WIRELESS COMMUNICATION SYSTEM, BASE STATION APPARATUS, MOBILE STATION APPARATUS, WIRELESS COMMUNICATION METHOD, BASE STATION APPARATUS CONTROL PROGRAM, AND MOBILE STATION APPARATUS CONTROL PROGRAM

摘要

A base station apparatus allocates a plurality of uplink component carriers and a plurality of downlink component carriers to a mobile station apparatus and uses the plurality of downlink component carriers to transmit/receive random access messages. The base station apparatus (3) comprises a random access control unit (1012) that performs a control of transmitting a signal, which indicates that a random access process started by the mobile station apparatus has succeeded, by use of one of the plurality of downlink component carriers allocated to the mobile station apparatus. The mobile station apparatus receives the signals of the plurality of downlink component carriers from the base station apparatus (3) and uses one of the uplink component carriers allocated by the base station apparatus (3) to start a random access process. When having detected, via one of the plurality of downlink component carriers, a signal indicating that the random access process has succeeded, the mobile station apparatus recognizes that the random access process has succeeded.