Meanwhile, in the next-generation system, if UL transmission and SL transmission of the UE collide in the same serving cell, the UE may select and perform either UL transmission or SL transmission according to a priority and may drop the remaining transmission. In addition, in the next-generation system, if UL transmission and SL transmission of the UE overlap in time in different serving cells, the UE may use transmit power less than or equal to the maximum power of the UE by lowering power of SL transmission or UL transmission according to a priority through power control. Herein, the UE may determine whether the priority of the UL transmission is high or the priority of the SL transmission is high, by comparing an L1-priority (e.g., a value indicated by a SCI) for SL transmission with a (pre-)configured threshold.
Specifically, for example, in the case of UL transmission which does not include SL HARQ report, the threshold may be configured or pre-configured differently for the UE, based on whether or not the UL transmission corresponds to URLLC (or whether or not a “priority value” included in a DCI related to the UL transmission is 1 and/or whether or not a “priority value” of the UL transmission (e.g., RRC message) is 1).