Method and device for performing sl drix operation based on harq feedback in nr v2x

Abstract

A method by which a first device performs wireless communication is presented in one embodiment. The method can include obtaining a sidelink discontinuous reception (SL DRX) configuration; receiving, from a second device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) over a first physical sidelink control channel (PSCCH); receiving, from the second device, second SCI and first data over the first PSSCH; and determining a first physical sidelink feedback channel (PSFCH) resource based on a slot index and a subchannel index related to the first PSSCH. For example, a first timer included in the SL DRX configuration can be started based on omitting a first PSFCH transmission related to the first PSSCH over the first PSFCH resource.

Description

TECHNICAL FIELD

[0001] The disclosure relates to a wireless communication system. BACKGROUND

[0002] A sidelink (SL) communication is a communication scheme in which a direct link is established between user equipments (UEs) and the UEs directly exchange voice and data with each other without intervention of an evolved node B (eNB). The SL communication is under consideration as a solution to eNB overhead caused by rapid increase in data traffic. V2X (vehicle-to-everything) refers to a communication technique by which vehicles exchange information with other vehicles, pedestrians, and objects equipped with infrastructures, etc. The V2X can be divided into four types such as V2V (vehicle-to-vehicle), V2I (vehicle-to-infrastructure), V2N (vehicle-to-network), and V2P (vehicle-to-pedestrian). The V2X communication can be provided through a PC5 interface and / or a Uu interface.

[0003] In addition, as more communication devices demand greater communication capacity, there is an increasing need for mobile broadband communication enhanced with respect to a conventional radio access technology (RAT). Therefore, communication system design considering reliability and latency sensitive UEs or services has also been discussed. Also, a next-generation radio access technology based on enhanced mobile broadband communication, massive machine type communication (MTC), ultra-reliable low-latency communication (URLLC), etc. can be called a new RAT (radio access technology) or NR (new radio). Herein, the NR can also support vehicle-to-everything (V2X) communication.

[0004] Figure 1 is a diagram for describing NR-based V2X communication compared to V2X communication based on a RAT used prior to the NR. Figure 1 Embodiments of can be combined with various embodiments of the disclosure.

[0005] With respect to V2X communication, when a RAT used prior to the NR is discussed, a scheme focusing on providing a safety service based on a V2X message such as a BSM (basic safety message), a CAM (cooperative awareness message), and a DENM (decentralized environmental notification message) is discussed. The V2X message can include position information, dynamic information, attribute information, etc. For example, a UE can transmit a periodic message type CAM and / or an event triggered message type DENM to another UE.

[0006] Thereafter, with respect to V2X communication, various V2X scenarios are proposed in the NR. For example, the various V2X scenarios can include platooning, advanced driving, extended sensors, remote driving, etc. SUMMARY

[0007] TECHNICAL PROBLEM

[0008] Meanwhile, in sidelink communication, a UE can perform a sidelink discontinuous reception (SL DRX) operation to save power of the UE. For example, in a SL hybrid automatic repeat request (HARQ) feedback operation of transmitting only a negative acknowledgement (NACK), when a receiving UE performing the SL DRX operation skips / omits the NACK transmission, a transmitting UE can not perform an additional retransmission operation by assuming that the receiving UE has successfully received a MAC protocol data unit (PDU). On the other hand, since the receiving UE has not successfully received the MAC PDU, there can be a problem of resetting or extending a SL DRX timer.

[0009] Further, for example, in a SL HARQ feedback operation of transmitting ACK and NACK, when a receiving UE performing the SL DRX operation skips / omits the ACK transmission, a transmitting terminal can assume that the receiving UE has not received a MAC PDU and perform an additional retransmission operation. On the other hand, since the receiving UE has successfully received the MAC PDU, there can be a problem of not resetting or extending a SL DRX timer.

[0010] Technical solutions

[0011] According to an embodiment of the disclosure, a method for a first device to perform wireless communication is proposed. The method includes obtaining a sidelink discontinuous reception (SL DRX) configuration; receiving, from 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); receiving, from the second device, second SCI and first data through the first PSSCH; and determining a first physical sidelink feedback channel (PSFCH) resource based on an index of a slot and an index of a subchannel related to the first PSSCH, wherein a first timer included in the SL DRX configuration is started based on skipping, on the first PSFCH resource, a first PSFCH transmission related to the first PSSCH. For example, a first timer included in the SL DRX configuration is started based on skipping, on the first PSFCH resource, a first PSFCH transmission related to the first PSSCH.

[0012] According to embodiments of the present disclosure, a first device for performing wireless communication can be provided. For example, the first device can include one or more memories for storing instructions; one or more transceivers; and one or more processors connected the one or more memories and the one or more transceivers. For example, the one or more processors execute the instructions to obtain a sidelink discontinuous reception (SL DRX) configuration; receive, from 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); receive, from the second device, second SCI and first data through the first PSSCH; and determine a first physical sidelink feedback channel (PSFCH) resource based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource, a first timer included in the SL DRX configuration is started.

[0013] According to embodiments of the present disclosure, an apparatus configured to control the first UE can be provided. For example, one or more processors; and one or more memories operatively coupled with the one or more processors and storing instructions can be included. For example, the one or more processors execute the instructions to obtain a sidelink discontinuous reception (SL DRX) configuration; receive, from a second UE, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH); receive, from the second UE, second SCI and first data through the first PSSCH; and determine a first physical sidelink feedback channel (PSFCH) resource based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, wherein based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource, a first timer included in the SL DRX configuration is started.

[0014] According to embodiments of the disclosure, a non-transitory computer-readable medium (CRM) storing instructions can be provided. For example, the instructions, when executed, cause the first device to: obtain a sidelink discontinuous reception (SL DRX) configuration; receive, from 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); receive, from the second device, second SCI and first data through the first PSSCH; and determine a first physical sidelink feedback channel (PSFCH) resource based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, a first timer included in the SL DRX configuration is started based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource.

[0015] According to embodiments of the disclosure, a method for a second device to perform wireless communication is proposed. The method includes: transmitting, to a first device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH); and transmitting, to the first device, second SCI and first data through the first PSSCH. For example, a sidelink discontinuous reception (SL DRX) configuration is obtained. For example, wherein a first physical sidelink feedback channel (PSFCH) resource is determined based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, wherein a first timer included in the SL DRX configuration is started based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource.

[0016] According to an embodiment of the disclosure, a second device for performing wireless communication is provided. For example, the second device can include one or more memories to store instructions, one or more transceivers, and one or more processors connected with the one or more memories and the one or more transceivers. For example, the one or more processors execute the instructions to transmit, to a first device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH), and transmit, to the first device, second SCI and first data through the first PSSCH. For example, a sidelink discontinuous reception (SL DRX) configuration is obtained. For example, a first physical sidelink feedback channel (PSFCH) resource is determined based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, a first timer included in the SL DRX configuration is started based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource.

[0017] Advantageous Effects

[0018] In ACK / NACK-based hybrid automatic repeat request (HARQ) feedback, when a physical sidelink feedback channel (PSFCH) transmission is skipped / omitted, efficient SL communication can be performed by preventing a transmitting UE from repeating retransmission by mistakenly considering whether a negative acknowledgement (NACK).

[0019] Further, in HARQ feedback in which only a NACK is transmitted, when the PSFCH transmission is skipped / omitted, there can be an effective feature in terms of energy saving by not starting the SL DRX timer. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a diagram for describing NR-based V2X communication compared to V2X communication based on a RAT used before NR.

[0021] Figure 2 A structure of an NR system based on an embodiment of the disclosure is illustrated.

[0022] Figure 3 A radio protocol architecture based on an embodiment of the disclosure is illustrated.

[0023] Figure 4 A structure of a radio frame of NR based on an embodiment of the disclosure is illustrated.

[0024] Figure 5 A structure of a slot of an NR frame based on an embodiment of the disclosure is illustrated.

[0025] Figure 6 An example of a BWP based on embodiments of the disclosure is shown.

[0026] Figure 7 A UE performing V2X or SL communication according to embodiments of the disclosure is shown.

[0027] Figure 8 A procedure for a UE to perform V2X or SL communication based on a transmission mode according to embodiments of the disclosure is shown.

[0028] Figure 9 Three types of broadcast based on embodiments of the disclosure are shown.

[0029] Figure 10 A method for a UE in which transmission resources have been reserved to inform another UE of the transmission resources based on embodiments of the disclosure is shown.

[0030] Figure 11 A procedure for a receiving UE to start a timer related to SL DRX according to embodiments of the disclosure is shown.

[0031] Figure 12 Another procedure for a receiving UE to start a timer related to SL DRX according to embodiments of the disclosure is shown.

[0032] Figure 13 An example in which a receiving UE is located on a reserved resource after expiry of a timer related to SL DRX according to embodiments of the disclosure is shown.

[0033] Figure 14 A method for a first device to start a timer related to SL DRX according to embodiments of the disclosure is shown.

[0034] Figure 15 A method for starting a SL DRX timer according to embodiments of the disclosure is shown.

[0035] Figure 16 A communication system 1 based on embodiments of the disclosure is shown.

[0036] Figure 17 A wireless device based on embodiments of the disclosure is shown.

[0037] Figure 18 A signal processing circuit for transmitting a signal based on embodiments of the disclosure is shown.

[0038] Figure 19 Another example of a wireless device based on embodiments of the disclosure is shown.

[0039] Figure 20 A handheld device based on embodiments of the disclosure is shown.

[0040] Figure 21 A vehicle or autonomous vehicle based on embodiments of the disclosure is shown. DETAILED DESCRIPTION

[0041] In the disclosure, "A or B" can mean "A only", "B only", or "both A and B". In other words, in the disclosure, "A or B" can be interpreted as "A and / or B". For example, in the disclosure, "A, B, or C" can mean "A only", "B only", "C only", or "any combination of A, B, and C".

[0042] In the disclosure, a slash ( / ) or a comma used can mean "and / or". For example, "A / B" can mean "A and / or B". Thus, "A / B" can mean "A only", "B only", or "both A and B". For example, "A, B, C" can mean "A, B, or C".

[0043] In the disclosure, "at least one of A and B" can mean "A only", "B only", or "both A and B". Also, in the disclosure, the expression "at least one of A or B" or "at least one of A and / or B" can be interpreted as "at least one of A and B".

[0044] Also, in the disclosure, "at least one of A, B, and C" can mean "A only", "B only", "C only", or "any combination of A, B, and C". Also, "at least one of A, B, or C" or "at least one of A, B, and / or C" can mean "at least one of A, B, and C".

[0045] Also, the parentheses used in the disclosure can mean "for example". Specifically, when indicated as "control information (PDCCH)", this can mean that "PDCCH" is proposed as an example of "control information". In other words, the "control information" of the disclosure is not limited to "PDCCH", and "PDDCH" can be proposed as an example of "control information". Specifically, when indicated as "control information (i.e., PDCCH)", this can also mean that "PDCCH" is proposed as an example of "control information".

[0046] The technical features described in one drawing in the disclosure can be implemented respectively, or can be implemented simultaneously.

[0047] The technology described below can be used in various wireless communication systems such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), etc. The CDMA can be implemented using radio technology such as universal terrestrial radio access (UTRA) or CDMA-2000. The TDMA can be implemented using radio technology such as global system for mobile communications (GSM) / general packet radio service (GPRS) / enhanced data rates for GSM evolution (EDGE). The OFDMA can be implemented using radio technology such as institute of electrical and electronics engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, evolved UTRA (E-UTRA), etc. IEEE 802.16m is an evolution of IEEE 802.16e, and provides backward compatibility with an IEEE 802.16e-based system. The UTRA is a part of a universal mobile telecommunications system (UMTS). 3rd generation partnership project (3GPP) long term evolution (LTE) is a part of an evolved UMTS (E-UMTS). The 3GPP LTE uses the OFDMA in downlink and uses the SC-FDMA in uplink. LTE-higher advanced (LTE-A) is an evolution of the LTE.

[0048] 5G NR is a subsequent technology to LTE-A corresponding to a new and full mobile communication system having high performance, low latency, high availability, etc. The 5G NR can use resources of all available frequency spectrums including a low frequency band less than 1 GHz, an intermediate frequency band from 1 GHz to 10 GHz, and a high frequency (millimeter wave) of 24 GHz or more.

[0049] For clarity of description, the following description will mainly focus on LTE-A or 5G NR. However, the technical features according to the embodiments of the disclosure will not be limited thereto.

[0050] Figure 2 The structure of an NR system according to an embodiment of the disclosure is illustrated. Figure 2 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0051] Reference Figure 2The next generation radio access network (NG-RAN) can include BSs 20 that provide user plane and control plane protocol terminations towards the UE 10. For example, the BS 20 can include a next generation NodeB (gNB) and / or an evolved NodeB (eNB). For example, the UE 10 can be fixed or mobile, and can be referred to as other terminology, such as a mobile station (MS), user terminal (UT), subscriber station (SS), mobile terminal (MT), wireless device, etc. For example, the BS can be referred to as a fixed station that communicates with the UE 10 and can be referred to as other terminology, such as a base transceiver system (BTS), access point (AP), etc.

[0052] Figure 2 Embodiments of the disclosure exemplify a case where only gNBs are included. The BSs 20 can be connected to each other via an Xn interface. The BSs 20 can be connected to each other via a fifth generation (5G) core network (5GC) and an NG interface. More specifically, the BSs 20 can be connected to an access and mobility management function (AMF) 30 via an NG-C interface, and can be connected to a user plane function (UPF) 30 via an NG-U interface.

[0053] Radio interface protocol layers between the UE and the network can be classified as a first layer (L1), a second layer (L2), and a third layer (L3) based on the lower three layers of the open system interconnection (OSI) model commonly known in communication systems. Among them, the physical (PHY) layer belonging to the first layer provides an information transfer service using a physical channel, and the radio resource control (RRC) layer located at the third layer controls radio resources between the UE and the network. To this end, the RRC layer exchanges RRC messages between the UE and the BS layer.

[0054] Figure 3 A radio protocol architecture based on embodiments of the disclosure is shown. Figure 3 Embodiments of the disclosure can be combined with various embodiments of the disclosure. Specifically, Figure 3 (a) of FIG. 1 shows a radio protocol stack for a user plane for Uu communication, and Figure 3 (b) of FIG. 1 shows a radio protocol stack for a control plane for Uu communication. Figure 3 (c) of FIG. 1 shows a radio protocol stack for a user plane for SL communication, and Figure 3 (d) of FIG. 1 shows a radio protocol stack for a control plane for SL communication.

[0055] Referring to Figure 3The physical layer provides a service by using a physical channel to an upper layer. The physical layer is connected to a Medium Access Control (MAC) layer, which is an upper layer of the physical layer, through a transport channel. Data is transferred between the MAC layer and the physical layer through the transport channel. The transport channel is classified according to how and what data are transferred through a radio interface.

[0056] Data is transferred through a physical channel between different physical layers, i.e. between the PHY layer of the transmitter and the PHY layer of the receiver. The physical channel can be modulated using an Orthogonal Frequency Division Multiplexing (OFDM) scheme and uses time and frequency as radio resources.

[0057] The MAC layer provides a service to a Radio Link Control (RLC) layer via a logical channel. The RLC layer is an upper layer of the MAC layer. The MAC layer provides a function of mapping multiple logical channels to multiple transport channels. The MAC layer also provides a function of logical channel multiplexing by mapping multiple logical channels to a single transport channel. The MAC layer provides a data transfer service through a logical channel.

[0058] The RLC layer performs concatenation, segmentation, and reassembly of a Radio Link Control Service Data Unit (RLC SDU). In order to ensure different Quality of Service (QoS) required by a radio bearer (RB), the RLC layer provides three types of operation modes, i.e. a Transparent Mode (TM), an Unacknowledged Mode (UM), and an Acknowledged Mode (AM). The AM RLC provides error correction through an Automatic Repeat reQuest (ARQ).

[0059] The Radio Resource Control (RRC) layer is defined only in the control plane. The RRC layer is used for the control of the configuration, reconfiguration, and release of a logical channel, a transport channel, and a physical channel associated with a radio bearer (RB). The RB is a logical path provided by the first layer (i.e., the physical layer or PHY layer) and the second layer (i.e., the MAC layer, the RLC layer, the Packet Data Convergence Protocol (PDCP) layer, and the Service Data Adaptation Protocol (SDAP) layer) for data transmission between the UE and the network.

[0060] The functions of the Packet Data Convergence Protocol (PDCP) in the user plane include the transfer of user data, header compression, and encryption. The functions of the Packet Data Convergence Protocol (PDCP) in the control plane include the transfer of control plane data and ciphering / integrity protection.

[0061] The Service Data Adaptation Protocol (SDAP) layer is defined only in the user plane. The SDAP layer performs mapping between a Quality of Service (QoS) flow and a data radio bearer (DRB) and QoS flow ID (QFI) marking in both a DL packet and a UL packet.

[0062] The configuration of the RB implies a process for specifying a radio protocol layer and a channel property to provide a specific service and for determining a corresponding detailed parameter and operation method. The RB can then be classified into two types, i.e., a signaling radio bearer (SRB) and a data radio bearer (DRB). The SRB is used as a path for transmitting an RRC message in a control plane, and the DRB is used as a path for transmitting user data in a user plane.

[0063] When an RRC connection is established between an RRC layer of a UE and an RRC layer of an E-UTRAN, the UE is in an RRC connected (RRC_CONNECTED) state, and otherwise the UE can be in an RRC idle (RRC_IDLE) state. In the case of NR, an RRC inactive (RRC_INACTIVE) state is additionally defined, and a UE in the RRC_INACTIVE state can maintain a connection with a core network while releasing its connection with a BS.

[0064] A downlink transport channel for transmitting (or delivering) data from the network to the UE includes a broadcast channel (BCH) for transmitting system information and a downlink shared channel (SCH) for transmitting user traffic or control messages. Traffic or control messages of a downlink multicast or broadcast service can be transmitted via the downlink SCH or can be transmitted via a separate downlink multicast channel (MCH). In addition, an uplink transport channel for transmitting (or delivering) data from the UE to the network includes a random access channel (RACH) for transmitting initial control messages and an uplink shared channel (SCH) for transmitting user traffic or control messages.

[0065] Examples of a logical channel belonging to a higher layer than the transport channel and mapped to the transport channel can include a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and a multicast traffic channel (MTCH).

[0066] Figure 4 The structure of a radio frame of the NR according to an embodiment of the present disclosure is illustrated. Figure 4 Embodiments of the present disclosure can be combined with various embodiments of the present disclosure.

[0067] Referring to Figure 4 In the NR, a radio frame can be used to perform uplink and downlink transmission. The length of the radio frame is 10 ms, and can be defined as consisting of two half frames (HF). The half frame can include five 1 ms subframes (SF). The subframe (SF) can be divided into one or more slots, and the number of slots within the subframe can be determined according to a subcarrier spacing (SCS). Each slot can include 12 or 14 OFDM(A) symbols according to a cyclic prefix (CP).

[0068] In case of using normal CP, each slot can include 14 symbols. In case of using extended CP, each slot can include 12 symbols. Herein, a symbol can include an OFDM symbol (or CP-OFDM symbol) and a single carrier-FDMA (SC-FDMA) symbol (or discrete Fourier transform-spread-OFDM (DFT-s-OFDM) symbol).

[0069] Table 1 shown below represents the number of symbols (N slot symb ) per slot, the number of slots (N frame,μ slot ) per frame, and the number of slots (N subframe,μ slot ) per subframe according to an SCS setting (μ) in case of using normal CP.

[0070] [Table 1]

[0071]

[0072] Table 2 shows an example of the number of symbols per slot, the number of slots per frame, and the number of slots per subframe according to an SCS in case of using extended CP.

[0073] [Table 2]

[0074]

[0075] In the NR system, OFDM(A) numerologies (e.g., SCS, CP length, etc.) between a plurality of cells integrated into one UE can be configured differently. Accordingly, the (absolute time) duration (or interval) of a time resource (e.g., subframe, slot, or TTI) (for simplicity, collectively referred to as time unit (TU)) composed of the same number of symbols can be configured differently in the integrated cells.

[0076] In the NR, a plurality of numerologies or SCSs for supporting various 5G services can be supported. For example, in case of SCS of 15 kHz, a wide range of legacy cellular bands can be supported, and in case of SCS of 30 kHz / 60 kHz, dense urban, lower latency, wider carrier bandwidths can be supported. In case of SCS of 60 kHz or more, in order to overcome phase noise, a bandwidth greater than 24.25 GHz can be used.

[0077] The NR band can be defined as two different types of frequency ranges. The two different types of frequency ranges can be FR1 and FR2. Values of the frequency ranges can be changed (or varied), for example, the two different types of frequency ranges can be as shown in Table 3 below. Among the frequency ranges used in the NR system, FR1 can mean a "sub-6 GHz range", and FR2 can mean a "higher than 6 GHz range", and can also be referred to as millimeter wave (mmW).

[0078] [Table 3]

[0079] Frequency Range Designation Corresponding Frequency Range Subcarrier Spacing (SCS) FR1 450 MHz - 6000 MHz 15, 30, 60 kHz FR2 24250 MHz - 52600 MHz 60, 120, 240 kHz

[0080] As described above, values of the frequency ranges in the NR system can be changed (or varied). For example, as shown in Table 4 below, FR1 can include a bandwidth in a range of 410 MHz to 7125 MHz. More specifically, FR1 can include a 6 GHz (or 5850, 5900, 5925 MHz, etc.) and higher frequency band. For example, the 6 GHz (or 5850, 5900, 5925 MHz, etc.) and higher frequency band included in FR1 can include an unlicensed band. The unlicensed band can be used for various purposes, for example, the unlicensed band is used for vehicle-specific communication (e.g., autonomous driving).

[0081] [Table 4]

[0082] Frequency Range Designation Corresponding Frequency Range Subcarrier Spacing (SCS) FR1 410 MHz - 7125 MHz 15, 30, 60 kHz FR2 24250 MHz - 52600 MHz 60, 120, 240 kHz

[0083] Figure 5 A structure of a slot of an NR frame according to an embodiment of the disclosure is illustrated. Figure 5 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0084] Referring to Figure 5 , a slot includes a plurality of symbols in the time domain. For example, one slot can include 14 symbols in the case of a normal CP. For example, one slot can include 12 symbols in the case of an extended CP. Alternatively, one slot can include 7 symbols in the case of a normal CP. However, one slot can include 6 symbols in the case of an extended CP.

[0085] A carrier includes multiple subcarriers in a frequency domain. A resource block (RB) can be defined as multiple contiguous subcarriers (e.g., 12 subcarriers) in the frequency domain. A bandwidth part (BWP) can be defined as multiple contiguous (physical) resource blocks ((P)RBs) in the frequency domain, and a BWP can correspond to one numerology (e.g., SCS, CP length, etc.). A carrier can include up to N BWPs (e.g., 5 BWPs). Data communication can be performed via an activated BWP. Each element can be referred to as a resource element (RE) in a resource grid, and one complex symbol can be mapped to each element.

[0086] Hereinafter, a bandwidth part (BWP) and a carrier will be described in detail.

[0087] A BWP can be a contiguous set of physical resource blocks (PRBs) within a given numerology. The PRBs can be selected from a contiguous set of common resource blocks (CRBs) for a given numerology on a given carrier.

[0088] For example, a BWP can be at least any one of an active BWP, an initial BWP, and / or a default BWP. For example, a UE can not monitor a downlink radio link quality in a DL BWP other than an activated DL BWP on a primary cell (PCell). For example, a UE can not receive a PDCCH, a physical downlink shared channel (PDSCH), or a channel state information-reference signal (CSI-RS) (excluding RRM) other than an activated DL BWP. For example, a UE can not trigger a channel state information (CSI) report for a non-activated DL BWP. For example, a UE can not transmit a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) other than an activated UL BWP. For example, in the case of downlink, an initial BWP can be given as a contiguous RB set for a remaining minimum system information (RMSI) control resource set (CORESET) (configured by a physical broadcast channel (PBCH)). For example, in the case of uplink, an initial BWP can be given by a system information block (SIB) for a random access procedure. For example, a default BWP can be configured by a higher layer. For example, an initial value of a default BWP can be an initial DL BWP. For power saving, if a UE fails to detect a downlink control information (DCI) during a specified period, the UE can switch an active BWP of the UE to a default BWP.

[0089] Further, a BWP can be defined for SL. The same SL BWP can be used in transmission and reception. For example, a transmitting UE can transmit a SL channel or a SL signal on a certain BWP, and a receiving UE can receive a SL channel or a SL signal on a certain BWP. In a licensed carrier, a SL BWP can be defined separately from a Uu BWP, and a SL BWP can have separate configuration signaling from a Uu BWP. For example, a UE can receive a configuration for a SL BWP from a BS / network. For example, a UE can receive a configuration for a Uu BWP from a BS / network. A SL BWP is (pre-)configured in a carrier for out-of-coverage NR V2X UEs and RRC_IDLE UEs. For a UE in RRC_CONNECTED mode, at least one SL BWP can be activated in a carrier.

[0090] Figure 6 An example of a BWP according to an embodiment of the disclosure is illustrated. Figure 6 Embodiments of the disclosure can be combined with various embodiments of the disclosure. It is assumed that in Figure 6 In embodiments of the disclosure, the number of BWPs is 3.

[0091] Referring to Figure 6 , a common resource block (CRB) can be a carrier resource block numbered from one end of a carrier frequency band to the other end thereof. In addition, a PRB can be a resource block numbered within each BWP. Point A can indicate a common reference point of a resource block grid.

[0092] A BWP can be configured by a point A, an offset (N start BWP ) with respect to the point A, and a bandwidth (N size BWP ). For example, the point A can be an outer reference point of a PRB of a carrier, and subcarrier 0 of all numerologies (e.g., all numerologies supported by a network on a corresponding carrier) is aligned in the point A. For example, the offset can be a PRB distance between a lowest subcarrier within a given numerology and the point A. For example, the bandwidth can be the number of PRBs within a given numerology.

[0093] Hereinafter, V2X or SL communication will be described.

[0094] A sidelink synchronization signal (SLSS) can include a primary sidelink synchronization signal (PSSS) and a secondary sidelink synchronization signal (SSSS) as SL-specific sequences. The PSSS can be referred to as a sidelink primary synchronization signal (S-PSS), and the SSSS can be referred to as a sidelink secondary synchronization signal (S-SSS). For example, a length-127 M-sequence can be used for the S-PSS, and a length-127 Gold sequence can be used for the S-SSS. For example, a UE can use the S-PSS for initial signal detection and synchronization acquisition. For example, the UE can use the S-PSS and the S-SSS for acquisition of detailed synchronization and for detection of a synchronization signal ID.

[0095] A physical sidelink broadcast channel (PSBCH) can be a (broadcast) channel for transmitting default (system) information that a UE must first know before SL signal transmission / reception. For example, the default information can be information related to an SLSS, a duplex mode (DM), a time division duplex (TDD) uplink / downlink (UL / DL) configuration, information related to a resource pool, a type of application related to an SLSS, a subframe offset, broadcast information, etc. For example, in order to evaluate PSBCH performance, a payload size of the PSBCH can be 56 bits including a 24-bit cyclic redundancy check (CRC) in NR V2X.

[0096] The S-PSS, the S-SSS, and the PSBCH can be included in a block format (e.g., a SL synchronization signal (SS) / PSBCH block, hereinafter, a sidelink synchronization signal block (S-SSB)) that supports periodic transmission. The S-SSB can have the same numerology (i.e., SCS and CP length) as a physical sidelink control channel (PSCCH) / physical sidelink shared channel (PSSCH) in a carrier, and a transmission bandwidth can exist within a (pre-)configured sidelink (SL) BWP. For example, the S-SSB can have a bandwidth of 11 resource blocks (RBs). For example, the PSBCH can exist across 11 RBs. In addition, a frequency location of the S-SSB can be (pre-)configured. Thus, a UE does not have to perform hypothesis detection at a frequency to discover the S-SSB in a carrier.

[0097] Figure 7 A UE performing V2X or SL communication according to an embodiment of the disclosure is illustrated. Figure 7 Embodiments thereof can be combined with various embodiments of the disclosure.

[0098] Reference Figure 7In V2X or SL communication, the term "UE" can generally refer to a UE of a user. However, if a network device such as a BS transmits / receives a signal according to a communication scheme between UEs, the BS can also be regarded as a kind of UE. For example, UE 1 can be a first device 100, and UE 2 can be a second device 200.

[0099] For example, UE 1 can select a resource unit corresponding to a specific resource in a resource pool meaning a set of resource series. In addition, UE 1 can transmit an SL signal by using the resource unit. For example, the resource pool in which UE 1 is capable of transmitting a signal can be configured to UE 2 which is a receiving UE, and a signal of UE 1 can be detected in the resource pool.

[0100] Herein, if UE 1 is within a connection range of a BS, the BS can inform UE 1 of a resource pool. Otherwise, if UE 1 is outside the connection range of the BS, another UE can inform UE 1 of a resource pool, or UE 1 can use a pre-configured resource pool.

[0101] Generally, a resource pool can be configured in units of a plurality of resources, and each UE can select a unit of one or more resources to use it in its SL signal transmission.

[0102] Hereinafter, resource allocation in SL will be described.

[0103] Figure 8 A procedure of performing V2X or SL communication by a UE based on a transmission mode according to an embodiment of the disclosure is illustrated. Figure 8 Embodiments of the disclosure can be combined with various embodiments of the disclosure. In various embodiments of the disclosure, a transmission mode can be referred to as a mode or a resource allocation mode. Hereinafter, for convenience of explanation, in LTE, a transmission mode can be referred to as an LTE transmission mode. In NR, a transmission mode can be referred to as an NR resource allocation mode.

[0104] For example, Figure 8 (a) of FIG. 1 illustrates UE operation related to LTE transmission mode 1 or LTE transmission mode 3. Alternatively, for example, Figure 8 (a) of FIG. 1 illustrates UE operation related to LTE transmission mode 1 or LTE transmission mode 3. Alternatively, for example,

[0105] For example, Figure 8 (b) of FIG. 1 illustrates UE operation related to LTE transmission mode 2 or LTE transmission mode 4. Alternatively, for example, Figure 8 (b) of FIG. 1 illustrates UE operation related to LTE transmission mode 2 or LTE transmission mode 4. Alternatively, for example,

[0106] Reference Figure 8 In (a) of this document, in LTE transmission mode 1, LTE transmission mode 3, or NR resource allocation mode 1, the BS can schedule SL resources for the UE to use for SL transmission. For example, the BS can perform resource scheduling for UE 1 via PDCCH (e.g., Downlink Control Information (DCI)) or RRC signaling (e.g., Configuration License Type 1 or Configuration License Type 2), and UE 1 can perform V2X or SL communication against UE 2 based on the resource scheduling. For example, UE 1 can send Sidelink Control Information (SCI) to UE 2 via the Physical Sidelink Control Channel (PSCCH), and subsequently send SCI-based data to UE 2 via the Physical Sidelink Shared Channel (PSSCH).

[0107] Reference Figure 8 In (b) of this document, under LTE transmission mode 2, LTE transmission mode 4, or NR resource allocation mode 2, the UE can determine the SL transmission resource within the SL resources configured by the BS / network or the pre-configured SL resources. For example, the configured or pre-configured SL resources can be a resource pool. For example, the UE can autonomously select or schedule resources for SL transmission. For example, the UE can perform SL communication by autonomously selecting resources from the configured resource pool. For example, the UE can autonomously select resources within a selection window by performing a sensing and resource (re)selection process. For example, sensing can be performed on a sub-channel basis. Furthermore, UE 1, which has autonomously selected resources from the resource pool, can send SCI to UE 2 via PSCCH, and subsequently send SCI-based data to UE 2 via PSSCH.

[0108] Figure 9 Three broadcast types according to embodiments of this disclosure are shown. Figure 9 The embodiments can be combined with various embodiments of this disclosure. Specifically, Figure 9 (a) in the diagram illustrates broadcast SL communication. Figure 9 (b) shows unicast SL communication, and Figure 9 (c) illustrates multicast SL communication. In the case of unicast SL communication, a UE can perform one-to-one communication with another UE. In the case of multicast SL transmission, a UE can perform SL communication with one or more UEs in a group to which it belongs. In various embodiments of this disclosure, SL multicast communication can be replaced by SL multicast communication, SL one-to-many communication, etc.

[0109] Meanwhile, in the disclosure, for example, a transmitting UE (TX UE) can be a UE that transmits data to a (target) receiving UE (RX UE). For example, the TX UE can be a UE that performs PSCCH transmission and / or PSSCH transmission. Additionally / alternatively, for example, the TX UE can be a UE that transmits a SL CSI-RS and / or a SL CSI report request indicator to the (target) RX UE. Additionally / alternatively, for example, the TX UE can be a UE that transmits a (control) channel (e.g., PSCCH, PSSCH, etc.) and / or a reference signal (e.g., DM-RS, CSI-RS, etc.) on the (control) channel for SL RLM operation and / or SL RLF operation of the (target) RX UE.

[0110] Meanwhile, in the disclosure, for example, a receiving UE (RX UE) can be a UE that transmits SL HARQ feedback to a transmitting UE (TX UE) based on whether decoding of data received from the TX UE is successful and / or whether detection / decoding of a PSCCH (related to PSSCH scheduling) transmitted by the TX UE is successful. Additionally / alternatively, for example, the RX UE can be a UE that performs SL CSI transmission to the TX UE based on a SL CSI-RS and / or a SL CSI report request indicator received from the TX UE. Additionally / alternatively, for example, the RX UE is a UE that transmits, to the TX UE, a SL (L1) reference signal received power (RSRP) measurement value measured based on a SL (L1) RSRP report request indicator and / or a (predefined) reference signal received from the TX UE. Additionally / alternatively, for example, the RX UE can be a UE that transmits data of the RX UE to the TX UE. Additionally / alternatively, for example, the RX UE can be a UE that performs SL RLM operation and / or SL RLF operation based on a (preconfigured) (control) channel and / or a reference signal on the (control) channel received from the TX UE.

[0111] Meanwhile, in the disclosure, for example, in the case where the RX UE transmits SL HARQ feedback information for a PSSCH and / or a PSCCH received from the TX UE, the following options or some of the following options can be considered. Here, for example, only when the RX UE successfully decodes / detects a PSCCH scheduling a PSSCH, the following options or some of the following options can be restrictively applied.

[0112] (1) Multicast Option 1: Only when the RX UE fails to decode / receive a PSSCH received from the TX UE, NACK information can be transmitted to the TX UE.

[0113] (2) Multicast Option 2: If the RX UE successfully decodes / receives the PSSCH received from the TX UE, ACK information can be transmitted to the TX UE, and if the RX UE fails to decode / receive the PSSCH, NACK information can be transmitted to the TX UE.

[0114] Meanwhile, in the disclosure, for example, the TX UE can transmit the following information or some of the following information to the RX UE through the SCI. Herein, for example, the TX UE can transmit the following information or some of the following information to the RX UE through the first SCI and / or the second SCI.

[0115] - PSSCH (and / or PSCCH) related resource allocation information (e.g., location / quantity of time / frequency resources, resource reservation information (e.g., time period))

[0116] - SL CSI reporting request indicator or SL (L1) Reference Signal Received Power (RSRP) (and / or SL (L1) Reference Signal Received Quality (RSRQ) and / or SL (L1) Reference Signal Strength Indicator (RSSI)) reporting request indicator

[0117] - SL CSI transmission indicator (or SL (L1) RSRP (and / or SL (L1) RSRQ and / or SL (L1) RSSI) information transmission indicator) (on PSSCH)

[0118] - Modulation and coding scheme (MCS) information

[0119] - TX power information

[0120] - L1 destination ID information and / or L1 source ID information

[0121] - SL HARQ process ID information

[0122] - New data indicator (NDI) information

[0123] - Redundancy version (RV) information

[0124] - QoS information (e.g., priority information) related to (transmitted) SL CSI-RS

[0125] - Information on the number of antenna ports for (transmitted) SL CSI-RS or SL CSI-RS transmission indicator

[0126] - Location (or distance range) information of the target RX UE (for which SL HARQ feedback is requested) or TX UE location information

[0127] - Reference signal (e.g., DM-RS, etc.) information related to decoding (and / or channel estimation) of data transmitted over PSSCH. For example, information related to a pattern of (time-frequency) mapping resources of DM-RS, rank information, antenna port index information, information on a number of antenna ports, etc.

[0128] Meanwhile, in the present disclosure, for example, because a TX UE can transmit SCI, first SCI, and / or second SCI to a RX UE over PSCCH, PSCCH can be replaced / alternated with SCI and / or first SCI and / or second SCI. Additionally / alternatively, SCI can be replaced / alternated with PSCCH and / or first SCI and / or second SCI. Additionally / alternatively, for example, because a TX UE can transmit second SCI to a RX UE over PSSCH, PSSCH can be replaced / alternated with second SCI.

[0129] Meanwhile, in the present disclosure, for example, if SCI configuration fields are divided into two groups in consideration of a (relatively) high SCI payload size, a first SCI including a first group of SCI configuration fields can be referred to as a first SCI, and a second SCI including a second group of SCI configuration fields can be referred to as a second SCI. Further, for example, a first SCI can be transmitted to a receiving UE over PSCCH. Further, for example, a second SCI can be transmitted to a receiving UE over a (separate) PSCCH or can be piggybacked and transmitted together with data over PSSCH.

[0130] Meanwhile, in the present disclosure, for example, the term "configured" or the term "defined" can refer to (pre)configuration from a base station or a network (for each resource pool) through predefined signaling (e.g., SIB, MAC, RRC, etc.).

[0131] Meanwhile, in the present disclosure, for example, because RLF can be determined based on an out-of-sync (OOS) indicator or an in-sync (IS) indicator, RLF can be replaced / alternated with an out-of-sync (OOS) indicator or an in-sync (IS) indicator.

[0132] Meanwhile, in the present disclosure, for example, a RB can be replaced / alternated with a subcarrier. Further, in the present disclosure, for example, a packet or traffic can be replaced / alternated with a TB or a MAC PDU based on a transmission layer.

[0133] Meanwhile, in the present disclosure, a CBG can be replaced / alternated with a TB.

[0134] Meanwhile, in the present disclosure, for example, a source ID can be replaced / alternated with a destination ID.

[0135] Meanwhile, in the disclosure, for example, an L1 ID can be replaced / replaced by an L2 ID. For example, the L1 ID can be an L1 source ID or an L1 destination ID. For example, the L2 ID can be an L2 source ID or an L2 destination ID.

[0136] Meanwhile, in the disclosure, for example, the operation in which the transmitting UE reserves / selects / determines a retransmission resource can include the operation in which the transmitting UE reserves / selects / determines a potential retransmission resource whose actual use will be determined based on SL HARQ feedback information received from the receiving UE.

[0137] Meanwhile, in the disclosure, the sub-selection window can be replaced / replaced by a selection window and / or a preconfigured number of resource sets within the selection window, or vice versa.

[0138] Meanwhile, in the disclosure, SL MODE 1 can refer to a resource allocation method or a communication method in which a base station directly schedules SL transmission resources for a TX UE through pre-defined signaling (e.g., DCI or RRC message). For example, SL MODE 2 can refer to a resource allocation method or a communication method in which a UE independently selects SL transmission resources in a resource pool pre-configured or configured by a base station or a network. For example, a UE performing SL communication based on SL MODE 1 can be referred to as a MODE 1 UE or a MODE 1 TX UE, and a UE performing SL communication based on SL MODE 2 can be referred to as a MODE 2 UE or a MODE 2 TX UE.

[0139] Meanwhile, in the disclosure, for example, a dynamic grant (DG) can be replaced / replaced by a configured grant (CG) and / or a semi-persistent scheduling (SPS) grant, or vice versa. For example, the DG can be replaced / replaced by a combination of the CG and the SPS grant, or vice versa. For example, the CG can include at least one of a configured grant (CG) type 1 and / or a configured grant (CG) type 2. For example, in the CG type 1, a grant can be provided by RRC signaling and can be stored as a configured grant. For example, in the CG type 2, a grant can be provided by a PDCCH, and can be stored or deleted as a configured grant based on L1 signaling indicating the activation or deactivation of the grant.

[0140] In addition, in the disclosure, a channel can be replaced / replaced by a signal, or vice versa. For example, the transmission / reception of a channel can include the transmission / reception of a signal. For example, the transmission / reception of a signal can include the transmission / reception of a channel. In addition, for example, a play can be replaced / replaced by at least one of unicast, groupcast, and / or broadcast, or vice versa. For example, a play type can be replaced / replaced by at least one of unicast, groupcast, and / or broadcast, or vice versa.

[0141] Also, in the disclosure, a resource can be replaced / alternated with a time slot or a symbol, or vice versa. For example, a resource can include a time slot and / or a symbol.

[0142] Meanwhile, in the disclosure, a priority can be replaced / alternated with at least one of a logical channel priority (LCP), a latency, a reliability, a minimum required communication range, a per-packet priority (PPPP), a sidelink radio bearer (SLRB), a QoS profile, a QoS parameter, and / or a requirement, or vice versa.

[0143] Meanwhile, in various embodiments of the disclosure, a reserved resource and / or a selected resource can be replaced with a sidelink grant (SL GRANT).

[0144] Meanwhile, in various embodiments of the disclosure, a latency can be replaced with a packet delay budget (PDB).

[0145] Meanwhile, in various embodiments of the disclosure, a message for triggering a report on sidelink channel state information / sidelink channel quality information (hereinafter referred to as SL_CSI information) can be replaced with a sidelink channel state information reference signal (CSI-RS) reception.

[0146] Meanwhile, in the disclosure, a blind retransmission can refer to a retransmission performed by a TX UE without receiving SL HARQ feedback information from an RX UE. For example, a SL HARQ feedback-based retransmission can refer to a retransmission performed by a TX UE based on SL HARQ feedback information received from an RX UE. For example, if the TX UE receives NACK and / or DTX information from the RX UE, the TX UE can perform a retransmission to the RX UE.

[0147] Also, in the disclosure, for example, for convenience of description, a (physical) channel used when an RX UE transmits at least one of the following information to a TX UE can be referred to as a PSFCH.

[0148] -SL HARQ feedback, SL CSI, SL (L1) RSRP

[0149] Meanwhile, in the disclosure, a Uu channel can include a UL channel and / or a DL channel. For example, a UL channel can include a PUSCH, a PUCCH, a sounding reference signal (SRS), etc. For example, a DL channel can include a PDCCH, a PDSCH, a PSS / SSS, etc. For example, a SL channel can include a PSCCH, a PSSCH, a PSFCH, a PSBCH, a PSSS / SSSS, etc.

[0150] Meanwhile, in the NR V2X communication or the NR sidelink communication, the transmitting UE can reserve / select one or more transmission resources for the sidelink transmission (e.g., initial transmission and / or retransmission), and the transmitting UE can transmit information about locations of the one or more transmission resources to the receiving UE.

[0151] Meanwhile, when the sidelink communication is performed, the method in which the transmitting UE reserves or determines the transmission resources for the receiving UE can be representatively as follows.

[0152] For example, the transmitting UE can perform the reservation of the transmission resources based on a chain. Specifically, for example, if the transmitting UE reserves K transmission resources, the transmitting UE can transmit the location information of less than K transmission resources to the receiving UE through the SCI transmitted to the receiving UE at any (or specific) transmission time or time resource. That is, for example, the SCI can include the location information of less than K transmission resources. Alternatively, for example, if the transmitting UE reserves K transmission resources related to a specific TB, the transmitting UE can transmit the location information of less than K transmission resources to the receiving UE through the SCI transmitted to the receiving UE at any (or specific) transmission time or time resource. That is, the SCI can include the location information of less than K transmission resources. In this case, for example, by signaling the location information of less than K transmission resources to the receiving UE via only one SCI transmitted by the transmitting UE at any (or specific) transmission time or time resource, performance degradation due to an excessive increase in the payload of the SCI can be prevented.

[0153] Figure 10 A method in which a UE having reserved transmission resources based on an embodiment of the disclosure informs another UE of the transmission resources is shown. Figure 10 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0154] Specifically, for example, Figure 10 (a) of FIG. 1 shows a method in which, in the case of a value K = 4, the chain-based resource reservation by the transmitting UE is performed by transmitting / signaling the location information of (maximum) 2 transmission resources to the receiving UE via one SCI. For example, referring to Figure 10 (b) of FIG. 1 shows a method in which, in the case of a value K = 4, the chain-based resource reservation by the transmitting UE is performed by transmitting / signaling the location information of (maximum) 3 transmission resources to the receiving UE via one SCI. For example, referring to Figure 10 (a) and (b) of FIG. 1, the transmitting UE can transmit / signaling the location information of only the fourth transmission-related resource to the receiving UE through the fourth (or last) transmission-related PSCCH. For example, referring to Figure 10(a), the transmitting UE can transmit / signal the location information of the fourth transmission related resource to the receiving UE through the fourth (or last) transmission related PSCCH, in addition to the location information of the third transmission related resource. For example, referring to Figure 10 (b), the transmitting UE can transmit / signal the location information of the fourth transmission related resource to the receiving UE through the fourth (or last) transmission related PSCCH, in addition to the location information of the second transmission related resource and the location information of the third transmission related resource. In this case, for example, in Figure 10 (a) and (b) of the above, if the transmitting UE can transmit / signal only the location information of the fourth transmission related resource to the receiving UE through the fourth (or last) transmission related PSCCH, the transmitting UE can set or specify the field / bit of the location information of the unused or remaining transmission resource to a preconfigured value (e.g., 0). For example, in Figure 10 (a) and (b) of the above, if the transmitting UE can transmit / signal only the location information of the fourth transmission related resource to the receiving UE through the fourth (or last) transmission related PSCCH, the transmitting UE can set or specify the field / bit of the location information of the unused or remaining transmission resource to a preconfigured state / bit value indicating / representing the last transmission (among 4 transmissions).

[0155] Further, for example, the transmitting UE can perform the reservation of the transmission resource based on a block. Specifically, for example, if the transmitting UE reserves K transmission resources, the transmitting UE can transmit the location information of the K transmission resources to the receiving UE through the SCI transmitted to the receiving UE at any (or specific) transmission time or time resource. That is, the SCI can include the location information of the K transmission resources. For example, if the transmitting UE reserves K transmission resources related to a specific TB, the transmitting UE can transmit the location information of the K transmission resources to the receiving UE through the SCI transmitted to the receiving UE at any (or specific) transmission time or time resource. That is, the SCI can include the location information of the K transmission resources. For example, Figure 10 (c) of the above shows a method of performing the block-based resource reservation by the transmitting UE by signaling the location information of 4 transmission resources to the receiving UE through one SCI in the case where the value K = 4.

[0156] For example, the SL DRX configuration can include one or more pieces / elements of the information listed below.

[0157] For example, the SL drx-onDurationTimer can be information related to a duration at the beginning of a DRX cycle. For example, the duration at the beginning of the DRX cycle can be information related to a duration in which the UE operates in an active mode to transmit or receive sidelink data.

[0158] For example, the SL drx-SlotOffset can be information related to a delay before the drx-onDurationTimer starts the DRX-onDurationTimer.

[0159] For example, the SL drx-InactivityTimer can be information indicating a duration after a PSCCH occasion in which a PSCCH indicates a new sidelink transmission and reception for a MAC entity. For example, when a transmitting UE indicates a PSSCH transmission through a PSCCH, the transmitting UE can operate in an active mode while the SL drx-InactivityTimer is operating / running, so that the transmitting UE can transmit the PSSCH to a receiving UE. Also, for example, when a receiving UE receives an indication that a transmitting UE transmits a PSSCH through a PSCCH, the receiving UE can operate in an active mode while the SL drx-InactivityTimer is operating / running, so that the receiving UE can receive the PSSCH from the transmitting UE.

[0160] For example, the SL drx-RetransmissionTimer can be information related to a maximum duration until a retransmission is received. For example, the SL drx-RetransmissionTimer can be configured for each HARQ process.

[0161] For example, the SL drx-LongCycleStartOffset information related to a long DRX cycle and a drx-StartOffset defining subframes where long and short DRX cycles start.

[0162] For example, the SL drx-ShortCycle can be information related to a short DRX cycle. For example, the SL drx-ShortCycle can be optional information.

[0163] For example, the SL drx-ShortCycleTimer can be information related to a duration in which the UE should follow a short DRX cycle. For example, the SL drx-ShortCycleTimer can be optional information.

[0164] For example, the SL drx-HARQ-RTT-Timer can be information related to a minimum duration before an allocation expected by the MAC entity for a HARQ retransmission. For example, the SL drx-HARQ-RTT-Timer can be configured for each HARQ process.

[0165] Meanwhile, for example, according to various embodiments of the present disclosure, when SL communication is performed based on an SL HARQ feedback operation (hereinafter, a NACK-only based SL HARQ feedback operation) that performs only NACK-based feedback, resetting / extension of an SL DRX timer and / or an active time can be performed. Here, for example, the SL HARQ feedback operation can include PSFCH transmission and / or PSFCH reception. For example, the NACK-only based SL HARQ feedback operation can be an operation that transmits NACK information to a TX UE only when the RX UE fails to decode / receive a PSSCH received from the TX UE.

[0166] According to an embodiment of the present disclosure, when a plurality of PSFCH transmissions overlap at the same time point, some or all of the plurality of PSFCH transmissions can be skipped / omitted. For example, from the perspective of a specific UE, when a plurality of PSFCH transmissions overlap at the same time point, some or all of the plurality of PSFCHs can be skipped / omitted based on the priority of PSSCH and / or SL data related to the PSFCH and the maximum number of PSFCHs that can be simultaneously transmitted by the UE.

[0167] For example, from the perspective of a specific UE, when PSFCH transmission and PSFCH reception overlap at the same time point, the PSFCH transmission or the PSFCH reception can be skipped / omitted based on the priority of PSSCH and / or SL data related to the PSFCH and the maximum number of PSFCHs that can be simultaneously transmitted by the UE.

[0168] For example, from the perspective of a specific UE, when PSFCH transmission and UL control / data transmission overlap at the same time point, the PSFCH transmission can be skipped / omitted based on the priority of PSSCH and / or SL data related to the PSFCH, the priority of UL control / data, and the maximum number of PSFCHs that can be simultaneously transmitted by the UE. Here, for example, the UL control / data can include an UL channel through which SL HARQ feedback, an SL BSR, and / or an SL SR is transmitted / piggybacked.

[0169] For example, from the perspective of a specific UE, when PSFCH reception and UL transmission overlap at the same point in time, the PSFCH reception can be skipped / omitted based on the priority of PSSCH and / or SL data related to the PSFCH, the priority of UL control / data, and the maximum number of PSFCHs that can be simultaneously transmitted by the UE. Here, for example, the UL control / data can include an UL channel through which SL HARQ feedback, an SL BSR, and / or an SL SR are transmitted / piggybacked.

[0170] For example, from the perspective of a specific UE, when transmission / reception of an NR PSFCH and transmission / reception of an LTE SL channel / signal (e.g., PSCCH, PSSCH, SL synchronization signal) overlap at the same point in time, the NR PSFCH transmission / reception can be skipped / omitted based on the priority of NR PSSCH and / or NR SL data related to the NR PSFCH, the priority of the LTE SL channel / signal, and the maximum number of PSFCHs that can be simultaneously transmitted by the UE.

[0171] For example, when a RX UE performing an SL DRX operation performs a PSFCH transmission operation based on a NACK-only, if NACK transmission is skipped / omitted due to one of the above examples, the TX UE can assume that the RX UE has successfully received the MAC PDU and can not perform an additional retransmission operation. However, at this time, since the RX UE has not successfully received the MAC PDU, there can be a problem in resetting / lengthening of the SL DRX timer and / or the active time. Here, for example, since whether to perform resetting / lengthening of the SL DRX timer and / or the active time of the RX UE is determined based on whether the reception / decoding of the MAC PDU has failed, not on whether the NACK has actually been transmitted through the PSFCH, the problem can occur. To solve this problem, various embodiments of the disclosure described later can be applied.

[0172] For example, when the NACK-only based SL HARQ feedback operation is performed, the RX UE performing the SL DRX operation can perform the resetting / extension of the SL DRX timer and / or the active time only when the NACK transmission is actually performed through the PSFCH resource. For example, when the NACK-only based PSFCH transmission operation is performed in the groupcast, the RX UE performing the SL DRX operation can perform the resetting / extension of the SL DRX timer and / or the active timer related to the SL HARQ process with respect to the NACK transmission only when the NACK transmission is actually performed through the PSFCH resource. For example, in the NACK-only based SL HARQ feedback operation, when the NACK transmission is skipped / omitted, the RX UE can not perform the resetting / extension of the SL DRX timer and / or the active time related to the SL HARQ process with respect to the NACK transmission.

[0173] Further, for example, on the other hand, in the case where the ACK / NACK based SL HARQ feedback operation is performed, the RX UE performing the SL DRX operation can perform the resetting / extension of the SL DRX timer and / or the active time when it fails to receive / decode the MAC PDU regardless of whether the actual NACK is transmitted through the PSFCH resource. Here, for example, the ACK / NACK based SL HARQ feedback operation can include an operation of transmitting ACK information to the TX UE when the RX UE successfully decodes / receives the PSSCH received from the TX UE, and an operation of transmitting NACK information to the TX UE when the RX UE fails to decode / receive the PSSCH. For example, when the ACK / NACK based SL HARQ feedback operation is performed in the groupcast, even if the PSFCH transmission is skipped / omitted, if the RX UE performing the SL DRX operation fails to receive / decode the MAC PDU related to the PSFCH transmission, the RX UE can perform the resetting / extension of the SL DRX timer and / or the active time related to the SL HARQ process with respect to the PSFCH transmission. Further, for example, when the ACK / NACK based SL HARQ feedback operation is performed, even if the PSFCH transmission (e.g., ACK or NACK) is skipped / omitted, the RX UE performing the SL DRX operation can perform the resetting / extension of the SL DRX timer and / or the active time. Here, for example, when the ACK / NACK based SL HARQ feedback operation is performed, even if the RX UE skips or omits the PSFCH transmission, since the TX UE regards it as DTX and / or NACK and performs retransmission, there can be no problem in which the RX UE performs the retransmission reception operation meaninglessly for the duration in which there is no retransmission of the UE.

[0174] According to an embodiment of the disclosure, the RX UE performing the NACK-only based SL HARQ feedback operation can skip / omit the NACK transmission due to a relatively high priority SL channel / signal reception operation. In this case, for example, after the RX UE checks / detects whether the NACK transmission of another UE is performed on the PSFCH resource, if the NACK transmission of another UE is performed, although the RX UE itself does not perform the NACK transmission, the SL DRX timer and / or the active time resetting / extension operation can be performed. For example, the SL channel / signal can include at least one of a PSFCH or an LTE SL channel / signal. For example, the LTE SL channel / signal can include at least one of a PSSCH, a PSCCH, or an SL synchronization signal.

[0175] For example, when the above-described embodiment of the disclosure is applied, as one of examples in which the transmission overlaps, the RX UE performing the NACK-only based SL HARQ feedback operation can skip / omit the NACK transmission due to a relatively high priority SL channel / signal reception operation. In this case, for example, on the PSFCH resource related to the NACK transmission, it can be checked / detected whether the NACK transmission by another member UE in the same groupcast is performed. At this time, if the NACK transmission of another member UE is performed, although the RX UE itself does not perform the NACK transmission, the resetting / extension operation of the SL DRX timer and / or the active time related to the SL HARQ process with respect to the NACK transmission can be performed.

[0176] According to an embodiment of the disclosure, the UE performing the SL DRX operation can consider the PSFCH transmission operation satisfying the following specific condition to be higher in priority than other PSFCH reception operations. For example, the RX UE performing the SL DRX operation can consider the PSFCH transmission and / or PSFCH reception operation satisfying the following specific condition to be higher in priority than other PSFCH reception and / or transmission operations. Here, for example, the other PSFCH reception and / or transmission can be a PSFCH reception and / or transmission related to a preconfigured service type. For example, the other PSFCH reception and / or transmission can be a PSFCH reception and / or transmission related to a priority of an LCH or a service higher than a preconfigured threshold level. For example, the other PSFCH reception and / or transmission can be a PSFCH reception and / or transmission related to a QoS requirement (e.g., reliability, latency) higher than a preconfigured threshold level. For example, the other PSFCH reception and / or transmission can be a PSFCH reception and / or transmission related to a QoS requirement (e.g., reliability, latency) lower than a preconfigured threshold level.

[0177] For example, a RX UE performing SL DRX operation can consider PSFCH transmission and / or PSFCH reception operation satisfying the following specific condition as having higher priority than UL control / data transmission and / or reception operation. Here, for example, UL control / data can include UL channels through which SL HARQ feedback, SL BSR, and / or SL SR is transmitted / piggybacked.

[0178] For example, a RX UE performing SL DRX operation can consider PSFCH transmission and / or PSFCH reception operation satisfying the following specific condition as having higher priority than transmission / reception operation for LTE SL channels / signals (e.g., PSCCH, PSSCH, SL synchronization signal).

[0179] For example, the specific condition can be related to SL HARQ feedback based on NACK only. For example, when a RX UE transmits and / or receives SL HARQ feedback based on NACK only in a groupcast, the RX UE can determine that the transmission and / or reception has higher priority than other PSFCH transmission and / or reception operation.

[0180] For example, the specific condition can be related to SL HARQ feedback based on ACK / NACK. For example, when a RX UE transmits and / or receives SL HARQ feedback based on ACK / NACK in a groupcast, the RX UE can determine that the transmission and / or reception has higher priority than other PSFCH transmission and / or reception operation.

[0181] For example, the specific condition can be related to SL HARQ feedback transmission and / or reception. For example, when a RX UE transmits and / or receives SL HARQ feedback, the RX UE can determine that the transmission and / or reception has higher priority than other PSFCH transmission and / or reception operation.

[0182] For example, the specific condition can be related to groupcast communication. For example, when a RX UE performs transmission and / or reception of PSFCH related to groupcast communication, the RX UE can determine that the transmission and / or reception has higher priority than other PSFCH transmission and / or reception operation. Here, for example, SL channel / signal transmission and / or reception (e.g., PSFCH transmission) related to groupcast including a relatively large number of members can be considered as having higher priority than transmission and / or reception related to other groupcast. For example, SL channel / signal transmission and / or reception (e.g., PSFCH transmission) related to groupcast including a larger number of members than a preconfigured threshold can be considered as having higher priority than transmission / reception related to another groupcast, unicast, or broadcast.

[0183] For example, the specific condition can be related to unicast communication. For example, when the RX UE performs transmission and / or reception of PSFCH related to unicast communication, the RX UE can determine that the transmission and / or reception has higher priority than other PSFCH transmission and / or reception operation.

[0184] For example, the specific condition can be related to broadcast communication. For example, when the RX UE performs transmission and / or reception of PSFCH related to broadcast communication, the RX UE can determine that the transmission and / or reception has higher priority than other PSFCH transmission and / or reception operation.

[0185] For example, the specific condition can be related to PSFCH transmission and / or reception of a pre-configured service type. For example, the specific condition can be related to PSFCH transmission and / or reception with a priority of LCH or service higher than a pre-configured threshold level. For example, the specific condition can be related to PSFCH transmission and / or reception with a QoS requirement (e.g., reliability, latency) higher than a pre-configured threshold level. For example, the specific condition can be related to PSFCH transmission and / or reception with a QoS requirement (e.g., reliability, latency) lower than a pre-configured threshold level.

[0186] According to embodiments of the disclosure, the following embodiments can be applied to a RX UE performing SL DRX operation on a reserved resource (hereinafter, RSR_RSC) located after SL DRX timer and / or active time expiration or end. For example, the RSR_RSC can be a reserved resource signaled by a previous SCI. For example, the RSR_RSC can be a reserved resource located after SL DRX timer and / or active time expiration or end related to a SL HARQ process. Here, for example, the above-described embodiments of the disclosure can be applied when the RX UE skips / omits related PSFCH transmission for a MAC PDU received on a reserved resource before the RSR_RSC. For example, the above-described embodiments of the disclosure can be applied when the RX UE skips / omits related PSFCH transmission (e.g., ACK information transmission) due to a relatively high priority channel transmission and / or reception operation for a MAC PDU successfully received on a reserved resource before the RSR_RSC. For example, the reserved resource before the RSR_RSC can be a reserved resource before SL DRX timer expiration or end related to a SL HARQ process. For example, the reserved resource before the RSR_RSC can be a reserved resource within an active time interval / duration related to a SL HARQ process. For example, the above-described embodiments of the disclosure can be applied when the RX UE actually successfully receives PSCCH and / or PSSCH retransmission from the TX UE on the RSR_RSC.

[0187] For example, when the embodiments of the disclosure are applied, for the MAC PDU that has been successfully received by the RX UE, the TX UE can consider it as DTX and / or NACK and perform retransmission, thereby mitigating the problem of performing excessive or meaningless retransmission. For example, when the embodiments of the disclosure are applied, the RX UE can skip / omit the PSFCH transmission for the successfully received MAC PDU, and the TX UE can consider it as DTX and / or NACK and perform retransmission, thereby mitigating the problem of performing excessive or meaningless retransmission. For example, when the embodiments of the disclosure are applied, if the TX UE does not successfully receive the PSFCH of the ACK information actually transmitted by the RX UE, the TX UE can consider it as DTX and / or NACK and perform retransmission, thereby mitigating the problem of performing excessive or meaningless retransmission.

[0188] For example, the disclosure can be applied to at least one of the following cases: a case in which the RX UE performs ACK / NACK-based SL HARQ feedback operation; a case in which a packet related to an LCH or a service having a priority higher than a preconfigured threshold level is transmitted; a case in which a packet related to an LCH or a service having a priority lower than a preconfigured threshold level is transmitted; a case in which a packet related to a QoS requirement (e.g., delay, reliability, minimum communication range) higher than a preconfigured threshold is transmitted; a case in which a packet related to a QoS requirement (e.g., delay, reliability, minimum communication range) lower than a preconfigured threshold is transmitted; a case in which the degree of congestion in a resource pool (e.g., CBR) is higher than a preconfigured threshold; and / or a case in which the degree of congestion in a resource pool (e.g., CBR) is lower than a preconfigured threshold.

[0189] For example, the RX UE can additionally perform PSSCH and / or PSCCH decoding on the RSR_RSC and then transmit ACK information related to the PSFCH resource related to the RSR_RSC. For example, the ACK information can always be transmitted on the PSFCH resource related to the RSR_RSC after the RX UE additionally performs PSSCH and / or PSCCH decoding related to the TX UE in the slot related to the RSR_RSC. For example, the RX UE additionally performs PSSCH and / or PSCCH decoding related to the TX UE on the slot related to the RSR_RSC and then, based on whether the actual PSSCH and / or PSCCH decoding is successful, ACK / NACK information can be transmitted on the PSFCH resource related to the RSR_RSC. For example, the additional PSSCH and / or PSCCH decoding can be performed in the frequency domain related to the RSR_RSC. For example, the additional PSSCH and / or PSCCH decoding can be performed for all frequency domains within the resource pool.

[0190] Here, for example, when PSCCH and / or PSSCH related to another TX UE is detected / decoded on the slot related to the RSR_RSC, the RX UE can not reset / extend the SL DRX timer and / or the active time of the SL HARQ procedure related to the PSCCH and / or PSSCH.

[0191] Here, for example, when PSCCH and / or PSSCH related to another TX UE is detected / decoded on the slot related to the RSR_RSC, the RX UE can reset / extend the SL DRX timer and / or the active time of the SL HARQ procedure related to the PSCCH and / or PSSCH.

[0192] For example, the RX UE does not additionally perform PSSCH and / or PSCCH decoding on the RSR_RSC and the RX UE can transmit ACK information on the PSFCH resource related to the RSR_RSC. For example, the RX UE can not additionally perform PSSCH and / or PSCCH decoding related to the TX UE on the RSR_RSC related slot with respect to the RSR_RSC related frequency domain and the RX UE can transmit ACK information on the PSFCH resource related to the RSR_RSC. For example, the RX UE can not additionally perform PSSCH and / or PSCCH decoding related to the TX UE on the RSR_RSC related slot with respect to all frequency domains within the resource pool and the RX UE can transmit ACK information on the PSFCH resource related to the RSR_RSC.

[0193] For example, the number of RSR_RSCs in which the RX UE performs PSFCH transmission and / or ACK information transmission can be configured differently or independently based on the service type, priority, and / or congestion level in the resource pool. Here, for example, the number of RSR_RSCs can be a maximum number. For example, the number of RSR_RSCs can be a minimum number. For example, the number of RSR_RSCs can be an average number.

[0194] Further, for example, whether the RX UE applies the various embodiments of the present disclosure described above is configured based on whether the TX UE is a UE performing SL DRX operation; whether the TX UE is a power saving UE; whether the RX UE performs PSFCH transmission related to a MAC PDU successfully received on a reserved resource before expiry of a SL DRX timer related to a SL HARQ process with RSR_RSC; and / or whether the RX UE performs ACK information transmission related to a MAC PDU successfully received on a reserved resource before expiry of a SL DRX timer related to a SL HARQ process with RSR_RSC.

[0195] For example, the RX UE can apply the various embodiments of the present disclosure described above when the TX UE is a UE performing SL DRX operation and / or a power saving UE. For example, the various embodiments of the present disclosure provided can not be applied to the RX UE when the RX UE actually transmits ACK information for a MAC PDU successfully received on a reserved resource before expiry of a SL DRX timer related to a SL HARQ process with RSR_RSC. For example, the various embodiments of the present disclosure can not be applied to the RX UE when the RX UE actually transmits ACK information for a MAC PDU successfully received on a reserved resource within an active time interval / duration related to a SL HARQ process before RSR_RSC.

[0196] For example, whether or not various embodiments of the present disclosure are applied can be determined based on at least one of the following elements / parameters, including: a service type; an LCH-related priority; a service-related priority; a QoS requirement (e.g., delay, reliability, minimum communication range); a PQI parameter; an LCH / MAC PDU transmission with HARQ feedback enabled; an LCH / MAC PDU transmission with HARQ feedback disabled; a CBR measurement of a resource pool; an SL broadcast type (e.g., unicast, groupcast, broadcast); an SL groupcast HARQ feedback option (e.g., a feedback based on only NACK, a feedback based on ACK / NACK, a TX-RX distance-based only NACK feedback); an SL mode 1 CG type (e.g., SL CG type 1, SL CG type 2); an SL mode type (e.g., mode 1, mode 2); a resource pool; whether or not a PSFCH resource is a configured resource pool; a source ID; a destination ID; a source L2 ID; a destination L2 ID; a PC5 RRC connection link; an SL link; a connection state with a base station (e.g., an RRC CONNECTED state, an IDLE state, an INACTIVE state); an SL HARQ process; an SL HARQ process ID; whether or not a TX UE or a RX UE performs an SL DRX operation; whether or not it corresponds to a power saving UE; whether or not a PSFCH TX and a PSFCH RX overlap from a perspective of a specific UE; whether or not multiple PSFCH TXs overlap beyond a UE capability; whether or not a PSFCH TX and / or a PSFCH RX is omitted; whether or not a RX UE actually successfully receives a PSCCH and / or a PSSCH (re)transmission from a TX UE.

[0197] For example, the parameter setting values related to various embodiments of the disclosure can be determined based on at least one of the following elements / parameters, including: a service type; an LCH-related priority; a service-related priority; a QoS requirement (e.g., delay, reliability, minimum communication range); a PQI parameter; an LCH / MAC PDU transmission with HARQ feedback enabled; an LCH / MAC PDU transmission with HARQ feedback disabled; a CBR measurement of a resource pool; an SL broadcast type (e.g., unicast, groupcast, broadcast); an SL groupcast HARQ feedback option (e.g., a feedback based on only NACK, a feedback based on ACK / NACK, a TX-RX distance-based only NACK feedback); an SL mode 1 CG type (e.g., SL CG type 1, SL CG type 2); an SL mode type (e.g., mode 1, mode 2); a resource pool; whether a PSFCH resource is a configured resource pool; a source ID; a destination ID; a source L2 ID; a destination L2 ID; a PC5 RRC connection link; an SL link; a connection state with a base station (e.g., an RRC CONNECTED state, an IDLE state, an INACTIVE state); an SL HARQ process; an SL HARQ process ID; whether a TX UE or a RX UE performs an SL DRX operation; whether it corresponds to a power saving UE; whether PSFCH TX and PSFCH RX are overlapped from a certain UE perspective; whether multiple PSFCH TXs beyond UE capability are overlapped; whether PSFCH TX and / or PSFCH RX are omitted; whether a RX UE actually successfully receives a PSCCH and / or PSSCH (re)transmission from a TX UE.

[0198] In addition, in various embodiments of the disclosure, for example, "configuration" or "designation" can mean that a base station notifies a UE through a pre-defined channel / signal (e.g., SIB, RRC, MAC CE). For example, "configuration" or "designation" can mean a format provided through PRE-CONFIGURATION. For example, "configuration" or "designation" can be a format in which a UE notifies other UEs through a pre-defined channel / signal (e.g., SL MAC CE, PC5 RRC). Here, for example, the channel / signal can include a channel / signal for a physical layer or a higher layer.

[0199] Further, in various embodiments of the disclosure, for example, "PSFCH" can be replaced with at least one of NR PSSCH, NRPSCCH, NR SL SSB, LTE PSSCH, LTE PSCCH, LTE SL SSB, and UL channel / signal.

[0200] Further, various embodiments of the disclosure can be combined with each other.

[0201] In various embodiments of the disclosure, the above SL DRX timers can be used for the following purposes.

[0202] For example, the SL DRX on-duration timer can be used in a period in which a UE in which the SL DRX operation is performed basically needs to operate as an active time in order to receive PSCCH / PSSCH of the counterpart / peer UE.

[0203] For example, the SL DRX inactivity timer can be used in a period in which the SL DRX on-duration period is extended, which is a period in which a UE in which the SL DRX operation is performed basically needs to operate as an active time in order to receive PSCCH / PSSCH of the counterpart / peer UE. That is, for example, the SL DRX on-duration timer can be extended by the SL DRX inactivity timer period. Further, when the UE receives a new packet (e.g., a new PSSCH) from the counterpart / peer UE, the UE can start the SL DRX inactivity timer to extend the SL DRX on-duration timer.

[0204] For example, the SL DRX HARQ RTT timer can be used in a sleep mode operation period until a UE performing the SL DRX operation receives a retransmission packet (or a PSSCH allocation) transmitted from the counterpart / peer UE. That is, for example, when the UE starts the SL DRX HARQ RTT timer, the UE can determine that the counterpart / peer UE will not transmit a sidelink retransmission packet to itself until the SL DRX HARQ RTT timer expires, and thus, the UE can operate in a sleep mode during the corresponding timer.

[0205] For example, the SL DRX retransmission timer can be used in an active time period in which a UE performing the SL DRX operation receives a retransmission packet (or a PSSCH allocation) transmitted from the counterpart / peer UE. For example, during the SL DRX retransmission timer period, the UE can monitor reception of a retransmission sidelink packet (or a PSSCH allocation) transmitted by the counterpart / peer UE.

[0206] Further, in the disclosure, for example, an on-duration or “On duration” can be an active duration (i.e., a duration of operating in a wake-up state (RF module is “on”) to receive / transmit a wireless signal). For example, an off-duration or “Off duration” can be a sleep duration for power saving (i.e., a duration of operating in a sleep mode (RF module “off”), wherein a transmitting UE can not operate in the sleep mode during the sleep duration, and wherein if necessary, it can be allowed to operate as an active time operation for a moment for sensing operation / transmission operation even in the sleep time).

[0207] In the disclosure, for example, a “specific time” can be a time in which a UE operates in an active time for a predetermined time in order to receive a sidelink signal or sidelink data from an opposite / peer UE. For example, the “specific time” can be a time in which a UE operates in an active time as long as a timer (e.g., a SL DRX retransmission timer, a SL DRX inactivity timer, a timer capable of operating as an active time in a DRX operation of a RX UE) time in order to receive a sidelink signal or sidelink data from an opposite / peer UE.

[0208] Figure 11 A procedure in which a receiving UE starts a SL DRX related timer according to an embodiment of the disclosure is illustrated. Figure 11 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0209] Reference Figure 11 In step S1110, the receiving UE can obtain a SL DRX configuration. For example, the receiving UE can receive the SL DRX configuration from a base station. For example, the receiving UE can receive the SL DRX configuration from a transmitting UE. For example, the SL DRX configuration can include information related to a period related to SL DRX and information related to a SL DRX related timer. For example, the SL DRX related timer can include at least one of a SL DRX on-duration timer, a SL DRX deactivation timer, a SL DRX HARQ RTT timer, or a SL DRX retransmission timer.

[0210] In step S1120, the receiving UE can receive, from the transmitting UE, a first SCI for scheduling a first PSSCH through a first PSCCH.

[0211] In step S1130, the receiving UE can receive the second SCI and the first data from the transmitting UE over the first PSSCH. For example, the receiving UE can determine the first PSFCH resource based on the index of the slot and the index of the subchannel related to the first PSSCH.

[0212] In step S1140, the receiving UE can skip / omit the transmission of the first PSFCH related to the first PSSCH. For example, when multiple PSFCH transmissions overlap on the same time point, based on the priority of the SL data related to the PSFCH and the maximum number of PSFCHs the receiving UE is able to transmit simultaneously, at least one PSFCH transmission can be skipped / omitted from among the multiple PSFCH transmissions. For example, the at least one PSFCH transmission can include the first PSFCH transmission.

[0213] For example, when the first PSFCH transmission and the PSFCH reception overlap on the same time point, based on the priority of the SL data related to the PSFCH and the maximum number of PSFCHs the receiving UE is able to transmit simultaneously, the first PSFCH transmission can be skipped / omitted.

[0214] For example, when the first PSFCH transmission and the UL control / data transmission overlap on the same time point, based on the priority of the SL data related to the PSFCH, the priority related to the UL transmission, and the maximum number of PSFCHs the receiving UE is able to transmit simultaneously, the first PSFCH transmission can be skipped / omitted. Here, for example, the UL transmission can include an UL channel over which SL HARQ feedback, SL BSR, and / or SL SR is transmitted / piggybacked.

[0215] In step S1150, based on skipping / omitting the first PSFCH transmission related to the first PSSCH on the first PSFCH resource, the receiving UE can start a first timer included in the SL DRX configuration.

[0216] For example, the first PSFCH can include an ACK or include a NACK.

[0217] For example, the first timer can include at least one of a SL DRX HARQ RTT timer or a SL DRX retransmission timer.

[0218] For example, based on a reserved resource located after the expiration of the first timer, the receiving UE can transmit an ACK to the transmitting UE.

[0219] For example, decoding of the first PSSCH can be additionally performed on the reserved resource located after the expiration of the first timer. For example, based on the successful decoding, the receiving UE can transmit an ACK to the transmitting UE.

[0220] For example, the number of reserved resources located after the expiration of the first timer can be configured differently based on at least one of a service type, a priority, or congestion in a resource pool.

[0221] Figure 12 Another procedure in which a receiving UE starts SL DRX related timers is shown in accordance with embodiments of the disclosure. Figure 12 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0222] Reference Figure 12 In step S1210, the receiving UE can obtain a SL DRX configuration. For example, the receiving UE can receive the SL DRX configuration from a base station. For example, the receiving UE can receive the SL DRX configuration from a transmitting UE. For example, the SL DRX configuration can include information related to a period related to SL DRX and information related to SL DRX related timers. For example, the SL DRX related timers can include at least one of a SL DRX on-duration timer, a SL DRX inactivity timer, a SL DRX HARQ RTT timer, or a SL DRX retransmission timer.

[0223] In step S1220, the receiving UE can receive, from the transmitting UE, a first SCI for scheduling a first PSSCH through a first PSCCH. The receiving UE can receive, from the transmitting UE, a second SCI and first data through the first PSSCH. For example, the receiving UE can determine a first PSFCH resource based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, the receiving UE can perform ACK / NACK based HARQ feedback through the first PSFCH.

[0224] In step S1230, the receiving UE can receive, from the transmitting UE, a third SCI for scheduling a second PSSCH through a second PSCCH. The receiving UE can receive, from the transmitting UE, a fourth SCI and second data through the second PSSCH. For example, the receiving UE can determine a second PSFCH resource based on an index of a slot and an index of a subchannel related to the second PSSCH. For example, the receiving UE can perform NACK only based HARQ feedback through the second PSFCH.

[0225] In step S1240, the receiving UE can skip / omit the first PSFCH transmission related to the first PSSCH, and the receiving UE can skip / omit the second PSFCH transmission related to the second PSSCH. In this case, for example, as in the example of step S1140 described above, the first PSFCH transmission can be skipped / omitted. For example, as in the example of step S1140 described above, the second PSFCH transmission can be skipped / omitted.

[0226] In step S1250, the receiving UE can start a first timer included in the SL DRX configuration based on skipping / omitting a first PSFCH transmission related to the first PSSCH on the first PSFCH resource. For example, the receiving UE can not start a second timer included in the SL DRX configuration based on skipping / omitting a second PSFCH transmission related to the second PSSCH on the second PSFCH resource. For example, the first PSFCH can include an ACK or a NACK. For example, the second PSFCH can include only a NACK. For example, the first timer can include at least one of a SL DRX HARQ RTT timer or a SL DRX retransmission timer. For example, the second timer can include at least one of a SL DRX HARQ RTT timer or a SL DRX retransmission timer.

[0227] In step S1260, the receiving UE can start the second timer based on a third PSFCH transmission related to the second data by another UE. For example, the another UE can be a UE performing the same groupcast communication as the receiving UE. For example, the third PSFCH can include only a NACK. For example, step S1260 can be skipped / omitted if the third PSFCH transmission related to the second data is not performed by the another UE.

[0228] For example, the receiving UE can send an ACK to the transmitting UE based on the reserved resource located after the expiration of the first timer.

[0229] For example, the decoding of the first PSSCH can be additionally performed on the reserved resource located after the expiration of the first timer. For example, the receiving UE can send an ACK to the transmitting UE based on the successful decoding.

[0230] For example, the number of the reserved resources located after the expiration of the first timer can be differently configured based on at least one of a service type, a priority, or a congestion in a resource pool.

[0231] Figure 13 An example in which a receiving UE is located in a reserved resource after the expiration of a SL DRX related timer according to an embodiment of the disclosure is illustrated. Figure 12 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0232] Reference Figure 13When the receiving UE skips / omits the first PSFCH transmission for the first data received from the transmitting UE, the receiving UE can start a first SL DRX timer related to the first PSFCH transmission. For example, the first SL DRX timer can be at least one of a SL DRX HARQ RTT timer or a SL DRX retransmission timer. For example, the first SL DRX active time can be an active time related to the first SL DRX timer.

[0233] At this time, for example, in ACK / NACK-based HARQ feedback, when the receiving UE skips / omits the first PSFCH transmission (e.g., SL HARQ ACK or SL HARQ NACK), the transmitting UE can determine the first data related to the first PSFCH as a discontinuous detection (DTX). In addition, for example, after the first SL DRX timer expires, the receiving UE can transmit an ACK for the first data to the transmitting UE based on a reserved resource. Or, for example, the receiving UE performs decoding of the first data on the reserved resource, and if the decoding is successfully performed, the receiving UE can transmit an ACK for the first data to the transmitting UE based on the reserved resource after the SL DRX timer expires.

[0234] Here, for example, the reserved resource can be located within a second SL DRX active time. For example, the second SL DRX active time can be an active time for SL communication between the receiving UE and another UE, or an active time for transmitting and receiving data different from the first data.

[0235] For example, when a PSCCH and / or a PSSCH related to another transmitting UE is detected on the reserved resource, the receiving UE can not start the first SL DRX timer.

[0236] In addition, for example, if the receiving UE does not transmit a PSFCH for enabling a HARQ transmission, the receiving UE can still start a HARQ RTT timer in a symbol or a slot after the end of the PSFCH resource. For example, due to UL / SL prioritization, the receiving UE can not transmit the PSFCH.

[0237] In addition, for example, in NACK-only-based HARQ feedback of groupcast communication, if a PSFCH transmission (e.g., NACK) is dropped, a SL DRX retransmission timer can not be started. Here, for example, the PSFCH transmission can be dropped due to UL / SL prioritization.

[0238] Figure 14 A method in which a first device starts a SL DRX related timer according to an embodiment of the disclosure is illustrated. Figure 14Embodiments of the first device 100 can be combined with various embodiments of the present disclosure.

[0239] Referring to Figure 14 In step S1410, the first device 100 can obtain a SL sidelink discontinuous reception (SL DRX) configuration.

[0240] In step S1420, the first device 100 can receive, from the second device 200, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH).

[0241] In step S1430, the first device 100 can receive, from the second device 200, second SCI and first data through the first PSSCH.

[0242] In step S1440, based on an index of a slot and an index of a subchannel related to the first PSSCH, the first device 100 can determine a first physical sidelink feedback channel (PSFCH) resource.

[0243] For example, based on skipping / omitting a PSFCH transmission related to the first PSSCH on the first PSFCH resource, a first timer included in the SL DRX configuration can be started.

[0244] For example, the first PSFCH can include an acknowledgement (ACK) or a negative acknowledgement (NACK).

[0245] For example, the first timer can include at least one of a SL DRX hybrid automatic repeat request (HARQ) round trip time (RTT) timer or a SL DRX retransmission timer.

[0246] For example, the first device 100 can receive, through a second PSCCH, third SCI for scheduling a second PSSCH. For example, the first device 100 can receive, through the second PSSCH, fourth SCI and second data. For example, based on an index of a slot and an index of a subchannel related to the second PSSCH, the first device 100 can determine a second PSFCH resource. For example, based on skipping / omitting a second PSFCH transmission related to the second PSSCH on the second PSFCH resource, a second timer included in the SL DRX configuration can not be started. For example, the second PSFCH can include only a NACK. For example, the second timer can include at least one of a SL DRX HARQ RTT timer and a SL DRX retransmission timer.

[0247] For example, the second timer can be started based on transmission of a third PSFCH related to the second data by a third device. For example, the third device can be a device performing the same groupcast communication as the first device.

[0248] For example, the ACK can be transmitted based on the reserved resource located after the expiration of the first timer.

[0249] For example, the decoding of the first PSSCH can be additionally performed on the reserved resource located after the expiration of the first timer. For example, the ACK can be transmitted based on the successful decoding.

[0250] For example, the number of the reserved resource located after the expiration of the first timer can be differently configured based on at least one of a service type, a priority, or congestion in a resource pool.

[0251] For example, the second PSFCH transmission can be skipped / omitted based on a priority of a third PSFCH transmission overlapping the second PSFCH transmission being higher than a priority of the second PSFCH transmission. For example, the second PSFCH transmission and the third PSFCH transmission can be related to a groupcast communication. For example, a number of groupcast members related to the third PSFCH transmission can be greater than a number of groupcast members related to the second PSFCH transmission.

[0252] The above-described embodiments can be applied to various devices to be described below. For example, the processor 102 of the first device 100 can obtain a sidelink discontinuous reception (SL DRX) configuration. Also, for example, the processor 102 of the first device 100 is configured to control the transceiver 106 to receive, from 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). Also, for example, the processor 102 of the first device 100 is configured to control the transceiver 106 to receive, from the second device, second SCI and first data through the first PSSCH. Based on an index of a slot and an index of a subchannel related to the first PSSCH, the processor 102 of the first device 100 is configured to control the transceiver 106 to determine a first physical sidelink feedback channel (PSFCH) resource. For example, a first timer included in the SL DRX configuration is started based on skipping of a first PSFCH transmission related to the first PSSCH on the first PSFCH resource.

[0253] According to embodiments of the present disclosure, a first device for performing wireless communication can be provided. For example, the first device can include one or more memories to store 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 execute the instructions to obtain a sidelink discontinuous reception (SL DRX) configuration, receive, from 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), receive, from the second device, second SCI and first data through the first PSSCH, and determine a first physical sidelink feedback channel (PSFCH) resource based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource, a first timer included in the SL DRX configuration is started.

[0254] According to embodiments of the present disclosure, a device configured to control a first UE can be provided. For example, one or more processors; and one or more memories operably coupled with the one or more processors and storing instructions. For example, the one or more processors execute the instructions to obtain a sidelink discontinuous reception (SL DRX) configuration, receive, from a second UE, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH), receive, from the second UE, second SCI and first data through the first PSSCH, and determine a first physical sidelink feedback channel (PSFCH) resource based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, wherein based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource, a first timer included in the SL DRX configuration is started.

[0255] According to embodiments of the present disclosure, a non-transitory computer-readable medium (CRM) storing instructions can be provided. For example, when the instructions are executed, cause a first device to obtain a sidelink discontinuous reception (SL DRX) configuration, receive, from 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), receive, from the second device, second SCI and first data through the first PSSCH, and determine a first physical sidelink feedback channel (PSFCH) resource based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource, a first timer included in the SL DRX configuration is started.

[0256] Figure 15 A method for starting a SL DRX timer according to an embodiment of the disclosure is illustrated. Figure 15 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0257] Reference Figure 15 In step S1510, the second device 200 can transmit, to the first device 100, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH).

[0258] In step S1520, the second device 200 can transmit, to the first device 100, the second SCI and the first data through the first PSSCH.

[0259] For example, a SL sidelink discontinuous reception (DRX) configuration can be obtained.

[0260] For example, a first physical sidelink feedback channel (PSFCH) resource can be determined based on an index of a slot and an index of a subchannel related to the first PSSCH.

[0261] For example, based on skipping / omitting a first PSFCH transmission related to the first PSSCH on the first PSFCH resource, a first timer included in the SL DRX configuration can be started.

[0262] For example, the first PSFCH can include an acknowledgement (ACK) or a negative acknowledgement (NACK).

[0263] For example, the first timer can include at least one of a SL DRX hybrid automatic repeat request (HARQ) round trip time (RTT) timer or a SL DRX retransmission timer.

[0264] For example, the ACK can be transmitted based on a reserved resource located after an expiry of the first timer.

[0265] For example, a decoding of the first PSSCH can be additionally performed on the reserved resource located after the expiry of the first timer. For example, the ACK can be transmitted based on a successful decoding.

[0266] For example, a number of the reserved resources located after the expiry of the first timer can be differently configured based on at least one of a service type, a priority, or congestion in a resource pool.

[0267] The above-described embodiments can be applied to various devices to be described below. First, for example, the processor 202 of the second device 200 can be configured to control the transceiver 206 to transmit, to the first device 100, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH). Also, for example, the processor 202 of the second device 200 can be configured to control the transceiver 206 to transmit, to the first device 100, second SCI and first data through the first PSSCH.

[0268] According to embodiments of the disclosure, a second device for performing wireless communication can be provided. For example, the second device can include one or more memories storing instructions, one or more transceivers, and one or more processors connected with the one or more memories and the one or more transceivers. For example, the one or more processors execute the instructions to transmit, to a first device, first sidelink control information (SCI) for scheduling a first physical sidelink shared channel (PSSCH) through a first physical sidelink control channel (PSCCH), and transmit, to the first device, second SCI and first data through the first PSSCH. For example, a sidelink discontinuous reception (SL DRX) configuration is obtained. For example, a first physical sidelink feedback channel (PSFCH) resource is determined based on an index of a slot and an index of a subchannel related to the first PSSCH. For example, a first timer included in the SL DRX configuration is started based on skipping a first PSFCH transmission related to the first PSSCH on the first PSFCH resource.

[0269] Various embodiments of the disclosure can be combined with each other.

[0270] Various embodiments of the disclosure can be independently implemented. Alternatively, various embodiments of the disclosure can be combined or merged with each other to be implemented. For example, for ease of description, various embodiments of the disclosure have been described based on a 3GPP system, but various embodiments of the disclosure can be extended to systems other than the 3GPP system. For example, various embodiments of the disclosure are not limited to direct communication between UEs, and can be used in uplink or downlink, and in this case, a base station or a relay node can use the method proposed according to various embodiments of the disclosure. For example, information about whether to apply the method according to various embodiments of the disclosure can be provided by a base station to a UE or by a second device 200 to a receiving UE using a predefined signal (e.g., a physical layer signal or a higher layer signal). For example, information related to the rule according to various embodiments of the disclosure can be defined such that the base station can notify a terminal or the second device 200 of a receiving UE through a predefined signal (e.g., a physical layer signal or a higher layer signal).

[0271] Hereinafter, a device to which various embodiments of the disclosure can be applied will be described.

[0272] Various descriptions, functions, processes, proposals, methods, and / or operation flows of the disclosure described herein can be applied to, but are not limited to, various fields requiring wireless communication / connection between devices (e.g., 5G).

[0273] Hereinafter, a description will be given in more detail with reference to the accompanying drawings. In the following drawings / description, the same reference numbers can represent the same or corresponding hardware blocks, software blocks, or functional blocks unless otherwise described.

[0274] Figure 16 A communication system 1 based on an embodiment of the disclosure is illustrated. Figure 16 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0275] Referring to Figure 16 , a communication system (1) to which various embodiments of the disclosure are applied includes wireless devices, base stations (BSs), and networks. Herein, a wireless device denotes a device that performs communication using a radio access technology (RAT) (e.g., 5G new RAT (NR) or long term evolution (LTE)) and can be referred to as a communication / radio / 5G device. The wireless device can include, without being limited to, a robot (100a), a vehicle (100b-1, 100b-2), an extended reality (XR) device (100c), a hand-held device (100d), a home appliance (100e), an Internet of Things (IoT) device (100f), and an artificial intelligence (AI) device / server (400). For example, the vehicle can include a vehicle with a wireless communication function, an autonomous vehicle, and a vehicle capable of performing inter-vehicle communication. Herein, the vehicle can include an unmanned aerial vehicle (UAV) (e.g., a drone). The XR device can include an augmented reality (AR) / virtual reality (VR) / mixed reality (MR) device and can be implemented in the form of a head-mounted device (HMD), a head-up display (HUD) mounted in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance device, a digital signage, a vehicle, a robot, etc. The hand-held device can include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or smartglasses), and a computer (e.g., a notebook). The home appliance can include a TV, a refrigerator, and a washing machine. The IoT device can include a sensor and a smartmeter. For example, the BS and the network can be implemented as a wireless device, and a specific wireless device (200a) can operate as a BS / network node with respect to other wireless devices.

[0276] Here, in addition to LTE, NR, and 6G, a wireless communication technology implemented in the wireless devices 100a to 100f of the disclosure can also include a narrowband Internet of Things for low-power communication. In this case, for example, an NB-IoT technology can be an example of a low-power wide-area network (LPWAN) technology, and can be implemented as a standard such as LTE Cat NB1 and / or LTE Cat NB2, without being limited to the above names. Additionally or alternatively, a wireless communication technology implemented in the wireless devices 100a to 100f of the disclosure can perform communication based on an LTE-M technology. In this case, as an example, the LTE-M technology can be an example of a LPWAN, and can be referred to by various names including enhanced machine type communication (eMTC) or the like. For example, the LTE-M technology can be implemented as at least any one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-bandwidth limited (non-BL), 5) LTE-MTC, 6) LTE machine type communication, and / or 7) LTE M, without being limited to the above names. Additionally or alternatively, a wireless communication technology implemented in the wireless devices 100a to 100f of the disclosure can include at least one of Bluetooth, a low-power wide-area network (LPWAN), and ZigBee considering low-power communication, without being limited to the above names. As an example, a ZigBee technology can generate a personal area network (PAN) related to small / low-power digital communication based on various standards including IEEE 802.15.4 or the like, and can be referred to by various names.

[0277] The wireless devices 100a to 100f can be connected to the network 300 via the BS 200. An AI technology can be applied to the wireless devices 100a to 100f, and the wireless devices 100a to 100f can be connected to the AI server 400 via the network 300. The network 300 can be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. Although the wireless devices 100a to 100f can communicate with each other through the BS 200 / network 300, the wireless devices 100a to 100f can perform direct communication (e.g., sidelink communication) between each other without passing through the BS / network. For example, the vehicles 100b-1 and 100b-2 can perform direct communication (e.g., vehicle-to-vehicle (V2V) / vehicle-to-everything (V2X) communication). IoT devices (e.g., sensors) can perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

[0278] The wireless communication / connection 150a, 150b, or 150c can be established between the wireless devices 100a to 100f / BS 200 or the BS 200 / BS 200. Here, the wireless communication / connection can be established through various RATs (e.g., 5G NR) such as uplink / downlink communication 150a, sidelink communication 150b (or D2D communication), or inter-BS communication (e.g., relay, integrated access and backhaul (IAB)). The wireless devices and the BS / wireless devices can transmit / receive radio signals to / from each other through the wireless communication / connection 150a and 150b. For example, the wireless communication / connection 150a and 150b can transmit / receive signals through various physical channels. To this end, at least a part of various configuration information configuration procedures for transmitting / receiving radio signals, various signal processing procedures (e.g., channel coding / decoding, modulation / demodulation, and resource mapping / demapping), and resource allocation procedures can be performed based on various proposals of the disclosure.

[0279] Figure 17 A wireless device based on embodiments of the disclosure is illustrated. Figure 17 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0280] Referring to Figure 17 , the first wireless device (100) and the second wireless device (200) can transmit radio signals through various RATs (e.g., LTE and NR). Herein, {the first wireless device (100) and the second wireless device (200)} can correspond to {the wireless device (100x) and the BS (200)} and / or {the wireless device (100x) and the wireless device (100x)} in Figure 16 .

[0281] The first wireless device 100 can include one or more processors 102 and one or more memories 104, and can additionally include one or more transceivers 106 and / or one or more antennas 108. The processor(s) 102 can control the memory(ies) 104 and / or the transceiver(s) 106, and can be configured to implement the descriptions, functions, procedures, proposals, methods and / or operational flows disclosed in the present document. For example, the processor(s) 102 can process information in the memory(ies) 104 to generate first information / signals, and then transmit radio signals including the first information / signals through the transceiver(s) 106. The processor(s) 102 can receive radio signals including second information / signals through the transceiver(s) 106, and then store information obtained by processing the second information / signals in the memory(ies) 104. The memory(ies) 104 can be connected to the processor(s) 102, and can store various information related to operations of the processor(s) 102. For example, the memory(ies) 104 can store software code including commands for executing a part or the whole of processes controlled by the processor(s) 102 or for executing the descriptions, functions, procedures, proposals, methods and / or operational flows disclosed in the present document. Here, the processor(s) 102 and the memory(ies) 104 can be a part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver(s) 106 can be connected to the processor(s) 102, and transmit and / or receive radio signals through the antenna(s) 108. Each transceiver 106 can include a transmitter and / or a receiver. The transceiver(s) 106 can be used interchangeably with Radio Frequency (RF) units. In the present disclosure, a wireless device can represent a communication modem / circuit / chip.

[0282] The second wireless device 200 can include one or more processors 202 and one or more memories 204, and can additionally include one or more transceivers 206 and / or one or more antennas 208. The processor(s) 202 can control the memory(ies) 204 and / or the transceiver(s) 206, and can be configured to implement the descriptions, functions, procedures, proposals, methods and / or operational flows disclosed in the present document. For example, the processor(s) 202 can process information in the memory(ies) 204 to generate third information / signals, and then transmit radio signals including the third information / signals through the transceiver(s) 206. The processor(s) 202 can receive radio signals including fourth information / signals through the transceiver(s) 106, and then store information obtained by processing the fourth information / signals in the memory(ies) 204. The memory(ies) 204 can be connected to the processor(s) 202, and can store various information related to the operation of the processor(s) 202. For example, the memory(ies) 204 can store software code including commands for executing a part or the whole of processes controlled by the processor(s) 202 or for executing the descriptions, functions, procedures, proposals, methods and / or operational flows disclosed in the present document. Here, the processor(s) 202 and the memory(ies) 204 can be a part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver(s) 206 can be connected to the processor(s) 202, and transmit and / or receive radio signals through the antenna(s) 208. Each transceiver 206 can include a transmitter and / or a receiver. The transceiver(s) 206 can be used interchangeably with RF unit(s). In the present disclosure, a wireless device can represent a communication modem / circuit / chip.

[0283] Hereinafter, the hardware elements of the wireless devices 100 and 200 will be described in more detail. One or more protocol layers can be implemented by, but are not limited to, one or more processors 102 and 202. For example, one or more processors 102 and 202 can implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, and SDAP). One or more processors 102 and 202 can generate one or more protocol data units (PDUs) and / or one or more service data units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operation flows disclosed in this document. One or more processors 102 and 202 can generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flows disclosed in this document. One or more processors 102 and 202 can generate signals (e.g., baseband signals) including the PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flows disclosed in this document, and provide the generated signals to one or more transceivers 106 and 206. One or more processors 102 and 202 can receive signals (e.g., baseband signals) from one or more transceivers 106 and 206, and obtain the PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flows disclosed in this document.

[0284] One or more processors 102 and 202 can be referred to as controllers, microcontrollers, microprocessors, or microcomputers. One or more processors 102 and 202 can be implemented by hardware, firmware, software, or a combination thereof. For example, one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs) can be included in one or more processors 102 and 202. The descriptions, functions, procedures, proposals, methods, and / or operation flows disclosed in this document can be implemented using firmware or software, and the firmware or software can be configured to include modules, procedures, or functions. Firmware or software configured to perform the descriptions, functions, procedures, proposals, methods, and / or operation flows disclosed in this document can be included in one or more processors 102 and 202 or stored in one or more memories 104 and 204 so as to be driven by one or more processors 102 and 202. The descriptions, functions, procedures, proposals, methods, and / or operation flows disclosed in this document can be implemented using software or firmware in the form of code, commands, and / or command sets.

[0285] The one or more memories 104 and 204 can be connected to the one or more processors 102 and 202 and can store various types of data, signals, messages, information, programs, codes, instructions and / or commands. The one or more memories 104 and 204 can be comprised of read-only memory (ROM), random-access memory (RAM), electrically programmable read-only memory (EPROM), flash memory, a hard drive, registers, a cash memory, a computer-readable storage medium and / or combinations thereof. The one or more memories 104 and 204 can be located internal and / or external to the one or more processors 102 and 202. The one or more memories 104 and 204 can be connected to the one or more processors 102 and 202 by various technologies such as wired or wireless connections.

[0286] The one or more transceivers 106 and 206 can transmit user data, control information, and / or radio signals / channels mentioned in the methods and / or operational flows of the present document, to one or more other devices. The one or more transceivers 106 and 206 can receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functionalities, procedures, proposals, methods, and / or operational flows disclosed in the present document, from one or more other devices. For example, the one or more transceivers 106 and 206 can be connected to the one or more processors 102 and 202, and can transmit and receive radio signals. For example, the one or more processors 102 and 202 can perform control so that the one or more transceivers 106 and 206 can transmit user data, control information, or radio signals to one or more other devices. The one or more processors 102 and 202 can perform control so that the one or more transceivers 106 and 206 can receive user data, control information, or radio signals from one or more other devices. The one or more transceivers 106 and 206 can be connected to the one or more antennas 108 and 208, and the one or more transceivers 106 and 206 can be configured to transmit and receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functionalities, procedures, proposals, methods, and / or operational flows disclosed in the present document, through the one or more antennas 108 and 208. In the present document, the one or more antennas can be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). The one or more transceivers 106 and 206 can convert received radio signals / channels, etc. from RF band signals to baseband signals, in order to process received user data, control information, radio signals / channels, etc. using the one or more processors 102 and 202. The one or more transceivers 106 and 206 can convert user data, control information, radio signals / channels, etc. processed using the one or more processors 102 and 202, from baseband signals to RF band signals. To do so, the one or more transceivers 106 and 206 can include (analog) oscillators and / or filters.

[0287] Figure 18 A signal processing circuit of a transmission signal based on an embodiment of the disclosure is illustrated. Figure 18 Embodiments of the disclosure can be combined with various embodiments of the disclosure.

[0288] Referring to Figure 18 , the signal processing circuit (1000) can include a scrambler (1010), a modulator (1020), a layer mapper (1030), a precoder (1040), a resource mapper (1050), and a signal generator (1060). The operations / functions of Figure 18 may be performed, without being limited to Figure 17The processors (102, 202) and / or transceivers (106, 206) can be used. Figure 17 Implemented by processors (102, 202) and / or transceivers (106, 206) Figure 18 Hardware components. For example, it can be achieved through... Figure 17 The processors (102, 202) implement boxes 1010 to 1060. Alternatively, they can be implemented using... Figure 17 The processors (102, 202) implement boxes 1010 to 1050, and can be used to... Figure 17 The transceivers (106, 206) are used to implement the frame 1060.

[0289] Can be via Figure 18 The signal processing circuit (1000) converts codewords into radio signals. In this document, a codeword is a sequence of encoded bits for an information block. An information block may include a transport block (e.g., a UL-SCH transport block, a DL-SCH transport block). Radio signals can be transmitted via various physical channels (e.g., PUSCH and PDSCH).

[0290] Specifically, the codeword can be converted into a scrambled bit sequence by scrambler 1010. The scrambling sequence used for scrambling can be generated based on an initial value, which may include the ID information of the wireless device. The scrambled bit sequence can be modulated into a modulation symbol sequence by modulator 1020. The modulation scheme may include pi / 2-binary phase shift keying (pi / 2-BPSK), m-phase shift keying (m-PSK), and m-quadrature amplitude modulation (m-QAM). The complex modulation symbol sequence can be mapped to one or more transmission layers by layer mapper 1030. The modulation symbols of each transmission layer can be mapped (pre-coded) to one or more corresponding antenna ports by pre-encoder 1040. The output z of pre-encoder 1040 can be obtained by multiplying the output y of layer mapper 1030 by an N*M precoding matrix W. Here, N is the number of antenna ports, and M is the number of transmission layers. Pre-encoder 1040 can perform precoding after performing transform precoding (e.g., DFT) for the complex modulation symbols. Alternatively, the precoder 1040 can perform precoding without performing transform precoding.

[0291] Resource mapper 1050 maps modulation symbols for each antenna port to time-frequency resources. Time-frequency resources may include multiple symbols in the time domain (e.g., CP-OFDMA symbols and DFT-s-OFDMA symbols) and multiple subcarriers in the frequency domain. Signal generator 1060 can generate radio signals from the mapped modulation symbols, and the generated radio signals can be transmitted to other devices via each antenna. For this purpose, signal generator 1060 may include an inverse fast Fourier transform (IFFT) module, a cyclic prefix (CP) inserter, a digital-to-analog converter (DAC), and an up-converter.

[0292] Able to be with Figure 18 The signal processing procedures (1010-1060) are configured in the reverse manner for the signal processing procedures used to receive signals in a wireless device. For example, a wireless device (e.g., Figure 17 The receiver (e.g., 100, 200) can receive radio signals from the outside via the antenna port / transceiver. The received radio signals can be converted into baseband signals using a signal recovery unit. For this purpose, the signal recovery unit may include a frequency downlink converter, an analog-to-digital converter (ADC), a CP remover, and a Fast Fourier Transform (FFT) module. Next, the baseband signals can be recovered into codewords through a resource demapping process, a post-encoding process, a demodulation processor, and a descrambling process. The codewords can be recovered into the original information blocks through decoding. Therefore, the signal processing circuitry (not illustrated) used for receiving signals may include a signal recovery unit, a resource demapping unit, a post-encoder, a demodulator, a descrambler, and a decoder.

[0293] Figure 19 Another example of a wireless device based on embodiments of this disclosure is shown. (Refer to use case / service) Figure 16 Wireless devices can be implemented in various forms. Figure 19 The embodiments can be combined with various embodiments of this disclosure.

[0294] Reference Figure 19 Wireless devices (100, 200) can correspond to Figure 17 The wireless devices (100, 200) can be configured using various elements, components, units / parts and / or modules. For example, each of the wireless devices (100, 200) may include a communication unit (110), a control unit (120), a memory unit (130), and additional components (140). The communication unit may include a communication circuit (112) and one or more transceivers (114). For example, the communication circuit (112) may include... Figure 17 One or more processors (102, 202) and / or one or more memories (104, 204). For example, transceiver (114) may include one or more transceivers. Figure 17one or more transceivers (106, 206) and / or one or more antennas (108, 208). The control unit (120) is electrically connected to the communication unit (110), the memory (130), and the additional components (140), and controls the overall operation of the wireless device. For example, the control unit (120) can control the electrical / mechanical operation of the wireless device based on programs / codes / commands / information stored in the memory unit (130). The control unit (120) can transmit information stored in the memory unit (130) to the outside (e.g., other communication devices) via the communication unit (110) through a wireless / wired interface, or store in the memory unit (130) information received from the outside (e.g., other communication devices) via the communication unit (110) through a wireless / wired interface.

[0295] The additional components (140) can be variously configured according to the type of the wireless device. For example, the additional components (140) can include at least one of a power unit / battery, an input / output (I / O) unit, a driving unit, and a computing unit. The wireless device can be implemented in the form of, without limitation, a robot (100a), a vehicle (100b-1 and 100b-2), an XR device (100c), a hand-held device (100d), a home appliance (100e), an IoT device (100f), a digital broadcast terminal, a hologram device, a public safety device, an MTC device, a medical device, a financial technology device (or a financial device), a security device, a climate / environment device, an AI server / device (400), a BS (200), a network node, etc. According to a use case / service, the wireless device can be used in a mobile or fixed place. Figure 16 Figure 16 Figure 16 Figure 16 Figure 16 Figure 16 Figure 16 Figure 16

[0296] In Figure 19 ​​​​​​​​In the wireless device (100, 200), various elements, components, units / portions, and / or modules can be connected to one another through a wired interface, or at least some of them can be connected to one another through the communication unit (110) wirelessly. For example, in each of the wireless device (100, 200), the control unit (120) and the communication unit (110) can be connected through a wired connection, and the control unit (120) and the first unit (e.g., 130, 140) can be connected wirelessly through the communication unit (110). Each element, component, unit / portion, and / or module within the wireless device (100, 200) can further include one or more elements. For example, the control unit (120) can be configured by a set of one or more processors. As an example, the control unit (120) can be configured by a set of communication control processor, application processor, electronic control unit (ECU), graphic processing unit, and memory control processor. As another example, the memory (130) can be configured by a set of random access memory (RAM), dynamic RAM (DRAM), read only memory (ROM), flash memory, volatile memory, non-volatile memory, and / or a combination thereof.

[0297] Hereinafter, examples of implementing the above-described embodiments of the disclosure will be described in detail with reference to the accompanying drawings. Figure 19

[0298] Figure 20 A handheld device based on an embodiment of the disclosure is illustrated. The handheld device can include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or smartglasses), or a portable computer (e.g., a notebook computer). The handheld device can be referred to as a mobile station (MS), a user terminal (UT), a mobile subscriber station (MSS), a subscriber station (SS), an advanced mobile station (AMS), or a wireless terminal (WT). Figure 20 The embodiments of the above-described apparatuses can be combined with the various embodiments of the disclosure.

[0299] Referring to Figure 20 , the handheld device (100) can include an antenna unit (108), a communication unit (110), a control unit (120), a memory unit (130), a power supply unit (140a), an interface unit (140b), and an I / O unit (140c). The antenna unit (108) can be configured as a part of the communication unit (110). Blocks 110 to 130 / 140a to 140c correspond to blocks 110 to 130 / 140 of the above-described apparatuses, respectively. Figure 19

[0300] ​​The communication unit 110 can transmit and receive signals (e.g., data signals and control signals) to and from other wireless devices or a BS. The control unit 120 can perform various operations by controlling constituent elements of the handheld device 100. The control unit 120 can include an application processor (AP). The memory unit 130 can store data / parameters / programs / codes / commands required to drive the handheld device 100. The memory unit 130 can store input / output data / information. The power supply unit 140a can supply power to the handheld device 100 and include a wired / wireless charging circuit, a battery, etc. The interface unit 140b can support connection of the handheld device 100 to other external devices. The interface unit 140b can include various ports (e.g., audio I / O ports and video I / O ports) for connection with external devices. The I / O unit 140c can input or output video information / signals, audio information / signals, data, and / or information input by a user. The I / O unit 140c can include a camera, a microphone, a user input unit, a display unit 140d, a speaker, and / or a haptic module.

[0301] For example, in the case of data communication, the I / O unit 140c can obtain information / signals (e.g., touch, text, voice, image, or video) input by a user, and the obtained information / signals can be stored in the memory unit 130. The communication unit 110 can convert the information / signals stored in the memory into radio signals and transmit the converted radio signals directly to other wireless devices or to a BS. The communication unit 110 can receive radio signals from other wireless devices or a BS, and then restore the received radio signals to original information / signals. The restored information / signals can be stored in the memory unit 130 and can be output as various types (e.g., text, voice, image, video, or haptic) through the I / O unit 140.

[0302] Figure 21 A vehicle or an autonomous vehicle based on embodiments of the disclosure is illustrated. The vehicle or the autonomous vehicle can be implemented by a mobile robot, a car, a train, a manned / unmanned aerial vehicle (AV), a ship, etc. Figure 21 may be combined with various embodiments of the disclosure.

[0303] Referring to Figure 21 The vehicle or the autonomous vehicle (100) can include an antenna unit (108), a communication unit (110), a control unit (120), a driving unit (140a), a power supply unit (140b), a sensor unit (140c), and an autonomous driving unit (140d). The antenna unit (108) can be configured as a part of the communication unit (110). The blocks 110 / 130 / 140a to 140d correspond to the blocks 110 / 130 / 140a to 140d of FIG. 1, respectively. Figure 19the frame 110 / 130 / 140.

[0304] The communication unit 110 can transmit and receive signals (e.g., data signals and control signals) to and from external devices such as other vehicles, BSs (e.g., gNBs and road side units), and servers. The control unit 120 can perform various operations by controlling elements of the vehicle or the autonomous driving vehicle 100. The control unit 120 can include an electronic control unit (ECU). The driving unit 140a can cause the vehicle or the autonomous driving vehicle 100 to travel on a road. The driving unit 140a can include an engine, a motor, a transmission system, a wheel, a brake, a steering device, etc. The power supply unit 140b can supply power to the vehicle or the autonomous driving vehicle 100, and can include a wired / wireless charging circuit, a battery, etc. The sensor unit 140c can obtain vehicle states, external environment information, user information, etc. The sensor unit 140c can include an inertial measurement unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, a slope sensor, a weight sensor, a heading sensor, a position module, a vehicle forward / backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illumination sensor, a pedal position sensor, etc. The autonomous driving unit 140d can implement a technology for maintaining a lane in which the vehicle travels, a technology for automatically adjusting a speed (e.g., adaptive cruise control), a technology for autonomously driving along a determined path, a technology for driving by automatically setting a path in the case where a destination is set, etc.

[0305] For example, the communication unit 110 can receive map data, traffic information data, etc. from an external server. The autonomous driving unit 140d can generate an autonomous driving path and a driving plan from the obtained data. The control unit 120 can control the driving unit 140a so that the vehicle or the autonomous driving vehicle 100 can move along the autonomous driving path according to the driving plan (e.g., speed / direction control). In the middle of autonomous driving, the communication unit 110 can obtain recent traffic information data from an external server aperiodically / periodically, and surrounding traffic information data from a neighboring vehicle. In the middle of autonomous driving, the sensor unit 140c can obtain vehicle states and / or surrounding environment information. The autonomous driving unit 140d can update the autonomous driving path and the driving plan based on the newly obtained data / information. The communication unit 110 can deliver information about a vehicle position, an autonomous driving path, and / or a driving plan to an external server. The external server can predict traffic information data using an AI technology, etc. based on information collected from vehicles or autonomous driving vehicles, and provide the predicted traffic information data to the vehicles or the autonomous driving vehicles.

[0306] The claims in the specification can be combined in various ways. For example, the technical features in the method claims of the specification can be combined to be implemented or executed in an apparatus, and the technical features in the apparatus claims can be combined to be implemented or executed in a method. In addition, the technical features in the method claim(s) and the technical features in the apparatus claim(s) can be combined to be implemented or executed in an apparatus. In addition, the technical features in the method claim(s) and the technical features in the apparatus claim(s) can be combined to be implemented or executed in a method.

Claims

1. A method for performing wireless communication by a first device, the method comprising: receiving, from a second device, first sidelink control information (SCI) for scheduling a physical sidelink shared channel (PSSCH) over a physical sidelink control channel (PSCCH); receiving, from the second device, second SCI and data over the PSSCH; determining a physical sidelink feedback channel (PSFCH) resource related to the PSSCH; and starting a sidelink discontinuous reception (SL DRX) timer based on (i) hybrid automatic repeat request (HARQ) feedback based on acknowledgement-negative acknowledgement (AN) being enabled, and (ii) SL HARQ feedback not being transmitted on the PSFCH resource due to uplink (UL)-sidelink (SL) prioritization. The SL HARQ feedback comprises an acknowledgement or a negative acknowledgement.

2. The method of claim 1, wherein, The SL DRX timer comprises at least one of a SL DRX HARQ round trip time (RTT) timer or a SL DRX retransmission timer.

3. The method of claim 1, wherein, The HARQ feedback based on AN is enabled for groupcast of the first device.

4. The method of claim 1, wherein, A number of reserved resources after the SL DRX timer expires is configured differently based on at least one of a traffic type, a priority, or congestion in a resource pool.

5. The method of claim 1, wherein, 6. A first device configured to perform wireless communication, the 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 based on which, when executed, the at least one processor performs operations comprising: receiving, from a second device, first sidelink control information (SCI) for scheduling a physical sidelink shared channel (PSSCH) over a physical sidelink control channel (PSCCH); receiving, from the second device, second SCI and data over the PSSCH; determining a physical sidelink feedback channel (PSFCH) resource related to the PSSCH; and starting a sidelink discontinuous reception (SL DRX) timer based on (i) hybrid automatic repeat request (HARQ) feedback based on acknowledgement-negative acknowledgement (AN) being enabled, and (ii) SL HARQ feedback not being transmitted on the PSFCH resource due to uplink (UL)-sidelink (SL) prioritization. The SL DRX timer comprises at least one of a SL DRX HARQ round trip time (RTT) timer or a SL DRX retransmission timer.

7. The first device of claim 6, wherein, The HARQ feedback based on AN is enabled for groupcast of the first device.

8. The first device of claim 6, wherein, 9. A processing device configured to control a first device to perform wireless communication, the processing device comprising: at least one processor; and at least one memory connected to the at least one processor and storing instructions based on which, when executed, the at least one processor performs operations comprising: receiving, from a second device, first sidelink control information (SCI) for scheduling a physical sidelink shared channel (PSSCH) over a physical sidelink control channel (PSCCH); ​ receive, from the second device, a second SCI and data over the PSSCH; determine a physical sidelink feedback channel, PSFCH, resource related to the PSSCH; and start a SL discontinuous reception, DRX, timer based on (i) hybrid automatic repeat request, HARQ, feedback based on acknowledgement-negative acknowledgement being enabled, and (ii) SL HARQ feedback not being transmitted on the PSFCH resource due to uplink-sidelink, UL-sidelink, prioritization.

10. The processing device of claim 9, wherein, The SL DRX timer includes at least one of a SL DRX HARQ round trip time, RTT, timer or a SL DRX retransmission timer.

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