Method and apparatus for controlling uplink power in RACH-less handover

A user equipment (UE) for controlling uplink power in a random access channel (RACH)-less handover, the UE comprising:

• a memory;
• a transceiver;
• and a processor coupling the memory and the transceiver, wherein the processor is configured to:
• control the transceiver to receive, from a source base station, a radio resource control (RRC) reconfiguration message including an uplink grant and power setting information on first transmission power and power ramping,
• wherein the uplink grant and the power setting information are determined by a target base station;
• control the transceiver to transmit, to the target base station, an RRC reconfiguration complete message with the first transmission power based on the uplink grant and the power setting information;
• control the transceiver to receive NACK from the target base station in response to the RRC reconfiguration complete message;
• ramp the first transmission power to second transmission power based on the power setting information which is determined by the target base station;
• and
• control the transceiver to transmit the RRC reconfiguration complete message with the ramped second transmission power.