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EP-4131823-B1 - METHOD AND DEVICE BY WHICH RECEPTION USER EQUIPMENT CARRIES OUT POWER SAVING OPERATION ON BASIS OF PSFCH IN NR V2X

EP4131823B1EP 4131823 B1EP4131823 B1EP 4131823B1EP-4131823-B1

Inventors

  • PARK, GIWON
  • LEE, SEUNGMIN
  • BACK, SEOYOUNG
  • SEO, HANBYUL
  • HONG, Jongwoo

Dates

Publication Date
20260506
Application Date
20220324

Claims (15)

  1. A method for performing, by a first apparatus (100), wireless communication, the method comprising: obtaining a sidelink, SL, discontinuous reception, DRX, configuration including information related to an SL DRX hybrid automatic repeat request, HARQ, round trip time, RTT, timer value; receiving sidelink control information, SCI, for scheduling of a physical sidelink shared channel, PSSCH, through a physical sidelink control channel, PSCCH, from a second apparatus (200), during an active time of the SL DRX configuration; receiving a medium access control, MAC, protocol data unit, PDU, through the PSSCH from the second apparatus (200), during the active time; and starting a SL DRX HARQ RTT timer, based on a physical sidelink feedback channel, PSFCH, resource being configured to an SL grant related to the SCI and a HARQ feedback related to the MAC PDU being disabled, wherein the SL DRX HARQ RTT timer is started in a slot following an end of the transmission through the PSSCH, based on the SCI including information related to a retransmission resource of the MAC PDU, or, wherein the SL DRX HARQ RTT timer is started in a slot following an end of the PSFCH resource and runs as long as the SL DRX HARQ RTT timer value, based on the SCI not including information related to a retransmission resource of the MAC PDU.
  2. The method of claim 1, further comprising: receiving a retransmission of the MAC PDU, based on the SL HARQ RTT timer being expired and the retransmission resource.
  3. The method of claim 2, wherein the receiving the retransmission of the MAC PDU includes: starting an SL HARQ retransmission timer, based on the SL HARQ RTT timer being expired; and receiving the retransmission of the MAC PDU, based on the SL HARQ retransmission timer running and the retransmission resource.
  4. The method of claim 1, further comprising: transmitting HARQ NACK information related to the MAC PDU to the second apparatus (200), during the active time.
  5. The method of claim 1, wherein the first apparatus (100) doesn't perform a monitoring for a PSCCH of a PSSCH, based on the SL HARQ RTT timer running.
  6. The method of claim 5, wherein the PSCCH or the PSSCH, for which the monitoring is not performed based on the SL HARQ RTT timer running, is related to an SL HARQ process related to the MAC PDU.
  7. The method of claim 1, wherein the SL DRX HARQ RTT timer runs from the next slot of the end of the transmission through the PSSCH until before the retransmission resource time point, based on the SCI including the information related to the retransmission resource of the MAC PDU.
  8. The method of claim 1, further comprising: determining that the retransmission resource of the MAC PDU exists after 32 slots from the SCI, based on the SCI not including the information related to the retransmission resource of the MAC PDU.
  9. The method of claim 7, wherein the first apparatus (100) operates in a sleep mode from a time of transmission of the SCI to a time of the PSFCH resource, based on the MAC PDU being a HARQ enabled MAC PDU.
  10. The method of claim 1, wherein the SL DRX configuration is obtained through a PC5RRC message.
  11. A first apparatus (100) configured for performing wireless communication, the first apparatus (100) comprising: one or more memories (104) storing instructions; one or more transceivers (106); and one or more processors (102) connected to the one or more memories (104) and the one or more transceivers (106), wherein the one or more processors (102) are configured to execute the instructions to: obtain a sidelink, SL, discontinuous reception, DRX, configuration including information related to an SL DRX hybrid automatic repeat request, HARQ, round trip time, RTT, timer value; receive sidelink control information, SCI, for scheduling of a physical sidelink shared channel, PSSCH, through a physical sidelink control channel, PSCCH, from a second apparatus (200), during an active time of the SL DRX configuration; receive a medium access control, MAC, protocol data unit, PDU, through the PSSCH from the second apparatus (200), during the active time; and start an SL DRX HARQ RTT timer, based on a physical sidelink feedback channel, PSFCH, resource being configured to an SL grant related to the SCI and a HARQ feedback related to the MAC PDU being disabled, wherein the SL DRX HARQ RTT timer is started in a slot following an end of the transmission through the PSSCH, based on the SCI including information related to a retransmission resource of the MAC PDU, or, wherein the SL DRX HARQ RTT timer is started in a slot following an end of the PSFCH resource and runs as long as the SL DRX HARQ RTT timer value, based on the SCI not including information related to a retransmission resource of the MAC PDU.
  12. The first apparatus (100) of claim 11, further configured to receive a retransmission of the MAC PDU, based on the SL HARQ RTT timer being expired and the retransmission resource.
  13. An apparatus configured to control a first user equipment, UE, the apparatus comprising: one or more processors; and one or more memories operably connectable to the one or more processors and storing instructions, wherein the one or more processors are configured to execute the instructions to: obtain a sidelink, SL, discontinuous reception, DRX, configuration including information related to an SL DRX hybrid automatic repeat request, HARQ, round trip time, RTT, timer value; receive sidelink control information, SCI, for scheduling of a physical sidelink shared channel, PSSCH, through a physical sidelink control channel, PSCCH, from a second UE, during an active time of the SL DRX configuration; receive a medium access control, MAC, protocol data unit, PDU, through the PSSCH from the second UE, during the active time; and start an SL DRX HARQ RTT timer, based on a physical sidelink feedback channel, PSFCH, resource being configured to an SL grant related to the SCI and a HARQ feedback related to the MAC PDU being disabled, wherein the SL DRX HARQ RTT timer is started in a slot following an end of the transmission through the PSSCH, based on the SCI including information related to a retransmission resource of the MAC PDU, or, wherein the SL DRX HARQ RTT timer is started in a slot following an end of the PSFCH resource and runs as long as the SL DRX HARQ RTT timer value, based on the SCI not including information related to a retransmission resource of the MAC PDU.
  14. The apparatus of claim 13, further comprising: receiving a retransmission of the MAC PDU, based on the SL HARQ RTT timer being expired and the retransmission resource.
  15. The apparatus of claim 14, wherein the receiving the retransmission of the MAC PDU includes: starting an SL HARQ retransmission timer, based on the SL HARQ RTT timer being expired; and receiving the retransmission of the MAC PDU, based on the SL HARQ retransmission timer running and the retransmission resource.

Description

BACKGROUND OF THE DISCLOSURE Field of the disclosure This disclosure relates to a wireless communication system. Related Art Sidelink (SL) communication is a communication scheme in which a direct link is established between User Equipments (UEs) and the UEs exchange voice and data directly with each other without intervention of an evolved Node B (eNB). SL communication is under consideration as a solution to the overhead of an eNB caused by rapidly increasing data traffic. Vehicle-to-everything (V2X) refers to a communication technology through which a vehicle exchanges information with another vehicle, a pedestrian, an object having an infrastructure (or infra) established therein, and so on. The V2X may be divided into 4 types, such as vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), and vehicle-to-pedestrian (V2P). The V2X communication may be provided via a PC5 interface and/or Uu interface. Meanwhile, as a wider range of communication devices require larger communication capacities, the need for mobile broadband communication that is more enhanced than the existing Radio Access Technology (RAT) is rising. Accordingly, discussions are made on services and user equipment (UE) that are sensitive to reliability and latency. And, a next generation radio access technology that is based on the enhanced mobile broadband communication, massive Machine Type Communication (MTC), Ultra-Reliable and Low Latency Communication (URLLC), and so on, may be referred to as a new radio access technology (RAT) or new radio (NR). Herein, the NR may also support vehicle-to-everything (V2X) communication. The 3GPP Draft No. R2-2101727 discusses high-level principles for SL DRX. The 3GPP Draft No. R2-1912101 discusses DRX operation for non-numerical k1. SUMMARY OF THE DISCLOSURE Technical Solutions According to an aspect of the present disclosure, a method for a first apparatus to perform wireless communication is proposed as set forth in the appended claims. According to another aspect of the present disclosure, a first apparatus configured for performing wireless communication is proposed as set forth in the appended claims. According to yet another aspect of the present disclosure, an apparatus configured to control a first user equipment, UE, is proposed as set forth in the appended claims. In the following, embodiments and/or examples not falling within the scope of the appended claims should be understood as mere examples useful for understanding the invention. EFFECTS OF THE DISCLOSURE The user equipment (UE) may efficiently perform retransmission based on hybrid automatic repeat request (HARQ) feedback. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a structure of an NR system, based on an embodiment of the present disclosure.FIG. 2 shows a radio protocol architecture, based on an embodiment of the present disclosure.FIG. 3 shows a structure of a radio frame of an NR, based on an embodiment of the present disclosure.FIG. 4 shows a structure of a slot of an NR frame, based on an embodiment of the present disclosure.FIG. 5 shows an example of a BWP, based on an embodiment of the present disclosure.FIG. 6 shows a procedure of performing V2X or SL communication by a UE based on a transmission mode, based on an embodiment of the present disclosure.FIG. 7 shows three cast types, based on an embodiment of the present disclosure.FIG. 8 shows an example of a retransmission procedure according to an SL DRX operation, according to an embodiment of the present disclosure.FIG. 9 shows an example of a retransmission procedure according to an SL DRX operation, according to an embodiment of the present disclosure.FIG. 10 shows an example of a retransmission procedure according to an SL DRX operation, according to an embodiment od the present disclosureFIG. 11 shows a procedure in which a first apparatus performs wireless communication, according to an embodiment of the present disclosure.FIG. 12 shows a procedure in which a second apparatus performs wireless communication, according to an embodiment of the present disclosure.FIG. 13 shows a communication system 1, based on an embodiment of the present disclosure.FIG. 14 shows wireless devices, based on an embodiment of the present disclosure.FIG. 15 shows a signal process circuit for a transmission signal, based on an embodiment of the present disclosure.FIG. 16 shows another example of a wireless device, based on an embodiment of the present disclosure.FIG. 17 shows a hand-held device, based on an embodiment of the present disclosure.FIG. 18 shows a vehicle or an autonomous vehicle, based on an embodiment of the present disclosure. DESCRIPTION OF EXEMPLARY EMBODIMENTS In the present disclosure, "A or B" may mean "only A", "only B" or "both A and B." In other words, in the present disclosure, "A or B" may be interpreted as "A and/or B". For example, in the present disclosure, "A, B, or C" may mean "only A", "only B", "only C", or "any combination o