Method and apparatus for decoding downlink control signal in wireless cellular communication system

A method performed by a base station in a wireless communication system, the method comprising:

• identifying a plurality of search spaces configured for a terminal including a common search space (CSS) and a user equipment specific search space (USS);
• and
• identifying that control channel elements (CCEs) associated with the CSS and CCEs associated with the USS are same;
• transmitting, to the terminal, downlink control information (DCI) on a physical downlink control channel (PDCCH) in the same CCEs of the CSS and the USS;
• and
• receiving, from the terminal, a physical uplink share channel (PUSCH) based on the DCI,
• wherein in case that a format of the DCI is both a DCI format associated with the CSS and a DCI format associated with the USS and the CCEs associated with the CSS and the CCEs associated with the USS are same, only the DCI format associated with the CSS is decoded.

A terminal in a wireless communication system, the terminal comprising:

• a transceiver configured to transmit or receive a signal;
• and
• at least one processor configured to:
• identify a plurality of search spaces for the terminal including a common search space (CSS) and a user equipment specific search space (USS),
• identify that control channel elements (CCEs) associated with the first CSS and CCEs associated with the USS are same,
• decode only a downlink control information (DCI) format associated with the CSS, in case that the DCI format associated with the CSS and a DCI format associated with the USS are same and the CCEs associated with the CSS and the CCEs associated with the USS are same, and
• transmit, to a base station, a physical uplink shared channel (PUSCH) based on the decoded DCI format associated with the CSS.

A base station in a wireless communication system, the base station comprising:

• a transceiver configured to transmit or receive a signal;
• and
• at least one processor configured to:
• identify a plurality of search spaces configured for a terminal including a common search space (CSS) and a user equipment specific search space (USS),
• identify that control channel elements (CCEs) associated with the CSS and CCEs associated with the USS are same,
• transmit, to the terminal, downlink control information (DCI) on a physical downlink control channel (PDCCH) in the same CCEs of the CSS and the USS, and
• receive, from the terminal, a physical uplink share channel (PUSCH) based on the DCI,
• wherein in case that a format of the DCI is both a DCI format associated with the CSS and a DCI format associated with the USS and the CCEs associated with the CSS and the CCE associated with the USS are same, only the DCI format associated with the CSS is decoded.