WO2025065194A1

WO2025065194A1 - Devices and methods for sidelink communication

Info

Publication number: WO2025065194A1
Application number: PCT/CN2023/121273
Authority: WO
Inventors: Boyuan ZHANG; Zhaobang MIAO; Jin Yang; Gang Wang
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2023-09-25
Filing date: 2023-09-25
Publication date: 2025-04-03
Anticipated expiration: 2026-03-25

Abstract

Embodiments of the present disclosure provide a solution for sidelink communication. In a solution, a first terminal device receives, from a first device, first information about resources for the first terminal device to perform sidelink communication; and transmits, to a second device, second information associated with the first information, and wherein one of the first and second devices comprises a second terminal device sharing a channel occupation time (COT) with the first terminal device, and the other one of the first and second devices comprises a network device.

Description

DEVICES AND METHODS FOR SIDELINK COMMUNICATION

FIELDS

Example embodiments of the present disclosure generally relate to the field of communication techniques and in particular, to devices and methods for sidelink (SL) communication.

BACKGROUND

With the development of communication techniques, a variety of communication networks have been developed or studied. In some wireless communication networks, in addition to communicating with base stations via access links, user equipment (UE) can communicate with other devices using a sidelink (e.g., a communication link between a UE and another UE) as well. Such communication may relate to, for example, vehicle-based communication devices that can communicate from vehicle-to-vehicle (V2V) , vehicle-to-infrastructure (V2I) (e.g., from the vehicle-based communication device to road infrastructure nodes) , vehicle-to-network (V2N) (e.g., from the vehicle-based communication device to one or more network nodes, such as a base station) , a combination thereof and/or with other devices, which can be collectively referred to as vehicle-to-anything (V2X) communications. Further improvements related to the sidelink communication are desired.

SUMMARY

In a first aspect, there is provided a first terminal device comprising: a processor configured to cause the first terminal device to: receive, from a first device, first information about resources for the first terminal device to perform sidelink communication; and transmit, to a second device, second information associated with the first information, and wherein one of the first and second devices comprises a second terminal device sharing a channel occupation time (COT) with the first terminal device, and the other one of the first and second devices comprises a network device.

In a second aspect, there is provided a second terminal device comprising: a processor configured to cause the second terminal device to: receive, from a first terminal device, assistant information for channel occupation time (COT) sharing with the first terminal device, and wherein the assistant information is associated with a configuration of a resource pool for using by the first terminal device.

In a third aspect, there is provided a network device comprising: a processor configured to cause the network device to: receive, from a first terminal device, a report associated with at least a channel occupation time (COT) sharing indication from a second terminal device.

In a fourth aspect, there is provided a terminal device comprising: a processor configured to cause the terminal device to: receive, from a network device, a configuration indicating a plurality of carrier frequencies for sidelink communication of the terminal device, wherein the terminal device is capable of carrier aggregation; and in accordance with a determination that a first condition is met, select a single carrier frequency for the sidelink communication, wherein the first condition is associated with a first logical channel selected by the terminal device or an activation status of the carrier aggregation for the terminal device.

In a fifth aspect, there is provided a first terminal device comprising: a processor configured to cause the first terminal device to: receive, from a second terminal device, a channel occupation time (COT) sharing indication; and in accordance with a determination that a sidelink grant is within a COT indicated in the COT sharing indication, select a destination for logical channel prioritization associated with the sidelink grant based on a communication type and an identity indicated in the COT sharing indication.

In a sixth aspect, there is provided a second terminal device comprising: a processor configured to cause the second terminal device to: transmit, to a first terminal device, a channel occupation time (COT) sharing indication; and receive, from the first terminal device, at least one of: one or more destination identities maintained by the first terminal device for groupcast or broadcast, or a pair of a source identity and a destination identity for unicast.

In a seventh aspect, there is provided a terminal device comprising: a processor configured to cause the terminal device to: obtain a transmission profile associated with a destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and in accordance with an absence of a sidelink configuration for the indicated compatibility, transmit, to a network device, sidelink information to request the sidelink configuration, the siedlink information comprising the destination identity and the transmission profile.

In an eighth aspect, there is provided a network device comprising: a processor configured to cause the terminal device to: receive, from a terminal device, sidelink information comprising a destination identity and a transmission profile asscioated with the destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and determine, based on the sidelink information, that the terminal device requests a sidelink configuration for the indicated compatibility.

In a ninth aspect, there is provided a communication method performed by a first terminal device. The method comprises: receiving, from a first device, first information about resources for the first terminal device to perform sidelink communication; and transmitting, to a second device, second information associated with the first information, and wherein one of the first and second devices comprises a second terminal device sharing a channel occupation time (COT) with the first terminal device, and the other one of the first and second devices comprises a network device.

In a tenth aspect, there is provided a communication method performed by a second terminal device. The method comprises: receiving, from a first terminal device, assistant information for channel occupation time (COT) sharing with the first terminal device, and wherein the assistant information is associated with a configuration of a resource pool for using by the first terminal device.

In an eleventh aspect, there is provided a communication method performed by a network device. The method comprises: receiving, from a first terminal device, a report associated with at least a channel occupation time (COT) sharing indication from a second terminal device.

In a twelfth aspect, there is provided a communication method performed by a terminal device. The method comprises: receiving, from a network device, a configuration indicating a plurality of carrier frequencies for sidelink communication of the terminal device, wherein the terminal device is capable of carrier aggregation; and in accordance with a determination that a first condition is met, selecting a single carrier frequency for the sidelink communication, wherein the first condition is associated with a first logical channel selected by the terminal device or an activation status of the carrier aggregation for the terminal device.

In a thirteenth aspect, there is provided a communication method performed by a first terminal device. The method comprises: receiving, from a second terminal device, a channel occupation time (COT) sharing indication; and in accordance with a determination that a sidelink grant is within a COT indicated in the COT sharing indication, selecting a destination for logical channel prioritization associated with the sidelink grant based on a communication type and an identity indicated in the COT sharing indication.

In a fourteenth aspect, there is provided a communication method performed by a second terminal device. The method comprises: transmitting, to a first terminal device, a channel occupation time (COT) sharing indication; and receiving, from the first terminal device, at least one of: one or more destination identities maintained by the first terminal device for groupcast or broadcast, or a pair of a source identity and a destination identity for unicast.

In a fifteenth aspect, there is provided a communication method performed by a terminal device. The method comprises: obtaining a transmission profile associated with a destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and in accordance with an absence of a sidelink configuration for the indicated compatibility, transmitting, to a network device, sidelink information to request the sidelink configuration, the siedlink information comprising the destination identity and the transmission profile.

In a sixteenth aspect, there is provided a communication method performed by a network device. The method comprises: receiving, from a terminal device, sidelink information comprising a destination identity and a transmission profile asscioated with the destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and determining, based on the sidelink information, that the terminal device requests a sidelink configuration for the indicated compatibility.

In a seventeenth aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to the ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, or sixteenth aspect.

Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some example embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

FIG. 1 illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;

FIG. 2 illustrates a schematic diagram of resources scheduled by a network device and resource block sets indicated by COT sharing information in a resource pool;

FIG. 3A illustrates a signaling flow of reporting channel occupation time (COT) sharing in accordance with some embodiments of the present disclosure;

FIG. 3B illustrates a signaling flow of transmitting COT sharing assistant information in accordance with some embodiments of the present disclosure;

FIG. 4 illustrates a signaling flow of carrier selection in accordance with some embodiments of the present disclosure;

FIG. 5 illustrates a signaling flow of destination determination for an logical channel prioritization (LCP) procedure in accordance with some embodiments of the present disclosure;

FIG. 6 illustrates a signaling flow of configuration for backward compatibility in accordance with some embodiments of the present disclosure;

FIG. 7 illustrates a signaling flow of a frequency configuration in accordance with some embodiments of the present disclosure;

FIG. 8 illustrates a flowchart of a method implemented at a first terminal device according to some example embodiments of the present disclosure;

FIG. 9 illustrates a flowchart of a method implemented at a second terminal device according to some example embodiments of the present disclosure;

FIG. 10 illustrates a flowchart of a method implemented at a network device according to some example embodiments of the present disclosure;

FIG. 11 illustrates a flowchart of a method implemented at a terminal device according to some example embodiments of the present disclosure;

FIG. 12 illustrates a flowchart of a method implemented at a first terminal device according to some example embodiments of the present disclosure;

FIG. 13 illustrates a flowchart of a method implemented at a second terminal device according to some example embodiments of the present disclosure;

FIG. 14 illustrates a flowchart of a method implemented at a terminal device according to some example embodiments of the present disclosure;

FIG. 15 illustrates a flowchart of a method implemented at a network device according to some example embodiments of the present disclosure;

FIG. 16 illustrates a simplified block diagram of an apparatus that is suitable for implementing example embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

As used herein, the term ‘terminal device’ refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Ultra-reliable and Low Latency Communications (URLLC) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, devices on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, devices for Integrated Access and Backhaul (IAB) , Space borne vehicles or Air borne vehicles in Non-terrestrial networks (NTN) including Satellites and High Altitude Platforms (HAPs) encompassing Unmanned Aircraft Systems (UAS) , eXtended Reality (XR) devices including different types of realities such as Augmented Reality (AR) , Mixed Reality (MR) and Virtual Reality (VR) , the unmanned aerial vehicle (UAV) commonly known as a drone which is an aircraft without any human pilot, devices on high speed train (HST) , or image capture devices such as digital cameras, sensors, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. The ‘terminal device’ can further has ‘multicast/broadcast’ feature, to support public safety and mission critical, V2X applications, transparent IPv4/IPv6 multicast delivery, IPTV, smart TV, radio services, software delivery over wireless, group communications and IoT applications. It may also incorporate one or multiple Subscriber Identity Module (SIM) as known as Multi-SIM. The term “terminal device” can be used interchangeably with a UE, a mobile station, a subscriber station, a mobile terminal, a user terminal or a wireless device.

The term “network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a next generation NodeB (gNB) , a transmission reception point (TRP) , a remote radio unit (RRU) , a radio head (RH) , a remote radio head (RRH) , an IAB node, a low power node such as a femto node, a pico node, a reconfigurable intelligent surface (RIS) , and the like.

The terminal device or the network device may have Artificial intelligence (AI) or Machine learning capability. It generally includes a model which has been trained from numerous collected data for a specific function, and can be used to predict some information.

The terminal or the network device may work on several frequency ranges, e.g., FR1 (e.g., 450 MHz to 6000 MHz) , FR2 (e.g., 24.25GHz to 52.6GHz) , frequency band larger than 100 GHz as well as Tera Hertz (THz) . It can further work on licensed/unlicensed/shared spectrum. The terminal device may have more than one connection with the network devices under Multi-Radio Dual Connectivity (MR-DC) application scenario. The terminal device or the network device can work on full duplex, flexible duplex and cross division duplex modes.

The embodiments of the present disclosure may be performed in test equipment, e.g., signal generator, signal analyzer, spectrum analyzer, network analyzer, test terminal device, test network device, channel emulator. In some embodiments, the terminal device may be connected with a first network device and a second network device. One of the first network device and the second network device may be a master node and the other one may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In some embodiments, the first network device may be a first RAT device and the second network device may be a second RAT device. In some embodiments, the first RAT device is eNB and the second RAT device is gNB. Information related with different RATs may be transmitted to the terminal device from at least one of the first network device or the second network device. In some embodiments, first information may be transmitted to the terminal device from the first network device and second information may be transmitted to the terminal device from the second network device directly or via the first network device. In some embodiments, information related with configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related with reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

As used herein, the singular forms ‘a’ , ‘an’ and ‘the’ are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term ‘includes’ and its variants are to be read as open terms that mean ‘includes, but is not limited to. ’ The term ‘based on’ is to be read as ‘at least in part based on. ’ The term ‘one embodiment’ and ‘an embodiment’ are to be read as ‘at least one embodiment. ’ The term ‘another embodiment’ is to be read as ‘at least one other embodiment. ’ The terms ‘first, ’ ‘second, ’ and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

In some examples, values, procedures, or apparatus are referred to as ‘best, ’ ‘lowest, ’ ‘highest, ’ ‘minimum, ’ ‘maximum, ’ or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

As used herein, the term “resource, ” “transmission resource, ” “uplink resource, ” or “downlink resource” may refer to any resource for performing a communication, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other resource enabling a communication, and the like. In the following, unless explicitly stated, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that example embodiments of the present disclosure are equally applicable to other resources in other domains.

As used herein, a resource block (RB) set in a resource pool may comprise a certain number of resource blocks. RB sets with different numbers of RBs may be defined for different resource pools. An RB set may also be referred to as a frequency unit, a frequency band, or a sub-band, or a channel. In some cases, there may be a gap of guard band between two contiguous RB sets in a resource pool.

As used herein, the term “backward compatible” or the like refers to being compatible with non-carrier aggregation. Similarly, the term “backward incompatible” or the like refers to being incompatible with non-carrier aggregation.

Principles and implementations of the present disclosure will be described in detail below with reference to the figures.

Example environment

FIG. 1 illustrates a schematic diagram of an example communication environment 100 in which example embodiments of the present disclosure can be implemented. In the communication environment 100, a plurality of communication devices, including a network device 130, a first terminal device 110, and a second terminal device 120 can communicate with each other.

In the example of FIG. 1, the first terminal device 110 and the second terminal device 120 may be UEs. The network device 130 may be a base station serving the UEs, for example, a gNB.

It is to be understood that the number of devices and their connections shown in FIG. 1 are only for the purpose of illustration without suggesting any limitation. The communication environment 100 may include any suitable number of devices configured to implementing example embodiments of the present disclosure.

In the following, for the purpose of illustration, some example embodiments are described with the first terminal device 110 and the second terminal device 120 operating as UEs and the network device 120 operating as a base station. However, in some example embodiments, operations described in connection with a terminal device may be implemented at a network device or other device, and operations described in connection with a network device may be implemented at a terminal device or other device.

The communications in the communication environment 100 may conform to any suitable standards including, but not limited to, Global System for Mobile Communications (GSM) , Long Term Evolution (LTE) , LTE-Evolution, LTE-Advanced (LTE-A) , New Radio (NR) , Wideband Code Division Multiple Access (WCDMA) , Code Division Multiple Access (CDMA) , GSM EDGE Radio Access Network (GERAN) , Machine Type Communication (MTC) and the like. The embodiments of the present disclosure may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, 5.5G, 5G-Advanced networks, or the sixth generation (6G) networks.

In some example embodiments, the network device 130 may communicate with the first terminal device 110 and/or the second terminal device 120. A link from the network device 130 to the first terminal device 110 and/or the second terminal device 120 is referred to as a downlink (DL) , while a link from the first terminal device 110 and/or the second terminal device 120 to the network device 120 is referred to as an uplink (UL) . In DL, the network device 130 is a transmitting (TX) device (or a transmitter) and the first terminal device 110 and/or the second terminal device 120 is a receiving (RX) device (or a receiver) . In UL, the first terminal device 110 and/or the second terminal device 120 is a TX device (or a transmitter) and the network device 130 is a RX device (or a receiver) .

The first terminal device 110 and the second terminal device 120 can communicate with each other over a sidelink. The communication between the first terminal device 110 and the second terminal device 120 over the sidelink may be referred to as sidelink communication or sidelink transmission. There may be different modes for allocating the resource for the sidelink communication, which are referred to as resource allocation (RA) modes.

The RA modes may include a first mode and a second mode which are different from each other in SL resource allocation. In some example embodiments, the first mode may be the mode 1, which is also referred to as a network scheduled resource allocation scheme. In mode 1, the resource for the sidelink communication is scheduled by the network device 130. For example, in mode 1, the network device 130 may configure the first terminal device 110 and/or the second terminal device 120 with a resource pool for sidelink data transmission and/or sidelink control information transmission.

As an example but without any limitation, in mode 1, the network device 130 may schedule the first terminal device 110 and/or the second terminal device 120 to perform SL transmission, and there may be a dedicated resource pool for resource scheme in mode 1. The network device 130 may perform resource allocation for physical sidelink control channel (PSCCH) and/or physical sidelink shared channel (PSSCH) , and dynamic scheduling and configured grant (which is semi-persistent scheduling (SPS) and shorted as CG) may be supported. There are two types of CG which are type 1 CG and type 2 CG. Dynamic scheduling is based on downlink control information (DCI) . Type 1 CG is based on radio resource control (RRC) configuration. Type 2 CG is based on RRC configuration and activated by DCI. Scheduling more than one resources for a TB for initial transmission and retransmission (s) is supported. The network device 130 does not receive SL signals.

The first terminal device 110 and/or the second terminal device 120 in SL communication may transmit sidelink control information (SCI) /data on the scheduled PSCCH/PSSCH resources. The RRC connection (for example, a Uu connection) is made between the terminal device and the network device 130. Dedicated radio network temporary identification (RNTI) for SL scheduling DCI is different from Uu RNTI. SL Acknowledge (ACK) /Negative Acknowledge (NACK) may be forwarded to the network device 130 on physical uplink control channel (PUCCH) and/or physical uplink shared channel (PUSCH) according to configuration.

The second mode may be mode 2, which may be also referred to as an autonomously resource selection scheme. In mode 2, the resource for the sidelink communication is selected by the first terminal device 110 and/or the second terminal device 120.

As an example but without any limitation, in mode 2, the first terminal device 110 and/or the second terminal device 120 may select SL resources to perform SL transmission. Mode 2 may include a full sensing scheme, a partial sensing scheme, and a random selection scheme. In the full sensing scheme, initial candidate resources are firstly set as a full set, and then unavailable resources are excluded from the candidate resource set. At last, the final candidate resource set is determined. In some embodiments, inter-UE coordination (IUC) may be used when IUC is (pre-) configured and triggered. If the IUC is triggered, the preferred resource set may be determined for other terminal device’s transmission or the non-preferred resource set from other terminal device (s) may be excluded.

Some mechanism regarding the mode 1 and mode 2 are described. It is to be understood that the mode 1 and mode 2 are given as examples without any limitation, and other RA modes are possible.

In some embodiments, carrier aggregation (CA) may be adopted for the sidelink communication. At least one of the first terminal device 110 and the second terminal device 120 may be capable of CA.

In some embodiments, the first terminal device 110 and the second terminal device 120 may perform channel occupation time (COT) sharing. The terminal device which shares the COT with a peer terminal device may be referred to as an initiating terminal device (e.g., an initiating UE) and the peer terminal device which receives the COT sharing information may be referred to as a responding terminal device (e.g., a responding UE) . Then, the initiating terminal device and the responding terminal device may perform sidelink transmission using the shared COT. For example, the responding terminal device may perform unicast transmission to the initiating terminal device using the shared COT. Alternatively, the responding terminal device may perform groupcast or broadcast transmission to a plurality of terminal devices including the initiating terminal device.

To better understand the embodiments of the present disclosure, some solutions for sidelink (SL) communication are now described. For NR sidelink CA operation, there are some solutions on TX profile extension for SL CA. When the upper layer provides multiple carriers in service to carrier mapping information to Access Stratum (AS) , TX profile extension is needed to inform whether the transmission corresponding the service is backward compatible or not. If backward compatibility is needed, only a legacy carrier is used for transmission when Packet Data Convergence Protocol (PDCP) duplication is not used. If the PDCP duplication is used, at least a legacy carrier is used. Whether to use PDCP duplication or not is up to UE implementation.

In some solutions, SL CA may not be applied before UC link is established. It may be assumed that the AS layer may maintain a mapping between an old layer 2 (L2) ID (before PC5 link establishment) and a new L2 ID (after PC5 link establishment) by its implementation.

For per-carrier CBR, a same principle as LTE V2X CA may be applied to determine per-carrier CBR.

For NR sidelink operation in the FR1 unlicensed spectrum, there are some solutions on consistent listen before talk (C-LBT) failure. For SL C-LBT failure recovery (for example in RRC connected mode 2) , the C-LBT failure recovery for RRC idle/inactive mode 2 may be applied. C-LBT failure cancellation conditions may include upon MAC reset, upon C-LBT count and/or timer reconfiguration, and/or based on a timer expiry. The timer may start upon the C-LBT failure.

For C-LBT failure with Physical Sidelink Feedback Channel (PSFCH) , LBT failure indications may be counted regardless of whether LBT failure was provided because of PSFCH transmission or not when RB set for PSFCH transmission belongs to the selected TX resource pool. The scenario when multiple PSFCH occasions are configured is for further studied. LBT failure indication may be provided from L1 once each transmission fails per PSFCH occasion in multiple PSFCH occasions.

There are some solutions on NR sidelink operation on FR1 unlisenced spectrum. For SL C-LBT failure media access control (MAC) control element (CE) , 5 bits indication may be used per SL carrier and how the RB set index is derived, whether the RB set index is unique within SL-BWP need further studies. LCP order of SL LBT failure MAC CE is defined as the next of Uu LBT Failure MAC CE. Dedicated SR configuration can be configured.

SL C-LBT failure detection and recovery counter and timer may be configured per SL BWP and maintained per RB set. For a SL radio link failure (RLF) report as the result of C-LBT failures, no new code-point or a cause value may be needed.

For enhanced LCP for shared COT, enhanced LCP may be used if the shared COT is used with LBT type 2 for mode 2. In other cases, enhanced LCP may not be used. No change compared to enhanced LCP in mode 2 is needed for the case when the COT responding UE receives mode 1 resource and shared COT from a COT initiating UE.

For resource (re) selection with consideration of intra-UE LBT impact, UE may avoid selection of N consecutive resource (s) before a reserved resource of its own. Where the selection of N is up to UE implementation from {0, 1, 2} . The UE may avoid selection of M consecutive resource (s) after a reserved resource of its own. The selection of M is up to an implementation (at least including 0) of the UE.

For multiple shared COTs, it is up to the implementation of the UE to use which one out of multiple ones when receiving multiple COT sharing indications from different COT initiators.

Regarding the COT sharing indication, an “Additional ID (s) ” field may be supported for unicast, groupcast and broadcast, and it is carried in the second stage sildelink control information (SCI) , which may comprise one pair of L1 source and destination IDs of 24 bits for all cast types plus 2 bits for the cast type. At least for unicast, the source ID is set to the source ID of the COT initiator corresponding to the intended destination.

Regarding C-LBT failure handling and/or recovery, the additional ID may include one pair of L1 source and destination IDs of 24 bits for all cast types. For groupcast and broadcast, only L1 destination ID is provided, and source ID bits are reserved. A Uu MAC CE indicates RB set (s) where the C-LBT failure happens.

Synchronization mechanism for COT

For the COT sharing mechanism, for example, for mode 1 responding UE, when the responding UE receiving one COT from other initiating UE, gNB has no knowledge about the COT sharing information. As a result, the gNB would keep scheduling on the original SL resources, of which the resources might not fall into the COT. Therefore, the COT would be useless with a high possibility (from time domain and frequency domain) .

FIG. 2 shows a schematic diagram of resources scheduled by the network and resource block sets indicated by COT sharing information in a resource pool. As shown, resources 210 scheduled by the network and RB sets 220 indicated by the COT sharing information occupy different resource blocks. In this case, how to synchronize the COT sharing information between the initiating terminal device and the network device is needed.

To this end, a synchronization scheme is proposed. In this scheme, the network device may obtain the knowledge of COT sharing information so that it can schedule mode 1 resources accordingly. Alternatively, or in addition, the initiating terminal device may have the knowledge of resource allocation information so that it can share COT information accordingly.

In some embodiments, the first terminal device which may be a responding terminal device receives, from a first device, first information about resources for the first terminal device to perform sidelink communications. Then, the first terminal device may transmit, to a second device, second information associated with the first information. One of the first and second devices may be a second terminal device sharing a COT with the first terminal device, and the other one of the first and second devices may be a network device.

In some embodiments, the first device may be the second terminal device, and the second device may be the network device. Accordingly, the first information may comprise a COT sharing indication, and the second information may comprise a report associated with the COT sharing indication. In other words, in such embodiments, the responding terminal device may report the COT sharing to the network device.

Reference is now made to FIG. 3A to describe an example flow of such embodiments. FIG. 3A illustrate an example signaling flow 300A of COT sharing in accordance with some embodiments of the present disclosure. For the purposes of discussion, the signaling flow 300A will be discussed with reference to FIG. 1, for example, by using the first terminal device 110, the second terminal device 120, and the network device 130.

As shown in FIG. 3A, in some example embodiments, the second terminal device 120 may transmit (315) a COT sharing indication to the first terminal device 110. Correspondingly, the first terminal device 110 may receive (320) the COT sharing indication from the second terminal device 120. In other words, the second terminal device 120 may share COT with the first terminal device 110. The COT sharing indication may be also referred to as COT sharing information. In some embodiments, the first terminal device 110 may be referred to as the responding UE and the second terminal device 120 may be referred to as the initiating UE. However, this is for purpose of discussion without any limitation.

Then, in some example embodiments, the first terminal device 110 may determine (325) whether at least one condition is met. If the at least one condition is met, the first terminal device 110 may report the COT sharing information to the network device 130. Specifically, as shown in FIG. 3A, the first terminal device 110 may transmit (330) to the network device 130, the report associated with the COT sharing indication. Accordingly, the network device 130 may receive (335) , from the first terminal device 110, the report associated with at least a COT sharing indication from the second terminal device 120.

The report may be transmitted in any suitable signaling. In an example, the first terminal device 110 may transmit the report to the second device through a UL MAC CE or an RRC message.

The condition may comprise that the first terminal device 110 is to use a resource indicated in the COT sharing indication. For example, the responding UE decides to use the COT shared by the initiating UE.

Alternatively, or in addition, the condition may comprise that the first terminal device 110 is in a connected state with the network device 130. For example, the responding UE is in an RRC_CONNECTED state.

Alternatively, or in addition, the condition may comprise that a resource block set indicated in the COT sharing indication is not comprised in a resource block set of a resource pool used by the first terminal device 110. For example, the shared COT does not belong to the resource block set of the resource pool configuration currently used by the responding UE.

Alternatively, or in addition, the condition may comprise that the first terminal device 110 is operating in a predetermined resource allocation mode. For example, the responding UE may be operating in the resource allocation mode 1 or mode 2.

Alternatively, or in addition, the condition may comprise that a consistent listen before talk (LBT) failure is detected on a resource block set of the resource pool used by the first terminal device 110. For example, the consistent LBT failure may happen on an RB set of the resource pool currently used by the responding UE.

In some example embodiments, a timer may be configured. Accordingly, the first terminal device 110 may start a timer upon detection of the consistent LBT failure and transmit the report to the network device 130 in response to expiration of the timer. For example, once the consistent LBT failure is happened, the responding UE may start the timer. Within duration of the timer, the responding UE may decide whether to report the COT sharing information according to the condition. If the responding UE has not decided whether to report, and the timer is expired, the responding UE may not report the COT sharing information based on the condition.

The report may include any suitable information about the COT sharing. In some example embodiments, the report may comprise the device identification of the second terminal device 120, for example, a UE ID of the initiating UE.

Alternatively, or in addition, the report may comprise an index of a resource block set indicated in the COT sharing indication. Alternatively, or in addition, the report may comprise an index of a slot indicated in the COT sharing indication. For example, the report may include the RB set index and the slot index of the COT shared by the initiating UE to the responding UE.

Alternatively, or in addition, the report may comprise a sidelink communication type indicated in the COT sharing indication, for example, a cast type of the COT information. The cast type may include but not limited to unicast, groupcast and broadcast.

Furthermore, in some example embodiments, if the report is associated with a plurality of COT sharing indications which include the COT sharing indication from the second terminal device 120, the first terminal device 110 may determine respective priorities of the plurality of COT sharing indications and may generate, based on the respective priorities, the report to indicate the respective priorities. In an example, the responding UE receives COT sharing information from multiple initiating UEs. The report may be transmitted in a UL MAC CE with multiple entries each corresponding to a COT sharing indication from an initiating UE.

In some embodiments, the report may include explicit indications of the respective priorities.

In some embodiments, the respective priorities may be indicated implicitly. The report may comprise a plurality of entries corresponding to the plurality of COT sharing indications respectively, and the plurality of entries is ordered based on the respective priorities of the plurality of COT sharing indications. For example, the multiple entries may be in a priority order from the highest to the lowest. The priority order may indicate the priority that the responding UE would like to use the COT sharing indications.

In some embodiments, the respective priorities of the plurality of COT sharing indications are determined based on respective channel access priority class (CAPC) values in the plurality of COT sharing indications. Alternatively, the respective priorities may be determined based on any other suitable manner, for example, based on the first terminal device 110’s implementation.

In the embodiments described above, the responding terminal device reports the COT sharing information to the network device. In this way, the network device may take the COT into consideration in allocating sidelink resources for the responding terminal device. Usage efficiency of the sidelink resources can be improved and thus performance of the sidelink communication can be improved.

In some embodiments, the first device may be the network device, and the second device may be the second terminal device. Accordingly, the first information may comprise a configuration of a resource pool for using by the first terminal device, and the second information comprises assistant information for COT sharing.

Referring to FIG. 3B, FIG. 3B shows a signaling flow 300B of COT sharing assistant information in accordance with some embodiments of the present disclosure.

As shown in FIG. 3B, in some example embodiments, the network device 130 may transmit (340) , to the first terminal device 110, a configuration of a resource pool for using by the first terminal device 110. Accordingly, the first terminal device 110 may receive (345) the configuration from the second terminal device 120.

Then, in some example embodiments, the first terminal device 110 may determine (350) whether at least one condition is met. If the at least one condition is met, the first terminal device 110 may transmit (355) , to the second terminal device 120, assistant information for COT sharing. Accordingly, the second terminal device 120 may receive (360) , from the first terminal device 110, the assistant information for COT sharing with the first terminal device 110. The assistant information may be used to assist the second terminal device 120 in sharing COT with the first terminal device 110 for example via a PC5 unicast link.

In an example, the condition may comprise that the configuration of the resource pool is a resource pool reconfiguration. For example, if the resource pool is re-configured via the network device 130, the responding UE may transmit the assistant information to the initiating UE.

Alternatively, or in addition, the condition may comprise that the configuration of the resource pool has a configured grant including but not limited to type 1 CG or type 2 CG. For example, if the type 1 CG or type 2 CG is configured by the network device 130, the responding UE may transmit the assistant information to the initiating UE.

Alternatively, or in addition, the condition may comprise that a resource allocation mode of the first terminal device is changed. For example, if the resource allocation mode may be switched from mode 1 to mode 2, or from mode 2 to mode 1, the responding UE may transmit the assistant information to the initiating UE.

Alternatively, or in addition, the condition may comprise that a resource scheduled by the network device 130 is not comprised in a resource block set of a COT previously shared by the second terminal device 120. For example, if for the previous COT sharing, the scheduled resource does not fall within the COT of the initiating UE, the responding UE may transmit the assistant information to the initiating UE.

In some example embodiments, the assistant information may include the configuration of the resource pool, for example, the resource pool configuration from the network device 130.

Alternatively, or in addition, the assistant information may include an index of a resource block set on which a consistent LBT is detected within the resource pool. For example, the assistant information may include the RB set index of which consistent LBT failure happens within the resource pool configured by the network device 130.

Alternatively, or in addition, the assistant information may include a configured grant corresponding to the configuration of the resource pool. The configured grant may be type 1 CG or type 2 CG. Furthermore, the assistant information may comprise an activation status of the configured grant, for example, whether the CG is activated or de activated.

The assistant information may be transmitted in any suitable signaling. In some example embodiments, the assistant information may be transmitted using an SL MAC CE or a PC5 RRC message.

In some example embodiments, the first terminal device 110 may receive, from the second terminal device 120, an indication to cancel a COT shared by the second terminal device previously. For example, once the initiating UE receives the assistant information from the responding UE, the initiating UE may send a COT sharing cancellation indication if the initiating UE has transmitted one COT previously.

Alternatively, or in addition, the first terminal device 110 may receive, from the second terminal device 120, an indication of successful reception of the assistant information. For example, once the initiating UE receives the assistant information from the responding UE, the initiating UE may send confirmation information to indicate successful reception.

In the embodiments described above, the responding terminal device provides the COT sharing assistant information to the initiating terminal device. In this way, the initiating terminal device may take the resource pool configuration into consideration in sharing the COT with the responding terminal device. Usage efficiency of the sidelink resources can be improved and thus performance of the sidelink communication can be improved.

Single carrier selection

Some example solutions on the COT sharing are described above. However, some issues remain pending. For example, if multiple carriers are configured and the terminal device has the CA capability, how to perform carrier selection for single carrier needs to be specified.

To this end, some embodiments of the present disclosure provide a solution for carrier selection/reselection in SL communication. Reference is made to FIG. 4, which illustrates a signaling flow 400 of carrier selection in accordance with some embodiments of the present disclosure. For the purposes of discussion, the signaling flow 400 will be discussed with reference to FIG. 1, for example, by using the network device 130. The network device 130 may communicate with a terminal device 410 which may be the first terminal device 110 or the second terminal device 120. In some embodiments, the terminal device 410 may be capable of carrier aggregation, for example, may operate as a UE with carrier aggregation capability.

As shown in FIG. 4, in some example embodiments, the network device 130 may transmit (420) , to the terminal device 410, a configuration indicating a plurality of carrier frequencies for sidelink communication of the terminal device. Accordingly, the terminal device 410 may receive (425) the configuration from the network device 130. In other words, the terminal device 410 is configured with multiple carrier frequencies.

In case that the terminal device 410 has the capability to perform transmission or reception among multiple sidelink frequencies and configured with multiple sidelink frequencies by the network device 130 and some condition is met, the terminal device 410 may select a single carrier frequency for data transmission. In some example embodiments, as shown in FIG. 4, the terminal device 410 may determine (430) whether a first condition is met. The first condition is associated with a first logical channel selected by the terminal device 410 or an activation status of the carrier aggregation for the terminal device 410. If the first condition is met, the terminal device 410 may select (435) a single carrier frequency for the sidelink communication.

In an example, the first condition may comprise that a destination identity of the first logical channel is indicated as compatible with non-carrier aggregation. For example, if the terminal device 410 has selected the logical channel of which the destination ID is associated with a Tx profile which indicates the backward compatible, the single carrier frequency may be selected.

Alternatively, or in addition, the first condition may comprise that a destination identity of the first logical channel corresponds to a unicast link with a peer terminal device incapable of carrier aggregation. For example, if the terminal device 410 has selected the logical channel of which the destination ID corresponding to the PC5 unicast link with a peer UE whose capability is CA incapable, the single carrier frequency may be selected.

Alternatively, or in addition, the first condition may comprise that a bearer corresponding to the first logical channel is deactivated for Packet Data Convergence Protocol (PDCP) duplication. For example, if the terminal device 410 has selected the logical channel of which the corresponding bearer configuration is set with PDCP duplication deactivation, the single carrier frequency may be selected.

Alternatively, or in addition, the first condition may comprise that only one frequency in a frequency list of the logical channel has a measured channel busy ratio (CBR) below a CBR reselection threshold. For example, if the terminal device 410 has selected the logical channel of which only one frequency within the frequency list whose CBR measurement result is below the CBR-Reselection threshold, the single carrier frequency may be selected.

Alternatively, or in addition, the first condition may comprise that the terminal device 410 is not configured with activation of the carrier aggregation. For example, if the network device 130 does not configure the terminal device 410 with activation of the carrier aggregation, the single carrier frequency may be selected.

In case that the terminal device 410 has the capability to perform transmission or reception among multiple sidelink frequencies and configured with multiple sidelink frequencies by the network device 130, the terminal device 410 has selected a single frequency for single or multiple MAC PDU transmission, and some condition is met, the terminal device 410 may reselect a single carrier frequency.

As shown in FIG. 4, in some example embodiments, if the terminal device 410 has selected (420) the signal carrier frequency for data transmission, the terminal device 410 may determine whether a second condition is met (440) . The second condition is associated with a second logical channel selected by the terminal device 410 or the activation status of the carrier aggregation for the terminal device 410. If the second condition is met, the terminal device 410 may perform (445) carrier reselection for the sidelink communication.

In an example, the second condition may comprise that a destination identity of the second logical channel is indicated as incompatible with non-carrier aggregation. For example, if the terminal device 410 has selected the logical channel of which the destination ID is associated with the Tx profile which indicates the backward incompatible, the carrier reselection may be performed.

Alternatively, or in addition, the second condition may comprise that a destination identity of the second logical channel corresponds to a unicast link with a peer terminal device capable of carrier aggregation. For example, if the terminal device 410 has selected the logical channel of which the destination ID corresponding to the PC5 unicast link with a peer terminal device whose capability is CA capable, the carrier reselection may be performed.

Alternatively, or in addition, the second condition may comprise that a bearer corresponding to the second logical channel is activated for PDCP duplication. For example, if the terminal device 410 has selected the logical channel of which the corresponding bearer configuration is set with PDCP duplication activation, the carrier reselection may be performed.

Alternatively, or in addition, the second condition may comprise that the selected single carrier frequency has a measured CBR above a CBR keeping threshold and at least one candidate carrier frequency of the second logical channel has a measured CBR below a CBR reselection threshold. For example, if the terminal device 410 has selected the logical channel of which the selected frequency whose CBR measurement result is above the CBR-Keeping threshold and other candidate frequencies whose CBR measurement result are below the CBR-Reselection threshold, the carrier reselection may be performed.

Alternatively, or in addition, the second condition may comprise that the terminal device is configured with activation of the carrier aggregation. For example, if the network device 130 configures the terminal device 410 with activation of the carrier aggregation, the terminal device 410 may perform the carrier aggregation and the carrier reselection may be performed.

For carrier aggregation, UE may select only one carrier even it has the CA capability. In this way, carrier selection procedure and reselection procedure are specified, which facilitates robust sidelink communication.

Destination determination

Another issue remains to be solved for the LCP procedure in sidelink communication. Table 1 shows an example procedure for LCP.

Table 1 An example procedure for LCP

where the field sl-Priority represents sidelink logical channel priority; the field sl-PrioritisedBitRate represents the sidelink Prioritized Bit Rate (sPBR) with a value in kiloBytes/s; the field sl-BucketSizeDuration represents the sidelink Bucket Size Duration (sBSD) ; the field sl-configuredGrantType1Allowed represents whether a configured grant Type 1 can be used for sidelink transmission; the field sl-AllowedCG-List represents the allowed configured grant (s) for sidelink transmission; the field sl-HARQ-FeedbackEnabled which sets whether the logical channel is allowed to be multiplexed with logical channel (s) .

Table 2 shows an example procedure for selection of logical channels in LCP.

Table 2 An example procedure for selection of logical channels

where the IE SL-BWP-DiscPoolConfig is used to configure UE specific NR sidelink discovery dedicated resource pool; the IE SL-BWP-DiscPoolConfigCommon is used to configure the cell-specific NR sidelink discovery dedicated resource pool. The field sl-DiscTxPoolScheduling indicates the resources by which the UE is allowed to transmit NR sidelink discover based on network scheduling on the configured BWP. The field sl-DiscTxPoolSelected indicates the resources by which the UE is allowed to transmit NR sidelink discover based resource selection on the configured BWP.

As can be seen from the procedure, to perform LCP, a destination is needed to be determined. If COT shared by the initiating UE is used, then how to determine the destination for the LCP needs to be specified. Some embodiments of the present disclosure propose a solution for the LCP procedure. For an LCP procedure performed at responding UE side, responding UE may check the cast type indicated within the COT. Then, the responding UE may decide whether to use source ID or destination ID indicated within the COT to perform LCP.

Reference is made to FIG. 5, which illustrates a signaling flow 500 of destination determination for an LCP procedure in accordance with some embodiments of the present disclosure. For the purposes of discussion, the signaling flow 500 will be discussed with reference to FIG. 1, for example, by using the first terminal device 110 and the second terminal device 120.

As shown in FIG. 5, the second terminal device 120 may transmit (510) , to the first terminal device 110, a COT sharing indication. Accordingly, the first terminal device 110 may receive (515) the COT sharing indication from the second terminal device 120.

If a sidelink grant is within a COT indicated in the COT sharing indication, the first terminal device 110 may select (520) a destination for LCP associated with the sidelink grant based on a communication type and an identity indicated in the COT sharing indication. The communication type may be referred to as the cast type including but not limited to unicast, groupcast, or broadcast.

In some example embodiments, LBT may be performed for the sidelink grant. For example, type 2A/2B LBT may be performed for the sidelink grant which is within the shared COT.

In some example embodiments, if the communication type is groupcast or broadcast, the first terminal device 110 may select the destination based on a destination identity indicated in the COT sharing indication. For example, if a new transmission associated with a sidelink grant is within the shared COT indicated by initiating UE and the cast type of the shared COT is set as groupcast or broadcast, the first terminal device 110 may select a destination associated with the destination ID indicated within the COT sharing indication.

In some example embodiments, if the communication type is unicast, the first terminal device 110 may select the destination based on a source identity indicated in the COT sharing indication. For example, the source UE ID in the COT sharing indication may indicate the initiating UE itself. In this example, if the new transmission associated with the sidelink grant is within the shared COT indicated by the initiating UE and if the cast type of the shared COT is unicast, and optionally if type 2A/2B LBT is performed for the sidelink grant which is within the shared COT, the first terminal device 110 may select a destination associated with the source UE ID indicated within the COT sharing indication.

In some embodiments, if the communication type is unicast, the first terminal device 110 may select the destination based on a destination identity indicated in the COT sharing indication. For example, the destination UE ID in the COT sharing indication may indicate the initiating UE itself. In this example, if the new transmission associated with the sidelink grant is within the shared COT indicated by the initiating UE and if the cast type of the shared COT is unicast, and optionally if type 2A/2B LBT is performed for the sidelink grant which is within the shared COT, the first terminal device 110 may select a destination associated with the destination UE ID indicated within the COT sharing indication.

In some embodiments, the first terminal device 110 may determine whether a first source identity indicated in the COT sharing indication matches with a second source identity of the first terminal device 110 corresponding to a unicast link. If the first source identity matches with the second source identity, the first terminal device 110 may select the destination based on the destination identity indicated in the COT sharing indication. In other words, the responding terminal device may check whether the source UE ID in the COT sharing information matches the responding terminal device itself.

In some example embodiments, if none destination is selected based on the communication type and the identity, the first terminal device 110 may transmit (525) , to the second terminal device 120, one or more destination identities maintained by the first terminal device for groupcast or broadcast. Accordingly, the second terminal device 120 may receive (530) the destination identities from the first terminal device 110. For example, a maintained interested destination ID list for groupcast and broadcast may be transmitted with in an SL MAC CE to the second terminal device 120.

Alternatively, or in addition, if none destination is selected based on the communication type and the identity, the first terminal device 110 may transmit (535) , to the second terminal device 120, a pair of a source identity and a destination identity for unicast. Accordingly, the second terminal device 120 may receive (530) , from the first terminal device 110, the pair of a source identity and a destination identity. For example, a source and destination ID pair for unicast transmission may be transmitted within the SL MAC CE.

As an example, if none destination can be selected associated with the sidelink grant within the shared COR indicated by initiating UE, an SL MAC CE may be transmitted towards the initiating UE to indicated at least one of the following information: maintained interested destination ID list for groupcast and broadcast, or source and destination ID pair for unicast transmission.

Configuration for backward compatibility

Another issue remains to be solved for the sidelink communication. For carrier aggregation, so far it is agreed to use transmission (Tx) profile to indicate whether one specific service has needs to be backward compatible. However, this information is passed from UE’s higher layer, for example, V2X layer, the network has no knowledge of this information so that cannot provide corresponding configuration. Therefore, how to obtain the configuration for backward compatibility needs to be specified. Some embodiments of the present disclosure propose a solution for configuration for backward compatibility.

Reference is then made to FIG. 6, which illustrates a signaling flow 600 of configuration for backward compatibility in accordance with some embodiments of the present disclosure. For the purposes of discussion, the signaling flow 600 will be discussed with reference to FIG. 1, for example, by using the network device 130. The network device 130 may communicate with a terminal device 601 which may be the first terminal device 110 or the second terminal device 120.

As shown in FIG. 6, the terminal device 601 may obtain (610) a transmission profile associated with a destination identity. The transmission profile indicates a compatibility of the destination identity with non-carrier aggregation. For example, the compatibility may refer to whether the destination identity is compatible or incompatible with non-carrier aggregation. In other words, the transmission profile may indicate whether the destination identity is compatible or incompatible with non-carrier aggregation.

The terminal device 601 may determine (615) whether the terminal device 601 has a sidelink configuration for the indicated compatibility. For example, if the indicated compatibility is that the destination identity is compatible with non-carrier aggregation, which is backward compatible, the terminal device 601 may determine whether it has the sidelink configuration for non-carrier aggregation.

If the sidelink configuration for the indicated compatibility is absent, the terminal device 601 may transmit (620) , to the network device 130, sidelink information to request the sidelink configuration. The siedlink information comprises the destination identity and the transmission profile.

In some example embodiments, if the terminal device 601 is in an idle state or an inactive state, the terminal device 601 may trigger a procedure for entering into a connected state with the network device 130. For example, the terminal device 601 may be triggered into an RRC_CONNECTED state and the SidelinkUEInformation message may be updated to include the destination ID and the associated transmission profile. In some example embodiments, if the terminal device 601 is in the connected state, the terminal device 601 may transmit the sidelink information to the network device 130.

In an example, the Tx profile associated with the destination ID indicated by upper layer may be set as backward compatible. Accordingly, if the terminal device 601 is in an RRC_CONNECTED state and has not acquired the configuration for backward compatibility, the SidelinkUEInformation message may be updated to include the destination ID and the associated transmission profile. Otherwise, if the terminal device 601 is in RRC_IDLE or RRC_INACTIVE state, the terminal device 601 may be triggered into RRC_CONNECTED state. After entering into the RRC_CONNECTED state, he SidelinkUEInformation message may be updated to include the destination ID and the associated transmission profile.

Accordingly, as shown in FIG. 6, the network device 130 may receive (625) the sidelink information from the terminal device 601. The network device 130 may determine whether to configure the terminal device 601 with the requested configuration for the indicated compatibility.

In some example embodiments, if the terminal device 601 fails in receiving the sidelink configuration for the indicated compatibility, the terminal device 601 may handle a sidelink transmission associated with the destination identity based on a connection state of the terminal device 601 with the network device 130. The connection state may be an RRC_CONNECTED state, an RRC_IDLE state, or an RRC_INACTIVE state.

In an example, if the terminal device is in a connected state with the network device, the terminal device 601 may forego the sidelink transmission. For example, if the terminal device 601 is in the RRC_CONNECTED state, the terminal device 601 may not transmit the sidelink data associated with the corresponding destination ID.

In another example, if the terminal device 601 is in the RRC_IDLE state or the RRC_INACTIVE state, the terminal device 601 may perform the sidelink transmission by using a default configuration for the determined compatibility. For example, the terminal device 601 may use a pre-configuration for the backward compatibility to transmit the sidelink date associated with the corresponding destination ID.

In some example embodiments, the terminal device 601 may receive, from the network device 130, a first sidelink configuration compatible with the non-carrier aggregation. Then, the terminal device 601 may deactivate PDCP duplication for a sidelink transmission associated with the destination identity and perform the sidelink transmission on a carrier frequency indicated in the first sidelink configuration. For example, if the terminal device 601 obtains the configuration which is only for backward compatibility, the terminal device 601 may deactivate PDCP duplication and perform transmission on the frequency which is included within the backward compatible configuration.

In some example embodiments, the terminal device 601 may receive, from the network device 130, a second sidelink configuration incompatible with the non-carrier aggregation. The terminal device 601 may activate PDCP duplication for the sidelink transmission associated with the destination identity and perform an original packet transmission and a duplicated packet transmission of the sidelink transmission on carrier frequencies indicated in the second sidelink configuration. For example, if the terminal device 601 obtains the configuration which is only for backward in-compatibility, the terminal device 601 may activate PDCP duplication and perform both original transmission and duplicated transmission on the frequency which is included within the backward incompatible configuration.

In some example embodiments, the terminal device 601 may receive, from the network device 130, a third sidelink configuration compatible with the non-carrier aggregation and a fourth sidelink configuration incompatible with the non-carrier aggregation. Accordingly, the terminal device 601 may activate PDCP duplication for a sidelink transmission associated with the destination identity. The terminal device 601 may perform an original packet transmission of the sidelink transmission on a carrier frequency indicated in the third sidelink configuration and perform a duplicated packet transmission of the sidelink transmission on a carrier frequency indicated in the fourth sidelink configuration. For example, if the terminal device 601 obtains the configuration for both backward compatible and backward in-compatible, the terminal device 601 may activate PDCP duplication and perform original transmission on the frequency which is included within the backward compatible configuration and perform the duplicated transmission on the frequency which is included within the backward incompatible configuration.

Frequency configuration

Reference is then made to FIG. 7, which illustrates a signaling flow 700 of a frequency configuration in accordance with some embodiments of the present disclosure. For the purposes of discussion, the signaling flow 700 will be discussed with reference to FIG. 1, for example, by using the network device 130. The network device 130 may communicate with a terminal device 701 which may be the first terminal device 110 or the second terminal device 120.

As shown in FIG. 7, the terminal device 701 may obtain (710) mapping between one or more Quality of Service flows and one or more frequencies. For example, an MAC layer of the terminal device 701 may receive the mapping from QoS flows to frequencies in a frequency list from an upper layer of the terminal device 701.

The terminal device 701 may transmit (715) the mapping to the network device 130 if the terminal device 701 is a connected state with the network device 130. For example, the terminal device 701 may report the mapping to the network device 130 if the terminal device 701 is RRC_CONNECTED state. For example, for Destination Layer 2 ID1, the frequencies “f1” and “f2” may be mapped to QoS flow 1, the frequencies “f2” and “f3” may be mapped to QoS flow 2, and the frequencies “f1” and “f4” may be mapped to QoS flow 3. Alternatively, the QoS flow reported to the network device 130 may be identified by QoS flow ID (QFI) , PC5 QoS identifier (PQI) or default priority. Accordingly, the network device 130 may receive (720) the mapping from the terminal device 701.

In some embodiments, the network device 130 may transmit (725) a configuration indicating a mapping between the destination layer 2 ID to one or more frequencies, for example, the frequency list. Accordingly, the terminal device 701 may receive (730) the configuration from the network device 130. For example, the configuration may indicate that the destination layer 2 ID 1 is mapped to the frequencies “f1” and “f2” .

Alternatively, in some embodiments, if the terminal device 701 is in RRC_IDLE state or INACTIVE state or out of coverage of the network device 130, the terminal device 701 may obtain (725) the frequency configuration via system information block (SIB) or a pre-configuration. For example, the terminal device 701 may firstly obtain a configuration of a full frequency list, e.g., with the frequencies “f1” , “f2” , “f3” , “f4” , “f5” . Then, the terminal device 701 may select one or more frequencies from the full frequency list. The selected one or more frequencies can serve all QoS flows of the correspondingly destination ID. As an example, the terminal device 701 may filter out a sub-list of which the frequency can serve all QoS flows of the correspondingly destination ID. For example, the frequencies “f1” , “f2” may be selected.

In this way, the carrier frequency for use can be determined. Robustness of sidelink communication can thus be improved.

Example methods

FIG. 8 illustrates a flowchart of a communication method 800 implemented at a first terminal device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 800 will be described from the perspective of the first terminal device 110 in FIG. 1.

At block 810, the first terminal device receives, from a first device, first information about resources for the first terminal device to perform sidelink communication; and

At block 820, the first terminal device transmits, to a second device, second information associated with the first information, and wherein one of the first and second devices comprises a second terminal device sharing a channel occupation time (COT) with the first terminal device, and the other one of the first and second devices comprises a network device.

In some example embodiments, the first device comprises the second terminal device, and the second device comprises the network device, and the first information comprises a COT sharing indication, and the second information comprises a report associated with the COT sharing indication.

In some example embodiments, the report is transmitted to the network device in accordance with at least one of the following determinations: that the first terminal device is to use a resource indicated in the COT sharing indication, that the first terminal device is in a connected state with the network device, that a resource block set indicated in the COT sharing indication is not comprised in a resource block set of a resource pool used by the first terminal device, that a consistent listen before talk (LBT) failure is detected on a resource block set of the resource pool used by the first terminal device, or that the first terminal device is operating in a predetermined resource allocation mode.

In some example embodiments, the first terminal device starts a timer upon detection of the consistent LBT failure; and transmits the report to the network device in response to expiration of the timer.

In some example embodiments, the report comprises at least one of: the device identification of the second terminal device, an index of a resource block set indicated in the COT sharing indication, an index of a slot indicated in the COT sharing indication, or a sidelink communication type indicated in the COT sharing indication.

In some example embodiments, the report is associated with a plurality of COT sharing indications comprising the COT sharing indication from the second terminal device, and the first terminal device determines respective priorities of the plurality of COT sharing indications; and generates, based on the respective priorities, the report to indicate the respective priorities.

In some example embodiments, the respective priorities of the plurality of COT sharing indications are determined based on respective channel access priority class (CAPC) values in the plurality of COT sharing indications.

In some example embodiments, the report comprises a plurality of entries corresponding to the plurality of COT sharing indications respectively, and the plurality of entries is ordered based on the respective priorities of the plurality of COT sharing indications.

In some example embodiments, the first device comprises the network device, and the second device comprises the second terminal device, and the first information comprises a configuration of a resource pool for using by the first terminal device, and the second information comprises assistant information for COT sharing.

In some example embodiments, the assistant information is transmitted to the second terminal device in accordance with at least one of the following determinations: that the configuration of the resource pool is a resource pool reconfiguration, that the configuration of the resource pool has a configured grant, that a resource allocation mode of the first terminal device is changed, or that a resource scheduled by the network device is not comprised in a resource block set of a COT previously shared by the second terminal device.

In some example embodiments, the assistant information comprises at least one of: the configuration of the resource pool, an index of a resource block set on which a consistent LBT is detected within the resource pool, a configured grant corresponding to the configuration of the resource pool, or an activation status of the configured grant.

In some example embodiments, the first terminal device receives, from the second terminal device, an indication to cancel a COT shared by the second terminal device previously, or receives, from the second terminal device, an indication of successful reception of the assistant information.

FIG. 9 illustrates a flowchart of a communication method 900 implemented at a second terminal device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 900 will be described from the perspective of the second terminal device 120 in FIG. 1.

At block 910, the second terminal device receives, from a first terminal device, assistant information for channel occupation time (COT) sharing with the first terminal device, and wherein the assistant information is associated with a configuration of a resource pool for using by the first terminal device.

In some example embodiments, the assistant information comprises at least one of: the configuration of the resource pool, an index of a resource block set on which a consistent LBT is detected within the resource pool, or a configured grant corresponding to the configuration of the resource pool, or an activation status of the configured grant.

In some example embodiments, the second terminal device transmits, to the first terminal device, an indication to cancel a COT shared by the second terminal device previously, or transmits, to the first terminal device, an indication of successful reception of the assistant information.

FIG. 10 illustrates a flowchart of a communication method 1000 implemented at a network device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 1000 will be described from the perspective of the network device 130 in FIG. 1.

At block 1010, the network device receives, from a first terminal device, a report associated with at least a channel occupation time (COT) sharing indication from a second terminal device.

In some example embodiments, the report is associated with a plurality of COT sharing indications comprising the COT sharing indication from the second terminal device, and the report comprises an indication of respective priorities of the plurality of COT sharing indications.

FIG. 11 illustrates a flowchart of a communication method 1100 implemented at a terminal device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 1100 will be described from the perspective of the terminal device 410 in FIG. 4.

At block 1110, the terminal device receives, from a network device, a configuration indicating a plurality of carrier frequencies for sidelink communication of the terminal device, wherein the terminal device is capable of carrier aggregation; and

At block 1120, in accordance with a determination that a first condition is met, the terminal device selects a single carrier frequency for the sidelink communication, wherein the first condition is associated with a first logical channel selected by the terminal device or an activation status of the carrier aggregation for the terminal device.

In some example embodiments, the first condition comprises at least one of: that a destination identity of the first logical channel is indicated as compatible with non-carrier aggregation, that a destination identity of the first logical channel corresponds to a unicast link with a peer terminal device incapable of carrier aggregation, that a bearer corresponding to the first logical channel is deactivated for Packet Data Convergence Protocol (PDCP) duplication, that only one frequency in a frequency list of the logical channel has a measured channel busy ratio (CBR) below a CBR reselection threshold, or that the terminal device is not configured with activation of the carrier aggregation.

In some example embodiments, in accordance with a determination that a second condition is met, the terminal device performs carrier reselection for the sidelink communication, wherein the second condition is associated with a second logical channel selected by the terminal device or the activation status of the carrier aggregation for the terminal device.

In some example embodiments, the second condition comprises at least one of: that a destination identity of the second logical channel is indicated as incompatible with non-carrier aggregation, that a destination identity of the second logical channel corresponds to a unicast link with a peer terminal device capable of carrier aggregation, that a bearer corresponding to the second logical channel is activated for PDCP duplication, that the selected single carrier frequency has a measured CBR above a CBR keeping threshold and at least one candidate carrier frequency of the second logical channel has a measured CBR below a CBR reselection threshold, or that the terminal device is configured with activation of the carrier aggregation.

FIG. 12 illustrates a flowchart of a communication method 1200 implemented at a first terminal device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 1200 will be described from the perspective of the first terminal device 110 in FIG. 1.

At block 1210, the first terminal device receives, from a second terminal device, a channel occupation time (COT) sharing indication; and

At block 1220, in accordance with a determination that a sidelink grant is within a COT indicated in the COT sharing indication, the first terminal device selects a destination for logical channel prioritization associated with the sidelink grant based on a communication type and an identity indicated in the COT sharing indication.

In some example embodiments, a listen before talk is performed for the sidelink grant.

In some example embodiments, in accordance with a determination that the communication type is groupcast or broadcast, the first terminal device selects the destination based on a destination identity indicated in the COT sharing indication.

In some example embodiments, in accordance with a determination that the communication type is unicast, the first terminal device selects the destination based on a source identity indicated in the COT sharing indication.

In some example embodiments, in accordance with a determination that the communication type is unicast, the first terminal device selects the destination based on a destination identity indicated in the COT sharing indication.

In some example embodiments, the first terminal device determines whether a first source identity indicated in the COT sharing indication matches with a second source identity of the first terminal device corresponding to a unicast link; and in accordance with a determination that the first source identity matches with the second source identity, the first terminal device selects the destination based on the destination identity indicated in the COT sharing indication.

In some example embodiments, in response to that none destination is selected based on the communication type and the identity, the first terminal device transmits to the second terminal device at least one of: one or more destination identities maintained by the first terminal device for groupcast or broadcast, or a pair of a source identity and a destination identity for unicast.

FIG. 13 illustrates a flowchart of a communication method 1300 implemented at a second terminal device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 1300 will be described from the perspective of the second terminal device 120 in FIG. 1.

At block 1310, the second terminal device transmits, to a first terminal device, a channel occupation time (COT) sharing indication; and

At block 1320, the second terminal device receives, from the first terminal device, at least one of: one or more destination identities maintained by the first terminal device for groupcast or broadcast, or a pair of a source identity and a destination identity for unicast.

FIG. 14 illustrates a flowchart of a communication method 1400 implemented at a terminal device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 1400 will be described from the perspective of the terminal device 601 in FIG. 6.

At block 1410, the terminal device obtains a transmission profile associated with a destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and

At block 1420, in accordance with an absence of a sidelink configuration for the indicated compatibility, the terminal device transmits, to a network device, sidelink information to request the sidelink configuration, the siedlink information comprising the destination identity and the transmission profile.

In some example embodiments, in accordance with a determination that the terminal device is in an idle state or an inactive state, the terminal device triggers a procedure for entering into a connected state with the network device; and in accordance with a determination that the terminal device is in the connected state, the terminal device transmits the sidelink information to the network device.

In some example embodiments, in accordance with a failure in receiving the sidelink configuration for the indicated compatibility, the terminal device handles a sidelink transmission associated with the destination identity based on a connection state of the terminal device with the network device.

In some example embodiments, the terminal device foregoes the sidelink transmission if the terminal device is in a connected state with the network device, or performs the sidelink transmission by using a default configuration for the determined compatibility.

In some example embodiments, the terminal device receives, from the network device, a first sidelink configuration compatible with the non-carrier aggregation; the terminal device deactivates Packet Data Convergence Protocol (PDCP) duplication for a sidelink transmission associated with the destination identity; and the terminal device performs the sidelink transmission on a carrier frequency indicated in the first sidelink configuration.

In some example embodiments, the terminal device receives, from the network device, a second sidelink configuration incompatible with the non-carrier aggregation; activate PDCP duplication for a sidelink transmission associated with the destination identity; and the terminal device performs an original packet transmission and a duplicated packet transmission of the sidelink transmission on carrier frequencies indicated in the second sidelink configuration.

In some example embodiments, the terminal device receives, from the network device, a third sidelink configuration compatible with the non-carrier aggregation and a fourth sidelink configuration incompatible with the non-carrier aggregation; the terminal device activates PDCP duplication for a sidelink transmission associated with the destination identity; perform an original packet transmission of the sidelink transmission on a carrier frequency indicated in the third sidelink configuration; and the terminal device performs a duplicated packet transmission of the sidelink transmission on a carrier frequency indicated in the fourth sidelink configuration.

FIG. 15 illustrates a flowchart of a communication method 1500 implemented at a network device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 1500 will be described from the perspective of the network device 130 in FIG. 1.

At block 1510, the network device receives, from a terminal device, sidelink information comprising a destination identity and a transmission profile asscioated with the destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation.

At block 1520, the network device determines, based on the sidelink information, that the terminal device requests a sidelink configuration for the indicated compatibility.

FIG. 16 is a simplified block diagram of a device 1600 that is suitable for implementing embodiments of the present disclosure. The device 1600 can be considered as a further example implementation of any of the devices as shown in FIG. 1. Accordingly, the device 1600 can be implemented at or as at least a part of the first terminal device 110, the second terminal device 120, or the network device 130.

As shown, the device 1600 includes a processor 1610, a memory 1620 coupled to the processor 1610, a suitable transceiver 1640 coupled to the processor 1610, and a communication interface coupled to the transceiver 1640. The memory 1620 stores at least a part of a program 1630. The transceiver 1640 may be for bidirectional communications or a unidirectional communication based on requirements. The transceiver 1640 may include at least one of a transmitter 1642 and a receiver 1644. The transmitter 1642 and the receiver 1644 may be functional modules or physical entities. The transceiver 1640 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2/Xn interface for bidirectional communications between eNBs/gNBs, S1/NG interface for communication between a Mobility Management Entity (MME) /Access and Mobility Management Function (AMF) /SGW/UPF and the eNB/gNB, Un interface for communication between the eNB/gNB and a relay node (RN) , or Uu interface for communication between the eNB/gNB and a terminal device.

The program 1630 is assumed to include program instructions that, when executed by the associated processor 1610, enable the device 1600 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to FIGS. 1 to 15. The embodiments herein may be implemented by computer software executable by the processor 1610 of the device 1600, or by hardware, or by a combination of software and hardware. The processor 1610 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 1610 and memory 1620 may form processing means 1650 adapted to implement various embodiments of the present disclosure.

The memory 1620 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 1620 is shown in the device 1600, there may be several physically distinct memory modules in the device 1600. The processor 1610 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 1600 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

According to embodiments of the present disclosure, a first terminal device comprising a circuitry is provided. The circuitry is configured to: receive, from a first device, first information about resources for the first terminal device to perform sidelink communication; and transmit, to a second device, second information associated with the first information, and wherein one of the first and second devices comprises a second terminal device sharing a channel occupation time (COT) with the first terminal device, and the other one of the first and second devices comprises a network device. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the first terminal device as discussed above.

According to embodiments of the present disclosure, a second terminal device comprising a circuitry is provided. The circuitry is configured to: receive, from a first terminal device, assistant information for channel occupation time (COT) sharing with the first terminal device, and wherein the assistant information is associated with a configuration of a resource pool for using by the first terminal device. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the second terminal device as discussed above.

According to embodiments of the present disclosure, a network device comprising a circuitry is provided. The circuitry is configured to: receive, from a first terminal device, a report associated with at least a channel occupation time (COT) sharing indication from a second terminal device. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the network device as discussed above.

According to embodiments of the present disclosure, a terminal device comprising a circuitry is provided. The circuitry is configured to: receive, from a network device, a configuration indicating a plurality of carrier frequencies for sidelink communication of the terminal device, wherein the terminal device is capable of carrier aggregation; and in accordance with a determination that a first condition is met, select a single carrier frequency for the sidelink communication, wherein the first condition is associated with a first logical channel selected by the terminal device or an activation status of the carrier aggregation for the terminal device. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the terminal device as discussed above.

According to embodiments of the present disclosure, a first terminal device comprising a circuitry is provided. The circuitry is configured to: receive, from a second terminal device, a channel occupation time (COT) sharing indication; and in accordance with a determination that a sidelink grant is within a COT indicated in the COT sharing indication, select a destination for logical channel prioritization associated with the sidelink grant based on a communication type and an identity indicated in the COT sharing indication. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the first terminal device as discussed above.

According to embodiments of the present disclosure, a second terminal device comprising a circuitry is provided. The circuitry is configured to: transmit, to a first terminal device, a channel occupation time (COT) sharing indication; and receive, from the first terminal device, at least one of: one or more destination identities maintained by the first terminal device for groupcast or broadcast, or a pair of a source identity and a destination identity for unicast. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the second terminal device as discussed above.

According to embodiments of the present disclosure, a terminal device comprising a circuitry is provided. The circuitry is configured to: obtain a transmission profile associated with a destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and in accordance with an absence of a sidelink configuration for the indicated compatibility, transmit, to a network device, sidelink information to request the sidelink configuration, the siedlink information comprising the destination identity and the transmission profile. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the terminal device as discussed above.

According to embodiments of the present disclosure, a network device comprising a circuitry is provided. The circuitry is configured to: receive, from a terminal device, sidelink information comprising a destination identity and a transmission profile asscioated with the destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and determine, based on the sidelink information, that the terminal device requests a sidelink configuration for the indicated compatibility. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the network device as discussed above.

The term “circuitry” used herein may refer to hardware circuits and/or combinations of hardware circuits and software. For example, the circuitry may be a combination of analog and/or digital hardware circuits with software/firmware. As a further example, the circuitry may be any portions of hardware processors with software including digital signal processor (s) , software, and memory (ies) that work together to cause an apparatus, such as a terminal device or a network device, to perform various functions. In a still further example, the circuitry may be hardware circuits and or processors, such as a microprocessor or a portion of a microprocessor, that requires software/firmware for operation, but the software may not be present when it is not needed for operation. As used herein, the term circuitry also covers an implementation of merely a hardware circuit or processor (s) or a portion of a hardware circuit or processor (s) and its (or their) accompanying software and/or firmware.

According to embodiments of the present disclosure, a first terminal apparatus is provided. The first terminal apparatus comprises means for receiving, from a first device, first information about resources for the first terminal device to perform sidelink communication; and means for transmitting, to a second device, second information associated with the first information, and means for wherein one of the first and second devices comprises a second terminal device sharing a channel occupation time (COT) with the first terminal device, and the other one of the first and second devices comprises a network device. In some embodiments, the first apparatus may comprise means for performing the respective operations of the method 800. In some example embodiments, the first apparatus may further comprise means for performing other operations in some example embodiments of the method 800. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

According to embodiments of the present disclosure, a second terminal apparatus is provided. The second terminal apparatus comprises means for receiving, from a first terminal device, assistant information for channel occupation time (COT) sharing with the first terminal device, and means for wherein the assistant information is associated with a configuration of a resource pool for using by the first terminal device. In some embodiments, the second apparatus may comprise means for performing the respective operations of the method 900. In some example embodiments, the second apparatus may further comprise means for performing other operations in some example embodiments of the method 900. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

According to embodiments of the present disclosure, a network apparatus is provided. The network apparatus comprises means for receiving, from a first terminal device, a report associated with at least a channel occupation time (COT) sharing indication from a second terminal device. In some embodiments, the third apparatus may comprise means for performing the respective operations of the method 1000. In some example embodiments, the third apparatus may further comprise means for performing other operations in some example embodiments of the method 1000. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

According to embodiments of the present disclosure, a terminal apparatus is provided. The terminal apparatus comprises means for receiving, from a network device, a configuration indicating a plurality of carrier frequencies for sidelink communication of the terminal device, wherein the terminal device is capable of carrier aggregation; and means for in accordance with a determination that a first condition is met, selecting a single carrier frequency for the sidelink communication, wherein the first condition is associated with a first logical channel selected by the terminal device or an activation status of the carrier aggregation for the terminal device. In some embodiments, the fourth apparatus may comprise means for performing the respective operations of the method 1100. In some example embodiments, the fourth apparatus may further comprise means for performing other operations in some example embodiments of the method 1100. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

According to embodiments of the present disclosure, a first terminal apparatus is provided. The first terminal apparatus comprises means for receiving, from a second terminal device, a channel occupation time (COT) sharing indication; and means for in accordance with a determination that a sidelink grant is within a COT indicated in the COT sharing indication, selecting a destination for logical channel prioritization associated with the sidelink grant based on a communication type and an identity indicated in the COT sharing indication. In some embodiments, the fifth apparatus may comprise means for performing the respective operations of the method 1200. In some example embodiments, the fifth apparatus may further comprise means for performing other operations in some example embodiments of the method 1200. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

According to embodiments of the present disclosure, a second terminal apparatus is provided. The second terminal apparatus comprises means for transmitting, to a first terminal device, a channel occupation time (COT) sharing indication; and means for receiving, from the first terminal device, at least one of: means for one or more destination identities maintained by the first terminal device for groupcast or broadcast, or means for a pair of a source identity and a destination identity for unicast. In some embodiments, the sixth apparatus may comprise means for performing the respective operations of the method 1300. In some example embodiments, the sixth apparatus may further comprise means for performing other operations in some example embodiments of the method 1300. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

According to embodiments of the present disclosure, a terminal apparatus is provided. The terminal apparatus comprises means for obtaining a transmission profile associated with a destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and means for in accordance with an absence of a sidelink configuration for the indicated compatibility, transmitting, to a network device, sidelink information to request the sidelink configuration, the siedlink information comprising the destination identity and the transmission profile. In some embodiments, the seventh apparatus may comprise means for performing the respective operations of the method 1400. In some example embodiments, the seventh apparatus may further comprise means for performing other operations in some example embodiments of the method 1400. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

According to embodiments of the present disclosure, a network apparatus is provided. The network apparatus comprises means for receiving, from a terminal device, sidelink information comprising a destination identity and a transmission profile asscioated with the destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and means for determining, based on the sidelink information, that the terminal device requests a sidelink configuration for the indicated compatibility. In some embodiments, the eighth apparatus may comprise means for performing the respective operations of the method 1500. In some example embodiments, the eighth apparatus may further comprise means for performing other operations in some example embodiments of the method 1500. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In summary, embodiments of the present disclosure provide the following aspects.

In an aspect, it is proposed a first terminal device comprising: a processor configured to cause the first terminal device to: receive, from a first device, first information about resources for the first terminal device to perform sidelink communication; and transmit, to a second device, second information associated with the first information, and wherein one of the first and second devices comprises a second terminal device sharing a channel occupation time (COT) with the first terminal device, and the other one of the first and second devices comprises a network device.

In some embodiments, the first device comprises the second terminal device, and the second device comprises the network device, and the first information comprises a COT sharing indication, and the second information comprises a report associated with the COT sharing indication.

In some embodiments, the report is transmitted to the network device in accordance with at least one of the following determinations: that the first terminal device is to use a resource indicated in the COT sharing indication, that the first terminal device is in a connected state with the network device, that a resource block set indicated in the COT sharing indication is not comprised in a resource block set of a resource pool used by the first terminal device, that a consistent listen before talk (LBT) failure is detected on a resource block set of the resource pool used by the first terminal device, or that the first terminal device is operating in a predetermined resource allocation mode.

In some embodiments, the first terminal device is further caused to: start a timer upon detection of the consistent LBT failure; and transmit the report to the network device in response to expiration of the timer.

In some embodiments, the report comprises at least one of: the device identification of the second terminal device, an index of a resource block set indicated in the COT sharing indication, an index of a slot indicated in the COT sharing indication, or a sidelink communication type indicated in the COT sharing indication.

In some embodiments, the report is associated with a plurality of COT sharing indications comprising the COT sharing indication from the second terminal device, and the first terminal device is further caused to: determine respective priorities of the plurality of COT sharing indications; and generate, based on the respective priorities, the report to indicate the respective priorities.

In some embodiments, the respective priorities of the plurality of COT sharing indications are determined based on respective channel access priority class (CAPC) values in the plurality of COT sharing indications.

In some embodiments, the report comprises a plurality of entries corresponding to the plurality of COT sharing indications respectively, and the plurality of entries is ordered based on the respective priorities of the plurality of COT sharing indications.

In some embodiments, the first device comprises the network device, and the second device comprises the second terminal device, and the first information comprises a configuration of a resource pool for using by the first terminal device, and the second information comprises assistant information for COT sharing.

In some embodiments, the assistant information is transmitted to the second terminal device in accordance with at least one of the following determinations: that the configuration of the resource pool is a resource pool reconfiguration, that the configuration of the resource pool has a configured grant, that a resource allocation mode of the first terminal device is changed, or that a resource scheduled by the network device is not comprised in a resource block set of a COT previously shared by the second terminal device.

In some embodiments, the assistant information comprises at least one of: the configuration of the resource pool, an index of a resource block set on which a consistent LBT is detected within the resource pool, a configured grant corresponding to the configuration of the resource pool, or an activation status of the configured grant.

In some embodiments, the first terminal device is further caused to perform at least one: receiving, from the second terminal device, an indication to cancel a COT shared by the second terminal device previously, or receiving, from the second terminal device, an indication of successful reception of the assistant information.

In an aspect, it is proposed a second terminal device comprising: a processor configured to cause the second terminal device to: receive, from a first terminal device, assistant information for channel occupation time (COT) sharing with the first terminal device, and wherein the assistant information is associated with a configuration of a resource pool for using by the first terminal device.

In some embodiments, the assistant information comprises at least one of: the configuration of the resource pool, an index of a resource block set on which a consistent LBT is detected within the resource pool, or a configured grant corresponding to the configuration of the resource pool, or an activation status of the configured grant.

In some embodiments, the second terminal device is further caused to perform at least one: transmitting, to the first terminal device, an indication to cancel a COT shared by the second terminal device previously, or transmitting, to the first terminal device, an indication of successful reception of the assistant information.

In an aspect, it is proposed a network device comprising: a processor configured to cause the network device to: receive, from a first terminal device, a report associated with at least a channel occupation time (COT) sharing indication from a second terminal device.

In some embodiments, the report is associated with a plurality of COT sharing indications comprising the COT sharing indication from the second terminal device, and the report comprises an indication of respective priorities of the plurality of COT sharing indications.

In an aspect, it is proposed a terminal device comprising: a processor configured to cause the terminal device to: receive, from a network device, a configuration indicating a plurality of carrier frequencies for sidelink communication of the terminal device, wherein the terminal device is capable of carrier aggregation; and in accordance with a determination that a first condition is met, select a single carrier frequency for the sidelink communication, wherein the first condition is associated with a first logical channel selected by the terminal device or an activation status of the carrier aggregation for the terminal device.

In some embodiments, the first condition comprises at least one of: that a destination identity of the first logical channel is indicated as compatible with non-carrier aggregation, that a destination identity of the first logical channel corresponds to a unicast link with a peer terminal device incapable of carrier aggregation, that a bearer corresponding to the first logical channel is deactivated for Packet Data Convergence Protocol (PDCP) duplication, that only one frequency in a frequency list of the logical channel has a measured channel busy ratio (CBR) below a CBR reselection threshold, or that the terminal device is not configured with activation of the carrier aggregation.

In some embodiments, the terminal device is further caused to: in accordance with a determination that a second condition is met, perform carrier reselection for the sidelink communication, wherein the second condition is associated with a second logical channel selected by the terminal device or the activation status of the carrier aggregation for the terminal device.

In some embodiments, the second condition comprises at least one of: that a destination identity of the second logical channel is indicated as incompatible with non-carrier aggregation, that a destination identity of the second logical channel corresponds to a unicast link with a peer terminal device capable of carrier aggregation, that a bearer corresponding to the second logical channel is activated for PDCP duplication, that the selected single carrier frequency has a measured CBR above a CBR keeping threshold and at least one candidate carrier frequency of the second logical channel has a measured CBR below a CBR reselection threshold, or that the terminal device is configured with activation of the carrier aggregation.

In an aspect, it is proposed a first terminal device comprising: a processor configured to cause the first terminal device to: receive, from a second terminal device, a channel occupation time (COT) sharing indication; and in accordance with a determination that a sidelink grant is within a COT indicated in the COT sharing indication, select a destination for logical channel prioritization associated with the sidelink grant based on a communication type and an identity indicated in the COT sharing indication.

In some embodiments, a listen before talk is performed for the sidelink grant.

In some embodiments, the first terminal device is further caused to: in accordance with a determination that the communication type is groupcast or broadcast, select the destination based on a destination identity indicated in the COT sharing indication.

In some embodiments, the first terminal device is further caused to: in accordance with a determination that the communication type is unicast, select the destination based on a source identity indicated in the COT sharing indication.

In some embodiments, the first terminal device is further caused to: in accordance with a determination that the communication type is unicast, select the destination based on a destination identity indicated in the COT sharing indication.

In some embodiments, the first terminal device is further caused to: determine whether a first source identity indicated in the COT sharing indication matches with a second source identity of the first terminal device corresponding to a unicast link; and in accordance with a determination that the first source identity matches with the second source identity, select the destination based on the destination identity indicated in the COT sharing indication.

In some embodiments, the first terminal device is further caused to: in response to that none destination is selected based on the communication type and the identity, transmit to the second terminal device at least one of: one or more destination identities maintained by the first terminal device for groupcast or broadcast, or a pair of a source identity and a destination identity for unicast.

In an aspect, it is proposed a second terminal device comprising: a processor configured to cause the second terminal device to: transmit, to a first terminal device, a channel occupation time (COT) sharing indication; and receive, from the first terminal device, at least one of: one or more destination identities maintained by the first terminal device for groupcast or broadcast, or a pair of a source identity and a destination identity for unicast.

In an aspect, it is proposed a terminal device comprising: a processor configured to cause the terminal device to: obtain a transmission profile associated with a destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and in accordance with an absence of a sidelink configuration for the indicated compatibility, transmit, to a network device, sidelink information to request the sidelink configuration, the siedlink information comprising the destination identity and the transmission profile.

In some embodiments, the terminal device is further caused to: in accordance with a determination that the terminal device is in an idle state or an inactive state, trigger a procedure for entering into a connected state with the network device; and in accordance with a determination that the terminal device is in the connected state, transmit the sidelink information to the network device.

In some embodiments, the terminal device is further caused to: in accordance with a failure in receiving the sidelink configuration for the indicated compatibility, handle a sidelink transmission associated with the destination identity based on a connection state of the terminal device with the network device.

In some embodiments, the terminal device is further caused to: forego the sidelink transmission if the terminal device is in a connected state with the network device, or perform the sidelink transmission by using a default configuration for the determined compatibility.

In some embodiments, the terminal device is further caused to: receive, from the network device, a first sidelink configuration compatible with the non-carrier aggregation; deactivate Packet Data Convergence Protocol (PDCP) duplication for a sidelink transmission associated with the destination identity; and perform the sidelink transmission on a carrier frequency indicated in the first sidelink configuration.

In some embodiments, the terminal device is further caused to: receive, from the network device, a second sidelink configuration incompatible with the non-carrier aggregation; activate PDCP duplication for a sidelink transmission associated with the destination identity; and perform an original packet transmission and a duplicated packet transmission of the sidelink transmission on carrier frequencies indicated in the second sidelink configuration.

In some embodiments, the terminal device is further caused to: receive, from the network device, a third sidelink configuration compatible with the non-carrier aggregation and a fourth sidelink configuration incompatible with the non-carrier aggregation; activate PDCP duplication for a sidelink transmission associated with the destination identity; perform an original packet transmission of the sidelink transmission on a carrier frequency indicated in the third sidelink configuration; and perform a duplicated packet transmission of the sidelink transmission on a carrier frequency indicated in the fourth sidelink configuration.

In an aspect, it is proposed a network device comprising: a processor configured to cause the terminal device to: receive, from a terminal device, sidelink information comprising a destination identity and a transmission profile asscioated with the destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and determine, based on the sidelink information, that the terminal device requests a sidelink configuration for the indicated compatibility.

In an aspect, a first terminal device comprises: at least one processor; and at least one memory coupled to the at least one processor and storing instructions thereon, the instructions, when executed by the at least one processor, causing the device to perform the method implemented by the first terminal device discussed above.

In an aspect, a second terminal device comprises: at least one processor; and at least one memory coupled to the at least one processor and storing instructions thereon, the instructions, when executed by the at least one processor, causing the device to perform the method implemented by the second terminal device discussed above.

In an aspect, a network device comprises: at least one processor; and at least one memory coupled to the at least one processor and storing instructions thereon, the instructions, when executed by the at least one processor, causing the device to perform the method implemented by the network device discussed above.

In an aspect, a terminal device comprises: at least one processor; and at least one memory coupled to the at least one processor and storing instructions thereon, the instructions, when executed by the at least one processor, causing the device to perform the method implemented by the terminal device discussed above.

In an aspect, a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the first terminal device discussed above.

In an aspect, a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the second terminal device discussed above.

In an aspect, a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the network device discussed above.

In an aspect, a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the terminal device discussed above.

In an aspect, a computer program comprising instructions, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the first terminal device discussed above.

In an aspect, a computer program comprising instructions, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the second terminal device discussed above.

In an aspect, a computer program comprising instructions, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the network device discussed above.

In an aspect, a computer program comprising instructions, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the terminal device discussed above.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to FIGS. 1 to 16. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine readable medium, which may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A first terminal device comprising:

a processor configured to cause the first terminal device to:

receive, from a first device, first information about resources for the first terminal device to perform sidelink communication; and

transmit, to a second device, second information associated with the first information, and

wherein one of the first and second devices comprises a second terminal device sharing a channel occupation time (COT) with the first terminal device, and the other one of the first and second devices comprises a network device.
The first terminal device of claim 1, wherein the first device comprises the second terminal device, and the second device comprises the network device, and

the first information comprises a COT sharing indication, and the second information comprises a report associated with the COT sharing indication.
The first terminal device of claim 2, wherein the report is transmitted to the network device in accordance with at least one of the following determinations:

that the first terminal device is to use a resource indicated in the COT sharing indication,

that the first terminal device is in a connected state with the network device,

that a resource block set indicated in the COT sharing indication is not comprised in a resource block set of a resource pool used by the first terminal device,

that a consistent listen before talk (LBT) failure is detected on a resource block set of the resource pool used by the first terminal device, or

that the first terminal device is operating in a predetermined resource allocation mode.
The first terminal device of claim 2, wherein the report comprises at least one of:

the device identification of the second terminal device,

an index of a resource block set indicated in the COT sharing indication,

an index of a slot indicated in the COT sharing indication, or

a sidelink communication type indicated in the COT sharing indication.
The first terminal device of claim 2, wherein the report is associated with a plurality of COT sharing indications comprising the COT sharing indication from the second terminal device, and the first terminal device is further caused to:

determine respective priorities of the plurality of COT sharing indications; and

generate, based on the respective priorities, the report to indicate the respective priorities.
The first terminal device of claim 1, wherein the first device comprises the network device, and the second device comprises the second terminal device, and

the first information comprises a configuration of a resource pool for using by the first terminal device, and the second information comprises assistant information for COT sharing, and

the assistant information is transmitted to the second terminal device in accordance with at least one of the following determinations:

that the configuration of the resource pool is a resource pool reconfiguration,

that the configuration of the resource pool has a configured grant,

that a resource allocation mode of the first terminal device is changed, or

that a resource scheduled by the network device is not comprised in a resource block set of a COT previously shared by the second terminal device.
The first terminal device of claim 6, wherein the assistant information comprises at least one of:

the configuration of the resource pool,

an index of a resource block set on which a consistent LBT is detected within the resource pool,

a configured grant corresponding to the configuration of the resource pool, or

an activation status of the configured grant.
A terminal device comprising:

a processor configured to cause the terminal device to:

receive, from a network device, a configuration indicating a plurality of carrier frequencies for sidelink communication of the terminal device, wherein the terminal device is capable of carrier aggregation; and

in accordance with a determination that a first condition is met, select a single carrier frequency for the sidelink communication, wherein the first condition is associated with a first logical channel selected by the terminal device or an activation status of the carrier aggregation for the terminal device.
The terminal device of claim 8, wherein the first condition comprises at least one of:

that a destination identity of the first logical channel is indicated as compatible with non-carrier aggregation,

that a destination identity of the first logical channel corresponds to a unicast link with a peer terminal device incapable of carrier aggregation,

that a bearer corresponding to the first logical channel is deactivated for Packet Data Convergence Protocol (PDCP) duplication,

that only one frequency in a frequency list of the logical channel has a measured channel busy ratio (CBR) below a CBR reselection threshold, or

that the terminal device is not configured with activation of the carrier aggregation.
The terminal device of claim 8, wherein the terminal device is further caused to:

in accordance with a determination that a second condition is met, perform carrier reselection for the sidelink communication, wherein the second condition is associated with a second logical channel selected by the terminal device or the activation status of the carrier aggregation for the terminal device.
The terminal device of claim 10, wherein the second condition comprises at least one of:

that a destination identity of the second logical channel is indicated as incompatible with non-carrier aggregation,

that a destination identity of the second logical channel corresponds to a unicast link with a peer terminal device capable of carrier aggregation,

that a bearer corresponding to the second logical channel is activated for PDCP duplication,

that the selected single carrier frequency has a measured CBR above a CBR keeping threshold and at least one candidate carrier frequency of the second logical channel has a measured CBR below a CBR reselection threshold, or

that the terminal device is configured with activation of the carrier aggregation.
A first terminal device comprising:

a processor configured to cause the first terminal device to:

receive, from a second terminal device, a channel occupation time (COT) sharing indication; and

in accordance with a determination that a sidelink grant is within a COT indicated in the COT sharing indication, select a destination for logical channel prioritization associated with the sidelink grant based on a communication type and an identity indicated in the COT sharing indication.
The first terminal device of claim 12, wherein the first terminal device is further caused to:

in accordance with a determination that the communication type is unicast, determine whether a first source identity indicated in the COT sharing indication matches with a second source identity of the first terminal device corresponding to a unicast link; and

in accordance with a determination that the first source identity matches with the second source identity, select the destination based on a destination identity indicated in the COT sharing indication.
The first terminal device of claim 12, wherein the first terminal device is further caused to:

in response to that none destination is selected based on the communication type and the identity, transmit to the second terminal device at least one of:

one or more destination identities maintained by the first terminal device for groupcast or broadcast, or

a pair of a source identity and a destination identity for unicast.
A terminal device comprising:

a processor configured to cause the terminal device to:

obtain a transmission profile associated with a destination identity, wherein the transmission profile indicates a compatibility of the destination identity with non-carrier aggregation; and

in accordance with an absence of a sidelink configuration for the indicated compatibility, transmit, to a network device, sidelink information to request the sidelink configuration, the siedlink information comprising the destination identity and the transmission profile.
The terminal device of claim 15, wherein the terminal device is further caused to:

in accordance with a determination that the terminal device is in an idle state or an inactive state, trigger a procedure for entering into a connected state with the network device; and

in accordance with a determination that the terminal device is in the connected state, transmit the sidelink information to the network device.
The terminal device of claim 15, wherein the terminal device is further caused to:

in accordance with a failure in receiving the sidelink configuration for the indicated compatibility, handle a sidelink transmission associated with the destination identity based on a connection state of the terminal device with the network device.
The terminal device of claim 15, wherein the terminal device is further caused to:

receive, from the network device, a first sidelink configuration compatible with the non-carrier aggregation;

deactivate Packet Data Convergence Protocol (PDCP) duplication for a sidelink transmission associated with the destination identity; and

perform the sidelink transmission on a carrier frequency indicated in the first sidelink configuration.
The terminal device of claim 15, wherein the terminal device is further caused to:

receive, from the network device, a second sidelink configuration incompatible with the non-carrier aggregation;

activate PDCP duplication for a sidelink transmission associated with the destination identity; and

perform an original packet transmission and a duplicated packet transmission of the sidelink transmission on carrier frequencies indicated in the second sidelink configuration.
The terminal device of claim 15, wherein the terminal device is further caused to:

receive, from the network device, a third sidelink configuration compatible with the non-carrier aggregation and a fourth sidelink configuration incompatible with the non-carrier aggregation;

activate PDCP duplication for a sidelink transmission associated with the destination identity;

perform an original packet transmission of the sidelink transmission on a carrier frequency indicated in the third sidelink configuration; and

perform a duplicated packet transmission of the sidelink transmission on a carrier frequency indicated in the fourth sidelink configuration.