:

the embodiment of the application provides a method for indicating synchronous time in a direct connection link, which comprises the following steps: generating a period indicator according to the sending time of the S-SSB, wherein the period indicator is used for representing the position of the sending period of the sending time of the S-SSB in a wireless frame number period; determining a synchronization resource indicator according to synchronization resources used for transmitting the S-SSB; and generating a synchronization time indicator according to the period indicator and the synchronization resource indicator. Compared with the prior art, the method has the advantages that the synchronization time indicator is generated by using the period indicator corresponding to the transmission period of the S-SSB and the synchronization resource indicator corresponding to the synchronization resource for transmitting the S-SSB, the original DFN or SFN is replaced by the synchronization time indicator, the bit number required by indicating the radio frame number is reduced, more PSBCH payload space is released, and therefore more bit numbers are reserved for indicating SL-BWP and SLTDD UL-DL configuration.

Further, the generated synchronization time indicator comprises a period indicator of 6 bits and a synchronization resource indicator of 0 to 2 bits, and when the synchronization time indicator is used as a DFN or SFN indication mode of the optimized Sidelink, the number of bits required for indicating the radio frame number is reduced, thereby leaving more bits for indicating the SL-BWP and SL tdd ul-DL configurations.

Further, the number of the S-SSBs preconfigured on each group of synchronization resources in each sending period by the sending terminal may be 1 or more than 1, and when the number of the S-SSBs preconfigured on each group of synchronization resources in each sending period is 1, the receiving terminal may directly calculate the slot number according to the preconfigured information without indicating the S-SSB number. When the number of the S-SSBs preconfigured on each group of synchronous resources in each sending period is greater than 1, the sending terminal needs to send the serial number of the S-SSB, so that the receiving terminal calculates the slot serial number according to the serial number of the S-SSB and determines the time domain position sent by the S-SSB.

Drawings

Fig. 1 is a schematic flowchart of a method for indicating a synchronization time in a direct link according to an embodiment of the present application;

fig. 2 is an application diagram of a method for indicating synchronization time in a direct link according to an embodiment of the present application

Fig. 3 is a schematic diagram illustrating a correspondence relationship between a period indicator and a DFN or SFN according to an embodiment of the present application;

FIG. 4 is a timing diagram illustrating two types of transmission timing sequences for synchronization resource reservation according to an embodiment of the present disclosure;

fig. 5 is a schematic diagram of an S-SSB transmission time domain according to an embodiment of the present application;

FIG. 6 is a time domain diagram of a local layout method of an S-SSB in a transmission period according to an embodiment of the present application;

FIG. 7 is a time domain diagram of a distributed layout method of an S-SSB in a transmission period according to an embodiment of the present application;

fig. 8 is a flowchart illustrating a synchronization method in a direct link according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a synchronous time indication device in a direct connection link according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of a synchronization apparatus in a direct link according to an embodiment of the present application.

Detailed Description

As mentioned in the background, the SFN or DFN indicated by the conventional radio frame number takes 10bits, and the payload in the existing PSBCH is far from sufficient to carry this information for more flexible BWP and TDD UL-DL configurations in NR.

Compared with the prior art, the technical scheme of the application generates the synchronous time indicator by using the cycle indicator corresponding to the transmission cycle of the S-SSB and the synchronous resource indicator corresponding to the synchronous resource for transmitting the S-SSB, replaces the original DFN or SFN with the synchronous time indicator, reduces the bit number required by indicating the radio frame number, releases more PSBCH payload space, and reserves more bit numbers for indicating the configuration of the SL-BWP and the SL TDD UL-DL.

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying the present application are described in detail below with reference to the accompanying drawings.

Referring to fig. 1 to 3, fig. 1 provides a flow chart of a method for indicating a synchronization time in a direct link according to an embodiment; fig. 2 provides an application diagram of a synchronization time indication method in a direct connection link; fig. 3 provides a diagram illustrating the correspondence between the period indicator and the DFN or SFN in an example.

As shown in fig. 1, a method for indicating synchronization time in a direct link provided in an embodiment of the present application may specifically include the following steps:

s102, generating a period indicator according to the sending time of the S-SSB, wherein the period indicator is used for representing the position of the sending period of the sending time of the S-SSB in a wireless frame number period.

A direct connection Synchronization information block (Sidelink SS or PSBCH block, S-SSB, where SS is an abbreviation of Synchronization signal) is an information block that is sent by a sending terminal to a receiving terminal and used for the receiving terminal to synchronize with the sending terminal in the SL communication process. The sending period of the S-SSB is fixed and can be set by specific environment, such as 160 ms.

In the Sidelink communication, a sending terminal can send a SL-MIB to a receiving terminal, and indicate the time domain position sent by the S-SSB through an SFN or DFN in the SL-MIB, and the receiving terminal determines the time domain position sent by the S-SSB and the adopted synchronization resource according to the received SFN or DFN and the preconfigured information.

The sending time of the S-SSB is the time domain position of the S-SSB sent by the sending terminal to the receiving terminal, and in the prior art, the time domain position of the S-SSB in the radio frame number period is determined according to the corresponding DFN or SFN indicated by the DFN information in the SL-MIB. In the Sidelink communication, if the terminal is synchronized to the base station, the DFN in the SL-MIB is the SFN in the base station MIB at this time.

In step S102, after the transmission period of the S-SSB is determined, each radio frame period may be divided into a plurality of transmission periods. In the method, the sending period after each wireless frame period is segmented is labeled, and a period indicator is generated according to the label of the period where the sending time of the S-SSB to be sent is located. If the transmission period of the S-SSB is 160ms, the radio frame period is 10240ms, each radio frame period can be divided into 64 transmission periods, the labels of the 64 transmission periods are 0-63, and the binary bit identifiers are 000000-111111, and the specific correspondence relationship can be seen in fig. 3.

S104, according to the synchronous resource used for sending the S-SSB, the synchronous resource indicator is determined.

The synchronization resource indicator is an indicator for determining a synchronization resource for transmitting the S-SSB, and may be several bits of information. The synchronization resource selected by a terminal depends on the state of the terminal and its synchronization source.

The selection of the synchronization resource by the sending terminal can be specifically divided into the following cases: if the transmitting terminal is synchronized to the base station, the synchronization is determined according to the indication of the System Information Block (SIB) transmitted by the base station, wherein the indication in the SIB21 or the SIB26 may be specifically determined in LTE V2X.

If the transmitting terminal is synchronized to a Global Navigation Satellite System (GNSS), the synchronization is determined according to an indication of SIB21 or SIB26 sent by the base station, or according to a preset configuration, for example, a first or third resource in synchronization resources of the preset configuration is adopted.

If the terminal is synchronized to another terminal, which is referred to as a synchronization source terminal (UE), a resource different from the synchronization source UE is used. Referring to fig. 4, fig. 4 is a timing diagram of two synchronization resource presets according to an embodiment; which contains two sets of synchronization resources SLSS resource1 and slsresource 2. In one example, when the sending terminal UE-B synchronizes to another synchronization source terminal UE-a, the determination of the synchronization resource may be as follows: if UE-A sends SL-SS on SLSS resource1, UE-B hears the information on SLSS resource1 and determines that UE-A uses SLSS resource1 through the pre-configuration information. When UE-B also needs to send SL-SS, another resource, SLSS resource2, is used. Therefore, the UE-B can be ensured to receive or send the synchronous information on different synchronous resources, and the half-duplex problem is avoided.

And if the sending terminal does not have the synchronization source, randomly selecting the multiple groups of synchronization resources in the pre-configuration, for example, selecting the first group from the 2 groups of synchronization resources in the pre-configuration.

Under the condition of different synchronous sources, the method for determining the synchronous resources of the sending S-SSB ensures that the sending terminal can select proper synchronous resources under each synchronous source to realize effective synchronization.

And S106, generating a synchronous time indicator according to the cycle indicator and the synchronous resource indicator.

Combining the cycle indicator in step S102 and the synchronization resource indicator in step S104 to generate a synchronization time indicator for indicating the time domain position of S-SSB transmission, instead of the indication information of DFN or SFN in existing LTE or NR 5G.

The above-mentioned method for indicating synchronization time in a direct link may be applied to the transmitting terminal 201 in fig. 2, which generates a synchronization time indicator by using a cycle indicator and a synchronization resource indicator corresponding to a synchronization resource used for transmitting S-SSB, replaces the original indication information of DFN or SFN with the synchronization time indicator, reduces the number of bits required for indicating a radio frame number, and releases more PSBCH payload space, thereby leaving more bits for indicating SL-BWP and SL TDD UL-DL configurations.

Optionally, the period indicator occupies N1 bits, wherein,

is the rounding up of the logarithm.

The bit occupied by the period indicator is according to the formula

And (4) determining. I.e., the period indicator is expressed in terms of the number of transmission periods contained in a period of the DFN or SFN and converted into binary bits.

Further, when X is 10240ms and Y is 160ms, N1 is 6.

According to the current conference evolution of 3GPP, the S-SSB transmission period is 160ms, corresponding to 16 DFNs or SFNs (10 ms for one radio frame). And the value range of the DFN or SFN number is [0,1023], and 10-bit indication is needed. A full radio frame number DFN or SFN period (10240ms) may be divided into 64S-SSB periods (10240/160 ═ 64), with the position of each 160ms S-SSB period in the radio frame number period 10240ms corresponding exactly to the upper 6 bits of the DFN or SFN. That is, the period indicator of step S102 in fig. 1 may refer to the first 6 bits of the original DFN or SFN.

In one embodiment, the synchronization resource indicator occupies N2 bits, wherein,

The synchronization resource indicator is used for converting the number of the configured synchronization resources in each transmission period into a binary bit for representing.

Further, when Z is 2, N2 is 1; when Z is 3 or 4, N2 is 2.

The synchronization resources in the current SL are usually preconfigured with 2 or 3 groups, and the number of bits occupied by the synchronization resources is 1 bit or 2 bits.

If 1 group of synchronous resources are configured, the synchronous resources are automatically used for realizing communication without specifying the synchronous resources, and the indicator of the synchronous resources is 0 bit.

If 2 sets of synchronization resources are configured, a 1-bit synchronization resource indicator is required. For example, a first set of synchronization resources is indicated when the synchronization resource indicator takes a value of 0; when the synchronization resource indicator takes a value of 1, it indicates the 2 nd group of synchronization resources.

If 3 or 4 sets of synchronization resources are configured, a 2-bit synchronization resource indicator is required. For example, when the synchronization resource indicator takes the value 00, it represents the 1 st group of synchronization resources; when the synchronization resource indicator value is 01, the 2 nd group of synchronization resources are represented; when the synchronization resource indicator takes the value of 10, the 3 rd group of synchronization resources are represented, and when the synchronization resource indicator takes the value of 11, the 4 th group of synchronization resources are represented. Currently, 2 or 3 groups of synchronization resources are preconfigured on one frequency point of the Sidelink communication.

Through the scheme, the generated synchronization time indicator comprises the period indicator with 6 bits and the synchronization resource indicator with 1 to 2 bits, and when the synchronization time indicator is used as a DFN or SFN indicating mode of the optimized Sidelink, the bit number required for indicating the radio frame number is reduced, so that more bit numbers are reserved for indicating SL-BWP and SLTDD UL-DL configurations.

In an embodiment, the method for indicating the synchronization time in the direct link further includes: and transmitting the synchronization time indicator in a PSBCH (pseudo-broadcast channel) in whole or in part.

A Physical Broadcast Channel (PSBCH), a synchronization time indicator may replace the indication information of the DFN or SFN, and a part or all of the synchronization time indicator is carried in the PSBCH and transmitted from the transmitting terminal to the receiving terminal, and the receiving terminal may implement synchronization with the transmitting terminal according to the received SL-MIB.

Referring to fig. 2, fig. 2 provides an application diagram of a method for indicating synchronization time in a direct link; the above-described synchronization time indicator may be generated by the transmitting terminal 201 in fig. 2 and transmitted in the PSBCH in its entirety. For example, continuing to refer to fig. 3 to fig. 4, when the transmission period is 160ms, if the transmitting terminal transmits S-SSB on Resource1 (SLSS Resource1 in fig. 4), the synchronization Resource indicator carried in the PSBCH transmitted by the transmitting terminal is 0, which indicates that the S-SSB transmitted by the transmitting terminal is on Resource (SLSS Resource1) 1; the value of the high 6 bits of the DFN or SFN in the PSBCH is the position of the transmission cycle in which the transmission time of the S-SSB is located in the radio frame cycle, and the specific value depends on the transmission time of the S-SSB. If the first 160ms (namely the DFN or SFN takes the value of 0000000000-0000001111), 00000 (namely the upper 6 bits of the DFN or SFN) is used as the period indicator; if the second 160ms (i.e. the DFN or SFN takes the values of 0000001000-0000011111), 00001 (i.e. the upper 6 bits of the DFN or SFN) is used as the period indicator, and so on.

In addition, a part of bits in the synchronization time indicator may be carried by a PSBCH Demodulation Reference Signal (DMRS) or PSBCH scrambling sequence. For example, a 1 or 2 bit synchronization resource indicator is carried by a DMRS sequence, and a period indicator is indicated in a PSBCH; or the upper three bits of the periodic indicator are carried by the DMRS sequence, and the lower three bits are indicated in the PSBCH.

In one embodiment, if the number of the S-SSBs preconfigured on each set of synchronization resources in each sending period is greater than 1, sending a number of the S-SSBs, wherein the number is used for determining the time offset of the S-SSBs on the synchronization resources in the sending period.

Specifically, the number of S-SSBs preconfigured by the sending terminal on each set of synchronization resources in each sending period may be 1 or more than 1.

When the transmitting terminal only pre-configures one S-SSB transmission in each transmission period, each set of pre-configured resources occupies only one slot (slot), which is similar to the transmission case of the SSB in LTE V2X. The sending terminal sends the synchronization time indicator to enable the receiving terminal to know the time domain position sent by the S-SSB, at this time, the sending terminal indicates the resource for sending the S-SSB through the synchronization resource indicator, which is also equivalent to determining the slot number corresponding to the S-SSB, and the sending terminal does not need to indicate a subframe (subframe) number of 4 bits, namely the number of the S-SSB.

Referring to fig. 5, fig. 5 provides a schematic diagram of the S-SSB transmission time domain in an embodiment; at this time, the transmission period is 160ms, and includes 2 sets of synchronization resources in total, and the current synchronization resource indicator indicates resource 2. The sending terminal can use the synchronous time indicator to represent the time domain position DFN index of the time domain position of the S-SSB in the wireless frame period, thereby realizing the function of indicating information of DFN or SFN in the original MIB. Specifically, the synchronization time indicator may include: a 6-bit period indicator 000010 (indicating the third transmission period in each radio frame period), and a 1-bit synchronization resource indicator 1 (indicating resource 2). As can be seen from fig. 5, at this time, it is necessary to determine the offset2 of the synchronization resource used by the S-SSB in the transmission cycle of the S-SSB, so as to determine the DFN index, and this offset2 can be determined by the preconfigured information of resource2, and does not need to be transmitted in the synchronization time indicator.

When a sending terminal pre-configures 2 or more than 2S-SSBs in each sending period for sending, each set of pre-configured resources occupies 2 or more than 2 (slots), a fixed S-SSB layout method (pattern) needs to be designed as NR DL SSB, each S-SSB in each sending period is labeled according to the time domain sequence, and if N S-SSBs exist in each sending period, the S-SSB label in each sending period is 0-N-1. The sending terminal needs to send the number of the S-SSB, so that the receiving terminal determines the relative time offset of the S-SSB in the layout method according to the number of the S-SSB and the fixed time domain position of the S-SSB of each number in the pre-configuration information corresponding to the synchronization resource, and the time domain position of the S-SSB in the wireless frame number period is determined.

The transmitting terminal may carry all the numbers of the S-SSBs in the PSBCH for transmission, or may indicate the numbers of the S-SSBs through a PSBCH DMRS sequence or a PSBCH scrambling sequence in part of bits thereof. As in the current NR Downlink (DL) with 6-bit SSB number information for indicating 64 SSBs, where the low three bits are carried by PBCH DMRS sequences and the high three bits are carried in PBCH. The layout method of the S-SSB in each sending period may specifically include two layout methods:

local layout method (Localized pattern): referring to fig. 6, fig. 6 provides a time domain schematic diagram of a local layout method of the S-SSB in a transmission period; the N S-SSBs are relatively localized in the time domain, e.g., all localized within a 5ms time window. At this time, the method of LTE V2X can be followed by using the synchronization offset (sync offset) to determine the start position of the 5ms S-SSB transmission time window, and then determining the relative offset of each S-SSB within the 5ms window according to the number of the S-SSB.

Distributed layout method (Distributed pattern): referring to fig. 7, fig. 7 provides a time domain diagram of a distributed layout method of S-SSB in a sending period; the positions of the N S-SSBs in the time domain are relatively dispersed. It may not be good to follow the approach of syncOffset of LTE V2X to indicate discrete multiple S-SSB resources. However, as long as the time domain resource positions of each S-SSB on each set of synchronization resources are relatively fixed, the relative offset of each S-SSB in each sending period can be determined in the preconfigured information of the synchronization resources, and the receiving terminal can obtain the relative offset corresponding to the number of the S-SSB by querying the preconfigured information according to the received number of the S-SSB, and then obtain the corresponding time domain position of the S-SSB in the radio frame number period by combining the sending period corresponding to the period indicator.

For example, the transmitting terminal indicates the number of the transmitted S-SSB (denoted by S-SSB index in this example), and if the transmitting terminal transmits at the positions of S-SSB 0 and 1 on the synchronization resource1, the S-SSB index carried in the corresponding PSBCH is 0 or 1.

In this embodiment, the number of S-SSBs preconfigured on each group of synchronization resources in each sending period by the sending terminal may be 1 or greater than 1, and when the number of S-SSBs preconfigured on each group of synchronization resources in each sending period is 1, the receiving terminal may directly calculate the slot number according to the preconfigured information without indicating the S-SSB number. When the number of the S-SSBs preconfigured on each group of synchronous resources in each sending period is greater than 1, the sending terminal needs to send the serial number of the S-SSB, so that the receiving terminal calculates the slot serial number according to the serial number of the S-SSB and determines the time domain position sent by the S-SSB.

The present application further provides a synchronization method in a direct link, where the method may be implemented in the receiving terminal 202 in fig. 2, and a flow of the synchronization method in the direct link is shown in fig. 8, where the method specifically includes:

step S802, a synchronization time indicator is obtained, where the synchronization time indicator includes a period indicator and a synchronization resource indicator.

The period indicator is used for representing the position of a sending period in a radio frame number period at the sending time of the S-SSB, and the synchronous resource indicator is used for determining synchronous resources used by a sending end for sending the S-SSB.

Step S804, determining the sending period of the S-SSB according to the period indicator.

Step S806, according to the synchronization resource indicator and the pre-configuration information, determining the offset of the synchronization resource used by the S-SSB in the sending cycle of the S-SSB.

And step S808, calculating the position of the S-SSB according to the sending period of the S-SSB and the offset.

Corresponding to the sending terminal in fig. 1, the receiving terminal receives the synchronization time indicator sent by the sending terminal, determines that the sending period in which the S-SSB is located is the several sending period in the DNF index according to the period indicator, and determines the synchronization resource for receiving the S-SSB according to the synchronization resource indicator. And the receiving terminal acquires the offset of each S-SSB in the sending period according to the pre-configuration information corresponding to the determined synchronous resource, thereby determining the sending position of the S-SSB. To replace the indication information of DFN or SFN in the prior art.

If the transmission period is 160ms, the receiving terminal receives the synchronization time indicator and the number of the S-SSB, and can determine the first 6 bits of the SFN or DFN indication information corresponding to the transmission period of the S-SSB according to the period indicator; according to the synchronous resource indicator 1, determining to send the S-SSB on the synchronous resource1, and determining corresponding pre-configuration information; and inquiring the time offset of the S-SSB corresponding to the S-SSB number in the pre-configuration information within 160ms so as to determine the time domain position of the sending moment of the S-SSB in 10240 period. For example, SL-offset indicator sync (time domain offset of the direct link) is included in the pre-configuration information. Thus, the Subframe corresponds to (SFN + Subframe Number) mod160 ═ SL-offsetiindicating syncs or (10 DFN + Subframe Number) mod160 ═ SL-offsetiindicating syncs. Wherein, Subframe Number is the Subframe Number in MIB.

In one embodiment, when the number of the preconfigured S-SSBs on each set of synchronization resources in each transmission period is 1, the preconfigured information includes a time domain offset of S-SSB transmission in each synchronization resource.

When the sending terminal only pre-configures one S-SSB for sending in each sending period, each set of pre-configured resources only occupies one slot (slot), and at this time, the pre-configured information corresponding to the synchronization resources should include a time domain offset (offset) sent by the S-SSB, i.e., a relative position of the time domain positions of the SLSS and the PSBCH in each sending period is a fixed value, and corresponds to the S-SSB sending time domain diagram in fig. 5.

Taking the transmission cycle as 160ms, the synchronization resource for transmission as resource1, 15k subcarrier u being 0, the cycle indicator indicated by the transmitting terminal is DFN or SFN high 6 bits is 000010 being 2, the synchronization resource indicator 0, the receiving terminal determines the synchronization resource1, and the offset of the acquisition resource1 in combination with the preconfigured information is 91 slots, it can be determined that the time domain position where the S-SSB transmitted by the transmitting terminal is located is:

DFN or SFN 2 × 16+ [91/(10 × 2^ u) ] -32 +9 ═ 41;

slot number 91mod (10 × 2^ u) 1.

Wherein u is related to the subcarrier spacing, 15 x 2 u, and when the subcarrier spacing is 15k, u is 0; when the subcarrier spacing is 30k, u is 1; when the subcarrier interval is 60k, u is 2; (ii) a When the subcarrier spacing is 120k, u is 3.

In one embodiment, when the number of the preconfigured S-SSBs on each group of synchronization resources in each sending period is greater than 1, each S-SSB has a number according to the time domain sequence label; the method further comprises the following steps: receiving the serial numbers of the S-SSBs, wherein the preconfigured information comprises the corresponding relation between the S-SSBs of each serial number and the time domain offset of the S-SSBs on the synchronous resources; the determining, according to the synchronization resource indicator and the pre-configuration information, an offset of a synchronization resource used by the S-SSB in a sending cycle in which the S-SSB is located, from the preset configuration information, to obtain the offset of the S-SSB in a sending cycle includes: the preset configuration information comprises a plurality of sending rules of the S-SSB in each sending period, the offset of the S-SSB in each sending period is determined according to the sending rules and the serial number of the S-SSB, and the synchronous resources used by each S-SSB are determined according to the synchronous resource indicator; and determining the offset of each S-SSB in the sending period of the S-SSB according to the serial number of the S-SSB and preset configuration information.

Specifically, when the sending terminal is preconfigured with 2 or more than 2S-SSBs for sending in each sending period, the sending terminal also sends the serial number of the S-SSB to the receiving terminal, and the receiving terminal calculates the corresponding slot serial number according to the serial number of the S-SSB and the preconfigured information. At this time, the preconfigured information includes: in each set of synchronization resources, the corresponding relationship between the S-SSB of each number included in each transmission period and the time domain offset may correspond to the S-SSB layout method described above. For example, if a localized placement method is used, the pre-configuration information may include an offset in the transmission period of the time window for transmitting the S-SSBs in each set of synchronization resources, and a time interval between each numbered S-SSB in the time window. If a distributed layout method is used, the pre-configuration information may include the relative offset of each number of S-SSBs in each group of synchronization resources per transmission period.

With reference to fig. 6 and fig. 7, the time offsets of 4S-SSBs in the combined preconfigured information acquisition resource1 by the receiving terminal are {20, 21, 22, 23} slots (this corresponds to localized data transmission), and the offset corresponding to S-SSB number 1 is determined to be 21 slots, and the time domain position where the S-SSB from the sending terminal is received by the receiving terminal is further determined to be (taking 15k subcarriers as an example):

DFN or SFN 2 × 16+ [21/(10 × 2^ u) ] -32 +2 ═ 34;

slot number 21mod (10 × 2^ u) 1.

If the scheme disclosed by the embodiment of the application is not adopted, the time domain position indication sent by the S-SSB needs 10-bit DFN or SFN and a plurality of S-SSB numbers; if the scheme disclosed in the embodiment of the present application is adopted, the time domain position indication sent by the S-SSB needs to be as follows: high 6 bits of DFN or SFN, 1 or 2 bits synchronization resource indicator and several bits of S-SSB number. It can be seen that the S-SSB numbering indication is the same in both schemes, optimized for either DFN or SFN.

The present application further provides a device for indicating synchronization time in a direct link, please refer to fig. 9, where the device for indicating synchronization time in a direct link may include:

a period indicator determining module 902, configured to generate a period indicator according to the sending time of the S-SSB, where the period indicator is used to characterize a position of a sending period in which the sending time of the S-SSB is located in a radio frame number period.

A synchronization resource indicator determining module 904, configured to determine a synchronization resource indicator according to the synchronization resource used for sending the S-SSB.

A radio frame number indicator generating module 906, configured to generate a synchronization time indicator according to the period indicator and the synchronization resource indicator.

For more contents of the working principle and the working mode of the synchronized time indication device in the direct link, reference may be made to the related descriptions in fig. 1 to fig. 7, which are not repeated herein.

The present application further provides a synchronization device in a direct link, please refer to fig. 10, where the synchronization device in the direct link may include:

a synchronization time indicator obtaining module 10, configured to obtain a synchronization time indicator, where the synchronization time indicator includes a period indicator and a synchronization resource indicator, where the period indicator is used to characterize a position of a transmission period in a radio frame number period at a transmission time of an S-SSB, and the synchronization resource indicator is used to determine a synchronization resource used by a transmitting end to transmit the S-SSB.

A sending period position determining module 11, configured to determine, according to the period indicator, a position of a sending period in which the S-SSB is located in a radio frame number period.

An offset determining module 12, configured to determine, according to the synchronization resource indicator and the preconfigured information, an offset of a synchronization resource used by the S-SSB in a sending cycle in which the S-SSB is located;

and a sending position determining module 13, configured to calculate a position of the S-SSB according to the sending period in which the S-SSB is located and the offset.

For more contents of the working principle and the working mode of the synchronization device in the direct link, reference may be made to the related description in fig. 8, which is not repeated here.

Further, an embodiment of the present application further discloses a terminal, which includes a memory and a processor, where the memory stores computer instructions capable of being executed on the processor, and the processor executes the method technical solution in the embodiment shown in fig. 1 to 7 or 8 when executing the computer instructions. Preferably, the terminal may be a User Equipment (UE) applied to the NR V2X scenario.

Further, an embodiment of the present application also discloses a storage medium, on which computer instructions are stored, and when the computer instructions are executed, the method technical solution described in the embodiments shown in fig. 1 to fig. 7 or fig. 8 is executed. Preferably, the storage medium may include a computer-readable storage medium such as a non-volatile (non-volatile) memory or a non-transitory (non-transient) memory. The storage medium may include ROM, RAM, magnetic or optical disks, etc.

In this embodiment of the present application, the Core Network may be an evolved packet Core (EPC for short), a 5G Core Network (5G Core Network), or may be a novel Core Network in a future communication system. The 5G Core Network is composed of a set of devices, and implements Access and Mobility Management functions (AMF) of functions such as Mobility Management, User Plane Functions (UPF) providing functions such as packet routing and forwarding and qos (quality of service) Management, Session Management Functions (SMF) providing functions such as Session Management, IP address allocation and Management, and the like. The EPC may be composed of an MME providing functions such as mobility management, Gateway selection, etc., a Serving Gateway (S-GW) providing functions such as packet forwarding, etc., and a PDN Gateway (P-GW) providing functions such as terminal address allocation, rate control, etc.

A Base Station (BS) in the embodiment of the present application, which may also be referred to as a base station device, is a device deployed in a Radio Access Network (RAN) to provide a wireless communication function. For example, a device providing a base station function in a 2G network includes a Base Transceiver Station (BTS), a device providing a base station function in a 3G network includes a node b (nodeb), apparatuses for providing a base station function in a 4G network include evolved node bs (enbs), which, in a Wireless Local Area Network (WLAN), the devices providing the base station function are an Access Point (AP), a device gNB providing the base station function in a New Radio (NR) of 5G, and a node B (ng-eNB) continuing to evolve, the gNB and the terminal communicate with each other by adopting an NR (NR) technology, the ng-eNB and the terminal communicate with each other by adopting an E-UTRA (evolved Universal Terrestrial Radio Access) technology, and both the gNB and the ng-eNB can be connected to a 5G core network. The base station in the embodiment of the present application also includes a device and the like that provide a function of the base station in a future new communication system.

The network on the network side in the embodiment of the present application refers to a communication network providing communication services for a terminal, and includes a base station of a radio access network, a base station controller of the radio access network, and a device on the core network side.

Definitions or descriptions of commonly used words:

a terminal in this embodiment may refer to various forms of User Equipment (UE), an access terminal, a subscriber unit, a subscriber station, a mobile station (mobile station, MS), a remote station, a remote terminal, a mobile device, a user terminal, a terminal device (terminal equipment), a wireless communication device, a user agent, or a user equipment. The terminal device may also be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with a Wireless communication function, a computing device or other processing devices connected to a Wireless modem, a vehicle-mounted device, a wearable device, a terminal device in a future 5G Network or a terminal device in a future evolved Public Land Mobile Network (PLMN), and the like, which is not limited in this embodiment.

In the embodiments of the present application, a unidirectional communication link from an access network to a terminal is defined as a downlink, data transmitted on the downlink is downlink data, and a transmission direction of the downlink data is referred to as a downlink direction; the unidirectional communication link from the terminal to the access network is an uplink, the data transmitted on the uplink is uplink data, and the transmission direction of the uplink data is referred to as an uplink direction.

It should be understood that the term "and or" is used herein to describe an association that describes an associated object, meaning that there may be three relationships, for example, a and or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "or" herein indicates that the former and latter related objects are in an "or" relationship.

"plurality" appearing in the embodiments of the present application means two or more.

The descriptions of the first, second, etc. appearing in the embodiments of the present application are for illustrative purposes and for distinguishing the objects of description, and do not indicate any particular limitation on the number of devices in the embodiments of the present application, and do not constitute any limitation on the embodiments of the present application.

"connect" in the embodiments of the present application refers to various connection manners, such as direct connection or indirect connection, to implement communication between devices, which is not limited in this embodiment of the present application.

It should be understood that, in the embodiment of the present application, the processor may be a Central Processing Unit (CPU), and the processor may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. 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 in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The nonvolatile 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 and not limitation, many forms of Random Access Memory (RAM) are available, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (dddram), enhanced SDRAM (enhanced SDRAM), synchronous DRAM (SLDRAM), Synchronous Link DRAM (SLDRAM), and direct bus RAM (DR RAM).

The above embodiments may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, the above-described embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product comprises one or more computer instructions or computer programs. The procedures or functions according to the embodiments of the present application are wholly or partially generated when the computer instructions or the computer program are loaded or executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, 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 transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire or wirelessly. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains one or more collections of available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. The semiconductor medium may be a solid state disk.

It should be understood that, in the various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

In the several embodiments provided in the present application, it should be understood that the disclosed method, apparatus and system may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative; for example, the division of the unit is only a logic function division, and there may be another division manner in actual implementation; for example, various elements or components may be combined or may be integrated into another system, or some features may be omitted, or not implemented. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may be physically included alone, or two or more units may be integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

The integrated unit implemented in the form of a software functional unit may be stored in a computer readable storage medium. The software functional unit is stored in a storage medium and includes several instructions to enable a terminal (which may be a personal computer, a server, or a network device) to perform some steps of the methods described in the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

Although the present application is disclosed above, the present application is not limited thereto. Various changes and modifications can be easily made by those skilled in the art without departing from the spirit and scope of the present application, and it is intended to cover various combinations of functions, implementation steps, software and hardware, which are described above, and embodiments of the present application.

Claims

1. A method for indicating synchronization time in a direct connection link, the method comprising:

generating a period indicator according to the sending time of the S-SSB, wherein the period indicator is used for representing the position of the sending period in which the sending time of the S-SSB is located in a radio frame number period, each radio frame period can be divided into a plurality of sending periods, and the period indicator is generated according to the label of the sending period in which the sending time of the S-SSB to be sent is located;

determining a synchronization resource indicator according to synchronization resources used for transmitting the S-SSB;

and generating a synchronization time indicator according to the period indicator and the synchronization resource indicator.

2. The method of claim 1Method, characterized in that the period indicator occupies N1 bits, wherein,

is the rounding up of the logarithm.

3. The method of claim 2, wherein when X is 10240ms and Y is 160ms, N1 is 6.

4. The method of claim 1, wherein the synchronization resource indicator occupies N2 bits, wherein,

5. The method of claim 4, wherein when Z is 2, N2 is 1; when Z is 3 or 4, N2 is 2.

6. The method of claim 1, further comprising:

and transmitting the synchronization time indicator in a PSBCH (pseudo-broadcast channel) in whole or in part.

7. The method of claim 6, wherein if the number of S-SSBs preconfigured on each set of synchronization resources in each transmission period is greater than 1;

sending a number of the S-SSB, the number being used to determine a time offset of the S-SSB on synchronization resources within the sending period.

8. A method of synchronization in a direct connection link, the method comprising:

acquiring a synchronous time indicator, wherein the synchronous time indicator comprises a period indicator and a synchronous resource indicator, each radio frame period can be divided into a plurality of sending periods, the period indicator is generated according to the label of the sending period where the sending time of the S-SSB to be sent is located, the period indicator is used for representing the position of the sending period where the sending time of the S-SSB is located in the radio frame number period, and the synchronous resource indicator is used for determining the synchronous resource used by the sending end for sending the S-SSB;

determining the sending period of the S-SSB according to the period indicator;

determining the offset of the synchronization resource used by the S-SSB in the sending cycle of the S-SSB according to the synchronization resource indicator and the pre-configuration information;

and calculating the position of the S-SSB according to the sending period of the S-SSB and the offset.

9. The method of claim 8, wherein the preconfiguration information comprises a time domain offset of S-SSB transmission in each synchronization resource when the number of preconfigured S-SSBs on each set of synchronization resources in each transmission period is 1.

10. The method of claim 8, wherein each S-SSB has a number when the number of S-SSBs preconfigured on each set of synchronization resources in each transmission cycle is greater than 1;

the method further comprises the following steps:

receiving the serial numbers of the S-SSBs, wherein the preconfigured information comprises the corresponding relation between the S-SSBs of each serial number and the time domain offset of the S-SSBs on the synchronous resources;

the determining, according to the synchronization resource indicator and the preconfigured information, an offset of a synchronization resource used by the S-SSB in a transmission cycle in which the S-SSB is located includes:

determining the synchronous resources used by each S-SSB according to the synchronous resource indicator;

and determining the offset of each S-SSB in the sending period of the S-SSB according to the serial number of the S-SSB and preset configuration information.

11. An apparatus for synchronized time indication in a direct link, the apparatus comprising:

a period indicator determining module, configured to generate a period indicator according to a sending time of the S-SSB, where the period indicator is used to represent a position of a sending period in which the sending time of the S-SSB is located in a radio frame number period, where each radio frame period may be divided into multiple sending periods, and the period indicator is generated according to a label of the sending period in which the sending time of the S-SSB to be sent is located;

a synchronization resource indicator determining module, configured to determine a synchronization resource indicator according to a synchronization resource used for sending the S-SSB;

and the wireless frame number indicator generating module is used for generating a synchronous time indicator according to the period indicator and the synchronous resource indicator.

12. A synchronization apparatus in a direct link, the apparatus comprising:

a synchronization time indicator obtaining module, configured to obtain a synchronization time indicator, where the synchronization time indicator includes a period indicator and a synchronization resource indicator, each radio frame period may be divided into multiple transmission periods, and the period indicator is generated according to a label of a transmission period in which a transmission time of an S-SSB to be transmitted is located, where the period indicator is used to represent a position of the transmission period in which the transmission time of the S-SSB is located in the radio frame number period, and the synchronization resource indicator is used to determine a synchronization resource used by a transmitting end to transmit the S-SSB;

a sending cycle position determining module, configured to determine, according to the cycle indicator, a position of a sending cycle in which the S-SSB is located in a radio frame number cycle;

an offset determining module, configured to determine, according to the synchronization resource indicator and preconfigured information, an offset of a synchronization resource used by the S-SSB in a sending cycle in which the S-SSB is located;

and the sending position determining module is used for calculating the position of the S-SSB according to the sending period of the S-SSB and the offset.

13. A user terminal comprising a memory and a processor, the memory having stored thereon computer instructions executable on the processor, wherein the processor, when executing the computer instructions, performs the steps of the method of any one of claims 1 to 7 or any one of claims 8 to 10.

14. A storage medium having stored thereon computer instructions operable to perform the steps of the method of any one of claims 1 to 7, or 8 to 10.