Method and apparatus for transmitting and receiving downlink control information in wireless communication system

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

• a transceiver configured to transmit and receive a signal;
• and
• a controller coupled with the transceiver and configured to:
• receive, from a base station in the wireless communication system, first downlink control information (DCI) in a search space of the terminal, the first DCI scheduling a downlink data,
• identify whether the downlink data scheduled by the first DCI is mapped to at least one resource element of a control channel, and
• receive, from the base station, second DCI in a part of the search space of the terminal without the at least one resource element, in case that the downlink data is mapped to the at least one resource element of the control channel, and
• receive, from the base station, the second DCI in a whole of the search space, in case that the downlink data is not mapped to the at least one resource element of the control channel.

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

• transmitting, to a terminal in the wireless communication system, first downlink control information (DCI) in a search space of the terminal, the first DCI scheduling a downlink data;
• identifying whether the downlink data scheduled by the first DCI is mapped to at least one resource element of a control channel;
• transmitting, to the terminal, second DCI in a part of the search space of the terminal without the at least one resource element, in case that the downlink data is mapped to the at least one resource element of the control channel;
• and
• transmitting, to the terminal, the second DCI in a whole of the search space, in case that the downlink data is not mapped to the at least one resource element of the control channel.

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

• a transceiver configured to transmit and receive a signal;
• and
• a controller coupled with the transceiver and configured to:
• transmit, to a terminal in the wireless communication system, first downlink control information (DCI) in a search space of the terminal, the first DCI scheduling a downlink data,
• identify whether the downlink data scheduled by the first DCI is mapped to at least one resource element of a control channel,
• transmit, to the terminal, second DCI in a part of the search space of the terminal without the at least one resource element, in case that the downlink data is mapped to the at least one resource element of the control channel, and
• transmit, to the terminal, the second DCI in a whole of the search space, in case that the downlink data is not mapped to the at least one resource element of the control channel.