Method and apparatus for delivering time-critical message between devices belonging to different cells in wireless communication system

A user equipment (UE) in a wireless communication system, the UE comprising:

• a memory;
• a transceiver;
• and
• a processor, operatively coupled to the memory and the transceiver, that:
• controls the transceiver to receive a grant of resources in a resource pool for the time-critical message from a network, and
• controls the transceiver to transmit the time-critical message by using the granted resources to another UE,
• wherein the resource pool is a common resource pool which is shared by cells in the network,
• wherein an overlapped resource by different cells has higher priority over non-overlapped resources for the transmission of the time-critical message,
• wherein the network corresponds to an eNodeB (eNB) or a road side unit (RSU) for a vehicle-to-everything (V2X) communication,
• wherein the time-critical message is overheard by the eNB or the RSU in a listening resource pool in different cells and frequencies,
• wherein the time-critical message is forwarded by the eNB or the RSU to other UEs via multicast or broadcast, and
• wherein, when the UE uses the listening resource pool configured by the eNB or the RSU, the UE reduces a required number of repetitions for the transmission of the time-critical message.