Abstract: A method of a first user equipment (UE) may comprise: receiving a downlink (DL) reference signal transmitted by a base station using a beam included in a beam candidate group to be used for sidelink (SL) communication with a second UE; measuring a DL reference signal received power (RSRP) of the DL reference signal; determining a transmit power of a beam included in the beam candidate group based on the measured DL RSRP; and transmitting SL data to the second UE with the determined transmit power.

Abstract: An operation method of a relay node may include: receiving, from a first communication node, first data composed of n bits; receiving, from a second communication node, second data composed of m bits; in response to determining that n is greater than m, generating first T-data of m bits excluding (n-m) bits from the n-bits of the first data and first R-data of (n-m) bits; generating third data by performing a network coding operation on the first T-data and the second data; transmitting the third data to the first communication node; and transmitting the third data and the first R-data to the second communication node.

Abstract: A method of a first terminal may include: identifying first RB set(s) to be used for SL communication among consecutive RB sets through an LBT procedure; identifying a first subchannel group included in the first RB set(s) and a second subchannel group including a first PRB in the first RB set(s), the first PRB being not included in the first subchannel group; configuring the first PRB within the second subchannel group as an SL communication resource; and transmitting, to a second terminal, control information indicating that the first PRB is configured as the SL communication resource.

Abstract: Disclosed are a relay method and device in a communication system. An operation method of a first communication node comprises the steps of: transmitting a reference signal to one or more candidate R nodes; receiving first feedback information including a minimum value of a first RSRP from a first candidate R node belonging to the one or more candidate R nodes; receiving second feedback information including a minimum value of a second RSRP from a second candidate R node belonging to the one or more candidate R nodes; comparing a first value based on the first feedback information with a second value based on the second feedback information; when the first value is greater than the second value, selecting the first candidate R node as an R node that is to perform a relaying operation; and communicating with a second communication node via the R node.

Abstract: An operation method of a terminal in a communication system may include: receiving, from a base station, primary RA configuration information for a primary RA procedure; receiving, from the base station, secondary RA configuration information for a secondary RA procedure; transmitting a primary RA preamble to the base station by using a primary RA resource indicated by the primary RA configuration information; receiving, from the base station, secondary RA indication information in response to the primary RA preamble, the secondary RA indication information indicating to perform the secondary RA procedure instead of the primary RA procedure; and transmitting a secondary RA preamble to the base station by using a secondary RA resource indicated by the secondary RA configuration information.

Abstract: A method of a transmitting terminal may include: setting an initial beam pairing flag indicating that the transmitting terminal transmitting sidelink-synchronization signal blocks (S-SSBs) is not a synchronization reference terminal; transmitting a plurality of S-SSBs including the initial beam pairing flag in a beam sweeping scheme; receiving, from a receiving terminal, information on a preferred beam among a plurality of beams through which the plurality of S-SSBs are transmitted; and transmitting data to the receiving terminal using the preferred beam.

Abstract: A method of a transmitting terminal may include: determining a beam candidate set including two or more beams usable for sidelink communication with a receiving terminal from among a plurality of beams that can be beam-formed; determining a resource set for each beam within the beam candidate set through resource sensing, such that the resource set has candidate resources equal to or greater than a predetermined number of candidate resources; selecting a beam and a resource to be used for sidelink communication with the receiving terminal based on the beam candidate set and the resource set; and transmitting sidelink data to the receiving terminal using the selected beam and the selected resource.

Abstract: An operation method of a first terminal may include: transmitting a plurality of sidelink-synchronization signal blocks (S-SSBs); performing a monitoring operation on a plurality of response resources associated with the plurality of S-SSBs; receiving a first response signal from a second terminal in a first response resource among the plurality of response resources; identifying a first S-SSB associated with the first response resource among the plurality of S-SSBs; and determining a first transmission beam through which the first S-SSB is transmitted among a plurality of transmission beams of the first terminal as an optimal transmission beam.

Abstract: A communication method of a base station may include: configuring a first band as a communication band from an entire carrier frequency band of the base station, the entire carrier frequency band including the first band and a second band; transmitting a synchronization signal in the first band by beamforming in one of both directions of a moving path of a transportation means; communicating with a terminal by beamforming in a same direction as the synchronization signal in the first band; and transmitting a synchronization signal in the second band by beamforming in the same direction as the synchronization signal in the first band.

Abstract: Disclosed are a method and an apparatus for sidelink resource allocation in a wireless communication system. The method and apparatus for sidelink resource allocation in a wireless communication system, a method of a first terminal, may include: receiving, from a base station, resource pool configuration information including information on a resource sensing type; in response to that the information on the resource sensing type indicates a sensing operation, sensing transmission resource(s) within a sensing period according to the resource sensing type based on the scheduling information; selecting a first resource based on a result of the sensing on the transmission resource(s); and performing sidelink communication using the selected first resource.

Abstract: A method for sidelink groupcast transmission, performed by a transmitting terminal, may comprise configuring a first feedback resource located at a first time point and a second feedback resource located at a later time point than the first time point; transmitting groupcast control information and groupcast data to a receiving terminal group; receiving first feedback information through the first feedback resource from at least one terminal belonging to a first subgroup of the receiving terminal group; and receiving second feedback information through the second feedback resource from at least one terminal belonging to a second subgroup of the receiving terminal group.

Abstract: An operation method of a relay node may include: receiving, from a first communication node, first data composed of n bits; receiving, from a second communication node, second data composed of m bits; in response to determining that n is greater than m, generating first T-data of m bits excluding (n?m) bits from the n-bits of the first data and first R-data of (n?m) bits; generating third data by performing a network coding operation on the first T-data and the second data; transmitting the third data to the first communication node; and transmitting the third data and the first R-data to the second communication node.

Abstract: An operation method of a terminal in a communication system may include: receiving, from a base station, primary RA configuration information for a primary RA procedure; receiving, from the base station, secondary RA configuration information for a secondary RA procedure; transmitting a primary RA preamble to the base station by using a primary RA resource indicated by the primary RA configuration information; receiving, from the base station, secondary RA indication information in response to the primary RA preamble, the secondary RA indication information indicating to perform the secondary RA procedure instead of the primary RA procedure; and transmitting a secondary RA preamble to the base station by using a secondary RA resource indicated by the secondary RA configuration information.

Abstract: An operation method of an IAB node in a communication system may comprise: measuring a power difference between a first signal received from a first node and a second signal received from a second node; controlling a transmit power of each of the first node and the second node based on the power difference; generating scheduling information for allowing the first node and the second node to simultaneously transmit signals; transmitting the scheduling information to the first node and the second node; and receiving signals that the first node and the second node simultaneously transmit according to the scheduling information by using the transmit power.

Abstract: A method for performing sidelink groupcast transmission by a transmission terminal includes the steps of: classifying reception terminals belonging to a subject group into two or more subgroups; allocating different groupcast feedback schemes to the two or more subgroups; performing groupcast transmission to the reception terminals; and receiving feedback information from terminals belonging to at least one subgroup among the two or more subgroups according to the different groupcast feedback schemes.

Abstract: A sidelink communication method performed by a UE in a communication system may comprise receiving, from a base station, a message including configuration information of a subchannel which is a sensing unit of a resource pool; determining a size of the subchannel based on the configuration information; and performing a sensing operation in units of the subchannel in the resource pool. Therefore, the sidelink communication can be efficiently performed, and the performance of the communication system can be improved.

Abstract: An operation method of a first terminal, performed in a communication system, may comprise receiving sidelink resource allocation information from a base station; receiving a first sidelink signal from a second terminal based on the sidelink resource allocation information; calculating a path loss experienced by the first sidelink signal based on the first sidelink signal; transmitting a second sidelink signal including information on the path loss experienced by the first sidelink signal to the second terminal; and receiving, from the second terminal, a third sidelink signal to which a sidelink transmit power determined based on the path loss is allocated.

Abstract: An operation method of a terminal in a communication system includes receiving a message from a base station, the message including physical random access channel (PRACH) configuration information indicating a PRACH slot; determining a start symbol to which a PRACH is mapped among symbols constituting the PRACH slot based on a type of the PRACH slot; mapping the PRACH from the start symbol in the PRACH slot; and transmitting the PRACH mapped to the PRACH slot to the base station.

Abstract: An operation method of a first terminal, performed in a communication system, may comprise receiving sidelink resource allocation information from a base station; receiving a first sidelink signal from a second terminal based on the sidelink resource allocation information; calculating a path loss experienced by the first sidelink signal based on the first sidelink signal; transmitting a second sidelink signal including information on the path loss experienced by the first sidelink signal to the second terminal; and receiving, from the second terminal, a third sidelink signal to which a sidelink transmit power determined based on the path loss is allocated.

Abstract: A method of performing, by a device, a random access procedure in a radio communication system includes: receiving from a base station RACH configuration information; and transmitting a first message based on the received RACH configuration information. Herein, a plurality of SSBs may be in association with a plurality of preambles, and the first message may be transmitted in a time domain through a plurality of RACH resources.