Lastly, the URLLC service is a mission-critical cellular-based wireless communication service. For example, services used for remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote healthcare, and emergency alert may be considered for URLLC. Therefore, communication provided by URLLC should provide ultra-low latency and ultra-high reliability. For example, the service supporting URLLC should satisfy an air interface latency less than 0.5 millisecond (ms) and, at the same time, has a requirement of a packet error rate equal to or less than 10^?5. Therefore, for the service supporting URLLC, the 5G system should provide a smaller transmit time interval (TTI) compared to other services and, at the same time, requires a design in which wide resources should be allocated in a frequency band in order to ensure the reliability of a communication link.

The three services of 5G, that is, eMBB, URLLC, and mMTC, may be multiplexed and transmitted in one system. In this example, in order to satisfy different requirements that the respective services have, it is possible to use different transmission/reception techniques and transmission/reception parameters for the respective services.

In 5G, either a wideband DMRS (WB-RS) or a narrowband DMRS (NB-RS) may be configured as a DMRS for decoding of a DL control channel. In this configuration, when a control resource set (CORESET) configured as an NB-RS and a CORESET configured as a WB-RS overlap entirely or partially, there may occur a problem of an assumption of DMRS configuration necessary to decode a DL control channel in an overlapping region. In order to solve this problem, embodiments of the disclosure propose methods, including an assumption of a WB-RS, a rate matching of a CORESET, skipping of monitoring of a CORESET, and the like.