METHOD AND APPARATUS FOR PERFORMING AN UPLINK TIMING SYNCHRONIZATION PROCEDURE UPON HANDOVER IN A MOBILE COMMUNICATION SYSTEM USING AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING

摘要

An uplink timing synchronization procedure performance method during handover in an OFDM(Orthogonal Frequency Division Multiplexing)-type mobile communication system and a device are provided to enable a UE(User Equipment) not to perform an unnecessary uplink timing synchronization procedure during handover, thereby preventing a signaling overhead of uplink/downlink. A message including information on neighboring cells is transmitted to an E-NB(Evolved Node B)(402)(411). A response message including information for performing handover for the transmitted message is received from the E-NB(413). It is checked whether information on performance of an uplink timing synchronization procedure with the second cell is included in the received message(421). If so, after handover to the second cell is performed, an uplink signal or data is immediately transmitted without performing the uplink timing synchronization procedure to the second cell(423).