CN117812689A

CN117812689A - Method and device for transmitting side-link synchronous signal block

Info

Publication number: CN117812689A
Application number: CN202310404254.9A
Authority: CN
Inventors: 易凤; 苏宏家; 向铮铮; 齐鸿
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-09-30
Filing date: 2023-04-07
Publication date: 2024-04-02
Also published as: WO2024067522A1; WO2024067522A9

Abstract

The application provides a method and a device for transmitting a side-link synchronous signal block, which are applicable to the fields of V2X, intelligent driving, internet of vehicles, auxiliary driving, automatic driving and the like, wherein the method comprises the following steps: the method comprises the steps that a first terminal device fails to send the side-link synchronous signal blocks in a first time unit in N time units, or the number of time units in which the first terminal device fails to send the side-link synchronous signal blocks in the N time units is larger than a first threshold value, and the first terminal device sends the side-link synchronous signal blocks to a second terminal device in a second time unit; the second time unit is a time unit other than the N time units. By the method provided by the application, the first terminal equipment transmits the side uplink synchronous signal block in the time units except for N time units, so that the transmission opportunity of the side uplink synchronous signal block is increased, and the synchronous performance of the system is improved.

Description

Method and device for transmitting side-link synchronous signal block

The present application claims priority from chinese patent office, application number 202211216273.0, application name "a method and apparatus for transmitting side-uplink synchronization signal block", filed on month 30 of 2022, the entire contents of which are incorporated herein by reference.

Technical Field

The present disclosure relates to the field of communications technologies, and in particular, to a method and an apparatus for transmitting a side uplink synchronization signal block.

Background

In a wireless communication system, frequency bands used by communication devices can be divided into licensed (licensed) spectrum and unlicensed (unlicensed) spectrum. In licensed spectrum, the communication device uses spectrum resources based on the scheduling of the central node. In the unlicensed band, a communication device contends for a channel through a channel access mechanism (e.g., listen-before-talk (LBT) mechanism). An important evolution direction of the Sidelink (SL) is to enable SL communication of unlicensed spectrum in local space, which may be referred to collectively as SL unlicensed (SL-U) communication.

In wireless communication, it is necessary to maintain time synchronization between communication apparatuses before communication is performed. For example, in an NR SL system, a terminal device can broadcast a side-uplink synchronization signal block (sidelink synchronization signal block, S-SSB) and the terminal device receiving the S-SSB can complete time synchronization. However, in the unlicensed spectrum, the terminal device needs to compete for the channel in the LBT manner, and the S-SSB can be sent only after the LBT passes, which results in that the S-SSB cannot be sent in time, so that the devices cannot be synchronized in time, and the communication performance between the devices is reduced.

Disclosure of Invention

The application provides a method and a device for transmitting side uplink synchronous signal blocks, which are used for increasing transmission opportunities for transmitting S-SSB in unlicensed spectrum and improving communication performance.

In a first aspect, the present application provides a method for transmitting a side-link synchronization signal block, where the method is applicable to a scenario of unlicensed spectrum communication such as V2X and SL-U. The execution body of the method is a terminal device or a module in a terminal device, and the first terminal device is taken as an execution body for example. The method comprises the following steps: the first terminal equipment determines N time units in a first period according to the first configuration information, wherein N is an integer greater than 0, and the N time units are candidate time units for transmitting side uplink synchronous signal blocks; the first terminal equipment fails to send the side-link synchronous signal block in a first time unit in the N time units, or the number of time units in which the first terminal equipment fails to send the side-link synchronous signal block in the N time units is larger than a first threshold value, and the first terminal equipment sends the side-link synchronous signal block to a second terminal equipment in a second time unit; the second time unit is located in the first period and is a time unit other than the N time units.

By the method provided by the application, the first terminal equipment transmits the side uplink synchronous signal block in the time units except for N time units, so that the transmission opportunity of the side uplink synchronous signal block is increased, and the synchronous performance of the system is improved.

In a second aspect, the present application provides a method for transmitting a side-uplink synchronization signal block, where the method is applicable to a scenario of unlicensed spectrum communication such as V2X and SL-U. The execution body of the method is a terminal device or a module in a terminal device, and the second terminal device is taken as an execution body for example. The method comprises the following steps: the second terminal equipment determines N time units in a first period according to the first configuration information, wherein N is an integer greater than 0, and the N time units are candidate time units for transmitting side uplink synchronous signal blocks; the second terminal device fails to receive the side-link synchronization signal block in a first time unit of the N time units, or the number of time units in which the second terminal device fails to receive the side-link synchronization signal block in the N time units is greater than a first threshold, and the second terminal device receives the side-link synchronization signal block in a second time unit; the second time unit is located in the first period and is a time unit other than the N time units.

With reference to the first aspect, in one possible implementation manner, the method further includes:

the first terminal device determines M time units according to the first configuration information, where M is an integer greater than 0, the M time units are candidate time units for transmitting the side uplink synchronization signal block, the second time unit belongs to the M time units, and the M time units are time units other than the N time units in the first period.

the first terminal device sends first side link control information to the second terminal device, wherein the first side link control information is used for determining the second time unit.

With reference to the first aspect or the second aspect, in a possible implementation manner, the first side uplink control information is further used to determine one or more of the following: the location of the second time cell; the location of the set of sub-channels or interleaved resource blocks occupied by the side-uplink synchronization signal block in the second time unit.

With reference to the first aspect or the second aspect, in a possible implementation manner, a first duration is spaced between the second time unit and a first time unit or a last time unit of the N time units.

With reference to the first aspect or the second aspect, in one possible implementation manner, the first duration is a duration configured by the network device; or, the first duration is a preconfigured duration; or, the first duration is a duration specified by a protocol.

With reference to the first aspect or the second aspect, in a possible implementation manner, the first time unit is separated from the second time unit by a second duration.

With reference to the first aspect or the second aspect, in a possible implementation manner, the second duration is a duration configured by the network device; or, the second duration is a preconfigured duration; or, the second duration is a duration specified by a protocol.

With reference to the first aspect or the second aspect, in one possible implementation manner, an offset value between a starting point of a frequency domain resource occupied by the side uplink synchronization signal block and a starting point of a frequency domain resource occupied by the first terminal device is a first frequency domain offset value; the first frequency domain offset value is preset, or the first frequency domain offset value is determined for the first terminal device, or the first frequency domain offset value is configured for a network device.

With reference to the second aspect, in a possible implementation manner, the method further includes:

The second terminal device determines M time units according to the first configuration information, where M is an integer greater than 0, the M time units are candidate time units for transmitting the side uplink synchronization signal block, the second time unit belongs to the M time units, and the M time units are time units other than the N time units in the first period.

the second terminal device receives first side-link control information from the first terminal device, the first side-link control information being used to determine the second time unit.

With reference to the first aspect or the second aspect, in a possible implementation manner, the second time unit includes first side line information, a third time unit before the second time unit includes cyclic prefix extension CPE, the CPE and the first side line information come from the first terminal device, the third time unit and the second time unit are adjacent in a time domain, and a duration of the CPE is a first transmission duration.

With reference to the first aspect or the second aspect, in a possible implementation manner, the CPE further includes second sidestream information, where a gap between the second sidestream information and the CPE is smaller than the first gap; the first gap is predefined, preconfigured, or network configured; the duration of the first gap takes on a value of 16 microseconds or 25 microseconds.

With reference to the first aspect or the second aspect, in one possible implementation manner, the CPE includes a first type CPE and a second type CPE, where the first type CPE is a CPE that sends a side line synchronization signal by a first terminal device, the second type CPE is a CPE that sends a side line shared channel by the first terminal device, and a duration of the first type CPE is different from a duration of the second type CPE.

With reference to the first aspect or the second aspect, in one possible implementation manner, a duration of the first type of CPE is greater than a duration of the second type of CPE.

With reference to the first aspect or the second aspect, in a possible implementation manner, the method further includes:

the first terminal equipment acquires first indication information; the first indication information is used for indicating that the duration of the first type CPE is longer than the duration of the second type CPE; or the CPE time length of the transmission side line synchronous signal is smaller than the time length of the CPE of the transmission side line shared channel of the first terminal; the first indication information is preconfigured or network configured.

In a third aspect, the present application provides a communication method, which is suitable for a scenario of unlicensed spectrum communication such as V2X and SL-U. The execution body of the method is a terminal device or a module in a terminal device, and the first terminal device is taken as an execution body for example. The method comprises the following steps: the first terminal equipment generates a link synchronization signal block; the first terminal equipment sends a side uplink synchronous signal block to the second terminal equipment; wherein the synchronization signal block includes a physical broadcast side uplink channel and a side uplink synchronization sequence.

In a fourth aspect, the present application provides a communication method, which is suitable for a scenario of unlicensed spectrum communication such as V2X and SL-U. The execution body of the method is a terminal device or a module in a terminal device, and the second terminal device is taken as an execution body for example. The method comprises the following steps: the second terminal equipment receives the side uplink synchronous signal block from the first terminal equipment; the second terminal equipment performs synchronization according to the side uplink synchronization signal block; wherein the synchronization signal block includes a physical broadcast side uplink channel and a side uplink synchronization sequence.

With reference to the third aspect or the fourth aspect, one possible implementation manner of the physical broadcast side uplink channel occupies a plurality of continuous resource blocks or a plurality of discontinuous resource blocks; the side-uplink synchronization sequence occupies a plurality of consecutive resource blocks or the side-uplink synchronization sequence occupies a plurality of non-consecutive resource blocks.

With reference to the third aspect or the fourth aspect, in a possible implementation manner, when a subcarrier spacing of the channel occupied by the first terminal device is smaller than 60kHz, a resource block occupied by the physical broadcast side uplink channel is located in a first frequency domain resource and/or a second frequency domain resource.

With reference to the third aspect or the fourth aspect, in one possible implementation manner, the first frequency domain resource is located on a subchannel or an interleaved resource block set, the second frequency domain resource is a resource block, and the first frequency domain resource and the second frequency domain resource are adjacent in position.

With reference to the third aspect or the fourth aspect, in one possible implementation manner, when a resource block occupied by the physical broadcast side uplink channel is located in 2 interlaces, the 2 interlaces are adjacent in position.

With reference to the third aspect or the fourth aspect, in one possible implementation manner, when a resource block occupied by the physical broadcast side uplink channel is located in 2 sub-channels, the 2 sub-channels are located adjacent to each other.

With reference to the third aspect or the fourth aspect, a possible implementation manner of the present invention is that Z resource blocks occupied by the physical broadcast side uplink channel, Z is less than or equal to 11, and Z is configured by a network, or is preconfigured, or is agreed by a protocol.

With reference to the third aspect or the fourth aspect, in one possible implementation manner, when a subcarrier spacing of the channel is equal to 15kHz, a number of resource blocks occupied by the side uplink synchronization sequence is equal to 12.

With reference to the third aspect or the fourth aspect, in one possible implementation manner, when a subcarrier spacing of the channel occupied by the first terminal device is equal to 60kHz, the physical broadcast side uplink channel occupies discontinuous 11 resource blocks, 1 resource block is spaced between two adjacent resource blocks in the 11 resource blocks, or the physical broadcast side uplink channel occupies at least continuous 23 resource blocks; the side-uplink synchronization sequence occupies 11 consecutive resource blocks.

With reference to the third aspect or the fourth aspect, in a possible implementation manner, when the physical broadcast side uplink channel occupies 11 discontinuous resource blocks, the method further includes:

the first terminal device sends bit bitmap indication information to the second terminal device, wherein the bit bitmap indication information is used for indicating positions of 11 resource blocks occupied by the physical broadcast side uplink channel in the channel.

With reference to the third aspect or the fourth aspect, a possible implementation manner, the method further includes:

the first terminal equipment sends offset value indication information to the second terminal equipment, wherein the offset value indication information is used for indicating a frequency domain offset value, and the frequency domain offset value is an offset value between a starting point of a frequency domain resource of the side uplink synchronous sequence and a starting point of a frequency domain resource of the channel occupied by the first terminal equipment.

In a fifth aspect, the present application also provides a communication device having any of the methods provided in any of the first to fourth aspects. The communication device may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the functions described above.

In one possible implementation, the communication device includes: a processor configured to support the communication apparatus to perform the corresponding functions of the network device in the method shown above. The communication device may also include a memory, which may be coupled to the processor, that holds the program instructions and data necessary for the communication device. Optionally, the communication device further comprises an interface circuit for supporting communication between the communication device and a terminal equipment or the like.

In one possible implementation manner, the communication device includes corresponding functional modules, each for implementing the steps in the above method. The functions may be realized by hardware, or may be realized by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

In a possible implementation manner, the communication apparatus includes a processing unit and a sending unit in a structure, where the processing unit and the sending unit may perform corresponding functions in the foregoing method examples, and specific reference is made to descriptions in the methods provided in any one of the first aspect to the fourth aspect, which are not described herein in detail.

In a sixth aspect, there is provided a communication device comprising a processor and interface circuitry for receiving signals from or transmitting signals to the processor from or to other communication devices than the communication device, the processor being operable to implement the method of any of the preceding first to fourth aspects, and any possible implementation of any of the preceding aspects, by logic circuitry or execution of code instructions.

In a seventh aspect, there is provided a communication device comprising a processor and interface circuitry for receiving signals from or transmitting signals to the processor from or transmitting signals to other communication devices than the communication device, the processor being operable to implement the functional modules of the method of any of the preceding first to fourth aspects, and any possible implementation of any of the preceding first to fourth aspects, by logic circuitry or execution of code instructions.

In an eighth aspect, there is provided a computer readable storage medium having stored therein a computer program or instructions which, when executed by a processor, implement the method of any one of the preceding first to fourth aspects, and any possible implementation of any one of the preceding aspects.

A ninth aspect provides a computer program product storing instructions which, when executed by a processor, implement the method of any of the preceding first to fourth aspects, and any possible implementation of any of the preceding aspects.

In a tenth aspect, a chip is provided, the chip comprising a processor and may further comprise a memory for implementing the method of any of the foregoing first to fourth aspects and any possible implementation of any of the foregoing aspects. The chip may be formed from a chip or may include a chip and other discrete devices.

Drawings

Fig. 1 (a) to fig. 1 (c) are schematic diagrams of a network architecture according to an embodiment of the present application;

fig. 2 is a schematic diagram of a channel structure according to an embodiment of the present application;

fig. 3 is a schematic diagram of a channel structure according to an embodiment of the present application;

fig. 4 is a schematic diagram of channel division provided in an embodiment of the present application;

fig. 5 is a schematic diagram of channel division provided in an embodiment of the present application;

fig. 6 is a schematic diagram of a transmission cycle of a side uplink synchronization signal block according to an embodiment of the present application;

fig. 7 is a schematic flow chart of a method for transmitting a side uplink synchronization signal block according to an embodiment of the present application;

fig. 8 (a) to fig. 8 (c) are schematic diagrams of sidestream information transmission provided in the embodiments of the present application;

fig. 8 (d) is a schematic diagram of a transmission of a side uplink synchronization signal block according to an embodiment of the present application;

fig. 9 is a schematic diagram of transmission of a side uplink synchronization signal block according to an embodiment of the present application;

fig. 10 is a schematic diagram of transmission of a side uplink synchronization signal block according to an embodiment of the present application;

fig. 11 is a schematic diagram of transmission of a side uplink synchronization signal block according to an embodiment of the present application;

fig. 12 is a schematic diagram of transmission of a side uplink synchronization signal block according to an embodiment of the present application;

Fig. 13 is a flowchart of a method for transmitting a side uplink synchronization signal block according to an embodiment of the present application;

fig. 14 is a schematic diagram of a side uplink synchronization signal block structure according to an embodiment of the present application;

fig. 15 is a schematic diagram of a side uplink synchronization signal block structure according to an embodiment of the present application;

fig. 16 is a schematic diagram of a side uplink synchronization signal block structure according to an embodiment of the present application;

fig. 17 is a schematic diagram of a side uplink synchronization signal block structure according to an embodiment of the present application;

fig. 18 is a schematic diagram of a side uplink synchronization signal block structure according to an embodiment of the present application;

fig. 19 is a schematic diagram of a side uplink synchronization signal block structure according to an embodiment of the present application;

fig. 20 is a schematic diagram of a side uplink synchronization signal block structure according to an embodiment of the present application;

fig. 21 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 22 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

Embodiments of the present application are described in detail below with reference to the accompanying drawings.

The communication method provided by the embodiments of the present application can be applied to a fifth generation (5th generation,5G) communication system, for example, a 5G New Radio (NR), or to various communication systems in the future, for example, a sixth generation (6th generation,6G) communication system. Specifically, the communication method provided by the embodiment of the application can be applied to the fields of vehicle-to-anything (vehicle to everything, V2X) communication, vehicle networking, automatic driving, auxiliary driving and the like.

The method and the device provided in the embodiments of the present application are based on the same or similar technical ideas, and because the principles of solving the problems by the method and the device are similar, the implementation of the device and the method can be referred to each other, and the repetition is not repeated.

In the following, some terms in the embodiments of the present application are explained first to facilitate understanding by those skilled in the art.

The network device involved in the embodiment of the present application may be a device in a wireless network. For example, the network device may be a device deployed in a radio access network to provide wireless communication functionality for terminal devices. For example, the network device may be a radio access network (radio access network, RAN) node, also referred to as access network device, that accesses the terminal device to the wireless network.

Network devices include, but are not limited to: an evolved Node B (eNB), a radio network controller (radio network controller, RNC), a Node B (Node B, NB), a base station controller (base station controller, BSC), a base transceiver station (base transceiver station, BTS), a home base station (home evolved NodeB, or home Node B, HNB, for example), a baseband unit (BBU), an Access Point (AP) in a wireless fidelity (wireless fidelity, WIFI) system, a wireless relay Node, a wireless backhaul Node, a transmission point (transmission point, TP), or a transmission reception point (transmission and reception point, TRP), etc., may also be a network device in a 5G mobile communication system. For example, next generation base stations (gNB) in NR systems, transmission reception points (transmission reception point, TRP), TP; or one or a group (including a plurality of antenna panels) of base stations in a 5G mobile communication system; alternatively, the network device may also be a network node constituting a gNB or a transmission point. Such as a BBU, or a Distributed Unit (DU), etc.

In some deployments, the gNB may include a Centralized Unit (CU) and DUs. The gNB may also include an active antenna unit (active antenna unit, AAU). The CU implements part of the functionality of the gNB and the DU implements part of the functionality of the gNB. For example, the CU is responsible for handling non-real time protocols and services, implementing the functions of the radio resource control (radio resource control, RRC), packet data convergence layer protocol (packet data convergence protocol, PDCP) layer. The DUs are responsible for handling physical layer protocols and real-time services, implementing the functions of the radio link control (radio link control, RLC), medium access control (media access control, MAC) and Physical (PHY) layers. The AAU realizes part of physical layer processing function, radio frequency processing and related functions of the active antenna. The information of the RRC layer may eventually become information of the PHY layer or may be converted from the information of the PHY layer. Under this architecture, higher layer signaling (e.g., RRC layer signaling) may also be considered to be sent by DUs, or by DUs and AAUs. It is understood that the network device may be a device comprising one or more of a CU node, a DU node, an AAU node. In addition, the CU may be divided into network devices in the RAN, or may be divided into network devices in a Core Network (CN), which is not limited in this application.

The terminal device involved in the embodiment of the present application may be a wireless terminal device capable of receiving the network device scheduling and indication information. The terminal device may be a device that provides voice and/or data connectivity to a user, or a handheld device with wireless connectivity, or other processing device connected to a wireless modem.

A terminal device, also called User Equipment (UE), mobile Station (MS), mobile Terminal (MT), etc. A terminal device is a device that includes wireless communication functionality (providing voice/data connectivity to a user). For example, a handheld device having a wireless connection function, or an in-vehicle device, an in-vehicle module, or the like. Currently, examples of some terminal devices are: a mobile phone, a tablet, a notebook, a palm, a mobile internet device (mobile internet device, MID), a wearable device, a Virtual Reality (VR) device, an augmented reality (augmented reality, AR) device, a wireless terminal in industrial control (industrial control), a wireless terminal in the internet of vehicles, a wireless terminal in the unmanned (self driving), a wireless terminal in teleoperation (remote medical surgery), a wireless terminal in the smart grid (smart grid), a wireless terminal in transportation security (transportation safety), a wireless terminal in smart city (smart city), or a wireless terminal in smart home (smart home), a device-to-device communication (device-to-device), D2D) terminal devices, car and anything (vehicle to everything, V2X) communication terminal devices, intelligent vehicles, car systems (or on-board transmission units) (T-boxes), machine-to-machine/machine-type communication (M2M/MTC) terminal devices, internet of things (internet of things, ioT) terminal devices, and the like. For example, the terminal device may be an in-vehicle device, a whole vehicle device, an in-vehicle module, a vehicle, an On Board Unit (OBU), a roadside unit (RSU), a T-box, a chip or a System On Chip (SOC), or the like, which may be mounted in the vehicle, the OBU, the RSU, or the T-box. The wireless terminal in the industrial control can be a camera, a robot and the like. The wireless terminal in the smart home can be a television, an air conditioner, a floor sweeping machine, a sound box, a set top box and the like.

The present application is applicable to scenarios supporting side-link communications, which may also be referred to as side-links, and to communications scenarios with and without network coverage, both referred to herein as side-links. Fig. 1 (a) to 1 (c) are schematic diagrams of a network architecture suitable for the present application. In fig. 1 (a), both terminal device a and terminal device B are within signal coverage of the network device; in fig. 1 (B), terminal device a is within the signal coverage of the network device, but terminal device B is outside the signal coverage of the network device. In fig. 1 (c), both terminal device a and terminal device B are outside the signal coverage of the network device.

Between the terminal device a and the terminal device B in fig. 1 (a) and fig. 1 (B), communication may be performed through a resource usage-side uplink scheduled by the network device, where the resource may be an authorized resource or an authorized frequency band; the terminal equipment can also perform resource self-selection between the terminal equipment A and the terminal equipment B, namely, select the resource used for side-link communication from a resource pool, wherein the resource is an unlicensed resource or an unlicensed frequency band.

Both terminal device a and terminal device B in fig. 1 (c) are outside the signal coverage of the network device, and therefore can only communicate via the side-link in a resource-free manner.

The following explains the related technical features related to the embodiments of the present application. It should be noted that these explanations are for easier understanding of the embodiments of the present application, and should not be construed as limiting the scope of protection claimed in the present application.

Communication over unlicensed spectrum:

in a wireless communication system, spectrum resources can be divided into licensed spectrum and unlicensed spectrum. Licensed spectrum can only be used by a particular operator somewhere, while unlicensed spectrum can be used by any operator, being a shared spectrum resource.

Unlicensed spectrum usage may include wireless fidelity (wireless fidelity, wi-Fi), bluetooth, wireless personal area network (Zigbee), and the like. In addition, cellular mobile communication technologies (such as 5G communication technology) have also been under study to introduce unlicensed spectrum, such as NR-U technology.

Communications over unlicensed spectrum may be required to adhere to certain regulations, such as listen-before-talk (LBT) based channel access and occupied channel bandwidth (occupied channel bandwidth, OCB) requirements, for ensuring access fairness among various devices operating over unlicensed spectrum.

LBT-based channel access:

Channel access based on LBT generally employs energy-based detection and signal type detection, such as NR-U technology employs energy-based detection, while Wi-Fi technology employs two combined detection methods. Wherein, a detection threshold (energy detection threshold) of energy is set based on the detection of energy, when the energy detected by the communication device (terminal device or network device) exceeds the detection threshold, the communication device decides that the channel is busy, and then the communication device is not allowed to access the channel; when the detected energy is lower than the detection threshold and lasts for a period of time, the communication equipment judges that the channel is idle and allows the channel to be accessed. For example, the detected energy may be a reference signal received power (reference signal received power, RSRP) and the corresponding detection threshold may be an RSRP threshold.

Taking the terminal device in NR-U technology as an example, the terminal device may employ LBT of the following types (types):

(1) type 1LBT (type 1 LBT): the terminal device or the network device using the type 1LBT needs to perform random backoff before accessing the channel for information transmission.

In particular, the terminal device may operate for a perceived time slot period (sensing slot duration, denoted as T) of an extended duration (denoted as Td) _sl ) After the interception (interception can be replaced by sensing) channel is idle, and after the counter N in the terminal equipment is zero, information transmission can be performed; wherein the perceived slot period may be 9 microseconds (mus).

(2) Type 2A LBT (type 2A LBT): a terminal device or a network device using the type 2A LBT can access a channel and transmit data after perceiving that the channel is idle for at least 25 mus.

(3) Type 2B LBT (type 2B LBT): a terminal device or a network device using the type 2B LBT can access a channel and transmit data after perceiving that the channel is idle for at least 16 mus.

(4) Type 2C LBT (type 2C LBT): the terminal device or the network device using the type 2C LBT does not need to sense a channel, and can directly access the channel and transmit data after a switching interval of at most 16 mus within the COT.

The channel access of the unlicensed band in the embodiment of the present application may use the LBT of the above type, but the embodiment of the present application does not limit the channel access of the unlicensed spectrum by using other channel access modes allowed by other national/regional laws and regulations.

Side line information:

in the embodiments of the present application, the information transmitted through the sidelink may be referred to as sidelink information. For example, the sidestream information may include sidestream control information (sidelink control information, SCI) and/or sidestream data. It will be appreciated that the sidestream information may also include other possible information, and that embodiments of the present application will be described with reference to sidestream information including SCI and/or sidestream data.

The SCI may be carried on a physical layer side control channel (physical sidelink control channel, PSCCH) and/or a physical layer side uplink shared channel (physical sidelink shared channel, PSSCH), and the side data may be carried on the PSSCH. The SCI carried by the PSCCH may be referred to as a first level SCI and the SCI carried by the pscsch may be referred to as a second level SCI.

Further, the scheduling granularity of the PSCCH or PSSCH is in a time unit and in a frequency domain is in a frequency domain unit or a plurality of consecutive frequency domain units. That is, the resources used by the terminal device for the side-link communication must be an integer multiple of the time unit in the time domain and an integer multiple of the frequency domain unit in the frequency domain. One time unit may be a slot (slot) or a mini-slot (mini-slot), which is not limited in particular, and in the embodiment of the present application, a time unit will be described as an example of a slot; the frequency domain unit may be one RB, multiple RBs, one subchannel, multiple subchannels, one interleaving resource, or multiple interleaving resources, which is not specifically limited.

OCB requirement:

the minimum OCB requirement needs to be met to occupy the channel according to national and regional regulatory requirements for using unlicensed spectrum. For example, in one implementation, the minimum OCB requirement may refer to: the occupied channel bandwidth is at least 80% of the nominal channel bandwidth, which refers to the bandwidth allocated to a single channel. Taking the example of a channel bandwidth of 20MHz, at least 16MHz of bandwidth is required to preempt the 20MHz channel.

Selection and reservation of resources:

as described above, the terminal device may autonomously select resources in the resource pool. For example, the terminal device may first select a resource from the resource pool and reserve the resource, and then send side information on the reserved resource after completing channel access.

In one example, after the terminal device selects a resource in the resource pool, the SCI may be transmitted, where the SCI is used to indicate resources (including time domain resources and frequency domain resources) of the side line information transmitted by the terminal device. After receiving the SCI of the terminal equipment, the other terminal equipment can acquire the reserved resources of the terminal equipment, and then the other terminal equipment can exclude the reserved resources of the terminal equipment when selecting the resources. The specific implementation of selecting resources from the resource pool by the terminal device can be seen in the prior art.

The resource pool (resource pool) may also be referred to as a SL resource pool. Alternatively, the resource pool may be preconfigured; for example, under the coverage of the network, the network device sends resource pool information to the terminal device in the cell through a system information block (system information block, SIB), a cell-specific (cell-specific) radio resource control (radio resource control, RRC) signaling, or a user-specific (UE-specific) RRC signaling, where the resource pool information is used to indicate the resource pool. Alternatively, the resource pool may be predefined.

In the unlicensed band, terminal devices contend for a channel by an LBT scheme before communicating. After the terminal device has successfully accessed the channel, the time allowed to occupy the channel is called the channel occupation time (channel occupancy time, COT). In SL, a pool of resources for data transmission may be preconfigured, one pool of resources may include one or more channels. In one implementation, the bandwidth size of each channel is 20MHz. When a resource pool includes a channel, the resource blocks included in the resource pool are Resource Blocks (RBs) corresponding to a set of RB in the channel. For example, as shown in fig. 2, in the unlicensed band, one channel includes an RB set and guard bandwidths at both ends, the guard bandwidths being used to ensure that signals/energy on the current channel do not interfere with adjacent channels. The frequency domain resources within the RB set are available for data transmission.

If one resource pool includes a plurality of channels, the resource pool includes a set of RBs and resource blocks of a partial guard bandwidth. For example, as shown in fig. 3, channel 1 includes RB set 1, channel 2 includes RB set 2, and then the resource pool includes RB set 1, RB set 2, and guard bandwidths between RB set 1 and RB set 2. When one terminal device succeeds in LBT on both channels and wants to send data in both RB sets, the resources available to the terminal device are not only the resources on the RB sets in both channels, but also the guard bandwidth between two adjacent RB sets.

In this application, one RB set may be divided into a plurality of subsets. In an implementation, the resource blocks in the RB set may be divided into M subsets in an interleaved manner, where each subset includes resource blocks separated by M resource blocks between two adjacent resource blocks. In this implementation, each subset may be referred to as an interlace (interlace) or a set of interlace resource blocks. Assuming that a subset is identified as M, M e {0,1, …, M-1}, and the index of the starting resource block of the channel is 0, the index of the resource block included in the channel for that subset is: { M, M+m,2M+m,3M+m, … }. For example, as shown in fig. 4, for a channel with a 15kHz subcarrier spacing, the channel includes 105 RBs, and when m=10, the subset identified as #0 in the RB set includes the following indexes of resource blocks: {0,10,20,30, … 100}, the subset identified as #1 in the RB set includes the resource blocks with the indexes: {1,11,21,31, … 101}, and the like.

In another implementation, a plurality of consecutive resource blocks in an RB set may be divided into one subset, and a resource block in one RB set may be divided into M subsets. In this implementation, the resource blocks included in the subsets are contiguous, and each subset may be referred to as a subchannel. Assuming that a subset is identified as M, M e {0,1, …, M-1}, and the index of the starting resource block of the channel is 0, the index of the resource block included in the channel for that subset is: { m, m+1, m+2, m+3, … }. For example, as shown in fig. 5, for a channel with a 15kHz subcarrier spacing, the channel includes 105 RBs, and when m=10, the subset identified as #0 in the RB set includes the following indexes of resource blocks: {0,1,2,3, … }, the subset identified as #1 in the RB set includes the resource blocks with the indexes: {11,12,13, … }, and the like.

In the present application, the terminal device may broadcast the S-SSB to other terminal devices, so that synchronization between the terminal devices is maintained. When the terminal device needs to broadcast the S-SSB, the time domain location and the frequency domain location of the transmitted S-SSB may be determined according to S-SSB configuration information in radio resource control (radio resource control, RRC) signaling or pre-configured (pre-configured) S-SSB configuration information. The RRC signaling is control information sent by the gNB or the eNB to the terminal device, and the preconfigured S-SSB configuration information is control information recorded in hardware and/or software of the terminal device. For example, for a time domain location of an S-SSB, the S-SSB configuration information includes three parameters:

representing the number of S-SSBs transmitted in a cycle;

representing a slot offset between a first S-SSB transmitted in a period and a start point of the period;

representing the time slot spacing between two adjacent S-SSBs within a period, wherein +.>Greater than 1. This value applies when there are multiple S-SSBs in the S-SSB period.

Based on the above three parameters, the terminal device can determine the time domain location of the transmitted S-SSB. Illustratively, when When the period duration is 160ms, as shown in fig. 6, the time domain position of the S-SSB transmission in one period is illustrated. For each 160ms period, the terminal device will transmit an S-SSB signal on two slots marked as shaded in the figure.

One S-SSB includes a physical side-link control channel (physical sidelink broadcast channel, PSBCH), a side-link primary synchronization signal (sidelink primary synchronization signal, S-PSS), and a side-link secondary synchronization signal S-SSS (sidelink secondary synchronization signal, S-SSS). For a slot for transmitting S-SSB, the slot length is 14 orthogonal frequency division multiplexing (orthogonal frequency division multiplexing, OFDM) symbols, with the 0 th symbol used for automatic gain control (automatic gain control, AGC); the 1 st and 2 nd symbols are used for transmitting the S-PSS. The 3 rd and 4 th symbol positions are used for transmitting S-SSS; the last symbol, the gap symbol, is blanked for a transmit-receive switch and the remaining symbols in the real slot are used for transmission of the PSBCH.

In the unlicensed frequency band, the terminal equipment needs to compete for the channel before sending the S-SSB, and the S-SSB can be sent after the competition channel is successful, if the terminal equipment fails to compete for the channel at the time slot position indicated by the configuration information, the S-SSB cannot be sent in time, so that the equipment cannot be synchronized in time, and the communication performance between the equipment is reduced. Therefore, the method can improve the transmission opportunity of the S-SSB, so that the equipment can be synchronized in time.

The network architecture and the service scenario described in the embodiments of the present application are for more clearly describing the technical solution of the embodiments of the present application, and do not constitute a limitation on the technical solution provided in the embodiments of the present application, and those skilled in the art can know that, with the evolution of the network architecture and the appearance of the new service scenario, the technical solution provided in the embodiments of the present application is also applicable to similar technical problems.

As shown in fig. 7, a flow chart of a method for transmitting a side uplink synchronization signal block according to an embodiment of the present application is provided, where the method includes:

step 701: the first terminal device determines N time units in the first period according to the first configuration information.

Where N is an integer greater than 0, and N time units are candidate time units for the transmission side uplink synchronization signal block. The first period is 160ms or other predefined, preconfigured or configured value.

In this application, the first configuration information may be RRC signaling from the network device. The first configuration information may also be information preconfigured in the terminal device, that is, by presetting the number of S-SSBs in a period, the time slot offset value between the first S-SSB transmitted in a period and the starting point of the period, the time slot interval value between two adjacent S-SSBs in a period, and other information, the specific positions of N time units in the first period may be determined, where the information is preconfigured when the terminal device leaves the factory. The time units may be time slots, or mini-slots, or subframes, or time units like time slots.

The first configuration information may indicate a period duration of the first period and may also indicate a location of each of the N time units.

In the present application, the first configuration information may further indicate a frequency domain location occupied by the side uplink synchronization signal block. For example, the first configuration information may further indicate that an offset value between a start point of a frequency domain resource occupied by the side uplink synchronization signal block and a start point of a frequency domain resource occupied by the first terminal device is the first frequency domain offset value. The first frequency domain offset value may also be configured by the network device through a separate configuration information, or the first frequency domain offset value may also be preset, or the first frequency domain offset value may be determined for the first terminal device, which is not limited in this application. The first frequency domain offset value may also be an offset value of a starting point of a frequency domain resource occupied by the side uplink synchronization signal block relative to an end point of a frequency domain resource occupied by the first terminal device, or a certain position in the middle; alternatively, the first frequency domain offset value may be a position of a certain position in the middle of the frequency domain resource occupied by the side uplink synchronization signal block relative to a start point/end point of the frequency domain resource occupied by the first terminal device, or an offset value of a certain position in the middle.

Step 702: the first terminal device fails to transmit the side uplink synchronization signal block in a first time unit of the N time units, or the number of time units in which the first terminal device fails to transmit the side uplink synchronization signal block in the N time units is greater than a first threshold, and the first terminal device transmits the side uplink synchronization signal block to the second terminal device in a second time unit.

The first threshold is preset, can be configured for the network device, and can be determined for the first terminal device. The first threshold may be an integer greater than 0. The first time unit is any time unit in the N time units.

In another implementation manner, the first terminal device succeeds in transmitting the side downlink synchronization signal block in a first time unit of the N time units, or the number of time units in which the first terminal device fails to transmit the side downlink synchronization signal block in the N time units is smaller than or equal to a first threshold, or the number of time units in which the first terminal device succeeds in transmitting the side downlink synchronization signal block in the N time units is greater than or equal to a second threshold, and the first terminal device does not transmit the side downlink synchronization signal block in the second time unit. For example, the first terminal device may send other data or signals than the side-uplink synchronization signal block, such as physical side-shared channel data, and/or physical side-shared channel data, in the second time unit.

The second threshold is preset, can be configured for the network device, and can be determined for the first terminal device. The second threshold may be an integer greater than 0.

In one implementation, the first terminal device transmits first side information on the second time unit, where the first side information is a side uplink synchronization signal block or PSSCH (side data). A third time unit may be included before the second time unit, the third time unit and the second time unit being adjacent in the time domain.

The first terminal device may also send a cyclic prefix extension (cyclic prefix extension, CPE) at a third time unit for a first transmission duration. The end position of the CPE may be the end position of the third time unit.

In one implementation, the CPE further includes second sidestream information before the CPE, where a gap between the second sidestream information and the CPE is smaller than the first gap; the first gap is predefined, preconfigured, or network configured. For example, the duration of the first gap takes on a value of 16 microseconds or 25 microseconds. The second sidestream information may be sent by the first terminal device or may be sent by another terminal device. The gap between the second sidestream information and the CPE is smaller than the first gap, which may mean that the gap between the end position of the second sidestream information and the start position of the CPE is smaller than the first gap. The gap may not be used for transmitting information or signals.

In one implementation, the CPE further includes second sidestream information before the CPE, where a gap between the second sidestream information and the CPE is greater than the second gap; the second gap is predefined, preconfigured, or network configured. For example, the duration of the first gap takes a value of 25 microseconds. The second sidestream information may be sent by the first terminal device or may be sent by another terminal device. The gap between the second sidestream information and the CPE being greater than the second gap may mean that the gap between the end position of the second sidestream information and the start position of the CPE is greater than the second gap. The gap may not be used for transmitting information or signals. In this implementation, optionally, the second gap is less than one OFDM symbol duration, the duration of OFDM being related to the subcarrier spacing.

For example, when the sidestream terminal is shared with the access channel by means of type 2B and transmits PSCCH/PSSCH in the second time unit, in the resource pool or in the SL BWP, the duration of the first gap takes a value of 25 microseconds; for example, the third terminal device sends the second sidestream information, the first terminal device sends the CPE in the third time unit, the first terminal device is shared with the access channel and sends the PSCCH/PSSCH in the second time unit, i.e. the first terminal device sends the first sidestream information in the second time unit, then the duration of the first gap takes a value of 25 microseconds. At this point, the first terminal device will transmit the CPE on the third time unit such that the first gap is less than 25 microseconds, as the second time unit is shared to transmit the PSCCH/PSSCH. Since the first gap is less than 25 microseconds, the procedure that other terminals want to access the channel through the type 2A LBT will be terminated, so that the S-SSB cannot be transmitted on the second time unit, and therefore, the collision of simultaneously transmitting the S-SSB and the PSCCH/PSCCH on the second time unit can be avoided.

When the sidestream terminal accesses the channel by means of type 2A and transmits S-SSB in the second time unit, and needs to be shared by type 2A to access the channel and transmit PSCCH/PSSCH in the second time unit, the duration of the first gap takes a value of 25 microseconds. For example, the first terminal device sends the second sidestream information, the first terminal device sends the CPE in the third time unit, the first terminal device is shared with the access channel and sends the S-SSB in the second time unit, i.e. the first terminal device sends the first sidestream information in the second time unit, and then the duration of the first gap takes a value of 25 microseconds. At this point, since the second time unit transmits the S-SSB over the type 2A active access channel, the first terminal device will transmit the CPE on the third time unit such that the first gap is greater than 25 microseconds, e.g., 34us. Since the first gap is greater than 25 microseconds, other terminal devices can preempt in advance through type 2A at this time, so that a collision of simultaneously transmitting S-SSB and PSCCH/PSSCH on the second time unit can be avoided. At this time, the sending performance of the S-SSB in the system is preferentially ensured.

The CPE comprises a first type CPE and a second type CPE, wherein the first type CPE is a CPE for transmitting a side line synchronous signal by a first terminal device, the second type CPE is a CPE for transmitting a side line shared channel by the first terminal device, and the duration of the first type CPE is different from the duration of the second type CPE.

In one implementation, the length of time of the first type of CPE is greater than the length of time of the second type of CPE.

In one implementation, the duration of the first type of CPE is less than the duration of the second type of CPE.

In one implementation manner, the first terminal device obtains first indication information; the first indication information is used for indicating that the duration of the first type CPE is longer than the duration of the second type CPE; or the first indication information is used for indicating that the duration of the first type CPE is smaller than the duration of the second type CPE.

In one implementation, the first indication information is preconfigured or network configured.

For example, as shown in fig. 8 (a), assume that one slot contains 14 OFDM symbols, the second time unit is slot 2, and the third time unit is slot 1, ue1 sends CPE on the GAP symbol of slot 1 (the last symbol of instant 1). As shown in the figure, UE1 transmits a side row synchronization signal on slot 2.

The symbols before the last symbol of the slot 1, for example, symbols 0 to 12, further include second sidestream information, where the second sidestream information may be sent by UE1 or may be sent by other UEs.

If the GAP between the second sidestream information and the CPE is less than 25 μs at this time, then UE 1 sends the CPE on the last OFDM symbol (i.e., GAP symbol) in slot 1, so that the GAP between the information in slot 1 and the CPE in slot 1 is less than 25 μs. And no sidestream information is transmitted in the blank gap.

If the GAP between the second side information and the CPE is less than 16 μs, UE 1 transmits the CPE on the last OFDM symbol (i.e., GAP symbol) in slot 1, so that the GAP between the information in slot 1 and the CPE in slot 1 is less than 16 μs. And no sidestream information is transmitted in the blank gap.

In one implementation, the first terminal device sends the first side information over the second time unit. The third time unit preceding the second time unit includes third side row information occupying the last symbol of the third time unit (not occupying all time domain positions of the last symbol). If the first side line information occupies the initial symbol of the second time unit, a transmission gap between the third side line information and the first side line information is smaller than the third gap; the third gap is predefined, preconfigured, or network configured. For example, the duration of the third gap may take on the value of 16 microseconds or 25 microseconds. The third sidestream information may be sent by the first terminal device or may be sent by another terminal device. The transmission gap between the third side line information and the first side line information is smaller than the third gap, and the gap between the ending position of the third side line information and the starting position of the second time unit can be replaced by the gap between the third side line information and the first side line information is smaller than the third gap. The gap may not be used for transmitting information or signals.

The third time unit may further include fourth side line information, where the fourth side line information is sent before the third side line information, and the third side line information and the fourth side line information may be sent by different terminal devices or may be sent by the same side line information.

For example, when the sidestream terminal is shared with the access channel by means of type 2A and transmits PSCCH/PSSCH in the second time unit, the duration of the second gap takes a value of 25 microseconds, either in the resource pool or in the SL BWP; for example, the third terminal device sends third side line information, the first terminal device is shared with the access channel and sends the SCCH/PSSCH in the second time unit, i.e. the first terminal device sends the first side line information in the second time unit, then the duration of the second gap takes a value of 25 microseconds.

For example, when in the resource pool or in the SL BWP, the sidestream terminal may send PSCCH/PSSCH in consecutive multislots, with the second slot having a duration of 16 microseconds. For example, the first terminal device sends the third side-line information, the first terminal device is shared with the access channel and sends the PSCCH/PSSCH in the second time unit, i.e. the first terminal device sends the first side-line information in the second time unit, then the duration of the second gap takes a value of 16 microseconds.

For example, as shown in fig. 8 (b), assume that one slot includes 14 OFDM symbols, the second time unit is slot 2, the third time unit is slot 1, and the third side line information occupies symbols 0 to 9 of slot 1. As shown in the figure, UE1 transmits a side row synchronization signal on slot 2.

The third side row information of the slot 1 may be preceded by, for example, symbol 8 and symbol 9, and fourth side row information may be sent by the UE1 or sent by another UE.

If the gap between the third side line information and the first side line information is smaller than 25 μs, the blank gap between the time slot 1 and the time slot 2 is smaller than 25 μs.

If the gap between the third side line information and the first side line information is smaller than 16 μs, the blank gap between the time slot 1 and the time slot 2 is smaller than 16 μs. And no sidestream information is transmitted in the blank gap.

It should be appreciated that the two implementations described above are equally applicable to the case where UE1 transmits a physical side link feedback channel (physical sidelink feedback channel, PSFCH), for example, as shown in fig. 8 (c), assuming that one slot contains 14 OFDM symbols, the second time unit is slot 2, and the third time unit is slot 1.

UE1 transmits sidestream information on the PSFCH symbols of slot 1 (i.e., symbol 11 and symbol 12), UE1 transmits third sidestream information on symbol 13 of slot 1, and if UE 2 transmits sidestream synchronization signals on slot 2, then the gap between the third sidestream information and the sidestream synchronization signals transmitted by UE 2 is less than 16 μs or 25 μs.

In another implementation, the first terminal device transmits the side uplink synchronization signal block at the second time unit in any of the following cases:

the ratio of the number of time units in which the first terminal device fails to transmit the side uplink synchronization signal block in the N time units to the number of time units in which the first terminal device succeeds in transmitting the side uplink synchronization signal block in the N time units is greater than or equal to a first factor, the first factor being greater than or equal to 0;

or the ratio of the number of time units in which the first terminal equipment successfully transmits the side uplink synchronous signal block in the N time units to the number of time units in which the first terminal equipment fails to transmit the side uplink synchronous signal block in the N time units is smaller than or equal to a second factor, wherein the second factor is larger than or equal to 0;

or the ratio of the number of time units in which the first terminal equipment fails to send the side uplink synchronous signal block in N time units to the N time units is greater than or equal to a third factor, wherein the third factor is greater than or equal to 0;

Or the ratio of the number of time units in which the first terminal equipment successfully sends the side uplink synchronous signal blocks in the N time units to the N time units is smaller than or equal to a fourth factor, and the fourth factor is larger than or equal to 0.

The first factor, the second factor, the third factor and the fourth factor are preset, can be configured for the network equipment, and can be determined for the first terminal equipment.

In another implementation, the first terminal device does not transmit the sidelink synchronization signal block at the second time unit, or transmits other data or signals than the sidelink synchronization signal block at the second time unit, such as physical sidelink shared channel data, and/or physical sidelink shared channel data, in any of the following cases:

the ratio of the number of time units in which the first terminal equipment fails to transmit the side uplink synchronization signal block in the N time units to the number of time units in which the first terminal equipment succeeds in transmitting the side uplink synchronization signal block in the N time units is less than or equal to a fifth factor, wherein the fifth factor is greater than or equal to 0;

or the ratio of the number of time units in which the first terminal equipment successfully transmits the side uplink synchronous signal block in the N time units to the number of time units in which the first terminal equipment fails to transmit the side uplink synchronous signal block in the N time units is greater than or equal to a sixth factor, wherein the sixth factor is greater than or equal to 0;

Or the ratio of the number of time units in which the first terminal equipment fails to send the side uplink synchronous signal block in N time units to the N time units is smaller than or equal to a seventh factor, wherein the seventh factor is larger than or equal to 0;

or the ratio of the number of time units in which the first terminal equipment successfully transmits the side uplink synchronous signal blocks in the N time units to the N time units is greater than or equal to an eighth factor, and the eighth factor is greater than or equal to 0.

The fifth factor, the sixth factor, the seventh factor and the eighth factor are preset, can be configured for the network device, and can be determined for the first terminal device.

In the present application, the second time unit is located in the first period and is a time unit other than N time units.

In the application, the first terminal equipment competes for a channel before each time unit sends the side uplink synchronous signal block, and if the channel competition is successful, the first terminal equipment sends the side uplink synchronous signal block in the time unit; if the channel contention fails, the first terminal device does not transmit the side uplink synchronization signal block at the time unit, for example, by performing an LBT operation. If the first terminal device succeeds in LBT before the time unit of transmitting the side uplink synchronization signal block, the first terminal device transmits the side uplink synchronization signal block on the time unit; if the first terminal device fails LBT before the time unit in which the side uplink synchronization signal block is transmitted, the first terminal device does not transmit the side uplink synchronization signal block on the time unit. For this purpose, in the present application, the failure of the first terminal device to transmit the side uplink synchronization signal block at the first time unit may refer to:

The first terminal equipment cannot send the side uplink synchronous signal block in the first time unit due to the fact that the first terminal equipment does not compete for the channel before the first time unit successfully;

alternatively, the first terminal device cannot transmit the side uplink synchronization signal block in the first time unit due to the fact that LBT was not successful before the first time unit;

alternatively, the first terminal device succeeds in LBT before the first time unit, but the side-uplink synchronization signal block transmitted in the first time unit is not successfully transmitted to the second terminal device.

Step 703: the second terminal device determines N time units in the first period according to the first configuration information.

Step 704: the second terminal device fails to receive the side uplink synchronization signal block in a first time unit of the N time units, or the number of time units in which the second terminal device fails to receive the side uplink synchronization signal block in the N time units is greater than a first threshold, and the second terminal device receives the side uplink synchronization signal block in the second time unit.

The second terminal device may perform synchronization operation according to the received side uplink synchronization signal block, and the specific process is not described herein. After the second terminal device completes synchronization according to the side uplink synchronization signal block, the second terminal device can communicate with the first terminal device, and the specific process is not repeated.

In another first implementation manner, the second terminal device receives the side uplink synchronization signal block successfully in a first time unit of the N time units, or the number of time units in which the second terminal device fails to receive the side uplink synchronization signal block in the N time units is less than or equal to a first threshold, or the number of time units in which the second terminal device receives the side uplink synchronization signal block successfully in the N time units is greater than or equal to a second threshold, and then the second terminal device may not receive the side uplink synchronization signal block in the second time unit any more; or the second terminal device receives other data or signals than the side-link synchronization signal block in the second time unit, e.g. receives physical side-row shared channel data and/or physical side-row shared channel data.

In this application, the failure of the second terminal device to receive the side uplink synchronization signal block in the first time unit may refer to: the second terminal device does not receive the side uplink synchronization signal block in the first time unit; alternatively, the second terminal device receives the side-link synchronization signal block in the first time unit, but fails to decode the side-link synchronization signal block.

In this application, there may be multiple implementations of the second time unit, which are described below by way of example.

In the first implementation manner, in the first period, additional (additional) M time units may be configured, where the second time unit belongs to M time units, and M is an integer greater than 0. The M time units are also candidate time units for the transmission side uplink synchronization signal block. That is, the first configuration information may be used to determine the N time units in the first period, and the first configuration information may also be used for the N time units in the first period and the M time units in the first period.

In this implementation, the first terminal device fails to transmit the side uplink synchronization signal block in a first time unit of the N time units, and transmits the side uplink synchronization signal block in a second time unit. The first terminal device does not transmit the side uplink synchronization signal block in the second time unit if the side uplink synchronization signal block is successfully transmitted in the first time unit.

Correspondingly, the second terminal device fails to receive the side uplink synchronization signal block in a first time unit of the N time units, and receives the side uplink synchronization signal block in the second time unit. The second terminal equipment receives the side uplink synchronous signal block successfully in a first time unit in N time units, and does not receive the side uplink synchronous signal block in a second time unit; or other data or signals than the side-link synchronization signal block, such as physical side-row shared channel data, and/or physical side-row shared channel data, are received in the second time unit.

Alternatively, in this implementation, the first terminal device transmits the side uplink synchronization signal block in the second time unit if the number of time units in which the transmission of the side uplink synchronization signal block fails in the N time units is greater than the first threshold. The number of time units in which the first terminal device fails to transmit the side downlink synchronization signal block in the N time units is less than or equal to the first threshold, or the number of time units in which the first terminal device succeeds in transmitting the side downlink synchronization signal block in the N time units is greater than or equal to the second threshold, the side downlink synchronization signal block is not transmitted in the second time unit. For example, the first terminal device may send other data or signals than the side-uplink synchronization signal block, such as physical side-shared channel data, and/or physical side-shared channel data, in the second time unit.

Correspondingly, the second terminal device receives the side uplink synchronization signal block in the second time unit if the number of time units in which the second terminal device fails to receive the side uplink synchronization signal block in the N time units is greater than the first threshold. The number of time units in which the second terminal device fails to receive the side-link synchronization signal block in the N time units is less than or equal to the first threshold, or the number of time units in which the second terminal device succeeds in receiving the side-link synchronization signal block in the N time units is greater than or equal to the second threshold, the second terminal device does not receive the side-link synchronization signal block in the second time unit, or the second terminal device receives other data or signals than the side-link synchronization signal block in the second time unit, such as physical side-row shared channel data, and/or physical side-row shared channel data.

In one possible implementation, the first terminal device transmits the side uplink synchronization signal block in each of the M time units.

In one possible implementation, if the first terminal device fails to transmit the side uplink synchronization signal block in X time units of the N time units, the first terminal device transmits the side uplink synchronization signal block in at most X time units of the M time units, and may not transmit the side uplink synchronization signal block any more in time units other than the X time units of the M time units, where X is an integer greater than 0 and less than or equal to N.

In this implementation, the time domain positions of the M time units may be configured by the first configuration information, so that the first terminal device may determine the M time units according to the first configuration information. The time domain positions of the M time units may also be configured by a single configuration information, for example by a second configuration information. The time domain positions of the M time units may also be preset, which is not limited in the present application.

There are many implementations of how the time-domain positions of the M time units can be configured in particular. In a possible implementation, when m=1, the M time units include only the second time unit, and the second time unit may be configured by a first time length, where the first time length represents an interval between the second time unit and one of the N time units, for example, an interval between the second time unit and a first time unit or a last time unit of the N time units, for example, by a first time length. The first duration is configured by the network device, for example, the first duration is configured by the first configuration information; or, the first duration is a preconfigured duration; alternatively, the first duration is a duration specified by the protocol.

For example, as shown in fig. 8 (d), S-SSB in fig. 8 (d) represents a side-uplink synchronization signal block, and in fig. 8 (a), the second time unit is spaced apart from the last time unit of the N time units by a first duration; in fig. 8 (b), the second time unit is spaced a first duration from the first time unit of the N time units.

In one possible implementation, when M is greater than 1, the M time units include other time units in addition to the second time unit. In this implementation, the M time units may be configured by a first duration and a first interval duration. Wherein the first duration represents a duration of an interval between one of the M time units (e.g., the second time unit) and one of the N time units, e.g., the second time unit of the M time units and the first time unit or the last time unit of the N time units; the first interval duration represents a time slot interval between two adjacent time units in the M time units. The configuration manner of the interval duration may refer to the first duration and will not be described herein.

For example, as shown in fig. 9, S-SSB in the figure represents a side uplink synchronization signal block, and an interval between two adjacent time units in M time units is a first interval duration, which may be equal to an interval duration between two adjacent time units in N time units. In fig. 9 (a), a first time interval is formed between a first time unit of the M time units and a last time unit of the N time units; in fig. 9 (b), a first time unit of the M time units is spaced apart from a first time unit of the N time units by a first duration.

In a second implementation, a second time unit is configured for a first time unit of the N time units, where the first time unit and the second time unit are associated.

In this implementation, the first terminal device fails to transmit the side downlink synchronization signal block in the first time unit, and transmits the side downlink synchronization signal block in the second time unit. The first terminal device does not transmit the side uplink synchronization signal block in the second time unit if the side uplink synchronization signal block is successfully transmitted in the first time unit.

Correspondingly, the second terminal device fails to receive the side uplink synchronization signal block in the first time unit, and receives the side uplink synchronization signal block in the second time unit. The second terminal equipment receives the side uplink synchronous signal block successfully in a first time unit in N time units, and does not receive the side uplink synchronous signal block in a second time unit; or other data or signals than the side-link synchronization signal block, such as physical side-row shared channel data, and/or physical side-row shared channel data, are received in the second time unit.

In this implementation, a second time period is spaced between the first time unit and the second time unit. The second duration is configured by the network device, for example, the second duration is configured by the network device through the first configuration information, or the second duration may also be configured through a single configuration information; or, the second duration is a preconfigured duration; alternatively, the second duration is a duration specified by the protocol.

In one possible implementation, a second time unit may also be configured for each of the N time units. The intervals between the different time units and their associated second time units may be the same (e.g., both are of a second duration), or the intervals between the different time units and their associated second time units may be different.

For example, as shown in fig. 10, S-SSB in the figure represents a side uplink synchronization signal block, each of N time units is configured with a second time unit, and an interval between each time unit and its associated second time unit is a second duration. In the figure, a white grid represents a time cell of the N time cells, and a black grid represents a second time cell.

In this implementation, for any one of the N time units, e.g., a first time unit, the first terminal device fails to transmit a side downlink synchronization signal block in the first time unit, and then transmits the side downlink synchronization signal block in a second time unit associated with the first time unit. The first terminal device transmits the side-link synchronous signal block successfully in the first time unit, and does not transmit the side-link synchronous signal block in the second time unit associated with the first time unit. For example, the first terminal device may send other data or signals than the side-uplink synchronization signal block, such as physical side-shared channel data, and/or physical side-shared channel data, in the second time unit.

Accordingly, for any one of the N time units, for example, a first time unit, the second terminal device fails to receive the side uplink synchronization signal block in the first time unit, and then receives the side uplink synchronization signal block in the second time unit associated with the first time unit. The second terminal device receives the side-link synchronous signal block successfully in the first time unit, and does not receive the side-link synchronous signal block in the second time unit associated with the first time unit. For example, the second terminal device may receive other data or signals than the side-uplink synchronization signal block, e.g., physical side-shared channel data, and/or physical side-shared channel data, at the second time unit.

In one possible implementation, a plurality of second time units may also be configured for each of the N time units. For any one of the N time units, an interval between two adjacent second time units in the plurality of second time units associated with the time unit is a second interval duration. The configuration manner of the second interval duration may refer to the second duration, and will not be described herein.

For example, as shown in fig. 11, S-SSB in the figure represents a side-uplink synchronization signal block, each of N time units is configured with 2 second time units, in the figure, white boxes represent time units of the N time units, and black boxes represent second time units. A first time unit of the 2 second time units corresponding to each time unit is separated from the time unit by a second duration.

In this implementation, for any one of the N time units, e.g., a first time unit, the first terminal device fails to transmit a side uplink synchronization signal block in the first time unit, and then transmits the side uplink synchronization signal block in at least one of a plurality of second time units associated with the first time unit. The first terminal device transmits the side-link synchronization signal block successfully in the first time unit, and does not transmit the side-link synchronization signal block in a plurality of second time units associated with the first time unit.

Accordingly, for any one of the N time units, e.g., a first time unit, the second terminal device fails to receive the side uplink synchronization signal block in the first time unit, and receives the side uplink synchronization signal block in at least one of a plurality of second time units associated with the first time unit. The second terminal device receives the side uplink synchronization signal block successfully in the first time unit, and does not receive the side uplink synchronization signal block in a plurality of second time units associated with the first time unit.

In a third implementation, the first terminal device may send the first side uplink control information to the second terminal device after determining to send the side uplink synchronization signal block in the second time unit.

In the present application, the first side-link control information may be defined by first-order side-link control information (1 ^st The stage SCI can be carried by second order side-link control information (2 ^nd The stage SCI) bearer may also be carried by a media access control (medium access control, MAC) Control Element (CE), which is not limited in this application.

In this application, the first side uplink control information may include one or more of the following functions:

the first side uplink control information is used to determine a second time unit;

the first side uplink control information is used to indicate side uplink synchronization signal block information other than N time units in the first period, for example, to indicate whether other side uplink synchronization signal block information is included or not other than N time units in the first period, or to indicate other side uplink synchronization signal block resource location information other than N time units in the first period;

the first side-link control information is used for indicating that the side-link synchronous signal block is included in the second time unit;

the first side-link control information is used to indicate whether the side-link synchronization signal block is included in the second time unit.

In one implementation, the first terminal device transmits the first side-link control information only when the side-link synchronization signal block is transmitted outside of N time units.

In this implementation, the first side-link control information is used to indicate that the side-link synchronization signal block is included in the second time unit, or the first side-link control information is used to indicate that other side-link synchronization signal blocks are included in addition to the N time units.

In this implementation, the first terminal device may first transmit the first side uplink control information and then transmit the side uplink synchronization signal block in the second time unit when the first time unit fails to transmit the side uplink synchronization signal block or when the number of time units for which the transmission side uplink synchronization signal block fails is greater than the first threshold.

Accordingly, the second terminal device receives the first side uplink control information, and determines to receive the side uplink synchronization signal block outside of the N time units in the first period, or determines to receive the side uplink synchronization signal block in the second time unit.

In this implementation, if the first terminal device does not transmit the first side uplink control information, the first terminal device does not transmit the side uplink synchronization signal block outside of the N time units in the first period. Accordingly, the second terminal device does not receive the first side uplink control information, determines not to receive the side uplink synchronization signal block outside of the N time units in the first period, or determines not to receive the side uplink synchronization signal block in the second time unit.

For example, in this implementation, the first side-link control information may also be used to determine the second time unit.

For example, the second time unit may correspond to the first side link control information, and how the second time unit corresponds to the first side link control information is not limited in this application. For example, as shown in fig. 12, a time unit spaced apart from the first side link control information by a third duration may be taken as the second time unit. The second terminal device thus receives the side uplink synchronization signal block at a time unit spaced a third duration from the first side uplink control information after receiving the side uplink control information. SCI in the figure represents the first side uplink control information, and time units including S-SSB in the figure represent time units among N time units. How the third duration is configured may refer to a configuration method of the second duration, which is not described herein.

As another example, the first side uplink control information may also be used to determine one or more of: the location of the second time cell; the position of the set of sub-channels or interleaved resource blocks occupied by the side-uplink synchronization signal block in the second time unit.

The second terminal device then determines a second time unit based on the first side-link control information after receiving the first side-link control information, such that the side-link synchronization signal block is received at the second time unit.

For example, the first side-link control information includes Y1 bits, and the value of the Y1 bits may indicate the position of the second time unit.

For example, assuming y1=2, the positional relationship between the value of Y1 and the second time unit can be shown in table 1.

TABLE 1

Value of Y1	The position of the second time unit
		00	Preset position in COT
01	Third time cell in COT
		10	Fourth time cell in COT
11	Last time unit in COT

Referring to table 1, if the value of Y1 bits is 00, this indicates that the second time unit is at the preset position in the COT, and other cases will not be described again.

For another example, the positional relationship between the value of Y1 and the second time unit can be as shown in table 2.

TABLE 2

Value of Y1	The position of the second time unit
		00	Preset position within the COT
01	2
		10	3
11	4

Referring to table 2, if the value of Y1 bits is 00, it indicates the preset position of the second time unit in the COT; if the value of Y1 bits is 01, it indicates that the second time unit is the 2 nd time unit after the first time unit in the COT, and other cases will not be described again.

For example, the first side-link control information may also include Y2 bits, and the value of these Y2 bits may indicate the location of the sub-channel or set of interleaved resource blocks occupied by the side-link synchronization signal block.

For example, assuming y2=2, the positional relationship between the values of Y2 and the sub-channels can be as shown in table 3.

TABLE 3 Table 3

For another example, the positional relationship between the value of Y2 and the sub-channel can be as shown in table 4.

TABLE 4 Table 4

Value of Y2	Sub-channel location
		00	Preset frequency domain locations within COT
01	2
		10	3
11	4

Referring to table 4, if the value of Y2 bits is 00, indicating the preset frequency domain position of the subchannel in the COT; and when the value of the Y1 bit is other values, the offset value of the sub-channel and the lowest sub-channel in the preset RB set (the RB set with the lowest index or the RB set with the highest index) in the COT is indicated. For example, the index number of the lowest subchannel in the preset RB set is n, the value of Y1 bits is 01, the offset value is 2, and the index number of the subchannel is n+2; the Y1 bits have a value of 02 and an offset of 3, indicating that the index number of the subchannel is n+3.

In one implementation, the first side uplink control information is transmitted regardless of whether the first terminal device transmits the side uplink synchronization signal block outside of N time units.

In this implementation, the first side-link control information is used to indicate whether a side-link synchronization signal block is included in the second time unit or whether other side-link synchronization signal blocks are included in addition to the N time units.

In this implementation, the first side uplink control information may include two values: a first value and a second value. When the first terminal equipment sends the side uplink synchronous signal blocks outside N time units, the first side uplink control information corresponds to a first value; when the first terminal device does not transmit the side uplink synchronization signal block outside the N time units, the first side uplink control information corresponds to the second value.

In this implementation manner, when the first terminal device fails to send the side uplink synchronization signal block in the first time unit, or the number of time units that fail to send the side uplink synchronization signal block is greater than the first threshold, the first side uplink control information sent by the first terminal device corresponds to the first value, and is used for indicating that the side uplink synchronization signal block is further included in addition to the N time units in the first period, or is used for indicating that the side uplink synchronization signal block is further included in the second time unit.

Correspondingly, the second terminal device determines that the received first side uplink control information corresponds to the first value, and receives the side uplink synchronization signal block outside the N time units or receives the side uplink synchronization signal block in the second time unit.

In this implementation manner, when the first terminal device transmits the side uplink synchronization signal block successfully in the first time unit, or the number of time units in which the transmission of the side uplink synchronization signal block fails is less than or equal to the first threshold, the first side uplink control information transmitted by the first terminal device corresponds to the second value, which is used for indicating that the side uplink synchronization signal block is not included out of N time units in the first period, or is used for indicating that the side uplink synchronization signal block is not included in the second time unit.

Correspondingly, the second terminal device determines that the received first side uplink control information corresponds to the second value, and does not receive the side uplink synchronization signal block outside the N time units or does not receive the side uplink synchronization signal block in the second time unit.

In this implementation manner, the first side uplink control information may also be used to determine the second time unit, and specific reference may be made to the foregoing description, which is not repeated herein.

In a fourth implementation manner, the position of the second time unit is not fixed, and is determined by the first terminal device according to the actual situation. For example, when the first terminal device fails to transmit the side uplink synchronization signal block in the first time unit or the number of time units for which the transmission side uplink synchronization signal block fails is greater than the first threshold, the first terminal device tries to perform LBT operation in time units other than N time units, and if LBT passes, the side uplink synchronization signal block may be transmitted.

In this implementation, the location of the second time unit is dynamic and the second terminal device may attempt to receive the side uplink synchronization signal block in a time unit other than N time units.

As shown in fig. 13, a schematic flow chart of a method for transmitting a side-link synchronization signal block according to an embodiment of the present application is provided, and the structures of various side-link synchronization signal blocks described in the flow chart of fig. 13 are also applicable to the flow chart shown in fig. 7, which is not separately illustrated herein.

Step 1301: the first terminal equipment generates a side uplink synchronous signal block;

step 1302: the first terminal device sends a side uplink synchronous signal block to the second terminal device; accordingly, the second terminal device receives the side uplink synchronization signal block from the first terminal device.

Step 1303: the second terminal device performs synchronization according to the side-uplink synchronization signal block.

In one implementation, the side-uplink synchronization signal block includes PSBCH, S-SSS, and S-PSS, where S-SSS and S-PSS may be collectively referred to as a side-uplink synchronization sequence. In one possible physical structure of the synchronization signal block, the PSBCH occupies a plurality of continuous resource blocks or a plurality of discontinuous resource blocks; the side-link synchronization sequence occupies a plurality of consecutive resource blocks or resource elements (resource elements), or the side-link synchronization sequence occupies a plurality of non-consecutive resource blocks or resource elements. Wherein, PSBCH occupies Z resource blocks, Z is a positive integer, Z is configured by a network, or is preconfigured, or is agreed by a protocol. The number of resource blocks occupied by the side-uplink synchronization sequence is equal to 11 or 12.

In one implementation, the side-uplink synchronization signal block includes PSBCH, S-SSS, and S-PSS, where S-SSS and S-PSS may be collectively referred to as a side-uplink synchronization sequence. In one possible physical structure of the synchronization signal block, the PSBCH occupies a plurality of discontinuous resource blocks; the side-link synchronization sequence occupies a plurality of non-contiguous resource blocks or resource elements (resource elements). Wherein, the S-SSB occupies Z1 resource blocks, Z1 is a positive integer, and Z1 is configured by a network, or preconfigured, or agreed by a protocol.

In one implementation, as shown in fig. 14, in the frequency domain, the side-link synchronization sequence and the PSBCH occupy 132 consecutive subcarriers, and assuming that the 132 subcarriers are numbered 0 to 131, when one RB includes 12 subcarriers, the 132 subcarriers correspond to 11 RBs. When one side uplink synchronous signal block occupies 11 RBs, PSBCH occupies all sub-carriers corresponding to the 11 RBs, namely 132 sub-carriers with PSBCH occupied numbers of 0-131; while the side-link synchronization sequence occupies 127 subcarriers of the 132 subcarriers, specifically, the side-link synchronization sequence occupies 127 consecutive subcarriers numbered 2 to 128, and is set to 0 on subcarrier 0,1,129,130,131. I.e. the starting Resource Element (RE) occupied by the side-link synchronization sequence is offset by 2 REs with respect to the starting RE or the lowest index RE occupied by the PSBCH, and the starting and ending RE occupied by the side-link synchronization sequence is offset by 3 REs with respect to the ending RE occupied by the PSBCH, wherein RE is defined as a resource element of one OFDM symbol length in time and one subcarrier width in frequency.

In the present application, if the side-uplink synchronization sequence is transmitted in the resource pool of the first terminal device, the first terminal device may further indicate a frequency domain location occupied by the side-uplink synchronization signal block. For example, the first terminal device may further indicate that an offset value between a start point of a frequency domain resource occupied by the side uplink synchronization signal block and a start point of a frequency domain resource of the channel occupied by the first terminal device is the first frequency domain offset value. The first frequency domain offset value may also be preset, which is not limited in this application. The first frequency domain offset value may also be an offset value of a starting point of a frequency domain resource occupied by the side uplink synchronization signal block relative to a frequency domain resource end position of the channel, or a position in between.

In the present application, the first terminal device may further indicate a frequency domain location occupied by the side uplink synchronization sequence. For example, the first terminal device may indicate a second frequency domain offset value between a starting point of frequency domain resources occupied by the side-uplink synchronization sequence and a starting point of frequency domain resources occupied by the first terminal device. The second frequency domain offset value may also be preset, which is not limited in this application. The second frequency domain offset value may also be an offset value of a starting point of a frequency domain resource occupied by the side uplink synchronization sequence relative to a frequency domain resource end position of the channel, or a position in between.

In the present application, when the subcarrier spacing of the channel occupied by the first terminal device is different, the number of resource blocks occupied by the side uplink synchronization sequence and the PSBCH may be different, which will be described below.

In one implementation, the subcarrier spacing of the channel occupied by the first terminal device is less than 60kHz.

In this implementation, the resource blocks occupied by the PSBCH are located in the first frequency domain resources, and/or the second frequency domain resources. The first frequency domain resource is located on a sub-channel or an interleaving resource block set, the second frequency domain resource is a resource block, and the first frequency domain resource and the second frequency domain resource are adjacent in position. Or,

In this implementation, the resource blocks occupied by the S-SSB are located in the first frequency domain resources, and/or the second frequency domain resources. The first frequency domain resource is located on a sub-channel or an interleaving resource block set, the second frequency domain resource is a resource block, and the first frequency domain resource and the second frequency domain resource are adjacent in position.

In one implementation, the Z resource blocks occupied by the PSBCH are located on 1 interlace/subchannel and 1 resource block, which is adjacent to 1 resource block in the 1 interlace/subchannel.

In one implementation, Z1 resource blocks occupied by S-SSB are located on 1 interlace/subchannel and 1 resource block, the 1 resource block being adjacent to 1 resource block in the 1 interlace/subchannel.

In one implementation, the PSBCH occupies Z resource blocks in 1 or 2 interlaces, or in 1 or 2 subchannels. When the resource block occupied by the PSBCH is located in 2 interlaces, the 2 interlaces are adjacent. Alternatively, when the resource block occupied by the PSBCH is located at 2 sub-channels, the 2 sub-channels are located adjacent to each other.

In one implementation, the S-SSB occupies Z resource blocks in 1 or 2 interlaces, or in 1 or 2 subchannels. When the resource block occupied by the PSBCH is located in 2 interlaces, the 2 interlaces are adjacent. Alternatively, when the resource block occupied by the PSBCH is located at 2 sub-channels, the 2 sub-channels are located adjacent to each other.

In one implementation, the PSBCH occupies 10 RBs. Such side-uplink synchronization signal blocks may meet the occupied channel bandwidth (occupied channel bandwidth, OCB) requirements.

In one implementation, the S-SSB occupies 10 RBs. Such side-uplink synchronization signal blocks may meet the occupied channel bandwidth requirements.

For example, as shown in fig. 15, the start RB number of the RB set where the side-link synchronization signal block is located is 0. The PSBCH occupies 10 discontinuous RBs, for example, 10 RBs in an interleaving resource block set with index of 0; the second frequency domain offset value is 10, indicating that the link synchronization sequence occupies 127 consecutive REs from the 10 th RB, or 11 consecutive RBs from the 10 th RB (the first 3 REs from the 10 th RB in this implementation are set to 0).

For example, as shown in fig. 16, the start RB number of the RB set where the side-link synchronization signal block is located is 0. The PSBCH occupies 10 RBs in the interleaved resource block set with index 0, and the index of the 10 RBs is: {0,10,20,30, … }; the side-link sync sequence occupies 11 RBs with an index of 0 to 10, but the starting RE occupied by the side-link sync sequence is offset by 3 REs with respect to the starting RE occupied by the PSBCH, i.e., REs occupied by the side-link sync sequence in RBs with an index of 0 start from the 4 th RE.

For example, as shown in fig. 17, the start RB number of the RB set where the side-link synchronization signal block is located is 0. The PSBCH occupies 10 RBs in the interleaved resource block set with index 0, and the index of the 10 RBs is: {0,10,20,30, … }; the side-link sync sequence occupies 11 RBs with indexes 80 to 90, but the end RE occupied by the side-link sync sequence is offset by 2 REs with respect to the end RE occupied by the PSBCH, i.e., the last RE occupied by the side-link sync sequence in an RB with index 90 is the 10 th RE in the RB.

In one implementation, the PSBCH occupies 11 RBs, where the resource blocks occupied by the PSBCH are located in 1 or 2 interlaces, or the resource blocks occupied by the PSBCH are located in 1 or 2 sub-channels.

In one implementation, the S-SSB occupies 11 RBs, where the resource blocks occupied by the S-SSB are located in 1 or 2 interlaces, or the resource blocks occupied by the S-SSB are located in 1 or 2 subchannels.

For example, as shown in fig. 18, the start RB number of the RB set where the side-link synchronization signal block is located is 0. The PSBCH occupies 10 RBs in the set of interleaved resource blocks with index 0 and 1 RB in the set of interleaved resource blocks with index 0, and the indexes of the 11 RBs are: {0,1,10,20,30, … }.

In one implementation, the side-uplink synchronization sequence may occupy 134 REs of the 12 RBs when the subcarrier spacing of the channel is 15 kHz. 7 REs out of 134 may be filled at this time, for example, any of the following modes may be adopted:

mode 1: all/part of the data or signals on 1 or more RBs on the PBSCH are duplicated and then padded at either or both ends of the side uplink synchronization sequence, respectively. For example, the data or signal in the RB with the lowest index occupied by the PBSCH may be copied and then padded in REs at both ends of the side uplink synchronization sequence, respectively, and only 7 REs may be padded or more. It is also possible to fill only one end of the side-link synchronization sequence, for example to place the duplicated signal or data at the beginning or end of the side-link synchronization sequence.

Mode 2: sequence filling is carried out on two ends or a certain end of the side-link synchronous sequence, the filling sequence can be a newly generated sequence, and the criterion of minimum peak-to-average power ratio is satisfied after the newly generated sequence acts with the original side-link synchronous sequence; the padding sequence may be a copy of the original side uplink synchronization sequence, and only 7 RE-sized sequence lengths need to be copied at this time, or a sequence length greater than 7 REs may be used, and the 7 RE-sized sequence lengths may be a complete copy from a certain segment of continuous sequence, or may be copies and padding at both ends of the original side uplink synchronization sequence.

In addition, after filling the beginning or ending of the side-link synchronization sequence, the frequency domain rule of the extended S-SSB signal may satisfy: 1) The start position of the padded data or signal may be the start of one RB or the lowest RB number of the index in one interleaved resource set (if the beginning of the sequence has padding); 2) Then immediately followed by the original side-uplink synchronization sequence; 3) The end-of-sequence padding data or sequence is finally followed (if the end-of-sequence has padding). In particular, the padding data may start from a start position of 1 RB at this time, and then the side-link synchronization sequence may start from a start position of one RB, that is, some REs may be set to 0 between the padding data and the side-link synchronization sequence at this time, and the frequency domain positions thereof are not necessarily immediately adjacent.

In a second implementation manner, the subcarrier spacing of the channel occupied by the first terminal device is equal to 60kHz.

In this implementation, if the PSBCH occupies discontinuous resource blocks, the number of occupied resource blocks is 11, and 1 resource block is spaced between two adjacent resource blocks in the 11 resource blocks; the side-uplink synchronization sequence occupies 11 consecutive resource blocks.

In this implementation, bit bitmap indication information may be introduced, which is used to indicate the locations of resource blocks occupied by the PSBCH in the channel. The length of the bit map indication information is equal to the number of available RBs in the channel set or the channel or the at least one nominal channel or the at least one 20MHz channel bandwidth, e.g. in a 60kHz subcarrier spacing configuration the number of RBs available for 20MHz frequency domain bandwidth is equal to 24, then the length of the bit map indication information is equal to 24.

For example, the value of one bit in the bit map indicating information is "1", which indicates that the RB corresponding to the bit is used for transmitting the PSBCH, and the value of one bit in the bit map indicating information is "0", which indicates that the RB corresponding to the bit is not used for transmitting the PSBCH. For example, as shown in FIG. 19, when one RB set contains 24 RBs, if the index of the 24 RBs is 0 to 23, respectively, the RB occupied by the PSBCH is {0,2,4,6,8,10,12,14,16,18,20}. The corresponding bit map indication information may be: 101010101010101010101000.

in this implementation, the bit map indication information is preconfigured, or configured by the network device, or agreed upon by the protocol, or may also be indicated by the first terminal device to the second terminal device.

If the PSBCH occupies consecutive resource blocks, in order to meet the OCB requirement, the PSBCH occupies at least 23 consecutive resource blocks, as shown in detail with reference to fig. 20. At this time, the data corresponding to the original PSBCH can be subjected to rate matching, and the data corresponding to the PSBCH can be expanded from 11 RBs to 23 RBs, or can be expanded to the RB set in the whole channel. For the side-link synchronization sequence, the original continuous sequence transmission is still maintained, namely, 11 continuous resource blocks are occupied.

According to the method provided by the application, the specific S-SSB frequency domain structure and position are defined so as to meet the legal requirement of the sidestream communication in an unlicensed frequency band, and the possible S-SSB frequency domain structures under different configurations are provided according to the configuration condition of the protection bandwidth of the resource pool, so that the synchronization efficiency is provided.

In the embodiments provided in the present application, the methods provided in the embodiments of the present application are described from the perspective of interaction between the respective devices. In order to implement the functions in the methods provided in the embodiments of the present application, the first terminal device or the second terminal device may include a hardware structure and/or a software module, and implement the functions in the form of a hardware structure, a software module, or a hardware structure plus a software module. Some of the functions described above are performed in a hardware configuration, a software module, or a combination of hardware and software modules, depending on the specific application of the solution and design constraints.

The division of the modules in the embodiment of the present application is schematic, which is merely a logic function division, and other division manners may be implemented in practice. In addition, each functional module in the embodiments of the present application may be integrated in one processor, or may exist alone physically, or two or more modules may be integrated in one module. The integrated modules may be implemented in hardware or in software functional modules.

As with the above concept, as shown in fig. 21, the embodiment of the present application further provides a communication apparatus 2100 for implementing the function of the first terminal device or the second terminal device in the above method. For example, the apparatus may be a software module or a system on a chip. In the embodiment of the application, the chip system may be formed by a chip, and may also include a chip and other discrete devices. The communication device 2100 may include: a processing unit 2101 and a transmitting unit 2102.

In this embodiment of the present application, the sending unit may also be referred to as a transceiver unit, and may include a sending unit and/or a receiving unit, which are configured to perform the steps of sending and receiving performed by the first terminal device or the second terminal device in the foregoing method embodiment, respectively.

The following describes in detail the communication device provided in the embodiment of the present application with reference to fig. 21 to 22. It should be understood that the descriptions of the apparatus embodiments and the descriptions of the method embodiments correspond to each other, and thus, descriptions of details not described may be referred to the above method embodiments, which are not repeated herein for brevity.

The transmitting unit may also be referred to as a transceiver, transceiving means, etc. The processing unit may also be called a processor, a processing board, a processing module, a processing device, etc. The transmitting unit may also be referred to as a transceiver, transceiver circuitry, or the like. The transmitting unit may also sometimes be referred to as a transmitter, or a transmitting circuit, etc. The communication device may also include a receiving unit, which may also sometimes be referred to as a receiver, or receiving circuit, etc. The transmitting unit and the receiving unit may be integrated together as one unit or may be two independent units.

In one implementation, the communication device 2100 may perform the following functions:

a processing unit, configured to determine N time units in a first period according to the first configuration information, where N is an integer greater than 0, and the N time units are candidate time units for transmitting a side uplink synchronization signal block;

A transmitting unit, configured to fail to transmit the side uplink synchronization signal block in a first time unit of the N time units, or the number of time units in which the transmitting of the side uplink synchronization signal block in the N time units fails is greater than a first threshold, and configured to transmit the side uplink synchronization signal block to a second terminal device in a second time unit; the second time unit is located in the first period and is a time unit other than the N time units.

In one implementation, the processing unit is further configured to:

and determining M time units according to the first configuration information, wherein M is an integer greater than 0, the M time units are candidate time units used for sending the side uplink synchronous signal blocks, the second time units belong to the M time units, and the M time units are time units outside the N time units in the first period.

In an implementation, the sending unit is further configured to:

and sending first side link control information to the second terminal equipment, wherein the first side link control information is used for determining the second time unit.

In one implementation, the first side-link control information is further used to determine one or more of:

the location of the second time cell;

the location of the set of sub-channels or interleaved resource blocks occupied by the side-uplink synchronization signal block in the second time unit.

In one implementation, the second time unit is spaced a first duration from a first time unit or a last time unit of the N time units.

In one implementation manner, an offset value between a starting point of a frequency domain resource occupied by the side uplink synchronization signal block and a starting point of a frequency domain resource occupied by the first terminal device is a first frequency domain offset value; the first frequency domain offset value is preset, or the first frequency domain offset value is determined for the first terminal device, or the first frequency domain offset value is configured for a network device.

A transmitting unit configured to fail to receive the side uplink synchronization signal block in a first time unit of the N time units, or the number of time units in which the side uplink synchronization signal block fails in the N time units is greater than a first threshold, the transmitting unit being configured to receive the side uplink synchronization signal block in a second time unit; the second time unit is located in the first period and is a time unit other than the N time units.

In one implementation, the processing unit is further configured to:

In an implementation, the sending unit is further configured to: first side uplink control information is received from the first terminal device, the first side uplink control information being used to determine the second time unit.

the location of the second time cell; the location of the set of sub-channels or interleaved resource blocks occupied by the side-uplink synchronization signal block in the second time unit.

The above is only an example, and the processing unit 2101 and the sending unit 2102 may perform other functions, and a more detailed description may refer to the related description in the foregoing method embodiment, which is not repeated here.

As shown in fig. 22, a communication apparatus 2200 provided in an embodiment of the present application, where the apparatus shown in fig. 22 may be an implementation of a hardware circuit of the apparatus shown in fig. 21. The communication device may be adapted to perform the functions of the first terminal device or the second terminal device in the above-described method embodiments in the flowcharts shown above. For convenience of explanation, fig. 22 shows only major components of the communication apparatus.

As shown in fig. 22, the communication device 2200 includes a processor 2210 and an interface circuit 2220. Processor 2210 and interface circuit 2220 are coupled to each other. It is to be appreciated that interface circuit 2220 can be a transceiver or an input-output interface. Optionally, the communication device 2200 may further include a memory 2230 for storing instructions executed by the processor 2210 or for storing input data required by the processor 2210 to execute instructions or for storing data generated after the processor 2210 executes instructions.

When the communication device 2200 is used to implement the method shown above, the processor 2210 is used to implement the functions of the processing unit 2101 described above, and the interface circuit 2220 is used to implement the functions of the transmission unit 2102 described above.

When the communication device is a chip applied to the terminal device, the chip of the terminal device realizes the functions of the terminal device in the method embodiment. The chip of the terminal device receives information from other modules (such as a radio frequency module or an antenna) in the terminal device; alternatively, the chip of the terminal device sends information to other modules (e.g., radio frequency modules or antennas) in the terminal device.

It is to be appreciated that the processor in embodiments of the present application may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), field programmable gate arrays (Field Programmable Gate Array, FPGA) or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general purpose processor may be a microprocessor, but in the alternative, it may be any conventional processor.

The processor in embodiments of the present application may be in random access Memory (Random Access Memory, RAM), flash Memory, read-Only Memory (ROM), programmable ROM (PROM), erasable Programmable ROM (EPROM), electrically Erasable Programmable EPROM (EEPROM), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. In addition, the ASIC may reside in a network device or terminal device. The processor and the storage medium may reside as discrete components in a network device or terminal device.

It will be appreciated by those skilled in the art that 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, 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 the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations 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.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present application without departing from the scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims and the equivalents thereof, the present application is intended to cover such modifications and variations.

Claims

1. A method for transmitting a side-uplink synchronization signal block, comprising:

the first terminal equipment determines N time units in a first period according to the first configuration information, wherein N is an integer greater than 0, and the N time units are candidate time units for transmitting side uplink synchronous signal blocks;

the first terminal equipment fails to send the side-link synchronous signal block in a first time unit in the N time units, or the number of time units in which the first terminal equipment fails to send the side-link synchronous signal block in the N time units is larger than a first threshold value, and the first terminal equipment sends the side-link synchronous signal block to a second terminal equipment in a second time unit; the second time unit is located in the first period and is a time unit other than the N time units.

2. The method according to claim 1, wherein the method further comprises:

3. The method according to claim 1, wherein the method further comprises:

4. A method according to claim 3, wherein the first side-link control information is further used to determine one or more of:

the location of the second time cell;

5. The method of any one of claims 1 to 4, wherein the second time unit is spaced a first duration from a first time unit or a last time unit of the N time units.

6. The method of claim 5, wherein the first duration is a duration configured by a network device;

or, the first duration is a preconfigured duration;

or, the first duration is a duration specified by a protocol.

7. The method of any of claims 1-4, wherein a second time period is spaced between the first time unit and the second time unit.

8. The method of claim 7, wherein the second duration is a duration configured by a network device;

or, the second duration is a preconfigured duration;

or, the second duration is a duration specified by a protocol.

9. The method according to any one of claims 1 to 8, wherein an offset value between a starting point of a frequency domain resource occupied by the side uplink synchronization signal block and a starting point of a frequency domain resource of a channel occupied by the first terminal device is a first frequency domain offset value; the first frequency domain offset value is preset, or the first frequency domain offset value is determined for the first terminal device, or the first frequency domain offset value is configured for a network device.

10. The method according to any of claims 1 to 8, wherein the second time unit comprises first side line information, a third time unit preceding the second time unit comprises a cyclic prefix extension, CPE, the CPE and the first side line information are from the first terminal device, the third time unit and the second time unit are temporally adjacent, and a duration of the CPE is a first transmission duration.

11. The method of claim 10, wherein the CPE is preceded by second sidestream information, the second sidestream information having a smaller gap with the CPE than the first gap; the first gap is predefined, preconfigured, or network configured; the duration of the first gap takes on a value of 16 microseconds or 25 microseconds.

12. The method according to claim 10 or 11, wherein the CPEs comprise a first type of CPE and a second type of CPE, the first type of CPE being a CPE for which the first terminal device transmits a side line synchronization signal, the second type of CPE being a CPE for which the first terminal device transmits a side line shared channel, and a duration of the first type of CPE being different from a duration of the second type of CPE.

13. The method of claim 12, wherein the length of time of the first type of CPE is greater than the length of time of the second type of CPE.

14. The method of claim 13, wherein the method further comprises:

15. A method for transmitting a side-uplink synchronization signal block, comprising:

the second terminal equipment determines N time units in a first period according to the first configuration information, wherein N is an integer greater than 0, and the N time units are candidate time units for transmitting side uplink synchronous signal blocks;

the second terminal device fails to receive the side-link synchronization signal block in a first time unit of the N time units, or the number of time units in which the second terminal device fails to receive the side-link synchronization signal block in the N time units is greater than a first threshold, and the second terminal device receives the side-link synchronization signal block in a second time unit; the second time unit is located in the first period and is a time unit other than the N time units.

16. The method of claim 15, wherein the method further comprises:

17. The method of claim 15, wherein the method further comprises:

18. The method of claim 17, wherein the first side-link control information is further used to determine one or more of:

the location of the second time cell;

19. The method of any one of claims 15 to 18, wherein the second time unit is spaced a first duration from a first time unit or a last time unit of the N time units.

20. The method of claim 19, wherein the first duration is a duration configured by a network device;

or, the first duration is a preconfigured duration;

or, the first duration is a duration specified by a protocol.

21. The method of any one of claims 15 to 18, wherein a second time period is spaced between the first time unit and the second time unit.

22. The method of claim 21, wherein the second duration is a duration configured by a network device;

or, the second duration is a preconfigured duration;

or, the second duration is a duration specified by a protocol.

23. The method according to any one of claims 15 to 22, wherein an offset value between a starting point of a frequency domain resource occupied by the side uplink synchronization signal block and a starting point of a frequency domain resource of a channel occupied by the first terminal device is a first frequency domain offset value; the first frequency domain offset value is preset, or the first frequency domain offset value is determined for the first terminal device, or the first frequency domain offset value is configured for a network device.

24. The method according to any of claims 15 to 23, wherein the second time unit comprises first side line information, a third time unit preceding the second time unit comprises a cyclic prefix extension, CPE, the CPE and the first side line information being from the first terminal device, the third time unit and the second time unit being temporally adjacent, the CPE being of a first transmission duration.

25. The method of claim 24, wherein the CPE is preceded by second sidestream information, the second sidestream information having a smaller gap with the CPE than the first gap; the first gap is predefined, preconfigured, or network configured; the duration of the first gap takes on a value of 16 microseconds or 25 microseconds.

26. The method according to claim 24 or 25, wherein the CPEs comprise a first type of CPE and a second type of CPE, the first type of CPE being a CPE for which the first terminal device transmits a side line synchronization signal, the second type of CPE being a CPE for which the first terminal device transmits a side line shared channel, and a duration of the first type of CPE being different from a duration of the second type of CPE.

27. The method of claim 26, wherein the length of time of the first type of CPE is greater than the length of time of the second type of CPE.

28. The method of claim 27, wherein the method further comprises:

29. A first terminal device, comprising:

30. The first terminal device of claim 29, wherein the processing unit is further configured to:

31. The first terminal device of claim 29, wherein the transmitting unit is further configured to:

32. The first terminal device of claim 31, wherein the first side uplink control information is further used to determine one or more of:

the location of the second time cell;

33. The first terminal device of any of claims 29 to 32, wherein the second time unit is spaced a first duration from a first time unit or a last time unit of the N time units.

34. The first terminal device according to any of claims 29 to 33, wherein an offset value between a starting point of a frequency domain resource occupied by the side uplink synchronization signal block and a starting point of a frequency domain resource of a channel occupied by the first terminal device is a first frequency domain offset value; the first frequency domain offset value is preset, or the first frequency domain offset value is determined for the first terminal device, or the first frequency domain offset value is configured for a network device.

35. A second terminal device, comprising:

36. The second terminal device of claim 35, wherein the processing unit is further configured to:

37. The second terminal device according to claim 35, wherein the transmitting unit is further configured to:

first side uplink control information is received from the first terminal device, the first side uplink control information being used to determine the second time unit.

38. The second terminal device according to claim 37, wherein the first side uplink control information is further used to determine one or more of:

the location of the second time cell;

39. A second terminal device according to any of claims 35 to 38, wherein the second time unit is spaced a first time period from the first time unit or the last time unit of the N time units.

40. A communication device comprising a processor and a memory;

the processor being configured to execute a computer program or instructions stored in the memory to cause the communication device to implement the method of any one of claims 1 to 28.

41. A computer readable storage medium, characterized in that a computer program or instructions is stored which, when run on a computer, causes the computer to implement the method of any one of claims 1 to 28.

42. A chip comprising a processor coupled to a memory for executing a computer program or instructions stored in the memory, such that the chip implements the method of any one of claims 1 to 28.

43. A communication system, comprising: a first terminal device for implementing the method of any one of claims 1 to 14;

a second terminal device, the first terminal device being configured to implement the method of any of claims 15 to 28.