The present disclosure relates to a communication method and a system for converging a 5th-generation (5G) communication system for supporting higher data rates beyond a 4th-generation (4G) system with a technology for Internet of Things (IoT) is provided. The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. A decoding method for a terminal is provided. The method includes receiving a downlink control channel, receiving a reference signal in respective physical resource block (PRB) pairs, performing a correlation operation between a first sequence for the received reference signal and a second sequence for a predetermined reference signal for decoding the downlink control channel, and performing decoding of a search space for the downlink control channel in the PRB pair determined based on a result of the correlation operation.