A power saving method for NR-V2X multicast communication

Abstract

The present application provides a method for power saving in NR-V2X multicast communication, which uses the zone ID and the destination ID as control parameters, and all group members use them as reference points, and statically or dynamically control the DRX cycle and the UE's active interval to achieve power saving. The two control parameters have different functions, the former is used for multicast based on the communication range, and the latter is used for multicast with a destination ID indicated by the high layer. The method can achieve energy saving, improve reliability and reduce latency.

Description

Technical Field

[0001] The present application relates to a communication method, and more particularly to a method for saving power and reducing side link transmission resource conflicts during transmission for NR-V2X multicast communication. Background Art

[0002] In the field of communications, there are currently two power management mechanisms, one is the idle mode mechanism (Idle Mode) and the other is the discontinuous reception mechanism (Discontinuous Reception, DRX).

[0003] When a user equipment (UE) enters the idle mode mechanism, the UE is no longer actively connected to a base station (such as a 4G base station eNB), although the network is still able to track the UE through a paging mechanism. The idle mode allows the UE to remain in a very low power consumption mode because the UE only needs to perform very limited functions in this mode.

[0004] In DRX mode, the UE can save power consumption by allowing the UE to cut off power at predetermined time intervals as instructed by the eNB. DRX provides significant benefits in both resource utilization and energy saving, but requires a trade-off between energy saving and transmission delay. Therefore, in order to balance battery saving and transmission delay, LTE (Long Term Evolution) supports short DRX and long DRX mechanisms, and allows the UE to be configured with two DRX cycles (DRX Cycle), namely short DRX cycle and long DRX cycle. The UE is activated to receive or send data packets only for a period of time within the cycle.

[0005] In LTE-V2X (Long Term Evolution Vehicle-to-Everything), although DRX cycles are still involved, the energy-saving mechanism is quite unique. In the Uu link, the UE does not receive the downlink channel during DRX for the purpose of saving battery. However, in the sidelink, V2X transmission must be sensed before transmission to reduce random resource selection conflicts and thus improve the packet reception ratio (PRR) performance. To this end, LTE-V2X introduces a partial sensing mechanism that allows the UE to perform sensing operations within a specific sensing window and within a limited time. Using the partial sensing mechanism, each UE is configured or pre-configured (i.e., (pre) configured) with UE-specific parameters related to sensing. For example, if partial sensing is configured for a pedestrian UE, then within the sensing window (e.g., 1000 subframes), before performing partial sensing, the UE needs to obtain two parameters: one is used to indicate the minimum number of subframes included in possible candidate resources (expressed as minNumCandidateSF), and the other is used to indicate the sensing subframes when certain subframes are considered as candidate resources (expressed as gap Candidate Sensing).

[0006] In traditional LTE-V2X, the sensing and resource selection process is designed for periodic data packet broadcast services. Sensing and reception are performed in a periodic triggered manner, and DRX is effectively configured in K DRX cycles within the sensing window, while the transmission process uses a periodic or event triggered manner depending on the service type. Once the UE senses in a subframe, it may not need to decode the data packet on the physical sidelink (Sidelink) data channel (PSSCH: Physical Sidelink Shared Channel), but once the UE decodes the data packet on the PSSCH, it must pre-sense or decode the SCI (Sidelink Control Information) on the physical sidelink control channel (PSCCH: Physical Sidelink Control Channel) in the subframe. In other words, the UE can only perform reception or transmission when it is in sensing mode. Whether the UE is to perform sensing mode in the kth DRX cycle depends on the (pre) configured sequence model q K = {q 1 ,q 2 ,…,q K}. This means that if q k=1, the UE shall perform sensing mode in the kth DRX cycle, otherwise, the UE shall remain in sleep mode.

[0007] Figure 1 The partial sensing procedure of LTE-V2X is described in detail, where the sensing subset is (pre-)configured for the UE to be activated, the UE sensing interval X=5, the number of DRX cycles K=10, and the sequence pattern q K ={1100100001} to effectively formulate the DRX cycle period. However, this partial sensing mechanism is only applicable to broadcast communications with periodic packet traffic.

[0008] NR-V2X (New Radio Vehicle-to-Everything) has a wide range of applications. It supports more than 30 use cases, including unicast, groupcast, and broadcast communications. For such a complex application area, the biggest challenge in achieving energy saving is how to balance multicast performance and power consumption. It is generally believed that a single DRX parameter set is not enough to meet the services of different communication types. For example, in the main use case multicast, there are vehicle platooning, automated cooperative driving, sensor information sharing, remote driving, etc.; they have different performance requirements, such as reliability (such as packet reception ratio, PRR), coverage (such as communication range, communication range) and latency. Therefore, when achieving multicast power saving, the biggest challenge is to ensure that all group members are in the same transmission time slot to sense the channel and receive or send data packets.

[0009] Since the use cases in NR-V2X are more complex, especially for multicast communication, the energy-saving mechanism of traditional LTE-V2X will not be effectively used. In multicast communication, when the multicast member UEs randomly sleep and wake up during the DRX cycle, there is a problem that some member UEs cannot communicate with each other, which will seriously degrade the performance of PRR. There are two types of multicast: the first is based on the communication range, which is composed of UEs located in the communication range; the second is composed of multicast members with the same dedicated target ID (also called target L2 ID, Destination ID or Destination L2 ID), and has a high-level determination and is delivered to each multicast member in advance.

[0010] Figure 2 The worst case of partial sensing in multicast is given, where five receiving Rx UEs (Receive UEs) randomly sleep and wake up in the DRX cycle (e.g. 100ms), unable to receive data packets sent from Tx UEs (Transmit UEs), resulting in a PRR of zero. If the multicast UEs are forced to sleep and wake up at the same time, although all multicast UEs are able to receive data packets, the optional resources for transmission by different multicast UEs are limited, resulting in resource conflicts between Tx UEs. Summary of the invention

[0011] In response to the energy saving and resource conflict problems existing in the prior art, the present application provides a method for saving power and reducing side link transmission resource conflicts during transmission for NR-V2X multicast communication.

[0012] The present application provides a method for power saving and reducing Tx UE transmission resource conflicts in NR-V2X multicast communication, wherein the multicast is implemented based on a dedicated target L2 ID determined by a high layer, different multicasts have different target L2 IDs, and all UEs in the jth multicast know in advance the dedicated target L2 ID associated with the multicast service and mark it as ID j , where j = 0, 1, …, J-1, and J is the maximum number of multicasts allowed by the multicast service.

[0013] Preferably, the member UE in the jth multicast is in the kth DRX cycle period, the nth k,j The time slot (i.e., Slot or time) is activated and receives or sends data packets, n k,j Expressed as

[0014] n k,j =(ID j +Δ k )mod N k ,

[0015] Among them, N k is the number of time slots in the kth DRX cycle, i.e., the cycle length, expressed in time slots or time (ms), Δ k is the mapping offset in the kth DRX cycle, 0≤Δ k <N k , k = 1, 2, ..., K, K is the number of DRX cycles.

[0016] It is worth noting that, in order to save power and reduce the conflict of sidelink transmission resources in different multicasts, the present invention effectively uses the target L2 ID to distinguish the activation time of Tx UE between different multicasts in the time domain.

[0017] More effectively, at different times in the DRX cycle, in order to reduce the Tx UE transmission resource collision in multicast, the present invention adopts a mapping offset Δ k The value, that is, the activation time of the Tx UE in the kth DRX cycle depends not only on the target L2ID, but also on the mapping offset Δ k Therefore, the probability of resource conflict between Tx UEs is greatly reduced, and power saving is also achieved. Optionally, the jth member UE in the kth DRX cycle and the rth member UE in the rth DRX cycle are k,j resource pools are activated, r k,j Expressed as

[0018] r k,j =(ID j +Δ' k )mod M R ,

[0019] Among them, M R is the number of resource pools that the UE is (pre)configured with, Δ' k is the mapping offset in the kth DRX cycle, 0≤Δ' k <M R , k = 1, 2, ..., K, K is the number of DRX cycles.

[0020] Preferably, all UEs associated with the jth multicast have 2Y k,j +1 time slot for sensing.

[0021] More preferably, the sensing interval of each multicast UE is kept substantially constant, Y k,j Simplified to Y j .

[0022] In a preferred embodiment, a continuous slot sensing method is used to sense the state S of the jth multicast service in the nth slot in the kth DRX cycle. k,j (n) (Pre)Configured

[0023]

[0024] Where n=0,1,…,N k -1, Y k,j It is the (pre-)configuration parameter of the UE sensing interval in the jth multicast in the kth DRX cycle.

[0025] Preferably, S k,j (n)=1, the UE associated with the j-th multicast indicated by the target L2 ID is activated for sensing in the n-th time slot in the k-th DRX cycle, otherwise the UE remains in sleep mode.

[0026] In another preferred embodiment, a distributed slot sensing method is used, in the kth DRX cycle, k,j N timeslots associated with the jth multicast service k The sensing state S of the time slot k,j (n k,j ) can be (pre)configured as

[0027] S k,j (n k,j )={S k,j (0), S k,j (1),…,S k,j (N k -1),}

[0028] like:

[0029] Preferably, S k,j (n k,j ) is equal to 1, which is consistent with the target L2 ID (i.e. ID j ) indicates that the j-th groupcast associated UE is activated for sensing in the n-th time slot in the k-th DRX cycle, otherwise the UE remains in sleep mode.

[0030] Preferably, the total slot sensing state in the kth DRX cycle period Through the set S k,j (n k,j ), that is,

[0031]

[0032] Preferably, according to the target L2 ID indicated by the higher layer, the UE may also be controlled to perform sensing in part of the resource pools, thereby achieving energy saving effect.

[0033] Preferably, the member UE in the jth multicast is activated in the kth DRX cycle and the rk,jth resource pool, where rk,j can be expressed as

[0034] r k,j =(ID j +Δ' k )mod M R , where M R is the number of resource pools that the UE is (pre)configured with, Δ' k is the mapping offset in the kth DRX cycle, 0≤Δ' k <M R .

[0035] Preferably, a resource pool is defined as a subset of time slots and frequency resource blocks available for sidelink transmission or reception. The resource pool in the time domain is indicated by a bitmap and is repeated at a certain interval. The repetition time interval of the resource pool can be assumed to be the same as the DRX cycle, or an integer multiple of each other.

[0036] More preferably, all UEs associated with the groupcast may combine time slot and resource pool associated parameters to perform more efficient energy saving sensing in different DRX cycle periods.

[0037] In the present invention, the destination L2 ID is used as a control parameter to determine the activation time (ie, Active time) in the DRX cycle; the activation resource pool in the DRX cycle is determined according to the destination L2 ID; and the activation sensing window in the DRX cycle is determined according to the destination L2 ID.

[0038] The present invention achieves power saving and resource conflict reduction effects by controlling the target L2 ID parameter mechanism, and can ensure the overall performance in terms of energy saving, transmission reliability and transmission delay. The energy saving mechanism of the present invention is effective for multicast. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is an example of a partial sensing procedure for LTE-V2X, where Y=5, K=10, q K ={1100100001}.

[0040] Figure 2 Partial sensing example for random sleep and wakeup for multicast communication.

[0041] Figure 3 Dynamic mapping offset Δ KExample.

[0042] Figure 4 It is a partial sensing method based on the continuous time slots of the target L2 ID.

[0043] Figure 5 This is an example of partial sensing in a distributed time slot sensing manner based on a target L2 ID.

[0044] Figure 6 is an example of partial resource pool sensing based on target L2 ID. DETAILED DESCRIPTION

[0045] As we all know, there are two types of multicast: the first type is based on the communication range, which consists of UEs within the communication range; the second type is composed of multicast members with the same dedicated destination L2 ID, which is determined by the upper layer and passed to each multicast member in advance.

[0046] In the first type of multicast, the Tx UE sends its own location and the communication range associated with the data packet. All Rx UEs calculate the distance to the Tx UE, compare the communication range, and then determine whether they are members of the multicast. In the second type of multicast, the application layer determines the target L2 ID, passes it to the 3GPP layer in advance, and notifies each multicast member. Whenever a multicast data packet is sent, the upper layer passes the target L2 ID to the MAC layer together with the data packet, and the Tx UE sends the target L2 ID to all UEs together with the data packet. Then, the Rx UE compares the target L2 ID it has in advance with the target L2 ID received with the data packet. If they are consistent, the data packet is a multicast data packet of the target L2 ID.

[0047] Generally, for a specific service, V2X UE will be allowed to support multiple unicast connections or multiple broadcast connections at the same time. Therefore, the target L2 IDs of different multicasts are different; some multicast target L2 IDs can be generated in the AS (Access Stratum) layer, while some multicast target L2 IDs can come from the upper layer (such as the V2X application layer).

[0048] Different types of multicast require different sidelink control information (SCI: Sidelink Control Information). For multicast based on communication range, the Tx UE needs to transmit its location information and communication range in the SCI, so that each Rx UE can determine whether the Rx UE belongs to the multicast range through the location of the Tx UE and the Rx UE itself. For multicast based on target L2 ID, the Tx UE needs to send the target L2 ID associated with the multicast in the SCI, so that each Rx UE can determine whether it belongs to the multicast range. Once the Rx UE determines that it belongs to the multicast range (for any type of multicast), the Rx UE will start the HARQ process to decide whether to feedback ACK (Acknowledgement) or NACK (Negative Acknowledgement).

[0049] For multicast based on target L2 ID, this application introduces parameters related to the target L2 ID to solve the problem of power saving and reducing resource conflicts.

[0050] Example 1

[0051] If the mapping offset Δ is used in different DRX cycles k If the value is fixed, the probability of resource conflict between Tx UEs may increase. This is because the resources or resource candidates selected by UEs in the same sensing, transmission and reception intervals will be the same in the time domain and frequency domain, thus reducing the freedom of resource selection and affecting the overall performance of NR-V2X.

[0052] Here, in addition to distinguishing the activation time of different multicast Tx UEs in the time domain by using the target L2 ID parameter in the DRX cycle, this embodiment also configures different mapping offset values ​​Δ in the DRX cycle more effectively. k , Tx UE can be activated at different times in different DRX cycles to reduce the probability of UE selecting resource conflicts.

[0053] In order to reduce the possibility of resource conflicts, this embodiment considers the (pre)configured sequence model Δ K ={Δ 1 ,Δ 2 ,…,Δ K}, change the mapping offset value Δ in different DRX cycles k . Figure 3 An example of dynamic mapping shift within a sensing window is shown with configurable parameters N=100, K=10, and configuration sequence model Δ K ={0,10,…,90}, where K is the number of DRX cycles.

[0054] Example 2

[0055] Multicast services can be implemented based on a dedicated target L2 ID determined by the higher layer; that is, different multicasts have different target L2 IDs. Therefore, DRX-based energy saving can also effectively rely on the target L2 ID information. By obtaining the LSB (Least Significant Bit) of the target L2ID, each UE can determine the UE active time (Active Time) and sensing interval (Sensing Interval) based on the (pre-)configured values ​​within the DRX cycle.

[0056] Assume that all UEs in the jth multicast know in advance the dedicated target L2 ID associated with the multicast service, marking it as ID j , where j = 0, 1, ..., J-1, J is the maximum number of multicasts allowed by the multicast service. This is because NR-V2X allows UE to support multiple multicast group services at the same time. Therefore, according to the target L2 ID (i.e. ID j ), the member UE in the jth multicast should be in the kth DRX cycle, the nth k,j The time slot is activated and receives or sends data packets. k,j It can be expressed as

[0057] n k,j =(ID j +Δ k )mod N k ,

[0058] Among them, N k is the length of the kth DRX cycle in the time slot, Δ k is the mapping offset in the kth DRX cycle (usually an integer), which mainly plays a pseudo-randomization role, 0≤Δ k <N k , k = 1, 2, ..., K, K is the number of DRX cycles.

[0059] It is worth noting that, in order to save power and reduce the conflict of sidelink transmission resources in different multicasts, the present invention effectively uses the target L2 ID to distinguish the active time (Active Time) of Tx UE between different multicasts in the time domain.

[0060] More effectively, at different times in the DRX cycle, in order to reduce the collision of Tx UE transmission resources in multicast, this embodiment adopts a mapping offset Δ k The value, that is, the activation time of the Tx UE in the kth DRX cycle depends not only on the target L2 ID, but also on the mapping offset Δ kTherefore, the probability of resource conflict between Tx UEs is greatly reduced, while also achieving power saving. k For a description of the specific embodiment related to the value, please refer to Example 1.

[0061] Example 3

[0062] For both transmitting and receiving UEs, only a single slot in the DRX cycle needs to be specified. However, for sensing and resource selection purposes, multiple slots are required to ensure that sufficient resources are available in the set of candidate slots. Therefore, in this case, all UEs associated with the jth multicast need to be in 2Y slots in the kth DRX cycle. k,j +1 time slot. Since the services in each multicast are generally similar, the sensing interval of each multicast UE can be kept basically constant. In other words, parameter Y k,j It can be simplified to Y j .

[0063] In addition, the sensing time slots may be (pre)configured based on a continuous time slot sensing method or a distributed time slot sensing method. If the continuous time slot sensing method is used, for example, the sensing state S of the jth multicast service in the nth time slot of the kth DRX cycle is set to k,j (n) (Pre)Configured

[0064]

[0065] Where n=0,1,…,N k -1, Y k,j It is the (pre-)configuration parameter of the UE sensing interval in the jth multicast in the kth DRX cycle.

[0066] It should be noted that if S k,j (n) = 1, the UE associated with the jth groupcast indicated by the target L2 ID should be activated for sensing in the nth time slot in the kth DRX cycle, otherwise the UE should remain in sleep mode. In each DRX cycle, the sensing time slots of each UE between different groupcasts may overlap, which helps to reduce the overall UE sensing interval within the DRX cycle, but will not affect the overall performance.

[0067] As an example, assume that the UE interval is based only on multicast traffic and has nothing to do with the index of the DRX cycle. Therefore, if the configurable parameters N = 16, K = 3, J = 2, Δ k =0, {ID 0 ID 1}={43 20},{Y 0 Y1}={1 2}, according to ID j value, we can deduce n k,j

[0068]

[0069] With these configuration parameters and derived values, Figure 4 An example is given of a partial sensing method based on consecutive time slots of a target L2 ID.

[0070] If a distributed time slot sensing method is used, for example, in the kth DRX cycle, k,j N timeslots associated with the jth multicast service k The sensing state S of the time slot k,j (n k,j ) can be (pre)configured as

[0071] S k,j (n k,j )={S k,j (0), S k,j (1),…,S k,j (N k -1),}

[0072] For example:

[0073]

[0074] It should be noted that if S k,j (n k,j ) k,j (n) is equal to 1, then the target L2 ID (i.e. ID j ) indicates that the UE associated with the jth multicast should be activated for sensing in the nth time slot in the kth DRX cycle, otherwise the UE should remain in sleep mode. The total time slots represented by the set S k,j (n k,j ) is calculated by the union of

[0075]

[0076] For example, assuming N=16, K=3, J=2, {ID 0 ID 1}={43 20} and {Y 0 Y 1}={1 2}, we can map S k,j (n k,j ) for (pre)configuration

[0077]

[0078] Since the UE sensing intervals of these two multicasts partially overlap, the union of these two multicasts can be described as

[0079]

[0080] Figure 5 An example of partial sensing based on target L2 ID and distributed time slot sensing is shown in FIG. 1 , in which two multicasts jointly activate the 13th time slot, thereby reducing the total number of sensing time slots.

[0081] It is worth noting that the parameter Y k,j Should not be set too large, the larger the Y k,j More sensing time is required, resulting in greater power consumption. k,j The value depends on the priority of the multicast service. In addition, the more overlapping sensing time slots, the better the energy saving effect. However, overlapping sensing time slots may reduce the freedom of resource selection in the candidate time slot set and cause resource selection conflicts between Tx UEs.

[0082] Assume that each UE can join at most J multicasts at the same time. If the UE wants to further reduce power consumption, it is necessary to limit the number of multicasts sensed by the UE. lim Multicast, where J lim ≤ J. Which multicast the UE joins for sensing will depend on the following factors:

[0083] · The priority of the multicast service, or

[0084] The freshness of the target L2 ID passed from higher layers (i.e., how long the multicast service has lasted), or

[0085] The number of transmissions associated with the target L2 ID multicast, or

[0086] The above comprehensive factors.

[0087] Example 4

[0088] According to the target L2 ID (ie ID j ), the member UE in the jth multicast should be in the kth DRX cycle, the rth k,j resource pool is activated. k,j It can be expressed as

[0089] r k,j =(ID j +Δ' k )mod M R ,

[0090] Among them, MR is the number of resource pools that the UE is (pre)configured with, Δ' k is the mapping offset in the kth DRX cycle, 0≤Δ' k <M R , k = 1, 2, ..., K, K is the number of DRX cycles.

[0091] More effectively, at different times in the DRX cycle, in order to reduce the collision of Tx UE transmission resources in multicast, this embodiment adopts a mapping offset Δ' k Value, that is, the activation of the UE resource pool in the kth DRX cycle depends not only on the target L2 ID, but also on the mapping offset Δ' k Therefore, the probability of resource conflict between Tx UEs is greatly reduced, while also achieving power saving. k For a description of the specific embodiment related to the value, please refer to Example 1.

[0092] It should be noted that a resource pool is defined as a subset of time slots and frequency resource blocks available for sidelink transmission or reception. The resource pool in the time domain is indicated by a bitmap and repeats at a certain interval. We can assume that the repetition time interval of the resource pool is the same as the DRX cycle, or is an integer multiple of each other.

[0093] Therefore, the Tx UE associated with the jth group selects the rth k,j In the kth DRX cycle, all Rx UEs associated with the jth group only need to access the rth group. k,j resource pools, and the Tx UE performs sensing in all (or part) time slots in the kth DRX cycle. Note that considering sensing in part of the time slots is mainly to combine the resource pool sensing mechanism with the aforementioned part of the time slot sensing mechanism, thereby achieving a better energy saving effect.

[0094] As an example, the UE only needs to sense the corresponding resource pool. For simplicity, we assume that the repetition time interval of the resource pool is the same as the DRX cycle, and the sensing of the resource pool is based on M R =3(by R 0 , R 1 and R 2 Resource pools with different frequencies), K = 3, J = 2, {Δ 1 Δ 2 Δ 3}={0 2 1}, and {ID 0 ID 1 Here, we can derive the resource pool index

[0095] and

[0096] Using these configuration parameters and the derived resource pool index, resource pool sensing based on multicast target L2 ID is performed as follows: Figure 6 shown.

[0097] Generally, the NR-V2X system allows UE to support multiple different services at the same time, such as multicast services based on target L2 ID and multicast services based on communication range. Therefore, all the mechanisms proposed above can fully participate in the decision of UE activation time, resource pool activation and sensing interval in each DRX cycle, so as to more effectively realize DRX transmission / reception and partial sensing of NR-V2X, and achieve power saving and reduce side link transmission resource conflicts during transmission.

[0098] The above describes the specific embodiments of the present invention in detail by taking multicast as an example, but it is only an example, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modification and substitution of the present invention also falls within the scope of the present invention. Therefore, the equal transformation and modification made without departing from the spirit and scope of the present invention should be included in the scope of the present invention.

Claims

1. A power saving method for NR-V2X multicast communication, It is characterized in that Multicast is implemented based on a dedicated target ID determined by the higher layer. Different multicasts have different target L2 IDs. All UEs in the jth multicast know in advance the dedicated target ID associated with the multicast service and mark it as ID j , where j = 0, 1, ..., J-1, J is the maximum number of multicasts allowed by the multicast service; where: The member UEs in the jth multicast group receive the kth DRX cycle and the nth k,j is activated in time slots, n k,j Expressed as n k,j =(ID j +D k )mod N k , Or, the member UE in the jth multicast is in the kth DRX cycle, the rth k,j resource pools are activated, represented by r k,j =(ID j +Δ' k )mod M R ; Among them, N k is the length of the kth DRX cycle in the time slot, M R is the number of resource pools configured for the UE, Δ k is the mapping offset in the kth DRX cycle, 0≤Δ k <N k , Δ' k is the mapping offset in the kth DRX cycle, 0≤Δ' k <M R , k = 1, 2, ..., K, K is the number of DRX cycles.

2. The method according to claim 1, It is characterized in that 2Y of all UEs associated with the jth multicast in the kth DRX cycle k,j +1 time slot for sensing; among them, Y k,j It is the UE sensing interval configuration parameter in the jth multicast in the kth DRX cycle.

3. The method according to claim 1, It is characterized in that Keep the sensing interval of each multicast UE constant, Y k,j Simplified to Y j .

4. The method according to claim 2, It is characterized in that Using the continuous time slot sensing method, the sensing state S of the jth multicast service in the nth time slot of the kth DRX cycle is k,j (n)Configuration Where n=0,1,…,N k -1, Y k,j It is the UE sensing interval configuration parameter in the jth multicast in the kth DRX cycle.

5. The method according to claim 4, It is characterized in that S k,j (n)=1, the UE associated with the j-th multicast indicated by the target ID is activated for sensing in the n-th time slot in the k-th DRX cycle, otherwise the UE remains in the sleep mode.

6. The method according to claim 2, It is characterized in that Using the distributed time slot sensing method, in the kth DRX cycle, k,j N timeslots associated with the jth multicast service k The sensing state S of the time slot k,j (n k,j ) is configured as S k,j (n k,j )={S k,j (0),S k,j (1),…,S k,j (N k -1),}。 7. The method according to claim 4, It is characterized in that S k,j (n k,j ) k,j (n) is equal to 1, the UE associated with the j-th multicast indicated by the target ID is activated for sensing in the n-th time slot in the k-th DRX cycle, otherwise the UE remains in sleep mode.

8. The method according to claim 7, It is characterized in that Total time slots Through the set S k,j (n k,j ), that is, 9. The method according to claim 1, It is characterized in that A resource pool is defined as a subset of time slots and frequency resource blocks available for sidelink transmission or reception; a resource pool in the time domain is indicated by a bitmap and is repeated at certain intervals.

10. The method according to claim 9, It is characterized in that The repetition time interval of the resource pool is the same as the DRX cycle, or is an integer multiple of the DRX cycle.

11. The method according to claim 1, It is characterized in that The Tx UE associated with the jth group selects the rth k,j resource pools, and sends data packets in the kth DRX cycle; all Rx UEs associated with the jth group only need to access the rth k,j resource pools, and sensing is performed in all or part of the time slots in the kth DRX cycle.

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