Sidelink communication method, device, chip, and computer storage medium

Abstract

The present disclosure provides a sidelink communication method, comprising: sending a carrier aggregation indicator, wherein the carrier aggregation indicator is used for indicating a primary carrier and a secondary carrier in sidelink carrier aggregation; and receiving a message indicating that configuration of the primary carrier and the secondary carrier is complete, wherein the message indicating that configuration of the primary carrier and the secondary carrier is complete is returned by a node that has received the carrier aggregation indicator.

Description

Side link communication method, device, chip and computer storage medium Technical Field

[0001] The present disclosure relates to the field of wireless communications, and in particular to a sidelink communication method, a resource reselection method in sidelink communication, a carrier reselection method in sidelink communication, and a device, a chip, and a computer-readable storage medium in a sidelink communication system. Background Art

[0002] Licensed carriers (LCs) or authorized spectrum refer to frequency bands designated and allocated by the government or relevant agencies to specific users or operators. Users or operators require permission or authorization to use these frequency bands for communications. Licensed carriers typically require payment, and users must comply with specific regulations and spectrum usage conditions. For example, wireless communication frequency bands used by mobile operators, such as LTE and 5G spectrum, are typically licensed spectrum. The advantage of licensed spectrum is that it has certain protection and management mechanisms that ensure the rational allocation of spectrum resources and interference-free operation.

[0003] Unlicensed carriers or unlicensed spectrum refers to frequency bands that are not exclusively used by specific users or operators and can be used freely by any user under specified conditions, such as the 2.4GHz and 5GHz bands used in Wi-Fi technology. The use of unlicensed carriers does not require a license or authorization, but must comply with specific technical standards and regulations to avoid interfering with the communications of other users. Unlicensed spectrum is generally used to provide short-range, low-power communications, such as Wi-Fi and (Bluetooth), etc.

[0004] Licensed carriers and unlicensed carriers are two different types of carriers used for carrier aggregation in wireless communications. Carrier aggregation technology can simultaneously utilize licensed carriers and unlicensed carriers to improve the bandwidth and performance of wireless communication systems. By bundling multiple licensed carriers and / or unlicensed carriers together, the total available bandwidth can be increased, and data transmission rates and capacity can be improved. Carrier aggregation technology is commonly used in new-generation mobile communication standards such as LTE-Advanced (LTE-A) and 5G, and is also used in wireless broadband communications (such as Wi-Fi). Carrier aggregation can flexibly combine different types of carriers to meet different communication needs and optimize user experience.

[0005] In sidelink communications, relevant technologies and / or standards lack consensus and protocol-related provisions for the enhancement of unlicensed carriers in carrier aggregation, resulting in the unlicensed carriers not being fully utilized and enhanced in the carrier aggregation function in sidelink communication scenarios.

[0006] Summary of the Invention

[0007] To at least overcome the aforementioned technical issues, the present disclosure provides a sidelink communication method, a resource reselection method in sidelink communication, a carrier reselection method in sidelink communication, a device, a chip, and a computer-readable storage medium in a sidelink communication system. This achieves the purpose of enhancing unlicensed carriers in carrier aggregation for sidelink communication.

[0008] According to one aspect of the present disclosure, there is provided a sidelink communication method, comprising:

[0009] sending a carrier aggregation indicator, wherein the carrier aggregation indicator is used to indicate a primary carrier and a secondary carrier in a sidelink carrier aggregation; and

[0010] A message indicating that the configuration of the primary carrier and the secondary carrier is completed is received, wherein the message indicating that the configuration of the primary carrier and the secondary carrier is completed is returned by a node that receives the carrier aggregation indicator.

[0011] According to one aspect of the present disclosure, a resource reselection method in sidelink communication is provided, comprising:

[0012] Configuring one or more first listen-before-send (LBT) failure counters under carrier aggregation (CA), where the first LBT failure counters are configured to record a number of LBT failures occurring under the CA, and the first LBT failure counters correspond to a first threshold;

[0013] configuring a second LBT failure counter under non-CA, wherein the second LBT failure counter is configured to record the number of LBT failures occurring under the non-CA, wherein the second LBT failure counter corresponds to a second threshold, and the first threshold is greater than the second threshold; and

[0014] When the value of the first LBT failure counter reaches the first threshold, resource reselection is performed.

[0015] According to one aspect of the present disclosure, a carrier reselection method in sidelink communication is provided, including:

[0016] Receive a listen-before-send (LBT) failure message for the target carrier; and

[0017] In response to the LBT failure message matching a preset condition, performing carrier reselection for the target carrier;

[0018] The preset conditions include:

[0019] An LBT failure occurs for the first time on the target carrier; or

[0020] Consecutive LBT failures occur on the target carrier.

[0021] According to one aspect of the present disclosure, a sidelink communication method is provided, which is performed by a first node and includes:

[0022] sidelink control information SCI signaling is configured by the first node in the sidelink communication, the SCI signaling indicating resources for transmitting a physical sidelink feedback channel PSFCH by the second node in the sidelink communication,

[0023] The PSFCH resource is transmitted by the second node based on a physical sidelink shared channel PSSCH transmitted by the first node;

[0024] The resources used for the PSFCH are different from the resources used for the PSSCH.

[0025] According to one aspect of the present disclosure, a sidelink communication method is provided, which is performed by a first node and includes:

[0026] transmitting, by the first node in the sidelink communication, sidelink control information SCI signaling to the second node in the sidelink communication, the SCI signaling being carried by a first carrier,

[0027] The SCI signaling includes the channel occupancy time COT on the second carrier and a cell index or a carrier index associated with the second carrier.

[0028] According to one aspect of the present disclosure, a sidelink communication method, performed by a first node, includes:

[0029] preparing, by the first node in the sidelink communication, control signaling associated with the sidelink communication;

[0030] Transmitting, by the first node, the control signaling to the second node in the sidelink communication to indicate that the listen-before-talk (LBT) fails;

[0031] The control signaling is side link control information SCI signaling, and the SCI signaling includes an index of a resource block set RB set that is unavailable due to the LBT failure.

[0032] According to one aspect of the present disclosure, a device in a sidelink communication system is provided, wherein the device is configured to execute the method of any embodiment of the present disclosure.

[0033] According to one aspect of the present disclosure, a chip is provided, comprising: a processor configured to call and run a computer program stored in a memory, so that a device in which the chip is installed executes a method of an embodiment of any aspect of the present disclosure.

[0034] According to one aspect of the present disclosure, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program enables a computer to execute the method of the embodiments of any aspect of the present disclosure.

[0035] According to one aspect of the present disclosure, a computer program product is provided, comprising a computer program, wherein the computer program enables a computer to execute the method of any embodiment of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present disclosure or related technologies, the following drawings will be briefly introduced in the embodiments. Obviously, the drawings are only some embodiments of the present disclosure, and ordinary technicians in this field can derive other drawings based on these drawings without inventive work.

[0037] FIG1 illustrates a schematic diagram of an exemplary cellular network according to some embodiments of the present disclosure.

[0038] FIG2 illustrates a schematic diagram of an exemplary radio access network RAN ​​according to some embodiments of the present disclosure.

[0039] FIG3A illustrates a schematic flowchart of a sidelink communication method according to some embodiments of the present disclosure.

[0040] FIG3B illustrates a schematic diagram of exemplary signaling interactions between a first node and a second node in sidelink communication according to some embodiments of the present disclosure.

[0041] FIG3C illustrates a schematic flowchart of a resource reselection method in sidelink communication according to some embodiments of the present disclosure.

[0042] FIG3D illustrates a schematic flowchart of a carrier reselection method in sidelink communication according to some embodiments of the present disclosure.

[0043] FIG4A illustrates a schematic flowchart of a sidelink communication method performed by a first node according to some embodiments of the present disclosure.

[0044] FIG4B illustrates a schematic diagram of exemplary signaling interactions between a first node and a second node in sidelink communication according to some embodiments of the present disclosure.

[0045] FIG5 illustrates a schematic diagram of an exemplary partitioning of a resource block set (RB set) in sidelink communication according to some embodiments of the present disclosure.

[0046] FIG6A illustrates a schematic flowchart of a sidelink communication method performed by a first node according to some embodiments of the present disclosure.

[0047] FIG6B illustrates a schematic diagram of exemplary signaling interactions between a first node and a second node in sidelink communication according to some embodiments of the present disclosure.

[0048] FIG7A illustrates a schematic flowchart of a sidelink communication method performed by a first node according to some embodiments of the present disclosure.

[0049] FIG7B illustrates a schematic diagram of a bitmap of a MAC CE according to some embodiments of the present disclosure.

[0050] 7C illustrates a schematic diagram of exemplary signaling interactions between a first node and a second node in sidelink communication according to some embodiments of the present disclosure.

[0051] FIG8 illustrates a schematic flow chart of a method for a first node in sidelink communication according to some embodiments of the present disclosure.

[0052] FIG9 illustrates a schematic flowchart of a sidelink communication method according to some embodiments of the present disclosure.

[0053] FIG10 illustrates a schematic flowchart of a sidelink communication method according to some embodiments of the present disclosure.

[0054] FIG11 illustrates a schematic flowchart of a sidelink communication method according to some embodiments of the present disclosure.

[0055] FIG12 illustrates a schematic flowchart of a sidelink communication method according to some embodiments of the present disclosure.

[0056] 13 illustrates a block diagram of an example system for wireless communications in accordance with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0057] The embodiments of the present disclosure describe technical matters, structural features, objectives and effects in detail with reference to the accompanying drawings, as described below. Specifically, the terms in the embodiments of the present disclosure are only used to describe the purpose of specific embodiments, rather than to limit the present disclosure.

[0058] In this disclosure, "A or B" may mean "only A," "only B," or "both A and B."

[0059] In other words, in the present disclosure, "A or B" may be interpreted as "A and / or B." For example, in the present disclosure, "A, B or C" may mean "only A," "only B," "only C," or "any combination of A, B, and C."

[0060] As used in this disclosure, a slash ( / ) or a comma may mean "and / or". For example, "A / B" may mean "A and / or B". Thus, "A / B" may mean "only A", "only B", or "both A and B". For example, "A, B, C" may mean "A, B, or C".

[0061] In the present disclosure, “at least one of A and B” may mean “only A”, “only B”, or “both A and B”. In addition, in the present disclosure, the expression “at least one of A or B” or “at least one of A and / or B” may be interpreted as “at least one of A and B”.

[0062] In addition, in the present disclosure, “at least one of A, B, and C” may mean “only A,” “only B,” “only C,” or “any combination of A, B, and C.” In addition, “at least one of A, B, or C” or “at least one of A, B, and / or C” may mean “at least one of A, B, and C.”

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the described features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0064] Those skilled in the art will recognize and appreciate that the details of the described examples are merely illustrative of some embodiments and that the teachings set forth herein are applicable to various alternative arrangements.

[0065] Figure 1 illustrates a schematic diagram of an exemplary cellular network according to some embodiments of the present disclosure. As shown in the figure, a schematic diagram of three base stations (e.g., eNBs or gNBs depending on the specific cellular standard and terminology) forming a cellular network is exemplarily depicted. Typically, base stations will be deployed by a cellular network operator to provide geographic coverage for UEs in that area. The base stations form a radio access network (RAN). The base stations provide wireless coverage for UEs in the area or cell where they are located. The base stations are interconnected via the X2 interface and connected to the core network via the S1 interface. It should be understood that only basic details are shown for the purpose of illustrating the key features of the cellular network. The Uu interface is provided between the UE and the base station for communication between the UE and the base station. The PC5 interface is provided between the UE for side link communication. The interface and component names related to Figure 1 are used as examples only, and different systems operating according to the same principles may use different nomenclature.

[0066] A base station contains the hardware and software for implementing RAN functions, facilitating communications between the base station and the core network or other base stations, control and data signaling between the core network and UEs, and wireless communications between the base station and its associated UEs. The core network includes the hardware and software for implementing network functions, such as overall network management and control, and call and data routing.

[0067] In vehicle-to-vehicle (V2V) applications, onboard UEs can be integrated into vehicles such as cars, trucks, and buses. These onboard UEs can communicate with each other in both in-coverage and out-of-coverage modes. In-coverage mode means the base station can manage and allocate resources to UEs within the base station's coverage area, while out-of-coverage mode does not require any base station management or resource allocation. In vehicle-to-everything (V2X) applications, vehicles can communicate not only with other vehicles but also with infrastructure, pedestrian devices, cellular networks, and potentially other surrounding devices.

[0068] Examples of V2X applications include the following use cases: vehicle platooning, expanded sensors, advanced driving, remote driving, high data rate communications, high reliability and low latency communications, etc.

[0069] In addition to uplink / downlink communication between UEs and base stations, sidelink communication, where UEs communicate directly with each other, is also possible. Figure 2 illustrates base stations forming a RAN, along with a transmitter (Tx) UE 150 and a receiver (Rx) UE 152 within the RAN. Base station 102 is configured to wirelessly communicate with either Tx UE 150 or Rx UE 152 via respective connections 154. Tx UE 150 and Rx UE 152 are configured to wirelessly communicate with each other via sidelink 156.

[0070] Resource pools for transmission resources are used to manage resource allocation and interference between potentially concurrent transmissions. A resource pool is a set of time-frequency resources from which transmission resources can be selected. A UE can be configured with multiple transmit and receive resource pools.

[0071] Two operating modes are used for resource allocation for sidelink communications, depending on whether the UE is within the coverage of the cellular network. In Mode 1, V2X communications operate within the coverage of a base station (e.g., eNB or gNB). All scheduling and resource allocation can be performed by the base station.

[0072] Mode 2 is applicable when the sidelink service operates outside the coverage area of ​​the cellular base station, in which case the UE needs to schedule resources on its own. To ensure fair utilization, the UE typically uses a sensed-based transmission resource allocation. Selecting resources involves two steps. In step 1, the UE identifies resources that are considered candidates, and in step 2, the specific resources are selected for transmission. Step 1 can start with a set of all resources in the selection window and then remove those resources that are not considered candidates (for example, resources reserved by another UE with a SL RSRP above a threshold). The resource selection step may be random and may have constraints such as HARQ timing and delay between resources. In Mode 2, the UE selects the transmission resources it wishes to use for transmission and transmits a Sidelink Control Information (SCI) message to indicate these resources. The recipient of the SCI message (which can be a single UE in unicast, a group of UEs in multicast, or all accessible UEs in broadcast) can obtain the details of the transmission to be expected through the SCI. The SCI message is the control information required to decode the sidelink data content and also indicates the reserved resources. In the first phase, the SCI message is transmitted on the Physical Sidelink Control Channel (PSCCH), and in the second phase, it is transmitted on the Physical Sidelink Shared Channel (PSSCH). The UE can reserve transmission resources for the transport block (TB) used for the initial transmission of data, or for repeated transmissions of TBs to improve reliability in the event of an initial transmission failure.

[0073] Configuration of primary and secondary carriers for sidelink carrier aggregation

[0074] Sidelink communication has received extensive attention within 3GPP (3rd Generation Partnership Project), particularly in 5G technology. It is considered a key capability that will enable many new application scenarios, such as connected vehicles, the Internet of Things, and public safety communications.

[0075] User equipment (UE) (UE) can communicate directly with other nearby devices through sidelink communication, eliminating the need for base station relay. This direct communication offers the advantages of low latency and high reliability, while also reducing pressure on base stations and network congestion. Sidelink communication enables user equipment (UE) to conduct fast and reliable point-to-point or multicast communications while meeting specific quality of service (QoS) requirements.

[0076] 3GPP standardizes various technologies and protocols for sidelink communications to support different application scenarios and requirements. These standards include specifications for resource allocation, scheduling, power control, link management, and security to ensure the smooth operation of sidelink communications in mobile communication systems.

[0077] Cross-carrier scheduling is not supported in sidelink communications in 3GPP Rel_18 and earlier versions. While Rel_18 introduced the concept of carrier aggregation (CA), due to time constraints, it was explicitly stated that cross-carrier scheduling would not be implemented in Rel_18. However, as the standard evolves, cross-carrier scheduling is likely to be introduced in sidelink communications in Rel_19, expected to begin in 2024. Cross-carrier scheduling presents a number of challenges that need to be addressed, which are reflected and addressed in this article.

[0078] The Work Item Description (WID) of the Rel_18 version clearly states that no distinction is made between primary carriers and secondary carriers in terms of carrier aggregation (CA).

[0079] In related technologies, when conventional UE and base station communication is performed over the Uu interface, the configuration of the PCell associated with the primary carrier is typically placed in the CellGroupConfig, while the configuration of the SCell associated with the secondary carrier is placed in the sCellToAddModList in the CellGroupConfig. Therefore, it is possible to specify and distinguish between the primary carrier and the secondary carrier in carrier aggregation. However, as mentioned above, in the sidelink technology of Rel_18, there is no distinction between the primary carrier and the secondary carrier. Therefore, it is not possible to configure the secondary carrier by specifying the primary carrier (e.g., configuring the RRC configuration of the secondary carrier), as in carrier aggregation under the Uu interface.

[0080] Furthermore, in related technologies, the PDCP (Packet Data Convergence Protocol) configuration typically includes a primary path. In this configuration, the primary path can be specified using a logical channel. This is because, under the PDCP retransmission mechanism, the two RLC (Radio Link Control) entities must reside on two carriers. Therefore, specifying a carrier is equivalent to specifying the primary path.

[0081] However, in sidelink communications, there is generally no concept of cell groups. The introduction of cell groups can be used to describe the association relationship and configuration information between UEs and base stations in mainlink communications. In sidelink communications, the main focus is on the setup and management of the sidelink, and does not involve the cell group configuration in mainlink communications. Therefore, in the sidelink, a node (e.g., the first node (such as a Tx UE)) cannot specify the primary path through the logical channel ID of a cell group, and therefore cannot specify the primary carrier in carrier aggregation.

[0082] In view of the above problems and research on related technologies, in sidelink communication, when it is necessary to perform carrier aggregation on licensed carriers and unlicensed carriers, based on the characteristics of each carrier, it is necessary to distinguish between the main carrier and the secondary carrier in the carrier aggregation to improve the efficiency and reliability of sidelink communication.

[0083] Figure 3A illustrates a schematic flow chart of a sidelink communication method according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, a sidelink communication method is provided, comprising: operation 310: sending a carrier aggregation indicator, wherein the carrier aggregation indicator is used to indicate a primary carrier and a secondary carrier in sidelink carrier aggregation; and operation 312: receiving a message indicating that configuration of the primary carrier and the secondary carrier is complete, wherein the message indicating that configuration of the primary carrier and the secondary carrier is complete is returned by a node that receives the carrier aggregation indicator.

[0084] Specifically, according to some embodiments of the present disclosure, the method may be performed by a first node and include: the first node in sidelink communication sending a carrier aggregation indicator to a second node in sidelink communication, wherein the carrier aggregation indicator is used to indicate the primary carrier and secondary carrier in sidelink carrier aggregation; and the first node receiving a message from the second node indicating that the configuration of the primary carrier and the secondary carrier is complete, wherein the message indicating that the configuration of the primary carrier and the secondary carrier is complete is returned by the second node that received the carrier aggregation indicator. Thus, during carrier aggregation CA, the relevant nodes can distinguish between the primary and secondary carriers, thereby improving the efficiency and reliability of sidelink communication.

[0085] According to some embodiments of the present disclosure, sending the carrier aggregation indicator includes: sending a sidelink reconfiguration message, wherein the sidelink reconfiguration message includes the carrier aggregation indicator. The sidelink reconfiguration message is, for example, an RRCReconfigurationSidelink message.

[0086] According to some embodiments of the present disclosure, the sending of the carrier aggregation indicator includes: sending a sidelink system information block message, the sidelink information block message including the carrier aggregation indicator.

[0087] It should be understood that the carrier aggregation indicator may also be included in other types of messages and sent by the first node to the second node, which also does not depart from the scope of the present disclosure.

[0088] Figure 3B illustrates a schematic diagram of an exemplary signaling interaction between a first node and a second node in a sidelink communication according to some embodiments of the present disclosure. Specifically, according to some embodiments of the present disclosure, the method can be performed by a first node and includes: the first node in the sidelink communication configures the sidelink reconfiguration message to have a carrier aggregation indicator, wherein the carrier aggregation indicator is used to indicate the primary carrier in the sidelink carrier aggregation SL CA; the first node transmits the sidelink reconfiguration message to the second node in the sidelink communication; and the first node receives a sidelink reconfiguration completion message from the second node, wherein the second node receives the sidelink reconfiguration message and sends a sidelink reconfiguration completion message after completing the configuration according to the sidelink reconfiguration message. Thus, through the above process, the primary carrier in the sidelink carrier aggregation can be specified by configuring the carrier aggregation indicator in the sidelink reconfiguration message by a node in the sidelink communication (e.g., the first node). This enables the sidelink to effectively perform carrier aggregation and achieve better performance and resource utilization during the communication process. At the same time, the message transmission between the first node and the second node ensures the correct configuration and operation completion of the sidelink.

[0089] In some examples, when the index of a candidate sidelink carrier is included in the sidelink reconfiguration message, the size of the carrier aggregation indicator can be a single bit to indicate whether the candidate sidelink carrier can serve as the primary carrier in the sidelink carrier aggregation SL CA.

[0090] In some examples, when the indexes of multiple candidate side link carriers are included in the side link reconfiguration message, the carrier aggregation indicator can be in the form of a string of bits (e.g., one octet) or a bitmap, depending on the number of candidate side link carriers, to indicate which carrier among the multiple candidate side link carriers is used as the primary carrier in SL CA.

[0091] It can be understood that the above examples are provided for illustrative purposes only, and the present disclosure does not impose any limitation on the form of the carrier aggregation indicator.

[0092] In some examples, the sidelink reconfiguration message can be an RRC sidelink reconfiguration message (RRCReconfigurationSidelink). Accordingly, the sidelink reconfiguration completion message can be an RRC sidelink reconfiguration completion message (RRCReconfigurationCompleteSidelink). Of course, the sidelink reconfiguration message can also take any other suitable form, including but not limited to, a MAC reconfiguration message, an RLC reconfiguration message, a PDCP reconfiguration message, a PHY reconfiguration message, an SDAP (Service Data Adaptation Protocol) reconfiguration message, and the like. Accordingly, the sidelink reconfiguration completion message can also take a corresponding form. The above-mentioned various types of reconfiguration messages are used for configuration and adjustment between different layers and protocols in sidelink communication to ensure the correct operation and performance optimization of the sidelink.

[0093] To enable a Tx UE in sidelink communication to distinguish between two carriers, the sidelink reconfiguration message (e.g., RRCReconfigurationSidelink) exchanged between the nodes needs to include carrier configuration information, such as a carrier index and frequency configuration. According to some embodiments of the present disclosure, the carrier aggregation indicator includes at least one of a cell ID or a carrier index.

[0094] According to some embodiments of the present disclosure, the sidelink carrier aggregation includes carrier aggregation of a licensed carrier with another licensed carrier, carrier aggregation of a licensed carrier with an unlicensed carrier, or carrier aggregation of an unlicensed carrier with another unlicensed carrier. Specifically, according to some embodiments of the present disclosure, SL CA includes but is not limited to carrier aggregation of a licensed carrier with another licensed carrier, carrier aggregation of a licensed carrier with an unlicensed carrier, or carrier aggregation of an unlicensed carrier with another unlicensed carrier, etc.

[0095] As mentioned above, in Rel-18 sidelink technology, there is no distinction between primary and secondary carriers. Therefore, in RRC configuration, secondary carriers are not configured through the primary carrier, as is done with carrier aggregation over the Uu interface. Consequently, a node (e.g., the first node (e.g., a Tx UE)) cannot configure a primary RLC entity to send PDCP control protocol data units (PDUs) over the air interface of sidelink communications, as is done with the Uu interface.

[0096] According to some embodiments of the present disclosure, the primary carrier can be used to transmit the control protocol data unit (PDU) of the packet data convergence protocol (PDCP). Thus, the designated primary carrier can be used to carry the transmission of PDCP control information, thereby improving the efficiency and reliability of data transmission in sidelink communication.

[0097] Through the above embodiments, the present disclosure solves the technical problem of how to perform carrier aggregation in side link communications, facilitates carrier aggregation between multiple carriers, and improves the overall transmission capacity and bandwidth utilization of side link communications.

[0098] Increased latency requirements for sidelink communications

[0099] Sidelink communications have strict latency requirements in V2X services. Excessive latency can result in vehicles receiving sidelink data only after, for example, a traffic accident has occurred. This is unacceptable and must be avoided.

[0100] In related technologies, URLLC (Ultra-reliable and Low Latency Communication) services based on the Uu interface require the use of licensed spectrum. However, as mentioned above, virtually all services on the sidelink have strict low latency requirements. Carrier aggregation on the sidelink enables the aggregation of licensed and unlicensed carriers, so unlicensed carriers on the sidelink also have a strong need to achieve low latency.

[0101] Based on research on related technologies, it has been found that when a UE cannot obtain available transmission resources through the Listen-Before-Talk (LBT) mechanism on the sidelink, it will report an LBT failure. If LBT failures occur multiple times, resource reselection may occur. However, this process is time-consuming.

[0102] According to some embodiments of the present disclosure, a sidelink communication method is provided that can be used to control a first node in a sidelink to perform reselection. The method can be performed by the first node and includes: the first node in the sidelink communication is triggered to perform the reselection in response to a trigger condition being satisfied.

[0103] The above method can bring the following technical benefits.

[0104] Reduced latency: Triggering the first node to reselect reduces the time wasted during the reselection process. Once the triggering conditions are met, the first node can be reselected as quickly as possible, thus reducing communication latency.

[0105] Improved efficiency: By quickly triggering the first node to perform reselection, unnecessary resource waste can be minimized. This will improve the efficiency of sidelink communication and ensure that resources are fully utilized when necessary.

[0106] Enhanced reliability: Prompt reselection after trigger conditions are met improves the reliability of sidelink communications. By reducing the time required for reselection, the risk of packet loss and communication interruptions is reduced, thereby enhancing the reliability of the overall system (such as an autonomous driving system using V2X communication).

[0107] As a result, the first node can quickly perform reselection in response to meeting the trigger condition, which can effectively shorten the time required for reselection in side link communication, improve communication efficiency, reduce delays, and enhance communication reliability.

[0108] FIG3C illustrates a schematic flow chart of a resource reselection method in sidelink communication according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, a resource reselection method in sidelink communication is provided, comprising: operation 330: configuring one or more first listen-before-send (LBT) failure counters under carrier aggregation (CA), wherein the first LBT failure counters are configured to record the number of LBT failures occurring under the CA, and the first LBT failure counters correspond to a first threshold; operation 332: configuring a second LBT failure counter under non-CA, wherein the second LBT failure counters are configured to record the number of LBT failures occurring under the non-CA, wherein the second LBT failure counters correspond to a second threshold, and the first threshold is greater than the second threshold; and operation 334: performing resource reselection when the value of the first LBT failure counter reaches the first threshold.

[0109] By performing resource reselection when the value of the first LBT failure counter reaches the first threshold, more LBT failures can be tolerated, thereby reducing the number of resource reselections and achieving the purpose of reducing delay.

[0110] According to some embodiments of the present disclosure, this technical solution is applicable to the case where two carriers are used. According to some embodiments of the present disclosure, this technical solution is applicable to the case where the carrier aggregation indicator indicates the primary / secondary carrier. Specifically, the present disclosure provides the following exemplary options.

[0111] ●Option 1: Configure a separate set of LBT counters and timers in the SL CA scenario.

[0112] According to some embodiments of the present disclosure, a timer is used to cooperate with a dedicated counter, for example, to configure a separate set of LBT counters and timers in a SL CA scenario.

[0113] According to some embodiments of the present disclosure, the one or more first LBT failure counters are configured to respectively record the number of LBT failures occurring on multiple carriers under the CA; when the value of the first LBT failure counter reaches the first threshold, performing the resource reselection includes: when the value of the first LBT failure counter corresponding to any carrier among the multiple carriers reaches the first threshold, performing the resource reselection for the any carrier.

[0114] In the relevant technology / protocol, in the non-carrier aggregation scenario, there is a counter LB_COUNT for counting LBT failures and a count upper limit lbt-FailureInstanceMaxCount for the counter. When the number of LBT failure indications reported via the physical layer L1 (for example, reported by a node (for example, a first node (such as Tx UE)) reaches the count upper limit, a continuous LBT failure (C-LBT failure) will be triggered. In addition, there is a timer lbt-FailureDetectionTimer in the relevant technology / protocol. When the timer expires, the node (for example, the first node) restarts the counter LB_COUNT.

[0115] In view of this, in a carrier aggregation scenario, if one carrier experiences an LBT failure while another carrier does not, it can be assumed that the node in the sidelink communication (e.g., Tx UE) can still send data normally. Therefore, for sidelink communication, more LBT failure indications from the carrier(s) experiencing LBT failures can be tolerated.

[0116] Thus, illustratively, the present disclosure introduces a count upper limit for determining C-LBT failure in a carrier aggregation scenario (e.g., in sidelink communication), namely, a first LBT failure counter CA_lbt-FailureInstanceMaxCount, which is used to distinguish it from a second LBT failure counter lbt-FailureInstanceMaxCount. Generally speaking, CA_lbt-FailureInstanceMaxCount is larger than lbt-FailureInstanceMaxCount.

[0117] For example, the present disclosure also introduces a new timer for determining C-LBT failure in carrier aggregation scenarios (e.g., in sidelink communications), namely CA_lbt-FailureDetectionTimer, to distinguish it from lbt-FailureDetectionTimer. Generally speaking, CA_lbt-FailureDetectionTimer has a smaller value than lbt-FailureDetectionTimer, mainly considering the need for low latency for essentially all services in sidelink communications, for example.

[0118] According to some embodiments of the present disclosure, the trigger condition includes a value of a first counter exceeding a first threshold.

[0119] According to some embodiments of the present disclosure, the first counter is configured to count the number of listen-before-talk (LBT) failures occurring on any component carrier under carrier aggregation in the sidelink communication, where the component carrier includes a licensed carrier and / or an unlicensed carrier.

[0120] According to some embodiments of the present disclosure, the first node being triggered to perform the reselection in response to a trigger condition being satisfied may include: triggering the first node to perform the resource reselection when the value of the first counter exceeds the first threshold.

[0121] According to some embodiments of the present disclosure, the first threshold is set to be greater than the maximum allowed number of LBT failures that occur on any of the component carriers in the absence of the carrier aggregation. Thus, by setting the threshold of the first counter, resource reselection can be triggered based on the carrier aggregation situation of the sidelink communication, which can more accurately determine when to trigger the reselection process, thereby improving efficiency. In addition, this setting provides flexibility, making the triggering conditions closer to the carrier aggregation scenario and ensuring that resource reselection is triggered under appropriate circumstances.

[0122] According to some embodiments of the present disclosure, the first timer is configured to be started since the most recent LBT failure occurring on the component carrier.

[0123] According to some other embodiments of the present disclosure, the first counter is configured to reset when the value of the first timer exceeds a second threshold. The second threshold can be set to be smaller than the expiration time of the first timer in the absence of carrier aggregation. Thus, the first timer is started based on the time of the most recent LBT failure, ensuring that resource reselection is triggered at the correct time. Furthermore, the first counter can be reset based on a second threshold, which is set to be smaller than the expiration time of the first timer in the absence of carrier aggregation. This reset logic optimization can further optimize the process of triggering and executing resource reselection.

[0124] ● Option 2: Configure a combined LBT counter for all unlicensed carriers in the SL CA scenario.

[0125] According to some embodiments of the present disclosure, the timer is used to cooperate with a dedicated counter, for example, to configure a combined LBT counter for all unlicensed carriers in a SL CA scenario.

[0126] According to some embodiments of the present disclosure, the one or more first LBT failure counters are configured to record the combined number of LBT failures occurring on multiple carriers under the CA; when the value of the first LBT failure counter reaches the first threshold, performing the resource reselection includes: when the value of the first LBT failure counter reaches the first threshold, performing the resource reselection on the carrier with a larger number of LBT failures among the multiple carriers.

[0127] The first LBT failure counter is, for example, a combined LBT counter configured for all unlicensed carriers in the SL CA scenario.

[0128] Through the first LBT failure counter, when the value of the first LBT failure counter reaches the first threshold, resource reselection is performed on the corresponding carrier with a larger number of failures.

[0129] In related technologies, in non-carrier aggregation scenarios, each carrier is configured with an independent counter and a unified upper limit (lbt-FailureInstanceMaxCount) for counting its LBT failures. When the number of LBT failure indications for a carrier reported via the physical layer L1 (e.g., by a node (e.g., the first node (e.g., Tx UE)) reaches this upper limit, a (continuous) LBT failure is triggered for that carrier.

[0130] In sidelink communications, given the low latency requirements of services, when SL CA involves multiple unlicensed carriers, each unlicensed carrier needs to comprehensively consider the LBT failures that occur on each unlicensed carrier (e.g., the number of LBT failures reported by each). For example, assume that the upper limit of the LB_COUNT count of the unlicensed carrier SL-U carrier1 in SL CA is configured to be 10, and SL-U carrier1 has experienced 6 LBT failures (e.g., 6 LBT failure indications have been reported). If SL-U carrier2 has not experienced an LBT failure, then SL-U carrier1 can wait until the LB_COUNT count reaches 10 (e.g., 10 LBT failure indications have been reported) before performing, for example, resource reselection. However, if SL-U carrier 2 has also experienced four LBT failures at the same time as SL-U carrier 1 has experienced six LBT failures (for example, four LBT failure indications have been reported via the L1 layer), then SL-U carrier 2 will likely trigger an LBT failure soon. Therefore, it is necessary for SL-U carrier 1 to trigger an LBT failure in advance to avoid concurrently triggering (continuous) LBT failures and performing, for example, resource reselection at the same or similar times as SL-U carrier 2. That is, if SL-U carrier 1 has experienced six LBT failures and SL-U carrier 2 has also experienced four LBT failures, SL-U carrier 1 triggers (continuous) LBT failures to trigger the first node to perform, for example, resource reselection, even if its LB_COUNT count is still four times short of the upper limit of 10.

[0131] It is understandable that there may be situations where more than two unlicensed carriers participate in SL CA. In such scenarios, it is also necessary to comprehensively consider the situations where LBT failures occur in all unlicensed carriers (for example, the number of LBT failures reported by each), so as to avoid multiple unlicensed carriers triggering their own (continuous) LBT failures at the same or similar time and thus concentrating on performing, for example, resource reselection, which causes a sharp decline in the quality of side link communications or even leads to the interruption of side link communications.

[0132] According to some embodiments of the present disclosure, the trigger condition is that the value of the second counter exceeds a third threshold.

[0133] According to some embodiments of the present disclosure, the second counter is configured to combine and count the number of listen-before-talk (LBT) failures occurring on several unlicensed carriers under carrier aggregation in the sidelink communication.

[0134] According to some embodiments of the present disclosure, the first node being triggered to perform the reselection in response to the trigger condition being met may include: when the value of the second counter exceeds the third threshold, triggering the first node to perform the resource reselection for one or more of the unlicensed carriers in which the LBT failures have occurred a large number of times.

[0135] As an example and not a limitation, assuming that SL CA involves three unlicensed carriers SL-U carrier4, SL-U carrier5, and SL-U carrier6, a combined LBT counter can be configured for these three unlicensed carriers, and the upper limit of the count for the combined counter can be set to 20 times. At a certain moment, when the carriers SL-U carrier4 and SL-U carrier5 have respectively reported 9 and 8 LBT failure indications through the L1 layer, and SL-U carrier6 has also reported 3 LBT failure indications, then at this time, the first node in the sidelink communication can be triggered to perform resource reselection for the two unlicensed carriers SL-U carrier4 and SL-U carrier5, because the cumulative number of LBT failures of the three unlicensed carriers has reached the upper limit of the combined counter, and the number of LBT failures of the two unlicensed carriers SL-U carrier4 and SL-U carrier5 is large and similar.

[0136] Thus, by setting the threshold of the second counter, resource reselection can be triggered based on the carrier aggregation situation of the sidelink communication. This can more accurately determine when to trigger the reselection process, thereby improving efficiency. In addition, this setting provides flexibility, making the triggering conditions more closely aligned with the carrier aggregation scenario and ensuring that the node in the sidelink communication (e.g., the first node) is triggered to perform resource reselection when appropriate.

[0137] ● Option 3: In the SL CA scenario, if licensed carriers and unlicensed carriers are aggregated, a dedicated LBT counter is configured for the unlicensed carrier and an upper limit of the counter is set.

[0138] Considering the scenario where the primary carrier in SL CA is a licensed carrier, the licensed carrier is not at risk of LBT failure, and therefore has higher resource availability than unlicensed carriers. Therefore, in the SL CA scenario, if licensed and unlicensed carriers are aggregated, a more redundant upper limit can be set for the LBT counter dedicated to the unlicensed carrier, compared to the lbt-FailureInstanceMaxCount in the related art.

[0139] According to some embodiments of the present disclosure, the first LBT failure counter is configured to record the number of LBT failures occurring on the unlicensed carrier under the CA; when the value of the first LBT failure counter reaches the first threshold, performing the resource reselection includes: when the value of the first LBT failure counter reaches the first threshold, performing the resource reselection for the unlicensed carrier.

[0140] By using a first LBT failure counter, when the value of the first LBT failure counter reaches the first threshold, the resource reselection is performed for the unlicensed carrier.

[0141] According to some embodiments of the present disclosure, the trigger condition is that the value of the third counter exceeds a fourth threshold.

[0142] According to some embodiments of the present disclosure, the third counter is configured to count the number of listen-before-talk (LBT) failures that occur on an unlicensed carrier under carrier aggregation in the side link communication, wherein the carrier aggregation is carrier aggregation between a licensed carrier and the unlicensed carrier.

[0143] According to some embodiments of the present disclosure, the first node being triggered to perform the reselection in response to a trigger condition being satisfied may include: triggering the first node to perform the resource reselection for the unlicensed carrier if the value of the third counter exceeds the fourth threshold.

[0144] According to some embodiments of the present disclosure, the fourth threshold is set to be greater than the maximum allowed value of the number of LBT failures occurring on either the licensed carrier or the unlicensed carrier in the absence of the carrier aggregation. Thus, by setting the threshold of the third counter, a node in the sidelink communication (e.g., the first node) can be triggered to perform resource reselection based on the carrier aggregation situation of the sidelink communication, which can more accurately determine when to trigger the reselection process, thereby improving efficiency. In addition, this setting can provide flexibility, making the triggering conditions closer to the carrier aggregation scenario and ensuring that resource reselection is triggered under appropriate circumstances.

[0145] According to some embodiments of the present disclosure, the second timer is configured to be started from the last LBT failure occurring on the unlicensed carrier.

[0146] According to some embodiments of the present disclosure, the third counter is further configured to be reset when the value of the second timer exceeds a fifth threshold, and the fifth threshold is set to be less than the expiration time of the second timer in the absence of the carrier aggregation. Thus, the second timer is started according to the time when the LBT failure on the unlicensed carrier last occurred, ensuring that the execution of resource reselection is triggered at the correct time point. In addition, the third counter can also be reset according to the fifth threshold, and the fifth threshold is set to be less than the expiration time of the second timer in the absence of carrier aggregation. This reset logic optimization can further optimize the process of triggering and executing resource reselection. The optimized reset logic described herein is embodied in that the timer is reset based on the expiration of the timer, and the expiration time of the timer can be set to be smaller than the expiration time in a scenario without carrier aggregation (for example, only using the licensed carrier for side link data transmission), thereby adapting to the low latency requirements of the side link communication.

[0147] According to some embodiments of the present disclosure, the reselection includes carrier reselection.

[0148] As used herein, resource reselection and carrier reselection are two important steps in wireless communication. They are two independent processes, but their order may vary depending on specific circumstances.

[0149] Carrier reselection is the process of selecting the optimal carrier frequency or channel in wireless communications. This is done to optimize communication quality and avoid interference. In wireless networks, devices periodically monitor and select the optimal carrier frequency based on predefined metrics such as signal strength, quality, and interference levels.

[0150] Resource reselection involves selecting the optimal time and / or frequency domain resources in wireless communications, such as time slots, subcarriers, and code rates. This is done to optimize wireless resource utilization and improve data transmission efficiency. In wireless networks, devices select appropriate resource allocation based on network conditions and communication requirements.

[0151] In some wireless communication protocols, such as LTE (Long Term Evolution), carrier reselection is typically performed before resource reselection. This is because selecting the optimal carrier frequency is crucial for establishing a reliable physical connection, while resource reselection can better adapt to the network environment and data transmission requirements.

[0152] However, in some cases, especially in different wireless communication protocols or systems, the order may be different. Therefore, the order of carrier reselection and resource reselection needs to be determined according to the specific situation to ensure communication quality and resource utilization efficiency, and this disclosure does not impose any restrictions on this.

[0153] Option 4: Define carrier reselection conditions in SL scenarios

[0154] Figure 3D illustrates a schematic flow chart of a carrier reselection method for sidelink communication according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, a carrier reselection method for sidelink communication is provided, comprising: operation 340: receiving a listen-before-send LBT failure message regarding a target carrier; operation 342: performing carrier reselection for the target carrier in response to the LBT failure message matching a preset condition; wherein the preset condition includes: a first occurrence of an LBT failure on the target carrier; or consecutive occurrences of LBT failures on the target carrier.

[0155] By performing carrier reselection on the target carrier in response to matching the preset conditions in the LBT failure message, carrier reselection can be quickly performed on the carrier where the problem occurs, thereby reducing the possibility of subsequent problems and achieving the purpose of reducing delay.

[0156] Continuous LBT failures, for example, refer to multiple consecutive LBT failures of the UE on one carrier within a (eg, short) time range. The time range and number threshold can be determined based on actual conditions and are not limited in this disclosure.

[0157] In related art, there may be two rounds of selection for a carrier. For example, for a carrier, sensing is performed first to perform the first round of resource selection. If the sensing result does not meet the requirements, such as the PDB (Packet Delay Budget), resource reselection is performed. The second round of resource selection involves LBT. If an LBT failure occurs on a carrier, the node in the sidelink communication sends an LBT failure indication to the L2 layer (data link layer) on the L1 layer. When the lbt-FailureInstanceMaxCount is reached, it is considered that there are continuous LBT failures, and resource reselection is required.

[0158] In LTE LTE, carrier reselection is related to the Channel Busy Rate (CBR) (for example, the per-carrier-per-priority CBR threshold for carrier selection (reselection) and the per-carrier-per-priority CBR threshold for carrier holding). However, in 5G NR, there is no such concept.

[0159] Therefore, with the evolution of standards and research on related technologies, the present disclosure provides conditions for carrier reselection in the scenario of sidelink communication.

[0160] Condition 1: When LBT fails on a carrier, direct carrier reselection is performed. This is mainly because if an LBT failure occurs, there is a possibility of long-term conflict between the carrier and Wi-Fi, so direct carrier reselection is considered.

[0161] According to some embodiments of the present disclosure, the trigger condition includes a listen-before-talk (LBT) failure occurring on a first carrier, and the first node transmitting data on the first carrier.

[0162] According to some embodiments of the present disclosure, the first node being triggered to perform the reselection in response to a trigger condition being satisfied may include: if the LBT failure occurs on the first carrier, the first node performing the carrier reselection for the first carrier. This avoids the risk of long-term conflict between sidelink communication and wireless broadband communication on the carrier, thereby improving the efficiency and reliability of sidelink communication.

[0163] Condition 2: Carrier reselection is performed when consecutive LBT failures occur on a carrier. This approach does not require modification of the LBT failure process. If a UE experiences multiple consecutive LBT failures on a carrier within a (for example, short) timeframe, the UE considers the possibility of a long-term conflict between the carrier and Wi-Fi and considers direct carrier reselection.

[0164] According to some embodiments of the present disclosure, the trigger condition may include: within a preset time period, a listen-before-talk (LBT) failure occurs on the first carrier for a preset number of times, and the first node transmits data on the first carrier.

[0165] According to some embodiments of the present disclosure, the first node being triggered to perform the reselection in response to satisfaction of a trigger condition may include: triggering the first node to perform the carrier reselection for the first carrier if the LBT failure occurs on the first carrier for the preset number of times within the preset time period. Through the above embodiments, the present disclosure solves the technical problem of how to perform reselection in the sidelink, facilitates the rational scheduling and optimization of transmission resources in sidelink communications, and improves the efficiency and reliability of sidelink communications.

[0166] Cross-carrier configuration of PSFCH resources

[0167] According to the PSFCH (Physical Sidelink Feedback Channel) feedback mechanism in the related art, PSFCH resources are specified by RRC (Radio Resource Control) and Tx UE in SCI 1A (i.e., Sidelink Control Information 1A). The resource blocks (RBs) used by each PSFCH can correspond to the RBs used by the PSSCH (Physical Sidelink Sharing Channel). However, if the PSSCH is successfully transmitted, but the PSFCH cannot be transmitted due to LBT failure, the transmission of the PSFCH will fail.

[0168] FIG4A illustrates a schematic flow chart of a sidelink communication method performed by a first node according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, a sidelink communication method is provided, performed by a first node, comprising: Operation 410: configuring sidelink control information SCI signaling by the first node in the sidelink communication, the SCI signaling indicating resources for transmitting a physical sidelink feedback channel PSFCH by a second node in the sidelink communication, wherein the resources of the PSFCH are transmitted by the second node based on a physical sidelink shared channel PSSCH transmitted by the first node; wherein the resources used for the PSFCH are different from the resources used for the PSSCH.

[0169] According to some embodiments of the present disclosure, the present technical solution can be implemented independently. According to some embodiments of the present disclosure, the present technical solution can be implemented independently in a scenario with two available carriers.

[0170] This technical solution ensures that after PSSCH is successfully sent, PSFCH will not fail to be sent due to LBT failure.

[0171] In order to solve the above problems, the present disclosure provides the following options.

[0172] Option 1: All resources used to transmit the PSFCH can be scheduled on another carrier, such as the granted carrier.

[0173] FIG4B illustrates a schematic diagram of an exemplary signaling interaction between a first node and a second node in sidelink communication according to some embodiments of the present disclosure. As shown, the first node in sidelink communication transmits a PSSCH to the second node. In response to receiving the PSSCH, the second node transmits a PSFCH to the first node.

[0174] According to some embodiments of the present disclosure, a sidelink communication method is provided that can be used for transmission resource configuration of sidelink communication. The method can be performed by a first node and includes: configuring sidelink control information (SCI) signaling by the first node in the sidelink communication, the SCI signaling indicating resources for transmitting a physical sidelink feedback channel (PSFCH) by a second node in the sidelink communication, wherein the PSFCH is transmitted by the second node based on a physical sidelink shared channel (PSSCH) transmitted by the first node.

[0175] According to some embodiments of the present disclosure, the SCI signaling is transmitted on a first carrier.

[0176] According to some embodiments of the present disclosure, the SCI signaling includes a carrier index, and the second carrier corresponding to the carrier index is scheduled by the second node to carry resources of the PSFCH.

[0177] Feedback channels are crucial in wireless communication systems for achieving efficient data transmission and resource management, including but not limited to resource allocation and scheduling optimization, adaptive modulation and coding, link adaptation, interference management and mitigation, and more. With this in mind, the aforementioned method allows all resources used to transmit the PSFCH to be placed on a carrier (e.g., a licensed carrier) that is different from the carrier used to transmit the PSSCH (and / or SCI signaling) (e.g., an unlicensed carrier), thereby improving the efficiency and reliability of sidelink communications.

[0178] Option 2: When continuous LBT failures occur on PSFCH resources, schedule PSFCH using another carrier, such as the granted carrier.

[0179] According to some embodiments of the present disclosure, when a carrier originally scheduled to carry the PSFCH experiences consecutive listen-before-talk (LBT) failures, the second node schedules the second carrier to carry the PSFCH. Thus, when consecutive LBT failures occur on the carrier originally used to transmit the PSFCH, all resources used to transmit the PSFCH can be placed on another carrier (e.g., a licensed carrier) that is different from the carrier used to transmit the PSSCH (and / or SCI signaling) (e.g., an unlicensed carrier), thereby improving the efficiency and reliability of sidelink communication.

[0180] Option 3: Scheduling PSFCH across resource block sets (RB sets)

[0181] In the Rel_18 version of the PSFCH feedback mechanism, multiple PSFCH opportunities can be configured. In other words, multiple PSFCH resources can be configured within a resource block set in a time slot. PSSCH resources and corresponding PSFCH resources can be on the same resource block set or on different resource block sets, depending on the specific protocol settings and implementation.

[0182] Based on research on related technologies, the above process can be enhanced. For example, if LBT occurs on a resource block set configured with PSFCH resources, then other resource block sets can be used to carry PSFCH resources.

[0183] A subsequent problem is that if resources of other resource block sets are used to carry PSFCH resources, the other resource block sets need to be configured to provide redundant resources, for example, by splitting themselves into multiple resource block sets.

[0184] Figure 5 illustrates a schematic diagram of an exemplary division of resource block sets in sidelink communication according to some embodiments of the present disclosure. As shown in the figure, there are at least three resource block sets on time slot 1, namely RBS1 to RBS3. It is assumed that RBS1 carries PSSCH resources. After the first node in the sidelink communication transmits the PSSCH to the second node, it is assumed that in time slot 6, the feedback for the received PSSCH, i.e., the PSFCH resources, will originally be carried in the corresponding RBS1. However, due to an LBT failure in RBS1, the PSFCH resources are now placed in a redundant resource block set in RBS2-1, RBS2-2, or RBS2-3 for scheduling, such as RBS2-2. It can be understood that RBS2-1, RBS2-2, and RBS2-3 are obtained by splitting the original resource block set RBS2. The original RBS2 may be used to carry feedback for another PSSCH carried in a resource block set on time slot 1 (e.g., RBS2 on time slot 1) (i.e., the PSFCH resources corresponding to the other PSSCH). Now, the feedback for this other PSSCH may be carried by, for example, RBS2-1 (or RBS2-3) on time slot 6.

[0185] From this, the following scheme can be summarized.

[0186] First, for each resource block set used to carry PSSCH (for example, RBS2 on time slot 1), multiple resource block sets (for example, RBS2-1, RBS2-2, and RBS2-3 on time slot 6) are configured. One resource block set (for example, RBS2-1 on time slot 6) is reserved for the PSFCH resources corresponding to the PSSCH, and other resource block sets (for example, RBS2-2 or RBS2-3 on time slot 6) are used as redundant backups for resource block sets (for example, the resource block set RBS1 on time slot 6 in the above example) that should carry PSFCH resources corresponding to other PSSCHs (for example, carried in RBS1 on time slot 1) in case of LBT failure.

[0187] Secondly, SCI 1A needs to add an indication to specify that a resource block set carrying PSFCH resources can provide redundant resources for carrying other PSFCHs for use when LBT failure occurs in other resource block sets.

[0188] Furthermore, when other resource block sets use redundant resources, the resource block set number needs to be added to indicate which resource block set occupies this redundant resource after an LBT failure occurs (for example, RBS1 on time slot 6 has an LBT failure, and thus occupies RBS2-2 on time slot 6).

[0189] Finally, before an LBT failure occurs on a resource block set, SCI 1A on the PSSCH specifies which resource block set has been configured with redundant backup for carrying other PSFCHs, or has been partitioned to include redundant backup for carrying other PSFCHs.

[0190] As a result, efficient scheduling of PSFCH across resource block sets is achieved, improving the efficiency and reliability of sidelink communications.

[0191] According to some embodiments of the present disclosure, the SCI signaling may include a resource block set RB set index, and the RB set corresponding to the RB set index may be configured as a redundant resource.

[0192] According to some embodiments of the present disclosure, the RB set index is indication information of redundant resources of the PSFCH.

[0193] According to some embodiments of the present disclosure, the SCI signaling may indicate a time slot in which the PSFCH is transmitted.

[0194] Although in the above example, the PSSCH and the corresponding PSFCH are transmitted in resource block sets with the same number on different time slots, it is understandable that the PSSCH and the corresponding PSFCH can also be transmitted in resource block sets with different numbers on different time slots. For example, the PSSCH can be transmitted in resource block set 1 on time slot 0, and the corresponding PSFCH can be transmitted in resource block set 3 on time slot 5 (of course, it can also be any other time slot except time slot 1) (of course, it can also be any other resource block set numbered not 1 or its redundant backup except resource block set 1 and its included redundant backup) and so on. This depends on the setting and implementation of the specific protocol, and the present disclosure does not impose any limitation on this.

[0195] Through the above embodiments, the present disclosure solves the technical problem of how to configure transmission resources in sidelink communications, facilitates the appropriate configuration of transmission resources for data and feedback information in sidelink communications, and ensures efficient channel utilization and transmission quality.

[0196] Mode 2: Channel Occupancy Time (COT) reporting for carrier aggregation of licensed and unlicensed carriers

[0197] Mode 2 is a common carrier aggregation method. In Mode 2, licensed and unlicensed carriers can be used simultaneously, providing higher overall data rates.

[0198] In carrier aggregation, licensed and unlicensed carriers typically have different spectrum widths and transmission capabilities. Licensed carriers typically have wider spectrum bandwidths and higher transmission rates, while unlicensed carriers are relatively narrow and limited. Therefore, when performing carrier aggregation, there may be an imbalance in load distribution between licensed and unlicensed carriers. This imbalance may cause some carriers to be overloaded while others are underloaded. Overloaded carriers may experience performance degradation, increased transmission latency, or unstable connections, while underloaded carriers may not be able to fully utilize their potential.

[0199] To overcome this imbalance, carrier aggregation needs to consider reasonable load distribution and dynamic scheduling to ensure load balance between licensed carriers and unlicensed carriers.

[0200] To this end, the present disclosure provides the following solution: When a UE is configured with carrier aggregation of Mode 2 licensed and unlicensed carriers, if the first node (e.g., Rx UE) performs LBT on the unlicensed carrier, the COT can be sent to the second node (e.g., Tx UE) via SCI signaling on the licensed carrier.

[0201] FIG6A illustrates a schematic flow chart of a sidelink communication method performed by a first node according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, a sidelink communication method is provided, performed by a first node, comprising: Operation 610: transmitting, by the first node in sidelink communication, sidelink control information (SCI) signaling to a second node in sidelink communication, the SCI signaling being carried by a first carrier, wherein the SCI signaling includes a channel occupancy time (COT) on a second carrier and a cell index or carrier index associated with the second carrier.

[0202] Through the above embodiments, the present disclosure solves the technical problem of how to transmit SCI signaling, so that SCI signaling can be transmitted in an appropriate manner and the channel occupancy time can be indicated at the same time, thereby coordinating the transmission between multiple communication entities, avoiding conflicts and interference, and improving the efficiency and reliability of side link communications.

[0203] FIG6B illustrates a schematic diagram of exemplary signaling interactions between a first node and a second node in sidelink communication according to some embodiments of the present disclosure.

[0204] According to some embodiments of the present disclosure, as shown in FIG6B , a sidelink communication method is provided. The method may be performed by a first node and includes: transmitting, by the first node in sidelink communication, sidelink control information (SCI) signaling to a second node in sidelink communication, the SCI signaling being carried by a first carrier, wherein the SCI signaling includes a channel occupancy time (COT) on a second carrier and a cell index or a carrier index associated with the second carrier.

[0205] According to some embodiments of the present disclosure, the COT is obtained by the first node after performing a listen-before-talk (LBT) process on the second carrier.

[0206] According to some embodiments of the present disclosure, the first carrier is a licensed carrier, and the second carrier is an unlicensed carrier.

[0207] According to some embodiments of the present disclosure, the first node is a receiving user equipment Rx UE, and the second node is a transmitting user equipment Tx UE.

[0208] Therefore, in the scenario of carrier aggregation, the Rx UE sends the COT of the second carrier (such as the unlicensed carrier) on the first carrier (such as the licensed carrier), which can achieve the effect of cross-carrier scheduling and realize carrier balancing.

[0209] Through the above embodiments, the present disclosure solves the technical problem of how to transmit side link control information, so that the side link control information can be transmitted in an appropriate manner and the channel occupancy time can be indicated at the same time, thereby coordinating the transmission between multiple communication entities, avoiding conflicts and interference, and improving the efficiency and reliability of side link communications.

[0210] LBT failure indication enhancement

[0211] In NR-U, UE uplink transmissions are based on uplink grants (UL grants) sent by the base station (e.g., gNB). However, before transmission, the UE needs to perform LBT. If the UE experiences LBT failure on a resource block set (RB set) in the physical layer L1, all RB sets in the entire timeslot cannot be transmitted. This is because the base station (e.g., gNB) schedules a transport block (TB) for the entire timeslot and cannot determine whether the UE has transmitted on the RB set where LBT failed.

[0212] The same principle applies to SL-U. If a UE experiences an LBT failure on a certain RB set in the physical layer L1, it cannot use other RB sets in the same timeslot. This is because the sidelink control information (SCI) has already indicated all RB sets in the timeslot. Therefore, the Rx UE cannot receive all RB sets and therefore cannot transmit.

[0213] In response to the above problems and research on related technologies, the present disclosure proposes the following solution: the UE can indicate that the RB set is unavailable from the PHY layer (applicable to a single LBT failure) or the MAC layer (applicable to a C-LBT failure).

[0214] Option 1: PHY signaling indicates that the RB set is unavailable.

[0215] One or more indication bits may be added to the SCI signaling (eg, SCI 2A / B) to indicate the index of certain unavailable RB set(s).

[0216] According to some embodiments of the present disclosure, a sidelink communication method is provided. The method may be performed by a first node and includes: preparing, by the first node in the sidelink communication (e.g., in some cases, the first node itself configures; in some other cases, it is not excluded that the first node reports the configuration requirements to a network side (e.g., a core network CN), and the network side transmits the configured signaling back to the first node, etc.) control signaling related to the sidelink communication; and transmitting, by the first node, the control signaling to a second node in the sidelink communication to indicate that a listen-before-talk (LBT) method has failed.

[0217] According to some embodiments of the present disclosure, the control signaling may be side link control information SCI signaling, and the SCI signaling may include an index of an RB set that is unavailable due to the LBT failure.

[0218] Option 2: When the MAC layer determines that continuous LBT failures have occurred, it indicates through a MAC CE that the RB set is unavailable.

[0219] When a node receives LBT failure indications continuously from the L1 layer at the MAC layer, it can be determined that continuous LBT failures have occurred. Therefore, the MAC layer needs to notify the peer UE via MAC CE (for example, by extending the MAC CE in the related art).

[0220] Since the time slots of the entire carrier are unavailable, other carriers can be used to send MAC CE for indication.

[0221] According to some embodiments of the present disclosure, the control signaling is a medium access control MAC control element CE, and the MAC CE includes an index of an RB set that is unavailable due to the LBT failure.

[0222] According to some embodiments of the present disclosure, the MAC CE may further include an index of a carrier associated with the RB set.

[0223] FIG7A illustrates a schematic flow chart of a sidelink communication method performed by a first node according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, a sidelink communication method is provided, performed by a first node, comprising: operation 710: preparing, by the first node in sidelink communication, control signaling related to the sidelink communication; operation 712: transmitting, by the first node, the control signaling to a second node in the sidelink communication, indicating a listen-before-talk (LBT) failure; wherein the control signaling is sidelink control information (SCI) signaling, and the SCI signaling includes an index of a resource block set (RB set) that is unavailable due to the LBT failure.

[0224] Through the above embodiments, the present disclosure solves the problem that when part of the carriers of the RB set fail, the RB set in the entire time slot is unavailable, resulting in waste.

[0225] According to some embodiments of the present disclosure, the control signaling is a medium access control (MAC) control element (CE), and the MAC CE includes an index of an unavailable RB set due to the LBT failure. According to some embodiments of the present disclosure, the MAC CE also includes an index of a carrier associated with the RB set.

[0226] Figure 7B illustrates a schematic diagram of a MAC CE bitmap according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, the MAC CE bitmap extension includes, for example, the following extensions: Each bit in the bitmap indicates whether LBT has occurred for the corresponding RB set index (RB set index). Each bit in the bitmap corresponds to the index of each RB set that has become unavailable due to an LBT failure. Examples of the bits include C0, C1, C2, C3, C4, C5, C6, and C7.

[0227] According to some embodiments of the present disclosure, the control signaling is included in an LBT failure indication message. According to some embodiments of the present disclosure, the control signaling is transmitted together with the LBT failure indication message by the first node to the second node.

[0228] According to some embodiments of the present disclosure, the method further includes: transmitting, by the first node, an LBT failure cancellation message to the second node, the LBT failure cancellation message including at least one of a carrier index and an RB set index. This can address the following technical issue: after consecutive LBT failures occur in the SL, the TX UE will not use this block of resources, resulting in long-term waste.

[0229] According to some embodiments of the present disclosure, the LBT failure cancellation message is transmitted by the first node based on performing LBT recovery on a carrier corresponding to at least one of the carrier index and the RB set index.

[0230] Figure 7C illustrates a schematic diagram of an exemplary signaling interaction between a first node and a second node in sidelink communication according to some embodiments of the present disclosure. As shown in Figure 7C, the first node in sidelink communication transmits an LBT failure indication message to the second node.

[0231] According to some embodiments of the present disclosure, the control signaling may be included in a listen-before-talk (LBT) failure indication message.

[0232] According to some embodiments of the present disclosure, the control signaling may be transmitted from the first node to the second node together with the LBT failure indication message.

[0233] Through the above embodiments, the present disclosure solves the technical problem of how to indicate resource availability in a side link, thereby facilitating communication decision-making and adjustment between nodes in side link communication.

[0234] LBT failed to cancel

[0235] LBT failure recovery primarily relies on resource reselection. During resource reselection, the RB set in which C-LBT occurred must be excluded. Furthermore, LBT failure cancellation differs between the Uu interface and the sidelink. The Uu interface relies on a successful random access, while LBT failure cancellation on the sidelink primarily relies on upper-layer MAC reset and parameter reconfiguration, without any interaction between the two peer UEs.

[0236] However, in Mode 2 on the sidelink, since resources are selected by the node (e.g., Tx UE), once the Tx UE receives an LBT failure indication, it will never use the resources where the LBT failure occurred. The Tx UE will perform resource reselection to recover from the LBT failure.

[0237] Therefore, the Uu interface can recover LBT through random access, but there is no random access process on the side link. Therefore, to solve the problem that the Tx UE on the side link no longer uses the resources that have experienced LBT failure, the present disclosure provides the following solution.

[0238] According to some embodiments of the present disclosure, as shown in FIG7C , the method may further include: transmitting, by the first node, an LBT failure cancellation message to the second node, the LBT failure cancellation message including at least one of a carrier index and a resource block set RB set index.

[0239] According to some embodiments of the present disclosure, the LBT failure cancellation message is transmitted by the first node based on performing LBT recovery on a carrier corresponding to at least one of the carrier index and the RB set index.

[0240] Therefore, by introducing the LBT failure cancellation message, it is possible to indicate to the peer UE that the resources that were previously unavailable have recovered from the LBT failure. The purpose of introducing this message is to indicate to the peer UE (e.g., Tx UE) that a resource that has experienced an LBT failure can be used again. It should be noted here that LBT failure is defined at the RB set granularity. That is, LBT failure is expressed in the name of RB set rather than in the name of carrier. When referring to the occurrence of LBT failure, it means that LBT failure has occurred in a certain RB set.

[0241] Through the above-described embodiments, the present disclosure solves the technical problem of how to indicate resource availability in the sidelink, thereby facilitating communication decision-making and coordination between nodes in sidelink communications. Furthermore, by introducing LBT failure cancellation messages, previously discarded carrier resources can be reused, improving resource utilization and sidelink communication efficiency.

[0242] This document describes a method for enhancing unlicensed spectrum carrier aggregation in sidelink communications, applicable to communications between a first node and between a first node and a second node. However, these inventive concepts, methods, apparatuses, devices, computer-readable storage media, chips, and computer program products are not limited to sidelink communications and can be extended to other communication scenarios to achieve the same technical benefits and effects.

[0243] In these scalable communication scenarios, the first node and / or the second node can be entities such as user equipment (UE), base stations (such as gNB, eNodeB, transmission reception point (TRP), next-generation communication NodeB or Wi-Fi access point, etc.), or network elements. User equipment (UE) refers to a device used for communication at the user end, such as a mobile phone, and can also be called a terminal, mobile station, or mobile terminal. UE can be a variety of devices, including but not limited to mobile phones, tablets, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals for industrial control, wireless terminals for autonomous driving, wireless terminals for remote medical surgery, wireless terminals for smart grids, wireless terminals for environmental monitoring, wireless terminals for smart cities, and wireless terminals for smart homes.

[0244] Furthermore, UEs and base stations can be deployed in different environments, including but not limited to indoors, outdoors, as handheld devices, in vehicles, or even on water, in the air, on airplanes, drones, or satellites.

[0245] Therefore, although this document describes methods and devices for sidelink communication, the inventive concepts and technologies contained therein can be extended to other communication scenarios and are expected to achieve the same technical benefits and effects. It is easy to understand that these inventive concepts have broad applicability and scalability, whether in communications between different types of base stations and user equipment, or in communications in different deployment environments.

[0246] It should be noted that the above steps are merely examples and do not limit the scope of the present invention. Various modifications and variations can be made to the steps without departing from the spirit and scope of the present invention.

[0247] The order of the described steps (signaling / boxes) is not intended to be construed as a limitation, and any number of the described steps (signaling / boxes) may be skipped or combined in any order to implement a method or an alternative method.

[0248] The present disclosure describes examples of communication between terminals and network element components in a network architecture in the above embodiments, which are mainly for illustrative purposes and not restrictive.

[0249] The order of the steps (signaling / boxes) described is not intended to be interpreted as limiting, and any number of the steps (signaling / boxes) described can be skipped or combined in any order to implement a method or alternative method. Typically, any of the components, modules, methods, and operations described herein can be implemented using software, firmware, hardware (e.g., fixed logic circuitry), manual processing, or any combination thereof. Some operations of the example methods can be described in the general context of executable instructions stored on a computer-readable memory locally and / or remotely on a computer processing system, and implementation methods can include software applications, programs, functions, and the like. Alternatively or in addition, any function described herein can be performed, at least in part, by one or more hardware logic components, such as, but not limited to, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), an application specific standard product (ASSP), a system on a chip (SoC), a complex programmable logic device (CPLD), and the like.

[0250] In addition, the signaling described in the embodiments of the present disclosure can be implemented in any manner known in the art. For example, the signaling can be explicit and / or implicit. In addition, the steps (signaling / frames) shown are for illustrative purposes only and are not intended to limit the present application.

[0251] Various aspects of the present invention may be understood from the following enumerated exemplary embodiments:

[0252] According to an example embodiment, with reference to FIG8 , a sidelink communication method is provided, performed by a first node, comprising:

[0253] Step S801: The first node in the sidelink communication configures a sidelink reconfiguration message to have a carrier aggregation indicator, where the carrier aggregation indicator indicates a primary carrier in a sidelink carrier aggregation (SL CA);

[0254] Step S802: the first node transmits the sidelink reconfiguration message to the second node in the sidelink communication; and

[0255] Step S803: The first node receives a side link reconfiguration completion message from the second node, wherein the second node receives the side link reconfiguration message and sends the side link reconfiguration completion message after completing the configuration according to the side link reconfiguration message.

[0256] According to an example embodiment, with reference to FIG9 , a sidelink communication method is provided, performed by a first node, comprising:

[0257] Step S901: The first node in the sidelink communication is triggered to perform the reselection in response to a trigger condition being satisfied.

[0258] According to an example embodiment, with reference to FIG10 , there is provided a sidelink communication method, performed by a first node, comprising:

[0259] Step S1001: The first node in the sidelink communication configures sidelink control information SCI signaling, where the SCI signaling indicates resources for transmitting a physical sidelink feedback channel PSFCH by the second node in the sidelink communication.

[0260] The PSFCH (feedback is the resources of the channel PSFCH, why PSFCH is explained here) is transmitted by the second node based on the physical side link shared channel PSSCH transmitted by the first node.

[0261] According to an example embodiment, with reference to FIG11 , there is provided a sidelink communication method, performed by a first node, comprising:

[0262] Step S1101: The first node in the sidelink communication transmits sidelink control information (SCI) signaling to the second node in the sidelink communication, where the SCI signaling is carried by a first carrier.

[0263] The SCI signaling includes the channel occupancy time COT on the second carrier and a cell index or a carrier index associated with the second carrier.

[0264] According to an example embodiment, with reference to FIG12 , there is provided a sidelink communication method, performed by a first node, comprising:

[0265] Step S1201: The first node in the sidelink communication prepares control signaling related to the sidelink communication;

[0266] Step S1202: The first node transmits the control signaling to the second node in the sidelink communication to indicate that the listen-before-talk (LBT) fails.

[0267] According to an example embodiment, the above method may further include:

[0268] Step S1203: The first node transmits an LBT failure cancellation message to the second node, where the LBT failure cancellation message includes at least one of a carrier index and a resource block set (RB set) index.

[0269] According to an example embodiment, a device in a sidelink communication system is provided, wherein the device is configured to perform a method according to any one of the above embodiments, examples, or example embodiments. The device may be a first node, a Tx UE, or an Rx UE described herein, etc.

[0270] According to an example embodiment, a chip is provided, comprising: a processor for calling and running a computer program from a memory, so that a device equipped with the chip executes a method according to any one of the above embodiments, examples, or exemplary embodiments.

[0271] According to an example embodiment, there is provided a computer-readable storage medium for storing a computer program, wherein the computer program causes a computer to execute a method according to any one of the above-mentioned embodiments, examples, or exemplary embodiments.

[0272] According to an example embodiment, a computer program product is provided, comprising a computer program / instruction, which, when executed by a processor (e.g., by the processor or an apparatus, device, computer or machine including the processor), implements a method according to any one of the above-mentioned embodiments, examples, or example embodiments.

[0273] FIG13 is a block diagram of an example system 700 for wireless communication according to an embodiment of the present disclosure. The embodiments described herein can be implemented into a system using any appropriately configured hardware and / or software. FIG13 illustrates system 700, including radio frequency (RF) circuitry 710, baseband circuitry 720, processing unit 730, memory / storage 740, display 750, camera 760, sensor 770, and input / output (I / O) interface 780, coupled to one another as shown.

[0274] The processing unit 730 may include circuits, such as, but not limited to, one or more single-core or multi-core processors. The processor may include any combination of general-purpose processors and special-purpose processors, such as a graphics processor and an application processor. The processor may be coupled to a memory / storage and configured to execute instructions stored in the memory / storage to enable various applications and / or operating systems running on the system. The RF circuit 710, baseband circuit 720, processing unit 730, memory / storage 740, display 750, camera 760, sensor 770, and I / O interface 780 are well-known components of the system 700, such as, but not limited to, laptop computing devices, tablet computing devices, netbooks, ultrabooks, smartphones, etc. In addition, instructions as a software product may be stored in a computer-readable storage medium. The software product in the computer is stored in a storage medium and includes multiple commands for a computing device (such as a personal computer, server, or network device) to execute all or some of the steps disclosed in the embodiments of the present disclosure. The storage medium includes a USB disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a floppy disk, or other types of media capable of storing program codes.

[0275] The embodiments of the present disclosure are a combination of techniques / processes that may be employed in 3GPP specifications to create a final product.

[0276] While the present disclosure has been described in connection with what is considered to be the most practical and preferred embodiment, it is to be understood that the disclosure is not limited to the disclosed embodiment, but is intended to cover various arrangements that may be made without departing from the scope of the broadest interpretation of the appended claims.

Claims

1. A sidelink communication method, comprising: Sending a carrier aggregation indicator, wherein the carrier aggregation indicator is used to indicate a primary carrier and a secondary carrier in sidelink carrier aggregation; and Receiving a message indicating that the configuration of the primary carrier and the secondary carrier is completed, wherein the message indicating that the configuration of the primary carrier and the secondary carrier is completed is returned by a node that receives the carrier aggregation indicator.

2. The method according to claim 1, wherein, The carrier aggregation indicator includes at least one of a cell ID or a carrier index.

3. The method according to claim 1 or 2, wherein The sidelink carrier aggregation includes: Performing carrier aggregation between an authorized carrier and another authorized carrier, Performing carrier aggregation between an authorized carrier and an unauthorized carrier, or Performing carrier aggregation between an unauthorized carrier and another unauthorized carrier.

4. The method according to claim 1 or 2, wherein The primary carrier is used to transmit a control protocol data unit (PDU) of a packet data convergence protocol (PDCP).

5. The method according to claim 1 or 2, wherein The sending of the carrier aggregation indicator includes: sending a sidelink reconfiguration message, where the sidelink reconfiguration message includes the carrier aggregation indicator.

6. A resource reselection method in sidelink communication, comprising: Configuring one or more first listen-before-talk (LBT) failure counters under carrier aggregation (CA), where the first LBT failure counter is configured to record the number of LBT failures that occur under the CA, and the first LBT failure counter corresponds to a first threshold; Configuring a second LBT failure counter under non-CA, where the second LBT failure counter is configured to record the number of LBT failures that occur under the non-CA, where the second LBT failure counter corresponds to a second threshold, and the first threshold is greater than the second threshold; and Performing resource reselection when the value of the first LBT failure counter reaches the first threshold.

7. The method according to claim 6, wherein The one or more first LBT failure counters are configured to respectively record the number of LBT failures that occur on multiple carriers under the CA; The performing of the resource reselection when the value of the first LBT failure counter reaches the first threshold includes: When the value of the first LBT failure counter corresponding to any one of the multiple carriers reaches the first threshold, performing the resource reselection for the any one carrier.

8. The method according to claim 6, wherein The one or more first LBT failure counters are configured to record the combined number of LBT failures that occur on multiple carriers under the CA; The performing of the resource reselection when the value of the first LBT failure counter reaches the first threshold includes: When the value of the first LBT failure counter reaches the first threshold, performing the resource reselection on the carrier with a larger number of LBT failures among the multiple carriers.

9. The method according to claim 6, wherein The first LBT failure counter is configured to record the number of LBT failures that occur on an unauthorized carrier under the CA; The performing of the resource reselection when the value of the first LBT failure counter reaches the first threshold includes: When the value of the first LBT failure counter reaches the first threshold, perform resource reselection for the unlicensed carrier.

10. A carrier reselection method in sidelink communication, comprising: Receiving a listen-before-talk LBT failure message regarding a target carrier; And In response to the LBT failure message matching a preset condition, performing carrier reselection for the target carrier; Wherein, the preset condition includes: The first occurrence of LBT failure on the target carrier; or Continuous LBT failures occurring on the target carrier.

11. A sidelink communication method, performed by a first node, comprising: Configuring, by the first node in sidelink communication, sidelink control information SCI signaling, the SCI signaling indicating resources for a second node in the sidelink communication to transmit a physical sidelink feedback channel PSFCH, Wherein, the resources of the PSFCH are transmitted by the second node based on receiving a physical sidelink shared channel PSSCH transmitted by the first node; Wherein, the resources for the PSFCH are different from the resources for the PSSCH.

12. The method according to claim 11, wherein, The SCI signaling is transmitted on a first carrier.

13. The method according to claim 12, wherein, The SCI signaling includes a carrier index, and a second carrier corresponding to the carrier index is scheduled by the second node to carry the resources of the PSFCH.

14. The method according to claim 13, wherein, In the case of continuous listen-before-talk LBT failures occurring on the carrier originally scheduled to carry the PSFCH, the second node schedules the second carrier to carry the PSFCH.

15. The method according to claim 11, wherein, The SCI signaling includes a resource block set RB set index, and the RB set corresponding to the RB set index is configured as redundant resources.

16. The method according to claim 15, wherein, The RB set is indication information for the redundant resources of the PSFCH.

17. The method according to claim 15 or 16, wherein, The SCI signaling indicates the time slot for transmitting the PSFCH.

18. A sidelink communication method, performed by a first node, comprising: Transmitting, by the first node in sidelink communication, sidelink control information SCI signaling to a second node in the sidelink communication, the SCI signaling being carried by a first carrier, Wherein, the SCI signaling includes a channel occupancy time COT on a second carrier and a cell index or a carrier index associated with the second carrier.

19. The method according to claim 18, wherein, The COT is obtained by the first node after performing a listen-before-talk LBT process on the second carrier.

20. The method according to claim 18 or 19, wherein The first carrier is a licensed carrier, and the second carrier is an unlicensed carrier.

21. The method according to any one of claims 18 to 20, wherein The first node is a receiving user equipment Rx UE, and the second node is a transmitting user equipment Tx UE.

22. A sidelink communication method, performed by a first node, comprising: Preparing, by the first node in sidelink communication, control signaling related to the sidelink communication; Transmitting, by the first node, the control signaling to a second node in the sidelink communication to indicate a listen-before-talk LBT failure; Wherein, the control signaling is sidelink control information SCI signaling, and the SCI signaling includes an index of a resource block set RB set that is unavailable due to the occurrence of the LBT failure.

23. The method according to claim 22, wherein The control signaling is a Medium Access Control (MAC) control element (CE), and the MAC CE includes an index of an RB set that is unavailable due to the LBT failure.

24. The method according to claim 23, wherein, The MAC CE further includes an index of a carrier associated with the RB set.

25. The method according to any one of claims 22 to 24, wherein The control signaling is included in an LBT failure indication message.

26. The method according to any one of claims 22 to 25, wherein, The control signaling and the LBT failure indication message are transmitted by the first node to the second node together.

27. The method according to any one of claims 22 to 26, further comprising: transmitting, by the first node to the second node, an LBT failure cancellation message, the LBT failure cancellation message including at least one of a carrier index and an RB set index.

28. The method according to claim 27, wherein, The LBT failure cancellation message is transmitted by the first node based on performing LBT recovery on a carrier corresponding to at least one of the carrier index and the RB set index.

29. A device in a sidelink communication system, the device being configured to perform the method according to any one of claims 1 to 28.

30. A chip, the chip comprising: A processor, configured to call and run a computer program from a memory, so that the device installed with the chip performs the method according to any one of claims 1 to 28.

31. A computer-readable storage medium, wherein, For storing a computer program, the computer program causing a computer to perform the method according to any one of claims 1 to 28.

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