WO2023284692A1

WO2023284692A1 - Sidelink communication method, and terminal device

Info

Publication number: WO2023284692A1
Application number: PCT/CN2022/104984
Authority: WO
Inventors: Huei-Ming Lin
Original assignee: Guangdong Oppo Mobile Telecommunications Corp., Ltd.
Priority date: 2021-07-13
Filing date: 2022-07-11
Publication date: 2023-01-19

Abstract

Embodiments of methods and devices for sidelink communication are disclosed. In an example, a first terminal device generates a sidelink control channel and data according to a sub-slot length. The first terminal device transmits the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to a second terminal device. The plurality of sub-slots includes the first sub-slot.

Description

SIDELINK COMMUNICATION METHOD, AND TERMINAL DEVICE

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority to U.S. Provisional Patent Application No. 63/221,372 filed July 13, 2021, entitled “METHOD FOR SUB-SLOT TRANSMISSION IN SIDELINK COMMUNICATION, ” which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to communication technologies, and more particularly, to methods for sidelink communication and terminal devices, and computer-readable storage medium.

BACKGROUND

In the advancement of radio wireless technology for data exchange directly between two devices, also known as device-to-device (D2D) communication, it was first developed by 3rd generation partnership project (3GPP) and introduced in Release 12 (officially specified as sidelink communication) for Public Safety emergency uses such as mission critical communication to support low data rate and mainly voice type of connection. This sidelink communication system was originally developed base on the framework of 4th generation –long term evolution (4G-LTE) mobile cellular technology. During 3GPP Release 14 and 15, the sidelink technology was evolved to support vehicle-to-everything (V2X) communication as part of global development of intelligent transportation system (ITS) to boost road safety.

In Release 16, a new version of sidelink communication was developed in 3GPP but this time it was created base on the latest 5th generation –new radio (5G-NR) mobile cellular technology framework to support advanced V2X use cases requiring faster data rate, lower latency and higher reliability. Currently in Release 17, 3GPP is further enhancing the sidelink technology for better support of power constrained devices (e.g., mainly battery-operated terminals) by working on features to limit the amount of processing power required to operate sidelink and thus achieving power saving for the user equipment (UE) . At the same time, 3GPP is also working on improving communication reliability of the new NR sidelink (NR-SL) by means of exchanging coordination information between UEs in communication (also commonly known as inter-UE coordination) . Although 3GPP is constantly evolving and enhancing its sidelink technologies to support higher data transfer rate, strengthen its communication reliability and lowering the amount of processing power consumption, the aspect of shortening sidelink transmission latency, which is typically needed to support ultra-reliable and low latency communications (URLLC) for use cases and applications such as smart factory industrial internet of things (IIoT) , has not been well addressed so far.

Thus, how to improve data delivery latency over the sidelink is a problem to be solved.

SUMMARY

Embodiments of the present disclosure provide method for sidelink communication, terminal devices and computer-readable storage medium.

According to a first aspect, there is provided a sidelink communication method, including:

generating, by a first terminal device, a sidelink control channel and data according to a sub-slot length; and

transmitting, by the first terminal device, the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to a second terminal device, wherein the plurality of sub-slots includes the first sub-slot.

According to a second aspect, there is provided a sidelink communication method, including:

receiving, by a second terminal device, a sidelink control channel in at least a first sub-slot within a slot and data in a plurality of sub-slots within the slot from a first terminal device, wherein the plurality of sub-slots includes the first sub-slot, and the sidelink control channel and data is generated according to a sub-slot length; and

decoding, by the second terminal device, the data according to the sidelink control channel.

According to a third aspect, there is provided a terminal device configured to perform the method according to the first aspect or any implementation of the first aspect.

Specifically, the terminal device includes functional modules configured to perform the method according to the first aspect or any implementation of the first aspect.

According to a fourth aspect, there is provided a terminal device configured to perform the method according to the second aspect or any implementation of the second aspect.

Specifically, the terminal device includes functional modules configured to perform the method according to the second aspect or any implementation of the second aspect.

According to a fifth aspect, there is provided a terminal device including a processor and a memory configured to store a computer program, wherein the processor is used to call and run the computer program stored in the memory to perform the method according to the first aspect or any implementation of the first aspect.

According to a sixth aspect, there is provided a terminal device including a processor and a memory configured to store a computer program, wherein the processor is used to call and run the computer program stored in the memory to perform the method according to the second aspect or any implementation of the second aspect.

According to a seventh aspect, there is provided a chip configured to perform the method according to any one of the first to second aspects of any implementation of the first to second aspects.

Specifically, the chip includes a processor configured to call and run a computer program stored in a memory to cause a device in which the chip is installed to perform the method according to any one of the first to second aspects of any implementation of the first to second aspects.

According to an eighth aspect, there is provided a computer-readable storage medium configured to store a computer program, wherein the computer program is configured to cause a computer to perform the method according to any one of the first to second aspects of any implementation of the first to second aspects.

According to a ninth aspect, there is provided a computer program product including computer program instructions that cause a computer to perform the method according to any one of the first to second aspects of any implementation of the first to second aspects.

According to a tenth aspect, there is provided a computer program. When the computer program is run on a computer, the computer is caused to perform the method according to any one of the first to second aspects of any implementation of the first to second aspects.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments of the present disclosure and, together with the description, further serve to explain the principles of the present disclosure and to enable a person skilled in the pertinent art to make and use the present disclosure.

FIG. 1 and FIG. 2 are schematic diagrams of application scenarios according to embodiments of the present disclosure.

FIG. 3 is a flowchart of a sidelink communication method according to an embodiment of the present disclosure.

FIG. 4 shows an exemplary illustration of a proposed structure for sub-slot sidelink transmission with four OFDM symbols per sub-slot in a sidelink slot without Physical Sidelink Feedback Channel (PSFCH) resources according to an embodiment of the present disclosure.

FIG. 5 is an exemplary illustration of a proposed structure for sub-slot sidelink transmission with 3 OFDM symbols per sub-slot in a sidelink slot (pre-) configured with PSFCH resources according to an embodiment of the present disclosure.

FIG. 6 is a flowchart of a sidelink communication method according to an embodiment of the present disclosure.

FIG. 7 shows a schematic block diagram of a first terminal device according to an embodiment of the present disclosure.

FIG. 8 shows a schematic block diagram of a second terminal device according to an embodiment of the present disclosure.

FIG. 9 shows a schematic block diagram of a terminal device according to an embodiment of the present disclosure.

FIG. 10 is a schematic structural diagram of a chip according to an embodiment of the present disclosure.

Embodiments of the present disclosure will be described with reference to the accompanying drawings.

DETAILED DESCRIPTION

Although specific configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the pertinent art will recognize that other configurations and arrangements can be used without departing from the spirit and scope of the present disclosure. It will be apparent to a person skilled in the pertinent art that the present disclosure can also be employed in a variety of other applications.

It is noted that references in the specification to “one embodiment, ” “an embodiment, ” “an example embodiment, ” “some embodiments, ” “certain embodiments, ” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it would be within the knowledge of a person skilled in the pertinent art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

In general, terminology may be understood at least in part from usage in context. For example, the term “one or more” as used herein, depending at least in part upon context, may be used to describe any feature, structure, or characteristic in a singular sense or may be used to describe combinations of features, structures or characteristics in a plural sense. Similarly, terms, such as “a, ” “an, ” or “the, ” again, may be understood to convey a singular usage or to convey a plural usage, depending at least in part upon context. In addition, the term “based on” may be understood as not necessarily intended to convey an exclusive set of factors and may, instead, allow for existence of additional factors not necessarily expressly described, again, depending at least in part on context.

Various aspects of wireless communication systems will now be described with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, units, components, circuits, steps, operations, processes, algorithms, etc. (collectively referred to as “elements” ) . These elements may be implemented using electronic hardware, firmware, computer software, or any combination thereof. Whether such elements are implemented as hardware, firmware, or software depends upon the particular application and design constraints imposed on the overall system.

It should be understood that the technical solutions of embodiments of the present disclosure can be applied to various communication systems, such as: a Global System of Mobile communication (GSM) system, a Code Division Multiple Access (CDMA) system, a Wideband Code Division Multiple Access (WCDMA) system, a General Packet Radio Service (GPRS) system, a Long Term Evolution (LTE) system, a LTE Frequency Division Duplex (FDD) system, a LTE Time Division Duplex (TDD) system, a Universal Mobile Telecommunication System (UMTS) , a Worldwide Interoperability for Microwave Access (WiMAX) communication system, a New Radio (NR) system or a future 5G system, etc.

In particular, the technical solutions of embodiments of the present disclosure can be applied to various communication systems which are based on non-orthogonal multiple access technologies, for example, a Sparse Code Multiple Access (SCMA) system, a Low Density Signature (LDS) system, etc. The SCMA system and the LDS system can also be called other names in the communication field. Further, the technical solutions of embodiments of the present disclosure can be applied to a multi-carrier transmission system which uses non-orthogonal multiple access technology, for example, systems using Orthogonal Frequency Division Multiplexing (OFDM) , Filter Bank Multi-Carrier (FBMC) , Generalized Frequency Division Multiplexing (GFDM) , Filtered-OFDM (F-OFDM) , etc.

The terminal device in embodiments of the present disclosure can refer to User Equipment (UE) , access terminal, user unit, user station, mobile station, mobile device, remote station, remote terminal, mobile equipment, user terminal, terminal, wireless communication equipment, user agent or user device. The access terminal can be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA) , a handheld device with wireless communication functions, a computing device or other processing device connected to a wireless modem, an in-vehicle device, a wearable device, a terminal device in future 5G networks, or a terminal device in the future evolved Public Land Mobile Network (PLMN) , etc. Embodiments of the present disclosure do not impose specific limitations on this.

The network device in embodiments of the present disclosure may be a device used for communicating with a terminal device. The network device may be a base station (Base Transceiver Station, BTS) in a GSM system or a CDMA system, a base station (NodeB, NB) in a WCDMA system, an evolved base station (Evolutional Node B, eNB or eNodeB) in an LTE system, or a wireless controller in a Cloud Radio Access Network (CRAN) , or the network device may be a relay station, an access point, an on-vehicle device, a wearable device, a network device gNB in a future 5G network, or a network device in a future evolved PLMN, etc. Embodiments of the present disclosure do not impose specific limitations on this.

FIG. 1 and FIG. 2 are schematic diagrams of an application scenario of an embodiment of the present disclosure. FIG. 1 exemplarily shows one network device and two terminal devices. According to some embodiments, the wireless communication system may include multiple network devices and the coverage of each network device may include other numbers of terminal devices, and embodiments of the present disclosure do not impose specific limitations on this. In addition, the wireless communication system may further include other network entities such as Mobile Management Entity (MME) , Serving Gateway (S-GW) , Packet Data Network Gateway (P-GW) , etc. However, embodiments of the present disclosure are not limited to this.

Specifically, a terminal device 20 and a terminal device 30 may communicate with each other in a Device to Device (D2D) communication mode. When performing D2D communication, the terminal device 20 and the terminal device 30 directly communicate with each other via the D2D link, that is, the sidelink (SL) . For example, as shown in FIG. 1 or FIG. 2, the terminal device 20 and the terminal device 30 communicate directly through a sidelink. In FIG. 1, the terminal device 20 and the terminal device 30 communicate through the sidelink, and their transmission resources are allocated by a network device 10. In FIG. 2, the terminal device 20 and the terminal device 30 communicate through the sidelink, and transmission resources are autonomously selected by the terminal devices, and there is no need for the network device 10 to allocate transmission resources.

The D2D communication mode can be applied to Vehicle to Vehicle (V2V) communication or Vehicle to Everything (V2X) communication. In V2X communication, X can generally refer to any device with wireless transmission and reception capabilities, such as but not limited to slow-moving wireless devices, fast-moving vehicle-mounted devices, or network control nodes with wireless transmission and reception capabilities. It should be understood that embodiments of the present disclosure are mainly applied to the scenario of V2X communication, but can also be applied to any other D2D communication scenario, which is not limited in embodiments of the present disclosure.

LTE-V2X is standardized in Release-14 of the 3GPP protocol, and two transmission modes are defined, namely transmission mode 3 and transmission mode 4. Transmission resources for a terminal device using the transmission mode 3 are allocated by a base station, and the terminal device transmits data on the sidelink according to the resources allocated by the base station. The base station can allocate a resource for a single transmission to the terminal device, or the base station can allocate semi-static transmission resources to the terminal device. If a terminal device using the transmission mode 4 has a listening or sensing capability, the terminal device uses a sensing and reservation method to transmit data. If the terminal device does not have the listening or sensing capability, the terminal device randomly selects transmission resources from a resource pool. A terminal device having the listening or sensing capability obtains an available resource set from a resource pool by sensing, and the terminal device randomly selects a resource from the resource set for data transmission. Because the services in the Internet of Vehicles systems have periodic characteristics, terminal devices usually adopts semi-static transmissions. That is, after a terminal device selects a transmission resource, the terminal device will continue to use the resource in multiple transmission cycles, thereby reducing the probability of resource reselection and resource conflicts. The terminal device carries information to reserve resources for a next transmission in control information for the current transmission, so that other terminal devices can determine whether the resources are reserved and used by the terminal device by detecting the control information of the terminal device, and thus resource conflicts can be reduced.

In NR-V2X, autonomous driving needs to be supported, and thus higher requirements are put forward for data interaction between vehicles, such as higher throughput, lower delay, higher reliability, larger coverage, more flexible resource allocation, etc.

In the NR-V2X system, multiple transmission modes are introduced, such as mode 1 and mode 2. In mode 1, the network allocates sidelink transmission resources for terminals (similar to mode 3 in LTE-V2X) . In mode 2, the terminals select sidelink transmission resources.

In the existing design of NR-SL communication, transmission of a Media Access Control (MAC) Packet Data Unit (PDU) or Transport Block (TB) primarily followed a slot-based structure and time unit, which consists of 14 Orthogonal Frequency Division Multiplexing (OFDM) symbols, same as the one used in LTE-SL. That is, the NR-SL slot structure always begin with a OFDM symbol allocated for receiver Automatic Gain Control (AGC) purpose, followed by 12 usable symbols for transmitting sidelink control and data information, and the last symbol is designated as a gap period (GAP) for transmit (Tx) /receive (Rx) or sidelink /uplink switching.

Unlike NR downlink and uplink transmissions over the Uu interface, where the transmission scheduling powers for all UEs are precisely controlled by the base station (BS) gNB, SL transmissions from different UEs are unpredictable and it can greatly affect the AGC function to adjust receiver input level if SL transmitting UEs are not synchronized at the slot boundary and they do not have the same Tx duration. As such, the concept of mini-slot transmission occupying only a few OFDM symbols within a slot that had already been used in NR downlink and uplink for short latency communication still has not been adopted in NR-SL yet.

So far, only the slot-based transmission is supported in NR-SL communication. That is, a MAC PDU or TB is channel encoded, modulated, transmitted across a slot, and a reception UE must receive and perform data decoding for the entire slot (or at least the useful 12 OFDM symbols) before it can extract the encoded data information. This means the time interval for the initial transmission or retransmission of a MAC PDU or TB currently in the NR-SL communication is one slot. The exact time duration of a NR-SL slot is dependent on the sub-carrier spacing (SCS) configured and used for the SL bandwidth part (BWP) . For SL operation in frequency range 1 (FR1) (i.e., 410 MHz to 7125 MHz spectrum) , the slot duration is 1, 0.5 and 0.25ms for 15, 30 and 60KHz configured SCS, respectively. If max number of 32 SL retransmissions is used, it will take at least 8ms of back-to-back transmissions to complete delivery of one MAC PDU or TB the at the radio layer, assuming full availability of resources. For a typical URLLC service requiring 3 to 10ms end-to-end latency (such as fully autonomous driving, extended sensors sharing, platooning in V2X, and augmented reality (AR) /virtual reality (VR) gaming with head mounted display) , the current NR-SL transmission design simply cannot fulfill this packet delay budget (PDB) . And hence, further enhancement on NR-SL transmission design is needed in order to support use cases and deployment that require such an ultra-low latency communication.

In embodiments of the present disclosure, a proposed method for sub-slot transmission in sidelink (SL) communication is provided. FIG. 3 is a flowchart of a sidelink communication method according to an embodiment of the present disclosure. The method may be applied in a sidelink communication between a first terminal device (e.g., a transmitter UE, or a Tx-UE) and a second terminal device (e.g., a receiver UE, or a Rx-UE) . The method may include the following steps:

In step 301, the first terminal device generates a sidelink control channel and data according to a sub-slot length.

The sub-slot length refers to the length of a sub-slot in a slot, or in other words, the interval of a sub-slot (SS-TI) in a slot. For example, the sub-slot length may be 2, 3, 4, or 6 OFDM symbols. The slot may include more than one sub-slot.

In step 302, the first terminal device transmits the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to the second terminal device. The plurality of sub-slots includes the first sub-slot.

In the embodiment, the slot is divided into multiple sub-slots, the sidelink control channel is transmitted in at least the first sub-slot in the slot, and data is transmitted in the multiple sub-slots which include the first sub-slot. The data transmitted in the first sub-slot is the initial transmission of the data, and the data transmitted in the remaining sub-slots can be considered as the retransmissions of the data. After receiving the sidelink control channel and the data in the first sub-slot, the second terminal can decode the data according to the sidelink control channel (the sidelink control channel may carry control information for decoding the data) . Since the sidelink control channel and data is generated according to the sub-slot length, the sidelink control channel and the data can be transmitted within the sub-slot length (e.g., 2, 3, 4, or 6 OFDM symbols) . That is, the sidelink communication method in the embodiment uses smaller number of OFDM symbols in a slot for sidelink communication, thereby reducing the total time duration to complete the delivery of data information over the sidelink and accordingly improving data delivery latency over the sidelink and supporting use cases and deployment that require ultra-low latency communication.

According to some embodiments, each of the sub-slots may be configured or preconfigured as including a smaller number of OFDM symbols than the total number of OFDM symbols in a slot (i.e., 14 OFDM symbols) . For example, a set of possible values for the sub-slot length are 2, 3, 4 or 6 OFDM symbols.

FIG. 4 shows an exemplary illustration of a proposed structure for sub-slot sidelink transmission with four OFDM symbols per sub-slot in a sidelink slot without Physical Sidelink Feedback Channel (PSFCH) resources.

Different to the current symbol-based downlink and uplink transmission scheme adopted on NR Uu interface where the same TB is only transmitted once before a receiving a Hybrid Automatic Repeat reQuest (HARQ) feedback report, the proposed sub-slot SL transmission occupies only a few OFDM symbols for the initial transmission or a retransmission of data (for example, a MAC PDU or TB) and the same MAC PDU or TB is retransmitted several times within a slot to improve reliability until the useful part of the SL slot is fully utilized.

Further, unlike mini-slot transmission over the Uu interface where transmission for a UE is shorter than a slot duration and UE transmission timing in a slot is variable, the (re) transmissions of same MAC PDU or TB in embodiments of the present disclosure span the whole SL slot, in other words, the (re) transmissions of same MAC PDU or TB last for the whole SL slot duration. This means that SL transmitting UEs can be synchronized at the slot boundary, and the AGC function is not affected.

As shown in FIG. 4, a slot includes 14 OFDM symbols. The first OFDM symbol is one symbol for receiver AGC training purpose. The last OFDM symbol is one OFDM symbol for Tx/Rx switching gap. There are 12 useable OFDM symbols for transmitting a control channel and data. That is, the 12 useable OFDM symbols can be considered as the useful part of the SL slot. In the slot structure shown in FIG. 4, there is no (pre-) configured PSFCH resources.

The sidelink control channel may include a Physical Sidelink Control Channel (PSCCH) . The data may be carried in a data channel which may include a Physical Sidelink Shared Channel (PSSCH) . The PSCCH carries control information for decoding the data channel. For example, the PSCCH may carry a first stage Sidelink Control Information (SCI) .

The OFDM symbols of the SL slot structure that can be used for transmitting PSCCH and PSSCH (i.e., 12 out of 14 symbols in a slot contains no PSFCH resources) are divided into 2 or more sub-slot transmit intervals (SS-TIs) . In the example of FIG. 4, the useful part of the slot is divided into 3 sub-slots. Each of the sub-slots is used for transmitting the PSCCH/PSSCH or just the PSSCH to deliver the initial transmission or a re-transmission of a MAC PCU or TB.

During the process of transmitting the same MAC PDU or TB several times within a SL slot, the PSCCH, which carries 1st stage sidelink control information (SCI) , is transmitted at least once in the first sub-slot of the slot using Physical Resource Blocks (PRBs) according to the existing PSCCH mapping and transmission method. As such, SL resource assignment and reservation information for the current transmission and future SL resource slots encoded in the first stage SCI can be still be obtained by earlier release UEs operating in the same SL resource pool.

According to some embodiments, besides the first sub-slot, the same PSCCH could be also transmitted in other sub-slots than the first sub-slot within the same slot for enhancing decoding performance of PSCCH for receiver UEs by combining the multiple PSCCH transmissions.

According to some other embodiments, the PSCCH is transmitted only in the first sub-slot, such that more PRBs are allocated for PSSCH transmission to lower the coding rate and thus improving the performance of PSSCH instead.

The starting position of the first sub-slot within a sidelink slot may be always from the second OFDM symbol in the sidelink slot. The ending position for the last sub-slot within the sidelink slot depends on at least the PSFCH) resources allocation. For example, if PSFCH resources are not (pre-) configured in the sidelink slot, the ending position (the last symbol) for the last sub-slot is the second last symbol of the slot. Otherwise, if PSFCH resources are (pre-) configured in the sidelink slot, the ending position (the last symbol) for the last sub-slot is the tenth symbol of the slot, where the subsequent three symbols are allocated due to PSFCH operation (as shown in FIG. 5 which will be described later) .

FIG. 4 is described using 4 symbols per sub-slot as an example. In other examples, the sub-slot length and the number of sub-slots may vary. The length of a sub-slot (i.e., sub-slot length) and number of sub-slots that can be used for the proposed sub-slot SL transmission are correlated with each other. That is, if the length of a sub-slot is short (e.g., 2 or 3 symbols) , the higher number of sub-slots can be allocated and used for re-transmission (s) of a MAC PDU or TB in a sidelink slot. Assuming the sub-slot has a length of 3 OFDM symbols in a sidelink slot and no PSFCH resources are (pre-) configured for the slot, this means a total of 12 useable symbols for PSCCH/PSSCH transmissions and 4 sub-slots can be allocated for sub-slot SL transmission. As another example, when the sub-slot length is 6 symbols, there can be only 2 sub-slots in a slot. For a sidelink slot with PSFCH resource (pre-) configured with total of 9 useable symbols for PSCCH/PSSCH transmission, in this case the total number of sub-slots is 3 for the slot when a length of 3 symbols is allocated per sub-slot.

Referring to FIG. 4, when the sub-slot length is 4 symbols, this means there are 3

sub-slot opportunities

101, 102 and 103 for SL transmission within the slot. For a slot-based resource assignment 100, which could be allocated by a sidelink Tx-UE’s serving base station (BS) gNB (e.g., as part of NR-SL mode 1 operation) or selected autonomously by the Tx-UE on its own based on channel sensing (e.g., as part of NR-SL mode 2 operation) .

The Tx-UE generates the sidelink control channel and the data according to the sub-slot length. For example, the Tx-UE prepares the first stage SCI, encodes the first stage SCI into a PSCCH 104, and separately encodes a PSSCH 105 containing also a second stage SCI to deliver a sidelink data (e.g., MAC PDU or TB) according to the sub-slot length. The PSCCH 104 and the PSSCH 105 may also be prepared according to the number of frequency sub-channels.

According to some embodiments, transmitting the data (e.g., MAC PDU or TB) in the plurality of sub-slots within the slot, includes:

performing an initial transmission of the data to the Rx-UE in the first sub-slot; and

performing at least one retransmission of the data in at least one remaining sub-slots other than the first sub-slot in the slot, wherein each of the at least one retransmission of the data is associated with a different redundancy version which is included in a corresponding second stage Sidelink Control Information (SCI) .

As shown in FIG. 4, the encodings of PSCCH and its associated PSSCH (including the second stage SCI) are for the SL transmission in the first sub-slot opportunity 101. For the second sub-slot opportunity 102, the PSSCH 106 is re-encoded for a re-transmission of the same MAC PDU or TB and possibly with different redundancy version since the total number of available resource elements is more than the first sub-slot from the absence/no repetition of PSCCH. In the third sub-slot opportunity 103, although the sub-slot length and number of frequency sub-channels are the same as for the second sub-slot, the PSSCH 107 is re-encoded again for another re-transmission of the same MAC PDU or TB, and also with another redundancy version in the second stage SCI.

FIG. 5 is an exemplary illustration of a proposed structure for sub-slot sidelink transmission with 3 OFDM symbols per sub-slot in a sidelink slot (pre-) configured with PSFCH resources. For the illustrated slot structure, in addition to the one OFDM symbol reserved at the beginning and at the end of a SL slot, further 3 symbols preceding to the last OFDM symbol in the slot are allocated for the operation of PSFCH: one symbol for Tx/Rx switching gap, one symbol for AGC training purpose and another one symbol for the actual PSFCH transmission. This leaves remaining 9 useable OFDM symbols for transmitting PSCCH and PSSCH in the slot.

When the sub-slot length is 3 symbols long, this gives 3

sub-slot opportunities

201, 202 and 203 for SL transmission within the slot. For the first sub-slot opportunity 201, similar to the exemplary illustration 101 in the slot-based resource assignment 100 the Tx-UE prepares the first stage SCI, encodes it into a PSCCH 204, and separately encodes a PSSCH 207 containing also a second stage SCI to deliver a sidelink data (e.g., MAC PDU or TB) according to the sub-slot length. The preparation of the PSCCH 204 and the PSSCH 207 may also be made according to the number of frequency sub-channels.

To improve PSCCH decoding performance of new release UEs that are capable of receiving the proposed sub-slot SL transmissions, the entire encoded PSCCH 204 is repeated and transmitted in the remaining sub-slots of the slot, as shown in 205 and 206.

On the other hand, PSSCH encoding of the same MAC PDU or TB and the second stage SCI for SL transmission in the three sub-slot opportunities could be done separately for different redundancy versions. As such, the encoded

PSSCH

208 and 209 are each a re-transmission of the PSSCH 207 with a different redundancy version. The redundancy versions used in

PSSCH

208 and 209 could be also different.

According to some embodiments, transmitting of the sidelink control channel and the data to the second terminal device includes: transmitting, by the first terminal device, the sidelink control channel in a first frequency domain resource, and transmitting a sidelink data channel carrying the data in a second frequency domain resource that is separated from the frequency domain resource in a frequency domain. For example, as can be seen from FIG. 5, the transmission of PSCCH and PSSCH during the useable part of the SL slot for control information and data in diagram 200 is completely separated in the frequency domain. The PSCCH is transmitted in the first sub-channel in the frequency domain, but the PSCCH may not always occupy the whole first sub-channel. When the size of a sub-channel is configured as very large (for example, the PSCCH does not use all PRBs in the first sub-channel) , remaining PRBs other than the PRBs for transmitting the PSCCH can be used for transmitting the PSSCH.

One benefit of this transmission separation in the frequency domain is allowing separate Tx power allocation/boosting for the sidelink control and data channels to achieve different level of QoS and reliability. If higher data delivery reliability is needed and/or the data encoding rate for the PSSCH is high, more Tx power can be allocated to the PSSCH transmission to ensure better decoding performance. On the other hand, if PSCCH need more protection, more Tx power is allocated to the PSCCH transmissions. According to some embodiments, a power for transmitting the sidelink control channel is different from a power for transmitting the sidelink data channel.

In order to differentiate between SL transmission with legacy slot structure (i.e., using the entire useable 12 OFDM symbols for a single SL transmission as per earlier release UE behavior) and the newly proposed sub-slot SL structure (i.e., containing multiple SL transmissions in a slot) such that new release UEs would be able to determine the length of OFDM symbols for PSSCH decoding and possibly to also perform PSCCH combining (when PSCCH is transmitted in other than the first sub-slot) , the first stage SCI may include indication information which is used to indicate whether sub-slot sidelink transmission is applied and/or the sub-slot length.

As an example, a new parameter field with 1 or 2 bits can be defined for the first stage SCI (e.g., by reusing some of the existing reserved bits in SCI format 1-A) to indicate whether sub-slot SL transmission is applied and/or sub-slot length used (i.e., number of OFDM symbols used per sub-slot) in the current SL resource.

By indicating the sub-slot transmission and/or the sub-slot length as part of first stage SCI in PSCCH, the receiver UE would then be able to determine the allocation (position and length) of the associated PSSCH for data decoding and combining. Without this indication in SCI, the receiver UE would assume and attempt to decode PSSCH according to the common slot-based SL transmission as per earlier release UEs.

If the new parameter field is defined using just 1 bit, it is used to indicate whether sub-slot SL transmission is applied in the current SL resource slot. If 2-bits are defined, it is used to indicate the sub-slot length. One example of such indication for sub-slot length may be as follows:

· Bit pattern {0 1} indicates sub-slot length of 3 OFDM symbols

· Bit pattern {1 0} indicates sub-slot length of 4 OFDM symbols

· Bit pattern {1 1} indicates sub-slot length of 6 OFDM symbols

Alternatively, if a set of possible sub-slot lengths that can be used for sub-slot SL transmissions is (pre-) configured for the resource pool, the bit pattern for the new parameter in the first stage SCI could be used to indicate the index of the (pre-) configured sub-slot length.

If more SL resource (s) other than the current slot is reserved in the first stage SCI for further re-transmissions of the same MAC PDU or TB, the receiver UE can assume sub-slot SL transmissions will be also applied and perform combining of the received PSSCHs and possibly PSCCHs in the reserved resources based on the indicated sub-slot length.

For the proposed sub-slot based SL transmission, although it is not intended for SL UEs implemented based on earlier releases of SL technology, some certain basic settings/parameters for proper functioning of the feature are needed to be aligned among the UEs.

In order to align common settings between transmitter and receiver UEs to ensure proper operation of sub-slot SL transmission, and also to minimize PSCCH blind decoding complexity for UEs operating in the same resource pool, one or more of the following parameters/settings could be configured to the UEs, for example through higher layer signaling (RRC configuration) , or could be pre-configured to the UEs (RRC pre-configuration) :

· One or more sub-slot lengths that can be used by a UE for sub-slot SL transmission. A set of possible values for the sub-slot length could be (pre-) configured are 2, 3, 4 and 6 OFDM symbols. This (pre-)configuration parameter would allow SL Tx-UE to flexibly select an appropriate sub-slot length based on packet latency requirement, data packet size, and/or number of re-transmissions per MAC PDU or TB.

· Whether PSCCH is to be included in every sub-slot within a transmitted resource slot. This parameter is important to pre-align receiver UE’s assumption on whether PSCCH is transmitted only in the first or in all of the sub-slot within a slot. When this parameter is set to enabled, a SL receiver UE will attempt to combine PSCCH from multiple sub-slots within a slot to improve the decoding performance, if PSCCH decoding attempt is unsuccessful during the first sub-slot of a slot.

· A sub-set of resources within a resource pool that can be used by UE for sub-slot SL transmission.

This could be a sub-pool or a portion of resources within a resource pool, for example (pre-)configured as SL Type 1 or Type 2 configured grant resources.

According to some embodiments, transmitting, by the first terminal device, the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to a second terminal device includes:

selecting resources from a sub-set of resources within a resource pool, wherein the sub-set of resources are configured or pre-configured as allowing sub-slot transmission; and

transmitting, by the first terminal device, the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to the second terminal device using the selected resources.

Only within the (pre-) configured sub-set of resources within the resource pool, a SL transmitting UE is allowed to perform sub-slot SL transmissions. Similarly, a SL reception UE will only attempt to combine /decode PSCCH and PSSCH within the (pre-) configured sub-set of resources to minimize receiver processing complexity and power consumption. And therefore, if the UE is decided to perform sub-slot SL transmissions, it should restrict the selection of resources to be within the (pre-) configured sub-set of resources.

In view of the above, embodiments of the present disclosure may have at least the following technical effects.

In order to improve data delivery latency over the sidelink PC5 interface, the transmit time interval for the initial and re-transmissions of a SL MAC PDU or TB in physical layer is shortened to a sub-slot level, such that it allows a receiver UE to be able to perform data information decoding of PSSCH channel earlier than the current SL communication.

In the existing SL slot structure without any (pre-) configured PSFCH resources, there are 12 OFDM symbols can be used for transmitting PSCCH and PSSCH. In existing technologies, the PSCCH is transmitted in the first 2 or 3 OFDM symbols, carrying time and frequency resource assignment information for the current and future transmissions of a MAC PDU or TB. The resource allocation for PSCCH can be up to max of 1 sub-channel in the frequency domain, but resource allocation for PSSCH transmission can be more than 1 sub-channel and spanning across all 12 useable symbols. In the proposed sub-slot based SL transmission, the useable part of the slot (e.g., 12 symbols) is divided into multiple sub-slots and the transmit interval of a sub-slot could be (pre-) configured to be 2, 3, 4, or 6 OFDM symbols. As such, there could be 6, 4, 3, or 2 (re-)transmissions of the same MAC PDU or TB within a SL slot of 14 symbols. A receiver UE starts PSSCH decoding at the end of the first sub-slot, and hence the data delivery can be up to about 6 times faster than the current SL communication.

In order to allow the proposed sub-slot SL transmission to coexist with the legacy slot-based SL operation in a same resource pool, PSCCH of the new sub-slot scheme is at least transmitted in the first sub-slot opportunity using the same PSCCH resource allocation currently defined, such that it is still receivable and decodable by legacy UEs. To improve its decoding performance, PSCCH may be repeated and transmitted in the remaining sub-slots as well in a slot, providing additional combining gain for receiver UEs. Furthermore, when PSCCH is transmitted in all sub-slots within a slot, transmit power boosting can be applied to either PSCCH or PSSCH to enhance decoding performance.

Further, the sidelink communication method proposed in embodiments of the present disclosure retains its backward compatibility to earlier UE implementation according to previous releases of NR-SL technology, since the format structure of first stage sidelink control information (SCI) and the resource allocation for sidelink control channel, sidelink feedback channel and AGC/Gap symbols are able to remain the same within a slot.

Also, the sidelink communication method proposed in embodiments of the present disclosure retains results in less congestion of SL transmissions due to re-transmission (s) of the same MAC PDU or TB are sent within the same slot. For example, if the same MAC PDU or TB can be (re-) transmitted six times within the same slot, then it will require only 5 slots to complete a total of 30 (re-) transmissions.

Lastly, to minimize receiver processing complexity and UE power consumption in detecting and decoding sub-slot based SL transmissions, a sub-set of one or more of all possible sub-slot lengths is (pre-)configured such that a receiver UE does not need to blindly combine and decode all possible PSCCH locations due to different sub-slot length. Moreover, the SL resources in which the proposed sub-slot based SL transmission can be performed by a SL transmitting UE is further restricted within a sub-set of resources within a SL resource pool by (pre-) configuration. As such, it further limits the number of PSCCH blind decodes that a receiver UE needs to perform to only within a confined sub-set of resources within a pool.

The above embodiments are described from the perspective of the first terminal device (e.g., a transmitter UE, or a Tx-UE) . The following will describe embodiments from the perspective of the second terminal device (e.g., a receiver UE, or a Rx-UE) .

FIG. 6 is a flowchart of a sidelink communication method according to an embodiment of the present disclosure. The method may include the following steps:

In step 601, the second terminal device receives a sidelink control channel in at least a first sub-slot within a slot and data in a plurality of sub-slots within the slot from a first terminal device. The plurality of sub-slots includes the first sub-slot, and the sidelink control channel and data is generated according to a sub-slot length.

In step 602, the second terminal device decodes the data according to the sidelink control channel.

According to some embodiments, a starting position of the first sub-slot is the second symbol in the slot.

According to some embodiments, an ending position of a last sub-slot in the slot is associated with at least Physical Sidelink Feedback Channel (PSFCH) resources allocation.

According to some embodiments, the sidelink control channel is further received in other sub-slots than the first sub-slot in the slot.

According to some embodiments, the method further includes: performing, by the second terminal device, channel combing on the sidelink control channel which is received in all sub-slots in the slot.

According to some embodiments, receiving of the data in the plurality of sub-slots within the slot, includes:

receiving, by the second terminal device, the data as an initial transmission in the first sub-slot; and

receiving, by the second terminal device, the data as at least one retransmission in at least one remaining sub-slots other than the first sub-slot in the slot, wherein each of the at least one retransmission of the data is associated with a different redundancy version which is included in a corresponding second stage Sidelink Control Information (SCI) .

According to some embodiments, the sidelink control channel includes first stage Sidelink Control Information (SCI) , and the first stage SCI includes indication information which is used to indicate whether sub-slot sidelink transmission is applied and/or the sub-slot length;

wherein the method further includes:

determining, by the second terminal device, a position and a length of a data channel carrying the data according to the indication;

wherein decoding of the data further includes:

decoding the data channel to obtain the data according to the position and length of the data channel.

According to some embodiments, the indication information includes at least one bit to indicate the sub-slot length, or an index corresponding to the sub-slot length.

According to some embodiments, receiving of the sidelink control channel and data includes:

receiving, by the second terminal device, the sidelink control channel in a first frequency domain resource, and receiving a sidelink data channel carrying the data in a second frequency domain resource that is separated from the first frequency domain resource in a frequency domain.

According to some embodiments, a power for transmitting the sidelink control channel is different from a power for transmitting the sidelink data channel.

The sidelink communication methods according to embodiments of the present disclosure are described in detail above, and terminal devices according to embodiments of the present disclosure will be described below with reference to FIG. 7 to FIG. 8. The technical features described in the method embodiments are applicable to the following device embodiments.

FIG. 7 shows a schematic block diagram of a first terminal device 700 according to an embodiment of the present disclosure. As shown in FIG. 7, the terminal device 700 includes a generation module 710 and a transmitting module 720.

The generation module 710 is configured to generate a sidelink control channel and data according to a sub-slot length.

The transmitting module 720 is configured to transmit the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to a second terminal device, wherein the plurality of sub-slots includes the first sub-slot.

According to some embodiments, the sidelink control channel is further transmitted in other sub-slots than the first sub-slot in the slot.

According to some embodiments, the transmitting module 720 is configured to:

perform an initial transmission of the data to the second terminal in the first sub-slot; and

perform at least one retransmission of the data in at least one remaining sub-slots other than the first sub-slot in the slot, wherein each of the at least one retransmission of the data is associated with a different redundancy version which is included in a corresponding second stage Sidelink Control Information (SCI) .

According to some embodiments, the generation module 710 is configured to:

encode first stage Sidelink Control Information (SCI) into the sidelink control channel, wherein the first stage SCI includes indication information which is used to indicate whether sub-slot sidelink transmission is applied and/or the sub-slot length.

According to some embodiments, the first terminal device further includes:

an obtaining module configured to obtain information regarding one or more sub-slot lengths that can be used by the first terminal for sub-slot sidelink transmission;

wherein the generating module 710 is configured to:

select a sub-slot length from the one or more sub-slot lengths according to at least one of a packet latency requirement, a data packet size and number of retransmissions per MAC PDU or TB; and

generate the sidelink control channel and the data according to the selected sub-slot length.

According to some embodiments, the transmitting module 720 is configured to:

transmit the sidelink control channel in a first frequency domain resource, and transmitting a sidelink data channel carrying the data in a second frequency domain resource that is separated from the first frequency domain resource in a frequency domain.

According to some embodiments, a power for transmitting the sidelink control channel is different from a power for transmitting the sidelink data channel in the sub-slots is incrementally increased.

According to some embodiments, the first terminal device further includes:

an obtaining module configured to obtain configuration of whether physical sidelink control channel is to be transmitted in the first sub-slot or all sub-slots in the slot.

According to some embodiments, whether sidelink control channel is to be transmitted in the first sub-slot or all sub-slots in the slot is pre-configured.

According to some embodiments, the transmission module 720 is configured to:

select resources from a sub-set of resources within a resource pool, wherein the sub-set of resources are configured or pre-configured as allowing sub-slot transmission; and

transmit the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to the second terminal device using the selected resources.

It should be understood that the first terminal device 700 according to embodiments correspond to the terminal device described in the method embodiments, and modules in the first terminal device 700 are used to implement the above and other operations and/or functions implemented by the terminal device in the method in FIG. 3. For the sake of brevity, details are not described herein again.

FIG. 8 shows a schematic block diagram of a second terminal device 800 according to an embodiment of the present disclosure. As shown in FIG. 8, the second terminal device 800 includes a receiving module 810 and a decoding module 820.

The receiving module 810 is configured to receive a sidelink control channel in at least a first sub-slot within a slot and data in a plurality of sub-slots within the slot from a first terminal device. The plurality of sub-slots includes the first sub-slot, and the sidelink control channel and data is generated according to a sub-slot length.

The decoding module 820 is configured to decode the data according to the sidelink control channel.

According to some embodiments, the second terminal device further includes:

a channel combination module configured to perform channel combing on the sidelink control channel which is received in all sub-slots in the slot.

According to some embodiments, the receiving module is configured to:

receive the data as an initial transmission in the first sub-slot; and

receive the data as at least one retransmission in at least one remaining sub-slots other than the first sub-slot in the slot, wherein each of the at least one retransmission of the data is associated with a different redundancy version which is included in a corresponding second stage Sidelink Control Information (SCI) .

wherein the method further includes:

a determination module configured to determine a position and a length of a data channel carrying the data according to the indication;

wherein the decoding module is further configured to:

decode the data channel to obtain the data according to the position and length of the data channel.

According to some embodiments, the receiving module 810 is configured to:

receive the sidelink control channel in a first frequency domain resource, and receiving a sidelink data channel carrying the data in a second frequency domain resource that is separated from the first frequency domain resource in a frequency domain.

According to some embodiments, power for transmitting the sidelink control channel is different from a power for transmitting the sidelink data channel.

It should be understood that the second terminal device 800 according to embodiments correspond to the terminal device described in the method embodiments, and units in the terminal device 800 are used to implement the above and other operations and/or functions implemented by the terminal device in the method in FIG. 6. For the sake of brevity, details are not described herein again.

As shown in FIG. 9, an embodiment of the present disclosure further provides a terminal device 900. The terminal device 900 may be the terminal device 700 in FIG. 7, which can be used to perform the steps of the terminal device corresponding to the method in FIG. 3. The terminal device 900 may also be the terminal device 800 in FIG. 8, which can be used to perform the steps of the terminal device corresponding to method in FIG. 6. The terminal device 900 shown in FIG. 9 includes a processor 910, and the processor 910 can call and run a computer program from the memory to implement the methods according to embodiments of the present disclosure.

According to embodiments, as shown in FIG. 9, the terminal device 900 may further include a memory 920. The processor 910 may call and run a computer program from the memory 920 to perform the methods in embodiments of the present disclosure.

The memory 920 may be a separate device independent of the processor 910, or may be integrated in the processor 910.

According to embodiments, as shown in FIG. 9, the terminal device 900 may further include a transceiver 930, and the processor 910 may control the transceiver 930 to communicate with other devices. Specifically, the transceiver may send information or data to other devices, or receive information or data sent by other devices.

The transceiver 930 may include a transmitter and a receiver. The transceiver 3030 may further include one or more antennas.

According to embodiments, the terminal device 900 may specifically be the terminal device according to an embodiment of the present disclosure, and the terminal device 900 may implement the corresponding processes implemented by the terminal device in the method embodiments of the present disclosure. For brevity, details are not repeated here.

In a specific implementation, the generation module in the terminal device 700 and the decoding module in the terminal device 800 may be implemented by the processor 910 in FIG. 9. The transmitting module in the terminal device 700 and the receiving module in the terminal device 800 may be implemented by the transceiver 930 in FIG. 9.

FIG. 10 is a schematic structural diagram of a chip according to an embodiment of the present disclosure. The chip 1000 shown in FIG. 10 includes a processor 1010, and the processor 1010 can call and run a computer program from a memory to implement the method according to embodiments of the present disclosure.

According to embodiments, as shown in FIG. 10, the chip 1000 may further include a memory 1020. The processor 1010 may call and run a computer program from the memory 1020 to implement the method according to embodiments of the present disclosure.

The memory 1020 may be a separate device independent of the processor 1010, or may be integrated in the processor 1010.

According to embodiments, the chip 1000 may further include an input interface 1030. The processor 1010 may control the input interface 1030 to communicate with other devices or chips, and specifically, the processor 1010 can control the input interface to obtain information or data sent by other devices or chips.

According to embodiments, the chip 1000 may further include an output interface 1040. The processor 1010 can control the output interface 1040 to communicate with other devices or chips, and specifically, the processor 1010 can control the output interface 1040 to output information or data to other devices or chips.

According to embodiments, the chip can be applied to the terminal device in embodiments of the present disclosure, and the chip can implement the corresponding processes implemented by the terminal device in various methods according to embodiments of the present disclosure. For brevity, details are not repeated herein again.

It should be understood that the chip in the embodiments of the present disclosure may also be referred to as a system-level chip, a system chip, a chip system, or a system-on-chip, etc.

It should be understood that the terms “system” and “network” herein are often used interchangeably. The term “and/or” is only an association relationship describing associated objects, which means that there can be three kinds of relationships, for example, A and/or B can mean three situations: A alone, B alone, and A and B together. In addition, the character “/” herein generally indicates that the associated objects before and after “/” are in an “or” relationship.

It should be understood that the processor in embodiments of the present disclosure may be an integrated circuit chip with signal processing capability. In implementations, the steps of the foregoing method embodiments can be completed by hardware integrated logic circuits in the processor or instructions in the form of software. The above-mentioned processor may be a general-purpose processor, a Digital Signal Processor (DSP) , an Application Specific Integrated Circuit (ASIC) , a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component. The methods, steps, and logical block diagrams disclosed in the embodiments of the present disclosure can be implemented or executed. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor or the like. The steps of the methods disclosed in the embodiments of the present disclosure may be directly embodied as being executed and completed by a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, register. The storage medium is located in the memory, and the processor reads the information in the memory to perform the steps of the above methods in combination with hardware.

It can be understood that the memory in the embodiments of the present disclosure may be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory can be Read-Only Memory (ROM) , Programmable ROM (PROM) , Erasable PROM (EPROM) , Electrically EPROM (EEPROM) or flash memory. The volatile memory may be a Random Access Memory (RAM) , which is used as an external cache. By way of exemplary rather than limitation, many forms of RAM are available, such as Static RAM (SRAM) , Dynamic RAM (DRAM) , Synchronous DRAM (SDRAM) , Double Data Rate SDRAM (DDR SDRAM) , Enhanced SDRAM (ESDRAM) , Synchlink DRAM (SLDRAM) ) , or Direct Rambus RAM (DR RAM) . It should be noted that the memory in the systems and methods described in the present disclosure is intended to include but not limited to these and any other suitable types of memory.

It should be understood that the foregoing memory is exemplary but not restrictive. For example, the memory in embodiments of the present disclosure may also be Static RAM (SRAM) , Dynamic RAM (DRAM) , Synchronous DRAM (SDRAM) , Double Data Rate SDRAM (DDR SDRAM) , Enhanced SDRAM (ESDRAM) , Synchlink DRAM (SLDRAM) , or Direct Rambus RAM (DR RAM) , and so on. That is to say, the memory in embodiments of the present disclosure is intended to include but not limited to these and any other suitable types of memory.

An embodiment of the present disclosure also provides a computer-readable storage medium for storing computer programs.

According to embodiments, the computer-readable storage medium may be applied to the terminal device in embodiments of the present disclosure, and the computer programs cause a computer to perform the corresponding processes implemented by the terminal device in each method embodiment of the present disclosure. For brevity, repeated descriptions are omitted here.

An embodiment of the present disclosure provides a computer program product, including computer program instructions.

According to embodiments, the computer program product may be applied to the terminal device in embodiments of the present disclosure, and the computer program instructions cause a computer to perform the corresponding processes implemented by the terminal device in each method embodiment of the present disclosure. For brevity, repeated descriptions are omitted here.

An embodiment of the present disclosure also provides a computer program.

According to embodiments, the computer program may be applied to the terminal device in embodiments of the present disclosure, and when the computer program runs on a computer, the computer is caused to perform the corresponding processes implemented by the terminal device in each method embodiment of the present disclosure. For brevity, repeated descriptions are omitted here.

Those of ordinary skill in the art will appreciate that the exemplary units and algorithm steps described according to embodiments disclosed herein can be carried out by electronic hardware or a combination of electronic hardware and computer software. Whether the functions are implemented by hardware or software depends on particular applications and design constraints of the technical solutions. For each of the particular applications, a person skilled in the art can use different methods to implement the described functions, but such implementation should not be considered as beyond the scope of the present disclosure.

It may be clearly understood by those skilled in the art that details of specific operation procedures of the systems, devices and units can be found in the previous description regarding the method embodiments.

In the embodiments provided in the present disclosure, it should be understood that the disclosed systems, devices and methods may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a kind of logical function division. In practice, other division manner may be used. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not performed. In addition, the illustrated or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.

The units described as separated parts may or may not be physically separated, and the parts displayed as units may or may not be physical units, that is, the units may be located in one place, or may be distributed over multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions in the embodiments.

In addition, the functional units in the embodiments of the present disclosure may be integrated in one processing unit, or the units may exist alone physically, or two or more units may be integrated in one unit.

The functions may also be stored in a computer-readable storage medium if being implemented in the form of a software functional unit and sold or used as an independent product. Based on such understanding, the essence of the technical solutions of the present disclosure, or the part contributing to the prior art or part of the technical solutions, may be embodied in the form of a software product. The computer software product is stored in a storage medium including a number of instructions such that a computer device (which may be a personal computer, a server, or a network device, etc. ) performs all or part of steps of the method described in each of the embodiments of the present disclosure. The foregoing storage medium includes: any medium that is capable of storing program codes such as a USB disk, a mobile hard disk, a Read-Only Memory (ROM) , a Random Access Memory (RAM) , a magnetic disk or an optical disk, and the like.

The foregoing descriptions are merely exemplary embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope of the present disclosure, and all the changes or substitutions should be covered by the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be defied by the appended claims.

Claims

A sidelink communication method, comprising:

generating, by a first terminal device, a sidelink control channel and data according to a sub-slot length; and

transmitting, by the first terminal device, the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to a second terminal device, wherein the plurality of sub-slots comprises the first sub-slot.
The method according to claim 1, wherein a starting position of the first sub-slot is the second symbol in the slot.
The method according to claim 1 or 2, wherein an ending position of a last sub-slot in the slot is associated with at least Physical Sidelink Feedback Channel (PSFCH) resources allocation.
The method according to any one of claims 1 to 3, wherein the sidelink control channel is further transmitted in other sub-slots than the first sub-slot in the slot.
The method according to any one of claims 1 to 4, wherein transmitting the data in the plurality of sub-slots within the slot, comprises:

performing an initial transmission of the data to the second terminal in the first sub-slot; and

performing at least one retransmission of the data in at least one remaining sub-slots other than the first sub-slot in the slot, wherein each of the at least one retransmission of the data is associated with a different redundancy version which is comprised in a corresponding second stage Sidelink Control Information (SCI) .
The method according to any one of claims 1 to 5, wherein generating of the sidelink control channel comprises:

encoding first stage Sidelink Control Information (SCI) into the sidelink control channel, wherein the first stage SCI comprises indication information which is used to indicate whether sub-slot sidelink transmission is applied and/or the sub-slot length.
The method according to claim 6, wherein the indication information comprises at least one bit to indicate the sub-slot length, or an index corresponding to the sub-slot length.
The method according to any one of claims 1 to 7, further comprising:

obtaining information regarding one or more sub-slot lengths that can be used by the first terminal for sub-slot sidelink transmission;

wherein generating of the sidelink control channel and the data according to the sub-slot length comprises:

selecting, by the first terminal device, a sub-slot length from the one or more sub-slot lengths according to at least one of a packet latency requirement, a data packet size and number of retransmissions per MAC PDU or TB; and

generating the sidelink control channel and the data according to the selected sub-slot length.
The method according to any one of claims 1 to 8, wherein transmitting of the sidelink control channel and the data to the second terminal device comprises:

transmitting, by the first terminal device, the sidelink control channel in a first frequency domain resource, and transmitting a sidelink data channel carrying the data in a second frequency domain resource that is separated from the first frequency domain resource in a frequency domain.
The method according to claim 9, wherein a power for transmitting the sidelink control channel is different from a power for transmitting the sidelink data channel.
The method according to any one of claims 1 to 9, further comprising:

obtaining, by the first terminal device, configuration of whether physical sidelink control channel is to be transmitted in the first sub-slot or all sub-slots in the slot.
The method according to claim 11, wherein whether sidelink control channel is to be transmitted in the first sub-slot or all sub-slots in the slot is pre-configured.
The method according to any one of claims 1 to 12, wherein transmitting, by the first terminal device, the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to a second terminal device comprises:

selecting resources from a sub-set of resources within a resource pool, wherein the sub-set of resources are configured or pre-configured as allowing sub-slot transmission; and

transmitting, by the first terminal device, the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to the second terminal device using the selected resources.
A sidelink communication method, comprising:

receiving, by a second terminal device, a sidelink control channel in at least a first sub-slot within a slot and data in a plurality of sub-slots within the slot from a first terminal device, wherein the plurality of sub-slots comprises the first sub-slot, and the sidelink control channel and data is generated according to a sub-slot length; and

decoding, by the second terminal device, the data according to the sidelink control channel.
The method according to claim 14, wherein a starting position of the first sub-slot is the second symbol in the slot.
The method according to claim 14 or 15, wherein an ending position of a last sub-slot in the slot is associated with at least Physical Sidelink Feedback Channel (PSFCH) resources allocation.
The method according to any one of claims 14 to 16, wherein the sidelink control channel is further received in other sub-slots than the first sub-slot in the slot.
The method according to claim 17, further comprising:

performing, by the second terminal device, channel combing on the sidelink control channel which is received in all sub-slots in the slot.
The method according to any one of claims 14 to 18, wherein receiving of the data in the plurality of sub-slots within the slot, comprises:

receiving, by the second terminal device, the data as an initial transmission in the first sub-slot; and

receiving, by the second terminal device, the data as at least one retransmission in at least one remaining sub-slots other than the first sub-slot in the slot, wherein each of the at least one retransmission of the data is associated with a different redundancy version which is comprised in a corresponding second stage Sidelink Control Information (SCI) .
The method according to any one of claims 14 to 19, wherein the sidelink control channel comprises first stage Sidelink Control Information (SCI) , and the first stage SCI comprises indication information which is used to indicate whether sub-slot sidelink transmission is applied and/or the sub-slot length;

wherein the method further comprises:

determining, by the second terminal device, a position and a length of a data channel carrying the data according to the indication;

wherein decoding of the data further comprises:

decoding the data channel to obtain the data according to the position and length of the data channel.
The method according to claim 20, wherein the indication information comprises at least one bit to indicate the sub-slot length, or an index corresponding to the sub-slot length.
The method according to any one of claims 14 to 21, wherein receiving of the sidelink control channel and data comprises:

receiving, by the second terminal device, the sidelink control channel in a frequency domain resource, and receiving a sidelink data channel carrying the data in a second frequency domain resource that is separated from the first frequency domain resource in a frequency domain.
The method according to claim 22, wherein a power for transmitting the sidelink control channel is different from a power for transmitting the sidelink data channel.
A first terminal device, comprising:

a generation module configured to generate a sidelink control channel and data according to a sub-slot length; and

a transmitting module configured to transmit the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to a second terminal device, wherein the plurality of sub-slots comprises the first sub-slot.
The terminal device according to claim 24, wherein a starting position of the first sub-slot is the second symbol in the slot.
The terminal device according to claim 24 or 25, wherein an ending position of a last sub-slot in the slot is associated with at least Physical Sidelink Feedback Channel (PSFCH) resources allocation.
The terminal device according to any one of claims 24 to 26, wherein the sidelink control channel is further transmitted in other sub-slots than the first sub-slot in the slot.
The terminal device according to any one of claims 24 to 27, wherein the transmitting module is configured to:

perform an initial transmission of the data to the second terminal in the first sub-slot; and

perform at least one retransmission of the data in at least one remaining sub-slots other than the first sub-slot in the slot, wherein each of the at least one retransmission of the data is associated with a different redundancy version which is comprised in a corresponding second stage Sidelink Control Information (SCI) .
The terminal device according to any one of claims 24 to 28, wherein the generation module is configured to:

encode first stage Sidelink Control Information (SCI) into the sidelink control channel, wherein the first stage SCI comprises indication information which is used to indicate whether sub-slot sidelink transmission is applied and/or the sub-slot length.
The terminal device according to claim 29, wherein the indication information comprises at least one bit to indicate the sub-slot length, or an index corresponding to the sub-slot length.
The terminal device according to any one of claims 24 to 30, further comprising:

an obtaining module configured to obtain information regarding one or more sub-slot lengths that can be used by the first terminal for sub-slot sidelink transmission;

wherein the generating module is configured to:

select a sub-slot length from the one or more sub-slot lengths according to at least one of a packet latency requirement, a data packet size and number of retransmissions per MAC PDU or TB; and

generate the sidelink control channel and the data according to the selected sub-slot length.
The terminal device according to any one of claims 24 to 31, wherein the transmitting module is configured to:

transmit the sidelink control channel in a first frequency domain resource, and transmit a sidelink data channel carrying the data in a second domain frequency that is separated from the first frequency domain resource in a frequency domain.
The terminal device according to claim 32, wherein a power for transmitting the sidelink control channel is different from a power for transmitting the sidelink data channel in the sub-slots is incrementally increased.
The terminal device according to any one of claims 24 to 33, further comprising:

an obtaining module configured to obtain configuration of whether physical sidelink control channel is to be transmitted in the first sub-slot or all sub-slots in the slot.
The terminal device according to claim 34, wherein whether sidelink control channel is to be transmitted in the first sub-slot or all sub-slots in the slot is pre-configured.
The terminal device according to any one of claims 24 to 35, wherein the transmission module is configured to:

select resources from a sub-set of resources within a resource pool, wherein the sub-set of resources are configured or pre-configured as allowing sub-slot transmission; and

transmit the sidelink control channel in at least a first sub-slot within a slot and the data in a plurality of sub-slots within the slot to the second terminal device using the selected resources.
A second terminal device, comprising:

a receiving module configured to receive a sidelink control channel in at least a first sub-slot within a slot and data in a plurality of sub-slots within the slot from a first terminal device, wherein the plurality of sub-slots comprises the first sub-slot, and the sidelink control channel and data is generated according to a sub-slot length; and

a decoding module configured to decode the data according to the sidelink control channel.
The terminal device according to claim 37, wherein a starting position of the first sub-slot is the second symbol in the slot.
The terminal device according to claim 36 or 37, wherein an ending position of a last sub-slot in the slot is associated with at least Physical Sidelink Feedback Channel (PSFCH) resources allocation.
The terminal device according to any one of claims 37 to 39, wherein the sidelink control channel is further received in other sub-slots than the first sub-slot in the slot.
The terminal device according to claim 40, further comprising:

a channel combination module configured to perform channel combing on the sidelink control channel which is received in all sub-slots in the slot.
The terminal device according to any one of claims 37 to 41, wherein the receiving module is configured to:

receive the data as an initial transmission in the first sub-slot; and

receive the data as at least one retransmission in at least one remaining sub-slots other than the first sub-slot in the slot, wherein each of the at least one retransmission of the data is associated with a different redundancy version which is comprised in a corresponding second stage Sidelink Control Information (SCI) .
The terminal device according to any one of claims 37 to 42, wherein the sidelink control channel comprises first stage Sidelink Control Information (SCI) , and the first stage SCI comprises indication information which is used to indicate whether sub-slot sidelink transmission is applied and/or the sub-slot length;

wherein the device further comprises:

a determination module configured to determine a position and a length of a data channel carrying the data according to the indication;

wherein the decoding module is further configured to:

decode the data channel to obtain the data according to the position and length of the data channel.
The terminal device according to claim 43, wherein the indication information comprises at least one bit to indicate the sub-slot length, or an index corresponding to the sub-slot length.
The terminal device according to any one of claims 37 to 44, wherein the receiving module is configured to:

receive the sidelink control channel in a first frequency domain resource, and receiving a sidelink data channel carrying the data in a second frequency domain resource that is separated from the first frequency domain resource in a frequency domain.
The terminal device according to claim 45, wherein a power for transmitting the sidelink control channel is different from a power for transmitting the sidelink data channel.
A terminal device, comprising a processor and a memory configured to store a computer program, wherein the processor is used to call and run the computer program stored in the memory to perform the method according to any one of claims 1 to 13.
A terminal device, comprising a processor and a memory configured to store a computer program, wherein the processor is used to call and run the computer program stored in the memory to perform the method according to any one of claims 14 to 23.
A chip, comprising: a processor configured to call and run a computer program stored in a memory to cause a device in which the chip is installed to perform the method according to any one of claims 1 to 13.
A chip, comprising: a processor configured to call and run a computer program stored in a memory to cause a device in which the chip is installed to perform the method according to any one of claims 14 to 23.
A computer-readable storage medium configured to store a computer program, wherein the computer program is configured to cause a computer to perform the method according to any one of claims 1 to 13.
A computer-readable storage medium configured to store a computer program, wherein the computer program is configured to cause a computer to perform the method according to any one of claims 14 to 23.
A computer program product comprising computer program instructions that cause a computer to perform the method according to any one of claims 1 to 13.
A computer program product comprising computer program instructions that cause a computer to perform the method according to any one of claims 14 to 23.
A computer program configured to cause a computer to perform the method according to any one of claims 1 to 13.
A computer program configured to cause a computer to perform the method according to any one of claims 14 to 23.