APPARATUS FOR PERFORMING UPLINK SYNCHRONIZATION IN MULTIPLE COMPONENT CARRIER SYSTEM AND METHOD THEREFOR

摘要

PURPOSE: An apparatus for performing uplink synchronization in a multiple element carrier system and a method thereof are provided to prevent interference of uplink due to the inconsistency of a time alignment value. CONSTITUTION: A terminal(1200) includes a mode controller(1211) and a transmitter(1220). The mode controller controls uplink time based on a time alignment value in a time alignment group including a sub-serving cell of the terminal and measures the change of a downlink timing value by time based on the downlink timing reference of the sub-serving cell. The mode controller determines validity of the uplink time using the change of the measured downlink timing value. The transmitter transmits a message including the result of validity determination to a base station on a main serving cell. [Reference numerals] (1205) Terminal receiver; (1210) Terminal processor; (1211) Mode controller; (1212,1272) Random access processor; (1220) Terminal transmitter; (1255) Base station transmitter; (1260) Base station receiver; (1270) Base station processor; (1271) Update determination unit; (AA) RA related information, information required for the operation corresponding to a release condition; (BB) Uplink signal, release request message, terminal location information