System and method of handling bandwidth part inactivity timer

A method of a base station, the method comprising:

• transmitting, to a user equipment (UE), first information of a first timer of a bandwidth part inactivity associated with a bandwidth part of a primary cell (PCell) and second information of a second timer of a bandwidth part inactivity associated with a bandwidth part of a secondary cell (SCell);
• receiving, from the UE, a first message associated with a random access procedure on the PCell or the SCell;
• and
• transmitting, to the UE, a second message associated with the random access procedure on the PCell,
• wherein the first timer, if running, is stopped in response to identifying that the random access procedure is initiated on the PCell, and
• wherein the first timer and the second timer, if running, are stopped in response to identifying that the random access procedure is initiated on the SCell.

A user equipment (UE) in a wireless communication system, the UE comprising:

• a transceiver;
• and
• at least one processor coupled to the transceiver, the at least one processor configured to:
• control the transceiver to receive, from a base station, first information of a first timer of a bandwidth part inactivity associated with a bandwidth part of a primary cell (PCell) and second information of a second timer of a bandwidth part inactivity associated with a bandwidth part of a secondary cell (SCell),
• identify that a random access procedure is initiated on the PCell or the Scell,
• stop the first timer, if running, in response to identifying that the random access procedure is initiated on the Pcell, and
• stop the first timer and the second timer, if running, in response to identifying that the random access procedure is initiated on the SCell.

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

• a transceiver;
• and
• at least one processor coupled to the transceiver, the at least one processor configured to control the transceiver to:
• transmit, to a user equipment (UE), first information of a first timer of a bandwidth part inactivity associated with a bandwidth part of a primary cell (PCell) and second information of a second timer of a bandwidth part inactivity associated with a bandwidth part of a secondary cell (SCell),
• receive, from the UE, a first message associated with a random access procedure on the PCell or the Scell, and
• transmit, to the UE, a second message associated with the random access procedure on the PCell,
• wherein the first timer, if running, is stopped in response to identifying that the random access procedure is initiated on the PCell, and
• wherein the first timer and the second timer, if running, are stopped in response to identifying that the random access procedure is initiated on the SCell.