Method and apparatus for performing uplink transmissions power control on a set of cells based on layer 2 mobility in mobile wireless communication system

1 . A method by a terminal, the method comprising:

receiving, by the terminal from a base station, a first Radio Resource Control (RRC) message, wherein the first RRC message comprises a first identifier and a second identifier;

receiving, by the terminal from the base station, a second RRC message, wherein the second RRC message comprises a third identifier and a fourth identifier;

receiving, by the terminal from the base station, a first Medium Access Control (MAC) Control Element (CE), wherein the first MAC CE comprises an identifier related to first configuration information, and wherein the first configuration information comprises the first identifier and the second identifier;

monitoring, by the terminal and based on the first identifier and the second identifier, Physical Downlink Control Channel (PDCCH);

adjusting uplink transmission power based on a Transmission Power Control (TPC) command in Downlink Control Information (DCI) with Cyclic Redundancy Check (CRC) scrambled by the second identifier;

performing uplink transmission based on uplink scheduling information in DCI with CRC scrambled by the first identifier;

receiving, by the terminal from the base station, a second MAC CE, wherein the second MAC CE comprises an identifier related to second configuration information, and wherein the second configuration information comprises the third identifier and the fourth identifier;

initiating, by the terminal based on a specific field in the second MAC CE being set to a specific value, random access procedure;

adjusting uplink transmission power based on a TPC command in DCI with CRC scrambled by the fourth identifier; and

performing uplink transmission based on uplink scheduling information in DCI with CRC scrambled by the third identifier.

2 . A terminal in a wireless communication system, the terminal comprising: a transceiver configured to transmit and receive a signal; and

a controller configured to control the transceiver to:

receive, from a base station, a first Radio Resource Control (RRC) message, wherein the first RRC message comprises a first identifier and a second identifier;

receive, from the base station, a second RRC message, wherein the second RRC message comprises a third identifier and a fourth identifier;

receive, from the base station, a first Medium Access Control (MAC) Control Element (CE), wherein the first MAC CE comprises an identifier related to first configuration information, and wherein the first configuration information comprises the first identifier and the second identifier;

monitor, based on the first identifier and the second identifier, Physical Downlink Control Channel (PDCCH);

adjust uplink transmission power based on a Transmission Power Control (TPC) command in Downlink Control Information (DCI) with Cyclic Redundancy Check (CRC) scrambled by the second identifier;

perform uplink transmission based on uplink scheduling information in DCI with CRC scrambled by the first identifier;

receive, from the base station, a second MAC CE, wherein the second MAC CE comprises an identifier related to second configuration information, and wherein the second configuration information comprises the third identifier and the fourth identifier;

initiate, based on a specific field in the second MAC CE being set to a specific value, random access procedure;

adjust uplink transmission power based on a TPC command in DCI with CRC scrambled by the fourth identifier; and

perform uplink transmission based on uplink scheduling information in DCI with CRC scrambled by the third identifier.