WO2025129449A1 - Sidelink communication method, device, chip, and computer storage medium - Google Patents

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

The present disclosure relates to the field of wireless communications, and in particular to a side link communication method, a resource reselection method in side link communication, a carrier reselection method in side link communication, and a device, a chip, and a computer-readable storage medium in a side link communication system.

Background Art

Licensed carriers or authorized spectrum refer to frequency bands that are designated and allocated to specific users or operators by the government or relevant agencies. Users or operators need permission or authorization to use these frequency bands for communication. Licensed carriers usually 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 usually licensed spectrum. The advantage of licensed spectrum is that it has certain protection and management mechanisms to ensure the rational allocation of spectrum resources and interference-free operation.

Unlicensed carriers or unlicensed spectrum refers to frequency bands that are not exclusively used by specific users or operators. Any user can use them freely 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 it needs to comply with specific technical standards and regulations to avoid interfering with the communications of other users. Unlicensed spectrum is usually used to provide short-range, low-power communications, such as Wi-Fi and (Bluetooth), etc.

Licensed carriers and unlicensed carriers are two different types of carriers used for carrier aggregation in wireless communications. Carrier aggregation technology can utilize both 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.

In sidelink communications, the 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 the sidelink communication scenario.

Summary of the invention

At least to overcome the above technical problems, the present disclosure proposes a sidelink communication method, a resource reselection method in sidelink communication, a carrier reselection method in sidelink communication, a device in a sidelink communication system, a chip and a computer-readable storage medium. The purpose of enhancing unlicensed carriers in carrier aggregation for sidelink communications is achieved.

According to one aspect of the present disclosure, there is provided a side link 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 a sidelink carrier aggregation; and

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.

According to one aspect of the present disclosure, a resource reselection method in side link communication is provided, comprising:

Configure one or more first listen-before-send LBT failure counters under carrier aggregation CA, where the first LBT failure counter is configured to record the number of LBT failures occurring under the CA, and the first LBT failure counter corresponds to a first threshold;

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

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

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

receiving a listen-before-send LBT failure message for a target carrier; and

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

The preset conditions include:

The first LBT failure occurs on the target carrier; or

Consecutive LBT failures occur on the target carrier.

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

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,

The PSFCH resource is transmitted by the second node based on receiving a physical side link shared channel PSSCH transmitted by the first node;

The resources used for the PSFCH are different from the resources used for the PSSCH.

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

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,

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

According to one aspect of the present disclosure, a sidelink communication method is performed by a first node, including:

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

The control signaling is transmitted by the first node to the second node in the sidelink communication to indicate that the listen-before-talk (LBT) fails;

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

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 aspect of the embodiments of the present disclosure.

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.

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 a method of an embodiment of any aspect of the present disclosure.

According to one aspect of the present disclosure, a computer program product is provided, including a computer program, wherein the computer program enables a computer to execute a method according to an embodiment of any aspect of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

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 obtain other drawings based on these drawings without creative work.

FIG. 1 illustrates a schematic diagram of an exemplary cellular network according to some embodiments of the present disclosure.

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

FIG. 3A illustrates a schematic flow chart of a side link communication method according to some embodiments of the present disclosure.

3B 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.

FIG3C illustrates a schematic flow chart of a resource reselection method in sidelink communication according to some embodiments of the present disclosure.

FIG3D illustrates a schematic flow chart of a carrier reselection method in sidelink communication according to some embodiments of the present disclosure.

FIG. 4A illustrates a schematic flow chart of a sidelink communication method performed by a first node according to some embodiments of the present disclosure.

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.

FIG. 5 illustrates an exemplary partitioning of a resource block set RB set in side link communication according to some embodiments of the present disclosure. picture.

FIG6A illustrates a schematic flow chart of a side link communication method performed by a first node according to some embodiments of the present disclosure.

FIG6B illustrates a schematic diagram of an exemplary signaling interaction between a first node and a second node in side link communication according to some embodiments of the present disclosure.

FIG7A illustrates a schematic flow chart of a side link communication method performed by a first node according to some embodiments of the present disclosure.

Figure 7B illustrates a schematic diagram of a bit map of a MAC CE according to some embodiments of the present disclosure.

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.

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

FIG9 illustrates a schematic flow chart of a side link communication method according to some embodiments of the present disclosure.

FIG10 illustrates a schematic flow chart of a side link communication method according to some embodiments of the present disclosure.

FIG11 illustrates a schematic flow chart of a side link communication method according to some embodiments of the present disclosure.

FIG12 illustrates a schematic flow chart of a side link communication method according to some embodiments of the present disclosure.

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

DETAILED DESCRIPTION

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

In the present disclosure, "A or B" may mean "only A", "only B", or "both A and B".

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, C".

A slash (/) or a comma used in the present disclosure 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".

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".

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".

In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined.

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 a variety of alternative arrangements.

FIG. 1 illustrates a schematic diagram of an exemplary cellular network according to some embodiments of the present disclosure. As shown, a schematic diagram of a cellular network formed by three base stations (e.g., eNBs or gNBs depending on the specific cellular standard and terminology) is exemplarily depicted. Typically, base stations will be deployed by a cellular network operator to provide geographic coverage for UEs in the area. The base stations form a radio access network (RAN). The base stations provide wireless coverage for UEs in the area or cell in which they are located. The base stations are interconnected via an X2 interface and connected to the core network via an 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 sidelink communication. The interface and component names associated with FIG. 1 are used as examples only, and different systems operating on the same principles may use different nomenclature.

A base station contains hardware and software for implementing RAN functions to facilitate communication between the base station and the core network or other base stations, control and data signal transmission between the core network and UEs, and wireless communication between the base station and associated UEs. The core network includes hardware and software for implementing network functions, such as overall network management and control, and routing of calls and data.

In vehicle to vehicle (V2V) applications, vehicle UEs can be integrated into vehicles such as cars, trucks, and buses. These vehicle UEs can communicate with each other in both in-coverage mode and out-of-coverage mode. In-coverage mode means that the base station can manage and allocate resources to UEs within the base station coverage, and out-of-coverage mode does not require any base station management and 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.

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

In addition to the uplink/downlink communication between the UE and the base station, side link communication in which the UEs communicate directly with each other can also be implemented. Figure 2 shows the base stations forming the RAN, as well as the transmitter (transmitter, Tx) UE 150 and the receiver (receiver, Rx) UE 152 in the RAN. The base station 102 is arranged to wirelessly communicate with any one of the Tx UE 150 and the Rx UE 152 through respective connections 154. The Tx UE 150 and the Rx UE 152 are arranged to wirelessly communicate with each other through the side link 156.

Resource pools for transmission resources are used to manage resources and allocations and to manage interference between potential 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.

Two operation 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 this base station.

Mode 2 is applicable when the sidelink service operates outside the coverage of the cellular base station, at which time, the UE needs to schedule resources by itself. For fair utilization, the UE usually uses a sensed based transmission resource allocation. Selecting resources involves two steps. In step 1, the UE will identify the resources that are considered to be 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 as candidates (for example, resources reserved by another UE with SL RSRP above a threshold). The step of selecting resources may be a random selection, and may have constraints such as HARQ timing and delays 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 indicating these resources. The receiver of the SCI message (which may be a single UE in unicast, a group of UEs in multicast, or all accessible UEs in broadcast) can learn the details of the transmission that can be expected through the SCI. The SCI message is the control information required to decode the sidelink data content and is also a reserved resource indication. The first-stage SCI message is transmitted in the physical sidelink control channel (PSCCH), and the second-stage SCI message is transmitted in the physical sidelink shared channel (PSSCH). The UE can reserve transmission resources for the first transmission of the transport block (TB) of the data, and can also reserve transmission resources for repeated transmission of TB to improve reliability when the initial transmission fails.

Configuration of primary and secondary carriers for sidelink carrier aggregation

Sidelink communication has received a lot of attention in 3GPP (3rd Generation Partnership Project), especially in 5G technology. It is considered a key function that can support many new application scenarios, such as connected vehicles, the Internet of Things, and public safety communications.

User equipment (UE) can communicate directly with other nearby devices through sidelink communication without relaying through the base station. The advantages of this direct communication are low latency and high reliability, while also reducing the pressure on the base station and network congestion. Through sidelink communication, user equipment can perform fast and reliable point-to-point or multicast communication under specific service quality requirements.

Sidelink communications in 3GPP standardize various technologies and protocols 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.

In the sidelink communication of 3GPP Rel_18 and previous versions, cross-carrier scheduling is not supported. However, the concept of carrier aggregation (CA) was introduced in Rel_18, but due to time constraints, it was explicitly stated that cross-carrier scheduling would not be implemented in Rel_18. However, as the standard evolves, it is expected that cross-carrier scheduling will likely be introduced in sidelink communication in Rel_19 starting in 2024. In cross-carrier scheduling, a series of issues need to be addressed, which will be reflected and addressed in this article.

The Rel_18 work item description (WID) clearly states that no distinction is made between primary carriers and secondary carriers in terms of carrier aggregation (CA).

In the related art, when a conventional UE and a base station communicate via a Uu interface, the PCell associated with the primary carrier The configuration of the SCell is usually placed in CellGroupConfig, while the configuration of the SCell associated with the secondary carrier is located in sCellToAddModList in CellGroupConfig. Therefore, the designation and distinction of the primary carrier and the secondary carrier in carrier aggregation can be achieved. However, as mentioned above, in the sidelink technology of Rel_18 version, 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 like carrier aggregation under the Uu interface (for example, configuring the RRC configuration of the secondary carrier).

In addition, in the related art, the PDCP (Packet Data Convergence Protocol) configuration generally includes a primary path. In this configuration, the primary path can be specified by a logical channel. This is because under the PDCP repeated transmission mechanism, the two RLC (Radio Link Control) entities must be located on two carriers, so specifying a carrier is equivalent to specifying the primary path.

However, in sidelink communication, there is generally no concept of cell group. The introduction of cell group can be used to describe the association relationship and configuration information between UE and base station in main link communication. In sidelink communication, the main focus is on the setting and management of the sidelink, and the Cell Group configuration in the main link communication is not involved. Therefore, in the sidelink, a node (for example, the first node (such as Tx UE) etc.) cannot specify the main path through the logical channel ID of a cell group, and thus cannot specify the main carrier in carrier aggregation.

In view of the above problems and research on related technologies, in side link communication, when it is necessary to perform carrier aggregation on authorized carriers and unauthorized 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 the side link communication.

Fig. 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 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 receiving the carrier aggregation indicator.

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 sends a carrier aggregation indicator to the second node in the sidelink communication, wherein the carrier aggregation indicator is used to indicate the main carrier and the secondary carrier in the sidelink carrier aggregation; and the first node receives a message from the second node that the configuration of the main carrier and the secondary carrier is completed, wherein the message that the configuration of the main carrier and the secondary carrier is completed is returned by the second node that receives the carrier aggregation indicator. As a result, each relevant node can distinguish between the main carrier and the secondary carrier during carrier aggregation CA, thereby improving the efficiency and reliability of the sidelink communication.

According to some embodiments of the present disclosure, the sending of 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.

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

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

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 may be performed by a first node and includes: the first node in the sidelink communication configures a 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 a sidelink reconfiguration message to a 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.

In some examples, when an index of a candidate sidelink carrier is included in a 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 a primary carrier in a sidelink carrier aggregation SL CA.

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

It can be understood that the above examples are only provided for the purpose of exemplary explanation, and the present disclosure does not impose any limitation on the form of the carrier aggregation indicator.

In some examples, the sidelink reconfiguration message may be an RRC sidelink reconfiguration message (RRCReconfigurationSidelink). Accordingly, the sidelink reconfiguration completion message may be an RRC sidelink reconfiguration completion message (RRCReconfigurationCompleteSidelink). Of course, the sidelink reconfiguration message may 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 may 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 communications to ensure the correct operation and performance optimization of the sidelink.

In order to enable the Tx UE in the sidelink communication to distinguish between the two carriers, the sidelink reconfiguration messages (eg RRCReconfigurationSidelink) needs to include carrier configuration information, such as carrier index and frequency configuration and other related information. According to some embodiments of the present disclosure, the carrier aggregation indicator includes at least one of a cell ID or a carrier index.

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, and the like.

As mentioned above, in the sidelink technology of Rel_18 version, the primary carrier and the secondary carrier are not distinguished. Therefore, in the RRC configuration, the secondary carrier is not configured through the primary carrier like the carrier aggregation under the Uu interface. In view of this, the node (for example, the first node (such as Tx UE) etc.) cannot configure a primary RLC entity to send PDCP control protocol data unit PDU (PDCP control PDU) under the air interface of the sidelink communication like the Uu interface.

According to some embodiments of the present disclosure, the primary carrier can be used to transmit a control protocol data unit PDU of a 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.

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

Increased latency requirements for sidelink communications

Sidelink communications have strict latency requirements in V2X services. This is because in V2X, if the latency is too high, the vehicle may receive the sidelink data only after a traffic accident occurs, which is completely unacceptable and must be avoided.

In the related art, URLLC (Ultra-reliable and Low Latency Communication) services based on the Uu interface need to use licensed spectrum. However, as mentioned above, on the side link, basically all services have strict requirements for low latency. By performing carrier aggregation on the side link, aggregation of licensed carriers and unlicensed carriers can be achieved, so the unlicensed carriers on the side link also have a strong need to achieve low latency.

Based on the research of related technologies, it is found that when the UE cannot obtain available transmission resources through the Listen-Before-Talk (LBT) mechanism on the side link, it will report LBT failure. If multiple LBT failures occur, it will lead to resource reselection, for example. However, this process consumes a lot of time.

According to some embodiments of the present disclosure, a side link communication method is provided, which can be used to control a first node in a side link to perform reselection. The method can be performed by the first node and includes: the first node in the side link communication responds to a trigger condition is satisfied and triggered to perform the reselection.

The above method can bring the following technical benefits.

Reduce delay: Triggering the first node to perform reelection can reduce the time wasted in the entire reelection process. Once the triggering condition is met, the first node can perform reelection as soon as possible, thereby reducing communication delay.

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

Enhanced reliability: Reselection can be performed quickly after the trigger condition is met to improve the reliability of sidelink communication. By reducing the time required for reselection, the risk of packet loss and communication interruption can be reduced, thereby enhancing the reliability of the overall system (such as an autonomous driving system using V2X communication).

Thus, the first node can quickly perform reselection in response to meeting the trigger condition, which can effectively shorten the time required for reselection in the side link communication, improve the efficiency of communication, reduce delays, and enhance the reliability of communication.

3C 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, including: operation 330: configuring one or more first listen-before-send LBT failure counters under carrier aggregation CA, wherein the first LBT failure counter is configured to record the number of LBT failures occurring under the CA, and the first LBT failure counter corresponds to a first threshold; operation 332: 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 operation 334: when the value of the first LBT failure counter reaches the first threshold, performing resource reselection.

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.

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 primary/secondary carrier is indicated in the carrier aggregation indicator. Specifically, the present disclosure provides the following exemplary options.

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

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

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.

In the related 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) etc.)) 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 related technology/protocol. When the timer expires, the node (for example, the first node) restarts the counter LB_COUNT.

In view of this, in the scenario of carrier aggregation, if one carrier has an LBT failure and the other carrier has not, it can be considered that the node in the sidelink communication (such as Tx UE) can still send data normally. Therefore, for the sidelink communication, more LBT failure indications from (one or more) carriers with LBT failure can be tolerated.

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 from a second LBT failure counter lbt-FailureInstanceMaxCount. Generally speaking, CA_lbt-FailureInstanceMaxCount is greater than lbt-FailureInstanceMaxCount.

Exemplarily, the present disclosure also introduces a new timer for determining C-LBT failure in a carrier aggregation scenario (e.g., in sidelink communication), namely CA_lbt-FailureDetectionTimer, which is used to distinguish from lbt-FailureDetectionTimer. Generally speaking, CA_lbt-FailureDetectionTimer has a smaller value than lbt-FailureDetectionTimer, which is mainly due to the need for low latency for basically all services in sidelink communication, for example.

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

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 side link communication, wherein the component carrier includes a licensed carrier and/or an unlicensed carrier.

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.

According to some embodiments of the present disclosure, the first threshold is set to be greater than the maximum allowed value of the number of LBT failures that occur on any of the component carriers without the carrier aggregation. Thus, by setting the threshold of the first counter, resource reselection can be triggered according to the carrier aggregation situation of the side link communication, so that when to trigger the reselection process can be determined more accurately, 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.

According to some embodiments of the present disclosure, the first timer is configured to be started since the last LBT failure occurred on the component carrier.

According to some other embodiments of the present disclosure, the first counter is configured to The first counter may be reset according to the second threshold, and the second threshold may be set to be smaller than the expiration time of the first timer in the absence of the carrier aggregation. Thus, the first timer is started according to the time when the most recent LBT failure occurred, ensuring that the execution of resource reselection is triggered at the correct time point. In addition, the first counter may also be reset according to the second threshold, and the second threshold 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.

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

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 the SL CA scenario.

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 having a larger number of LBT failures among the multiple carriers.

The first LBT failure counter, for example, configures a combined LBT counter for all unlicensed carriers in the SL CA scenario.

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 more failure times.

In the related art, in the scenario of non-carrier aggregation, each carrier is configured with its own independent counter for counting the number of LBT failures and a unified counting upper limit lbt-FailureInstanceMaxCount. When the number of LBT failure indications of a carrier reported via the physical layer L1 (for example, reported by a node (for example, the first node (such as Tx UE) etc.)) reaches the counting upper limit, the (continuous) LBT failure of the carrier will be triggered accordingly.

In sidelink communication, in view of the low latency requirements of the services thereon, when SL CA involves multiple unlicensed carriers, each unlicensed carrier needs to comprehensively consider the LBT failures of each unlicensed carrier (for example, the number of LBT failures reported by each). For example, assuming 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 times (for example, 6 LBT failure indications have been reported). If SL-U carrier2 does not have an LBT failure, then SL-U carrier1 can wait until the LB_COUNT count reaches 10 times (for example, 10 LBT failure indications have been reported) before performing, for example, resource reselection. However, if SL-U carrier 2 has also experienced 4 LBT failures at the same time as SL-U carrier 1 has experienced 6 LBT failures (for example, 4 LBT failure indications have been reported through the L1 layer), then SL-U carrier 2 will most likely trigger LBT failure soon. Therefore, it is necessary for SL-U carrier 1 to trigger LBT failure in advance to avoid triggering (continuous) LBT failures at the same or similar time as SL-U carrier 2 and performing centralized resource reselection, for example. That is, when SL-U carrier 1 has experienced 6 LBT failures and SL-U carrier 2 has also experienced 4 LBT failures, SL-U carrier 1 triggers (continuous) LBT failures. Failure triggers the first node to perform, for example, resource reselection, even if the count of its LB_COUNT is still 4 times away from the upper limit of 10 times.

It is understandable that there may be more than two unlicensed carriers participating in SL CA. In such scenarios, it is also necessary to comprehensively consider the LBT failures of all unlicensed carriers (such as 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 may lead to a sharp decline in the side link communication quality or even cause the side link communication to be interrupted.

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

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.

According to some embodiments of the present disclosure, the first node being triggered to perform the reselection in response to the trigger condition being satisfied 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 a large number of LBT failures have occurred.

As an example but not a limitation, assuming that SL CA involves three unlicensed carriers SL-U carrier 4, SL-U carrier 5, and SL-U carrier 6, 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. When at a certain moment, the carriers SL-U carrier 4 and SL-U carrier 5 have reported 9 and 8 LBT failure indications through the L1 layer, and SL-U carrier 6 has also reported 3 LBT failure indications, then at this time, the first node in the side link communication can be triggered to perform resource reselection for the two unlicensed carriers SL-U carrier 4 and SL-U carrier 5, 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 carrier 4 and SL-U carrier 5 is large and similar.

Thus, by setting the threshold of the second counter, resource reselection can be triggered according to the carrier aggregation situation of the side link communication, so that when to trigger the reselection process can be determined more accurately, thereby improving efficiency. In addition, this setting can provide flexibility, make the triggering condition closer to the carrier aggregation scenario, and ensure that the node (e.g., the first node) in the side link communication is triggered to perform resource reselection when appropriate.

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

Considering the case where the primary carrier in SL CA is a licensed carrier, the licensed carrier will not have the risk of LBT failure, so the resource availability is higher than that of the unlicensed carrier. Therefore, in the SL CA scenario, if the licensed carrier and the unlicensed carrier are carrier aggregated, a count upper limit with greater redundancy can be set for the LBT counter dedicated to the unlicensed carrier compared to the lbt-FailureInstanceMaxCount in the related art.

According to some embodiments of the present disclosure, the first LBT failure counter is configured to record the occurrence of The number of LBT failures on the unlicensed carrier; 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.

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.

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

According to some embodiments of the present disclosure, the third counter is configured to count the number of listen-before-talk (LBT) failures occurring 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.

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 resource reselection for the unlicensed carrier if the value of the third counter exceeds the fourth threshold.

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 (e.g., a first node) in the sidelink communication can be triggered to perform resource reselection based on the carrier aggregation situation of the sidelink communication, so that when to trigger the reselection process can be determined more accurately, 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.

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.

According to some embodiments of the present disclosure, the third counter is also configured to 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 last LBT failure occurred on the unlicensed carrier, 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 sidelink data transmission), so as to adapt to the low latency requirements of the sidelink communication.

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

As used herein, resource reselection and carrier reselection are two important steps in wireless communication, which are two independent processes, but their order may vary depending on the specific situation.

Carrier reselection refers to the selection of a better carrier frequency or channel in wireless communication. This is to optimize communication quality and avoid interference. In wireless networks, devices select the best carrier frequency based on periodic monitoring and some predefined indicators (such as signal strength, quality, interference level, etc.).

Resource reselection refers to selecting the best time domain and/or frequency domain resources in wireless communication, such as time slots, sub-carriers, code rates, etc. This is to optimize the use of wireless resources and improve data transmission efficiency. In wireless networks, devices will select appropriate resource allocation based on network conditions and communication requirements.

In some wireless communication protocols, such as LTE, carrier reselection is usually performed first, followed by resource reselection. This is because selecting a better carrier frequency is crucial to establishing a reliable physical connection, while resource reselection can better adapt to the network environment and data transmission requirements.

However, in some cases, especially in different wireless communication protocols or systems, there may be different orders. 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.

● Option 4: Define the reselection conditions for carriers in the SL scenario

3D illustrates a schematic flow chart of a carrier reselection method in sidelink communication according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, a carrier reselection method in sidelink communication is provided, comprising: operation 340: receiving a listen-before-send LBT failure message about a target carrier; operation 342: 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 on the target carrier.

By performing carrier reselection for the target carrier in response to the LBT failure message matching the preset conditions, 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 delays.

Continuous LBT failures are, for example, multiple LBT failures that occur to the UE on one carrier within a (eg, short) time range. The time range and the number of times threshold can be formulated according to actual conditions and are not limited in this disclosure.

In the 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 cannot meet the requirements, such as PDB (Packet Delay Budget), resource reselection is performed. The second round of resource selection involves LBT. If an LBT failure occurs on the 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.

In LTE LTE, carrier reselection is related to CBR (Channel Busy Rate) (e.g., per-carrier-per-priority CBR threshold for carrier selection (reselection) and per-carrier-per-priority CBR threshold for carrier retention), while in 5G NR, there is no such concept.

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.

Condition 1: When LBT fails on a carrier, carrier reselection is performed directly. This is mainly because in the event of LBT failure, there may be a possibility of long-term conflict between the carrier and Wi-Fi, so direct carrier reselection is considered.

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.

According to some embodiments of the present disclosure, the first node being triggered to perform the reselection in response to the trigger condition being satisfied may include: in the case where the LBT failure occurs on the first carrier, the first node performs the carrier reselection for the first carrier. Thereby, the risk of long-term conflict between the side link communication on the carrier and the wireless broadband communication is avoided, and the efficiency and reliability of the side link communication are improved.

Condition 2: When continuous LBT failures occur on a carrier, carrier reselection is performed. This method does not require modification of the LBT failure process. If the UE has multiple LBT failures on a carrier in a (for example, short) time range, the UE considers that there may be a possibility of long-term conflict between the carrier and Wi-Fi, and therefore considers directly reselecting the carrier.

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.

According to some embodiments of the present disclosure, the first node being triggered to perform the reselection in response to the trigger condition being satisfied may include: triggering the first node to perform the carrier reselection for the first carrier when 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 side link, facilitates the reasonable scheduling and optimization of transmission resources in the side link communication, and improves the efficiency and reliability of the side link communication.

Cross-carrier configuration of PSFCH resources

According to the PSFCH (Physical Sidelink Feedback Channel) feedback mechanism in the related art, the PSFCH resource is specified by RRC (Radio Resource Control) and Tx UE in SCI 1A (i.e., Sidelink Control Information 1A). The resource block (RB) used by each PSFCH may correspond to the RB used by 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.

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, which is performed by a first node, including: Operation 410: configuring sidelink control information SCI signaling by the first node in the sidelink communication, the SCI signaling indicating the sidelink communication used in the sidelink communication The second node transmits resources of a physical side link feedback channel PSFCH, wherein the resources of the PSFCH are transmitted by the second node based on receiving a physical side link shared channel PSSCH transmitted by the first node; wherein the resources used for the PSFCH are different from the resources used for the PSSCH.

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

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

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

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

Fig. 4B 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. As shown in the figure, the first node in the sidelink communication sends a PSSCH to the second node. The second node transmits a PSFCH to the first node in response to receiving the PSSCH.

According to some embodiments of the present disclosure, a sidelink communication method is provided, which 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 the 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 receiving a physical sidelink shared channel PSSCH transmitted by the first node.

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

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.

Feedback channel is important in wireless communication systems, and plays a vital role in achieving efficient data transmission and resource management, which is reflected in the following aspects, including but not limited to resource allocation and scheduling optimization, adaptive modulation and coding, link adaptation, interference management and suppression, etc. In view of this, with the help of the above method, all resources used to transmit PSFCH can be placed on another carrier (e.g., licensed carrier) different from the carrier (e.g., unlicensed carrier) used to transmit PSSCH (and/or SCI signaling), thereby improving the efficiency and reliability of sidelink communication.

Option 2: When continuous LBT failures occur on PSFCH resources, schedule PSFCH with another carrier, such as the authorized carrier.

According to some embodiments of the present disclosure, in the case where a continuous listen-before-talk LBT failure occurs on the carrier originally scheduled to carry the PSFCH, the second node schedules the second carrier to carry the PSFCH. Thus, when a continuous LBT failure occurs 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) different from the carrier (e.g., an unlicensed carrier) used to transmit the PSSCH (and/or SCI signaling), thereby improving the efficiency and reliability of the sidelink communication.

Option 3: Scheduling of PSFCH across resource block sets (RB sets)

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

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

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 be able to provide redundant resources, for example, by splitting themselves into multiple resource block sets.

FIG5 illustrates a schematic diagram of an exemplary division of resource block sets in sidelink communications 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. Among them, it is assumed that RBS1 carries PSSCH resources. After the first node in the sidelink communication transmits PSSCH to the second node, it is assumed that in time slot 6, feedback for the received PSSCH, i.e., PSFCH resources, will be carried in the corresponding RBS1. However, due to the LBT failure in the RBS1, at this time, the PSFCH resources are 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., 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.

From this, the following scheme can be summarized.

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, and 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, 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.

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.

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).

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.

As a result, efficient scheduling of PSFCH across resource block sets is achieved, improving the efficiency and reliability of side link communications.

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.

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

According to some embodiments of the present disclosure, the SCI signaling may indicate a time slot for transmitting the PSFCH.

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 can be understood 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, which depends on the setting and implementation of the specific protocol, and the present disclosure does not impose any limitation on this.

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

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

In carrier aggregation, Mode 2 is a common carrier aggregation method. In Mode 2, licensed carriers and unlicensed carriers can be used simultaneously to provide a higher overall data transmission rate.

In carrier aggregation, licensed carriers and unlicensed carriers usually have different spectrum widths and transmission capabilities. Licensed carriers usually have wider spectrum bandwidths and higher transmission rates, while unlicensed carriers are relatively narrow and limited. Therefore, when performing carrier aggregation, you may face the problem of unbalanced load distribution between licensed and unlicensed carriers. This imbalance may cause some carriers to be overloaded while other carriers are underloaded. Overloaded carriers may experience performance degradation, increased transmission delays, or unstable connections, while underloaded carriers are not fully utilized to their potential.

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.

In this regard, the present disclosure provides the following solution. When the UE is configured with carrier aggregation of mode 2 licensed carriers 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.

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, which is performed by a first node, including: Operation 610: transmitting sidelink control information SCI signaling by the first node in the sidelink communication to a second node in the sidelink communication, wherein the SCI The signaling is carried by the first carrier, wherein the SCI signaling includes a channel occupancy time COT on the second carrier and a cell index or a carrier index associated with the second carrier.

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.

FIG6B illustrates a schematic diagram of an exemplary signaling interaction between a first node and a second node in side link communication according to some embodiments of the present disclosure.

According to some embodiments of the present disclosure, as shown in Fig. 6B, a sidelink communication method is provided. The method may be performed by a first node, and includes: transmitting sidelink control information SCI signaling by the first node in the sidelink communication 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.

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.

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

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

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.

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.

LBT failure indication enhancement

On NR-U, the UE's uplink transmission is based on the uplink grant (UL grant) sent by the base station (e.g. gNB). However, before sending, the UE needs to perform LBT. If the UE fails LBT on a resource block set (RB set) in the physical layer L1, all RB sets on the entire time slot cannot be transmitted, because the base station (e.g. gNB) schedules a transport block (TB) on the entire time slot and cannot determine whether the UE has transmitted on the RB set with LBT failure.

The same principle applies to SL-U. When a UE fails an LBT on a certain RB set of the physical layer L1, it cannot use other RB sets of the time slot. This is because the side link control information SCI has indicated all RB sets of the time slot, so the Rx UE cannot receive all RB sets and therefore cannot send.

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).

Option 1: PHY signaling indicates that RB set is not available.

One or more indicator bits can be added to the SCI signaling (e.g., SCI 2A/B) to indicate the index of some unavailable RB set(s).

According to some embodiments of the present disclosure, a sidelink communication method is provided. The method can be performed by a first node, and includes: preparing by the first node in the sidelink communication (for example, in some cases, the first node configures itself; of course, in some other cases, it is not excluded that the first node reports the configuration requirement to the network side (for example, the core network CN) and the network side transmits the configured signaling back to the first node, etc.) control signaling related to the sidelink communication; the first node transmits the control signaling to the second node in the sidelink communication to indicate that the listen-before-talk LBT fails.

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.

Option 2: When the MAC layer determines that consecutive LBT failures have occurred, it indicates that the RB set is unavailable through MAC CE.

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

Since the time slots of the entire carrier are not available, other carriers can be used to send MAC CE for indication.

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.

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

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, which is performed by a first node, including: operation 710: the first node in the sidelink communication prepares control signaling related to the sidelink communication; operation 712: the first node transmits the control signaling to the second node in the sidelink communication to indicate that the listen-before-talk LBT fails; 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.

Through the above embodiments, the present disclosure solves the problem that when part of the carriers of the RB set fail, the RB set on the entire time slot is unavailable, causing waste.

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. According to some embodiments of the present disclosure, the MAC CE also includes an index of a carrier associated with the RB set.

FIG7B illustrates a schematic diagram of a bitmap of a MAC CE according to some embodiments of the present disclosure. According to some embodiments of the present disclosure, the bitmap extension of the MAC CE includes, for example, the following extension methods: Each bit in the bitmap is used to indicate whether LBT occurs for the corresponding RB set index (RB set index). Each bit in the bitmap corresponds to the index of each RB set that fails to be available due to the LBT failure. The bits include, for example, C0, C1, C2, C3, C4, C5, C6, and C7.

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 from the first node to the second node together with the LBT failure indication message.

According to some embodiments of the present disclosure, the method further includes: the first node transmits an LBT failure cancellation message to the second node, and the LBT failure cancellation message includes at least one of a carrier index and an RB set index. This can solve the following technical problem: after continuous LBT failures occur in the SL, the TX UE will not use this block of resources, which causes waste in the long run.

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 the carrier corresponding to at least one of the carrier index and the RB set index.

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

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

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.

Through the above embodiments, the present disclosure solves the technical problem of how to indicate resource availability in a side link, thereby facilitating communication decisions and adjustments between nodes in side link communications.

LBT failed to cancel

LBT failure recovery mainly depends on resource reselection. And during resource reselection, the RB set where C-LBT occurs needs to be excluded. In addition, there are differences in LBT failure cancellation on the Uu interface and the side link. The Uu interface relies on a successful random access, while the LBT failure cancellation on the side link mainly relies on the upper layer resetting the MAC and reconfiguring parameters, and there is no interaction between the two peer UEs.

However, in mode 2 on the side link, since the resources are selected by the node (such as Tx UE, etc.), after the Tx UE receives the LBT failure indication, the Tx UE will never use the resources where the LBT failure occurred. The Tx UE will perform resource reselection to recover from the LBT failure.

It can be seen that the Uu interface can recover LBT through random access, but there is no random access process on the side link. Therefore, in order to solve the problem that the Tx UE on the side link no longer uses the resources where the LBT failure occurred, the present disclosure provides the following solution.

According to some embodiments of the present disclosure, as shown in FIG. 7C, the method may further include: transmitting, by the first node, an LBT failure cancellation message to the second node, wherein the LBT failure cancellation message includes a carrier index and a resource block set RB set index. At least one.

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 the carrier corresponding to at least one of the carrier index and the RB set index.

Thus, by introducing the LBT failure cancel message, it is possible to indicate to the peer UE that the previously unavailable resources 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 for which an LBT failure has occurred can be used again. It should be noted here that the LBT failure is defined at the RB set granularity. That is, the LBT failure is expressed in the name of the RB set, rather than in the name of the carrier, and when it is mentioned that an LBT failure has occurred, it means that an LBT failure has occurred in a certain RB set.

Through the above embodiments, the present disclosure solves the technical problem of how to indicate the resource availability in the side link, thereby facilitating communication decision-making and adjustment between nodes in the side link communication. Furthermore, by introducing the LBT failure cancellation message, the carrier resources that have been discarded can be reused, thereby improving resource utilization and the efficiency of side link communication.

What is described herein is an unlicensed spectrum re-carrier aggregation enhancement method in sidelink communication, which is applicable to a first node and communication between the first node and a second node. However, these inventive concepts, methods, devices, equipment, computer-readable storage media, chips, and computer program products are not limited to sidelink communication, but can also be extended to other communication scenarios to achieve the same technical benefits and effects.

In these scalable communication scenarios, the first node and/or the second node may be a user equipment (UE), a base station (such as a gNB, eNodeB, a transmission reception point (TRP), a NodeB or a WIFI access point for next generation communications, etc.), or an entity such as a network element. User equipment (UE) refers to a device used for communication at the user end, such as a mobile phone, and may also be referred to as a terminal, a mobile station, or a mobile terminal. UE may be a variety of devices, including but not limited to mobile phones, tablet computers, 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, etc.

In addition, UE and base station can be deployed in different environments, including but not limited to indoors, outdoors, handheld devices, vehicle-mounted devices, or even deployed on water, in the air, on airplanes, drones, or satellites.

Therefore, although the present invention describes methods and devices for sidelink communication, etc., the inventive concepts and technologies contained therein can be extended to other communication scenarios, and it is expected that the same technical benefits and effects can be achieved. It is easy to understand that these inventive concepts have wide applicability and scalability, whether in communication between different types of base stations and user equipment, or in communication in different deployment environments.

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

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.

The present disclosure describes an example of communication between a terminal and a network element component in a network architecture in the above embodiments, which is mainly for illustrative purposes and not restrictive.

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 an alternative method. Generally, any of the components, modules, methods, and operations described herein can be implemented using software, firmware, hardware (e.g., fixed logic circuits), 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 of a computer processing system, and implementations 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.

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

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

According to an example embodiment, referring to FIG8 , there is provided a sidelink communication method, performed by a first node, comprising:

Step S801, the first node in the sidelink communication configures the sidelink reconfiguration message to have a carrier aggregation indicator, and the carrier aggregation indicator indicates a primary carrier in the sidelink carrier aggregation SL CA;

Step S802, transmitting the side link reconfiguration message to the second node in the side link communication by the first node; and

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.

According to an example embodiment, referring to FIG9 , there is provided a sidelink communication method, performed by a first node, comprising:

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

According to an example embodiment, referring to FIG10 , there is provided a sidelink communication method, performed by a first node, comprising:

Step S1001, the first node in the sidelink communication configures sidelink control information SCI signaling, the SCI signaling indicating resources used for the second node in the sidelink communication to transmit a physical sidelink feedback channel PSFCH,

Among them, the PSFCH (feedback is the resources of the channel PSFCH, why is PSFCH explained here) is provided by the second node The transmission is based on receiving a physical sidelink shared channel PSSCH transmitted by the first node.

According to an example embodiment, referring to FIG11 , there is provided a sidelink communication method, performed by a first node, comprising:

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.

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

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

Step S1201, the first node in the sidelink communication prepares control signaling related to the sidelink communication;

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

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

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

According to an example embodiment, a device in a sidelink communication system is provided, the device being 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.

According to an example embodiment, a chip is provided, the chip 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-mentioned embodiments, examples, or example embodiments.

According to an example embodiment, a computer-readable storage medium is provided 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 example embodiments.

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.

FIG. 13 is a block diagram of an example system 700 for wireless communication according to an embodiment of the present disclosure. The embodiments described herein may be implemented into a system using any appropriately configured hardware and/or software. FIG. 13 illustrates a system 700, including a radio frequency (RF) circuit 710, a baseband circuit 720, a processing unit 730, a memory/storage 740, a display 750, a camera 760, a sensor 770, and an input/output (I/O) interface 780, coupled to each other as shown.

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 connected to a memory/storage device. The system 700 is coupled to a processor 710 and is configured to execute instructions stored in a memory/storage device to enable various applications and/or operating systems running on the system. The RF circuit 710, the baseband circuit 720, the processing unit 730, the memory/storage device 740, the display 750, the camera 760, the sensor 770, and the I/O interface 780 are well-known components in the system 700, such as, but not limited to, a laptop computing device, a tablet computing device, a netbook, an ultra-extreme notebook, a smart phone, etc. In addition, instructions as software products can be stored in a readable storage medium in a computer. The software product in the computer is stored in a storage medium, including multiple commands for a computing device (such as a personal computer, a server, or a network device) to run 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 code.

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

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

Claims (31)

A side link 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 a sidelink carrier aggregation; and 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. The method of claim 1, wherein the carrier aggregation indicator comprises at least one of a cell ID or a carrier index. The method according to claim 1 or 2, wherein the sidelink carrier aggregation comprises: The licensed carrier performs carrier aggregation with another licensed carrier. Carrier aggregation of licensed carriers and unlicensed carriers, or An unlicensed carrier performs carrier aggregation with another unlicensed carrier. 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). The method according to claim 1 or 2, wherein the sending of the carrier aggregation indicator comprises: sending a sidelink reconfiguration message, the sidelink reconfiguration message comprising the carrier aggregation indicator. A resource reselection method in side link communication, comprising: Configure one or more first listen-before-send LBT failure counters under carrier aggregation CA, where the first LBT failure counter is configured to record the number of LBT failures occurring under the CA, and the first LBT failure counter corresponds to a first threshold; 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 When the value of the first LBT failure counter reaches the first threshold, resource reselection is performed. 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 occurring on the plurality of 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, the resource reselection is performed for the any carrier. The method according to claim 6, wherein The one or more first LBT failure counters are configured to record a combined number of LBT failures occurring on a plurality of 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, the resource reselection is performed on a carrier having a larger number of LBT failures among the multiple carriers. The method according to claim 6, wherein The first LBT failure counter is configured to record the number of LBT failures occurring on an 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, the resource reselection is performed for the unlicensed carrier. A carrier reselection method in side link communication, comprising: receiving a listen-before-send LBT failure message for a target carrier; and In response to the LBT failure message matching a preset condition, performing carrier reselection for the target carrier; The preset conditions include: The first LBT failure occurs on the target carrier; or Consecutive LBT failures occur on the target carrier. A sidelink communication method, performed by a first node, comprising: 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, The PSFCH resource is transmitted by the second node based on receiving a physical side link shared channel PSSCH transmitted by the first node; The resources used for the PSFCH are different from the resources used for the PSSCH. The method of claim 11, wherein the SCI signaling is transmitted on a first carrier. The method according to claim 12, wherein 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. The method according to claim 13, wherein, in the case that a carrier originally scheduled to carry the PSFCH fails in continuous listen-before-talk (LBT), the second node schedules the second carrier to carry the PSFCH. 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 a redundant resource. The method according to claim 15, wherein the RB set is indication information of redundant resources of the PSFCH. The method according to claim 15 or 16, wherein the SCI signaling indicates a time slot in which the PSFCH is transmitted. A sidelink communication method, performed by a first node, comprising: 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, The SCI signaling includes a channel occupancy time COT on the second carrier and a cell index or a carrier index associated with the second carrier. 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. The method according to claim 18 or 19, wherein the first carrier is a licensed carrier and the second carrier is an unlicensed carrier. 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). A sidelink communication method, performed by a first node, comprising: preparing, by the first node in the sidelink communication, control signaling associated with the sidelink communication; The control signaling is transmitted by the first node to the second node in the sidelink communication to indicate that the listen-before-talk (LBT) fails; The control signaling is side link control information SCI signaling, and the SCI signaling includes the index of the resource block set RB set that is unavailable due to the LBT failure. 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. A method according to claim 23, wherein the MAC CE also includes an index of a carrier associated with the RB set. The method according to any one of claims 22 to 24, wherein the control signaling is included in an LBT failure indication message. The method according to any one of claims 22 to 25, wherein the control signaling is transmitted from the first node to the second node together with the LBT failure indication message. The method according to any one of claims 22 to 26, further comprising: An LBT failure cancellation message is transmitted by the first node to the second node, and the LBT failure cancellation message includes at least one of a carrier index and an RB set index. The method according to claim 27, wherein the LBT failure cancellation message is transmitted by the first node based on performing LBT recovery on the carrier corresponding to at least one of the carrier index and the RB set index. A device in a sidelink communication system, the device being configured to perform the method according to any one of claims 1 to 28. A chip, comprising: a processor, configured to call and run a computer program from a memory, so that a device equipped with the chip executes a method according to any one of claims 1 to 28. A computer-readable storage medium, wherein the storage medium is used to store a computer program, wherein the computer program causes a computer to execute the method according to any one of claims 1 to 28.