Antenna adaptation method and device in wireless communication system

1. A method of a terminal in a wireless communication system, the method comprising:

identifying operating in a second antenna mode;

determining whether a synchronization signal/physical broadcast channel block (SSB) to be measured exists in an activated bandwidth part; and

in case that the SSB to be measured does not exist in the activated bandwidth part, measuring the SSB in a first measurement gap configured by a base station,

wherein the second antenna mode is a mode operating with a configured maximum number of multi-input multi-output (MIMO) layers smaller than a maximum number of MIMO layers notified to the base station by the terminal through capability reporting, and

wherein the first measurement gap includes a time T 1 for an antenna change, a time T 2 for radio frequency (RF) tuning, and an effective measurement time to measure the SSB.

2. The method of claim 1 , further comprising:

in case that the SSB to be measured exists in the activated bandwidth part, determining whether a change in a number of activated antennas is necessary for the SSB measurement;

measuring the SSB in a second measurement gap configured by the base station in case that the change in the number of activated antennas is necessary, and measuring the SSB in an interval other than a measurement gap in case that the change in the number of activated antennas is not necessary,

wherein the second measurement gap includes the time T 1 for the antenna change and the effective measurement time to measure the SSB.

3. The method of claim 1 , further comprising:

transmitting capability reporting information related to the maximum number of MIMO layers of the terminal to the base station; and

receiving maximum MIMO layer configuration information from the base station,

wherein the maximum MIMO layer configuration information is configured for each cell or each bandwidth part.

4. The method of claim 3 , further comprising:

in case that a number of antennas to be activated based on the maximum MIMO layer configuration information is smaller than the maximum number of MIMO layers of the terminal, determining that the second antenna mode is configured.

5. The method of claim 3 , further comprising:

receiving second antenna mode configuration information from the base station through higher layer signaling; and

identifying operating in the second antenna mode when receiving the second antenna mode configuration information.

6. The method of claim 3 , further comprising:

receiving downlink control information (DCI) related to a specific number of demodulation reference signal (DMRS) antenna ports or sounding reference signal (SRS) antenna ports from the base station; and

ignoring the DCI in case that the specific number of DMRS antenna ports or SRS antenna ports is greater than a number of antennas to be activated based on the maximum MIMO layer configuration information.

7. A method of a base station in a wireless communication system, the method comprising:

receiving capability reporting information related to a maximum number of multi-input multi-output (MIMO) layers of a terminal from the terminal; and

transmitting maximum MIMO layer configuration information to the terminal,

wherein the maximum MIMO layer configuration information is configured for each cell or each bandwidth part, and

wherein in case that a number of MIMO layers based on the maximum MIMO layer configuration information is smaller than the maximum number of MIMO layers based on the capability reporting information, a second antenna mode is configured to the terminal.

8. The method of claim 7 , further comprising:

transmitting downlink control information (DCI) related to a specific number of demodulation reference signal (DMRS) antenna ports or sounding reference signal (SRS) antenna ports to the terminal,

wherein the specific number of DMRS antenna ports or SRS antenna ports is not greater than a number of antennas to be activated based on the maximum MIMO layer configuration information.

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

a transceiver; and

a controller configured to identify operating in a second antenna mode, to determine whether a synchronization signal/physical broadcast channel block (SSB) to be measured exists in an activated bandwidth part, and in case that the SSB to be measured does not exist in the activated bandwidth part, to measure the SSB in a first measurement gap configured by a base station,

wherein the second antenna mode is a mode operating with a configured maximum number of multi-input multi-output (MIMO) layers smaller than a maximum number of MIMO layers notified to the base station by the terminal through capability reporting, and

wherein the first measurement gap includes a time T 1 for an antenna change, a time T 2 for radio frequency (RF) tuning, and an effective measurement time to measure the SSB.

10. The terminal of claim 9 , wherein the controller is further configured to, in case that the SSB to be measured exists in the activated bandwidth part, determine whether a change in a number of activated antennas is necessary for the SSB measurement, to measure the SSB in a second measurement gap configured by the base station in case that the change in the number of activated antennas is necessary, and to measure the SSB in an interval other than a measurement gap in case that the change in the number of activated antennas is not necessary,

wherein the second measurement gap includes the time T 1 for the antenna change and the effective measurement time to measure the SSB.

11. The terminal of claim 9 , wherein the controller is further configured to transmit capability reporting information related to the maximum number of MIMO layers of the terminal to the base station, and to receive maximum MIMO layer configuration information from the base station,

wherein the maximum MIMO layer configuration information is configured for each cell or each bandwidth part.

12. The terminal of claim 11 , wherein the controller is further configured to, in case that a number of antennas to be activated based on the maximum MIMO layer configuration information is smaller than the maximum number of MIMO layers of the terminal, determine that the second antenna mode is configured.

13. The terminal of claim 11 , wherein the controller is further configured to receive downlink control information (DCI) related to a specific number of demodulation reference signal (DMRS) antenna ports or sounding reference signal (SRS) antenna ports from the base station, and to ignore the DCI in case that the specific number of DMRS antenna ports or SRS antenna ports is greater than a number of antennas to be activated based on the maximum MIMO layer configuration information.

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

a transceiver; and

a controller configured to receive capability reporting information related to a maximum number of multi-input multi-output (MIMO) layers of a terminal from the terminal, and to transmit maximum MIMO layer configuration information to the terminal,

wherein the maximum MIMO layer configuration information is configured for each cell or each bandwidth part, and in case that a number of MIMO layers based on the maximum MIMO layer configuration information is smaller than the maximum number of MIMO layers based on the capability reporting information, a second antenna mode is configured to the terminal.

15. The base station of claim 14 , wherein the controller is further configured to transmit downlink control information (DCI) related to a specific number of demodulation reference signal (DMRS) antenna ports or sounding reference signal (SRS) antenna ports to the terminal,

wherein the specific number of DMRS antenna ports or SRS antenna ports is not greater than a number of antennas to be activated based on the maximum MIMO layer configuration information.