US-12621849-B2 - Method and device for performing SL DRX operation in NR V2X on basis of HARQ feedback

US12621849B2US 12621849 B2US12621849 B2US 12621849B2US-12621849-B2

Abstract

Proposed is a method for a first device to perform wireless communication according to an embodiment. The method may comprise the steps of: acquiring an SL DRX configuration including information related to a sidelink discontinuous reception (SL DRX) cycle and information related to an active time; transmitting first sidelink control information (SCI) to a second device through a first physical sidelink control channel (PSCCH), wherein the first sidelink control information (SCI) is for scheduling a first physical sidelink control channel (PSSCH); transmitting second SCI and a first medium access control (MAC) protocol data unit (PDU) to the second device through the first PSSCH; determining a first physical sidelink feedback channel (PSFCH) resource in the first PSFCH slot on the basis of an index of a slot related to the first PSSCH and an index of a subchannel; and receiving a first hybrid automatic repeat request (HARQ) feedback for the first MAC PDU, the first HARQ feedback being received from the second device on the basis of the first PSFCH resource. For example, the first PSFCH slot may be included in an inactive time at the time of transmission of the first MAC PDU. For example, the first PSFCH slot may be included in an active time at the time of reception of the first HARQ feedback.

Inventors

Giwon Park
Seungmin Lee
Seoyoung Back
Jongwoo Hong

Assignees

LG ELECTRONICS INC.

Dates

Publication Date: 20260505
Application Date: 20211222

Claims (9)

1 . A method comprising: obtaining, by a first device, configuration information related to a sidelink discontinuous reception (SL DRX) including information related to an SL DRX cycle and information related to an active time; transmitting, by the first device, to a second device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH); transmitting, by the first device, to the second device, second SCI and a first medium access control (MAC) protocol data unit (PDU) through the first PSSCH; determining, by the first device, a first physical sidelink feedback channel (PSFCH) resource within a first PSFCH slot, based on an index of a slot and an index of a subchannel, related to the first PSSCH; and receiving, by the first device, from the second device, a first hybrid automatic repeat request (HARQ) feedback for the first MAC PDU based on the first PSFCH resource, wherein, based on an interval between a time point of transmitting the first MAC PDU and a time point of receiving the first HARQ feedback being smaller than a threshold, the first device remains in an active time during the interval, and wherein the threshold is determined based on a priority related to the first MAC PDU.
2 . The method of claim 1 , wherein, based on the first PSFCH slot being included within an inactive time at the time point of transmitting the first MAC PDU, the first device is transitioned to maintaining the active time during the interval between the time point of transmitting the first MAC PDU and the time point of receiving the first HARQ feedback.
3 . The method of claim 1 , wherein a timer related to SL DRX is started, based on transmitting the first MAC PDU, and wherein the first device operates as an active time until the timer related to SL DRX expires.
4 . The method of claim 1 , further comprising: transmitting, a third device, third SCI for scheduling a second PSSCH through a second PSCCH; transmitting, to the third device, fourth SCI and a second MAC PDU through the second PSSCH, wherein the first device is within an inactive time at a time point of receiving a second HARQ feedback for the second MAC PDU.
5 . The method of claim 4 , wherein the second MAC PDU is dropped, based on the second MAC PDU being a MAC PDU in which a HARQ feedback is enabled.
6 . The method of claim 4 , wherein the second MAC PDU is changed to a MAC PDU in which a HARQ feedback is disabled, based on the second MAC PDU being a MAC PDU in which a HARQ feedback is enabled.
7 . The method of claim 1 , wherein the first device receiving a HARQ feedback within an inactive time is allowed, based on at least one of a cast type, a service type, or a quality of service (QoS) requirement.
8 . A first device comprising: at least one transceiver; at least one processor; and at least one memory connected to the at least one processor and storing instructions that, based on being executed, cause the first device to perform operations comprising: obtaining configuration information related to a sidelink discontinuous reception (SL DRX) including information related to an SL DRX cycle and information related to an active time; transmitting, to a second device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH); transmitting, to the second device, second SCI and a first medium access control (MAC) protocol data unit (PDU) through the first PSSCH; determining a first physical sidelink feedback channel (PSFCH) resource within a first PSFCH slot, based on an index of a slot and an index of a subchannel, related to the first PSSCH; and receiving, from the second device, a first hybrid automatic repeat request (HARQ) feedback for the first MAC PDU based on the first PSFCH resource, wherein, based on an interval between a time point of transmitting the first MAC PDU and a time point of receiving the first HARQ feedback being smaller than a threshold, the first device remains in an active time during the interval, and wherein the threshold is determined based on a priority related to the first MAC PDU.
9 . A processing device comprising: at least one processor; and at least one memory connected to the at least one processor and storing instructions that, based on being executed, cause the at least one processor to control a first device to perform operations comprising: obtaining configuration information related to a sidelink discontinuous reception (SL DRX) including information related to an SL DRX cycle and information related to an active time; transmitting, to a second device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH); transmitting, to the second device, second SCI and a first medium access control (MAC) protocol data unit (PDU) through the first PSSCH; determining a first physical sidelink feedback channel (PSFCH) resource within a first PSFCH slot, based on an index of a slot and an index of a subchannel, related to the first PSSCH; and receiving, from the second device, a first hybrid automatic repeat request (HARQ) feedback for the first MAC PDU based on the first PSFCH resource, wherein, based on an interval between a time point of transmitting the first MAC PDU and a time point of receiving the first HARQ feedback being smaller than a threshold, the first device remains in an active time during the interval, and wherein the threshold is determined based on a priority related to the first MAC PDU.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a National Stage application under 35 U.S.C. § 371 of International Application No. PCT/KR2021/019666, filed on Dec. 22, 2021, which claims the benefit of U.S. Provisional Application No. 63/130,426, filed on Dec. 24, 2020, and U.S. Provisional Application No. 63/140,271, filed on Jan. 22, 2021. The disclosures of the prior applications are incorporated by reference in their entirety. TECHNICAL FIELD This disclosure relates to a wireless communication system. BACKGROUND Sidelink (SL) communication is a communication scheme in which a direct link is established between User Equipments (UEs) and the UEs exchange voice and data directly with each other without intervention of an evolved Node B (eNB). SL communication is under consideration as a solution to the overhead of an eNB caused by rapidly increasing data traffic. Vehicle-to-everything (V2X) refers to a communication technology through which a vehicle exchanges information with another vehicle, a pedestrian, an object having an infrastructure (or infra) established therein, and so on. The V2X may be divided into 4 types, such as vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), and vehicle-to-pedestrian (V2P). The V2X communication may be provided via a PC5 interface and/or Uu interface. Meanwhile, as a wider range of communication devices require larger communication capacities, the need for mobile broadband communication that is more enhanced than the existing Radio Access Technology (RAT) is rising. Accordingly, discussions are made on services and user equipment (UE) that are sensitive to reliability and latency. And, a next generation radio access technology that is based on the enhanced mobile broadband communication, massive Machine Type Communication (MTC), Ultra-Reliable and Low Latency Communication (URLLC), and so on, may be referred to as a new radio access technology (RAT) or new radio (NR). Herein, the NR may also support vehicle-to-everything (V2X) communication. SUMMARY On the other hand, in sidelink communication, in order to reduce the power of a UE, the UE may perform a sidelink discontinuous reception (SL DRX) operation. For example, when a transmitting UE (hereinafter referred to as a TX UE) transmits a physical sidelink control channel/physical sidelink shared channel (PSCCH/PSSCH) to a receiving UE (hereinafter referred to as an RX UE), and the TX UE receives a physical sidelink feedback channel (PSFCH) from the RX UE, it may occur that the time of the TX UE of receiving a PSFCH from the RX is during an inactive time period. Also, for example, if a TX UE is unable to receive PSFCHs from an RX UE within an inactive time period, a problem may occur that what characteristics/types of data or medium access control (MAC) protocol data units (PDUs) the TX UE will transmit in the active time slot. According to an embodiment of the present disclosure, a method for performing, by a first device, wireless communication may be proposed. The method may comprise: obtaining a sidelink discontinuous reception (SL DRX) configuration including information related to an SL DRX cycle and information related to an active time; transmitting, to a second device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH); transmitting, to the second device, second SCI and a first medium access control (MAC) protocol data unit (PDU) through the first PSSCH; determining a first physical sidelink feedback channel (PSFCH) resource within a first PSFCH slot, based on an index of a slot and an index of a subchannel, related to the first PSSCH; and receiving, from the second device, a first hybrid automatic repeat request (HARQ) feedback for the first MAC PDU based on the first PSFCH resource. For example, the first PSFCH slot may be included within an inactive time at a time point of transmitting the first MAC PDU. For example, the first PSFCH slot may be included within an active time at a time point of receiving the first HARQ feedback. According to an embodiment of the present disclosure, a first device for performing wireless communication may be proposed. For example, a first device may comprise: one or more memories storing instructions; one or more transceivers; and one or more processors connected to the one or more memories and the one or more transceivers. For example, the one or more processors may execute the instructions to: obtain a sidelink discontinuous reception (SL DRX) configuration including information related to an SL DRX cycle and information related to an active time; transmit, to a second device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH); transmit, to the second device, second SCI and a first medium access control (MAC)