WIRELESS COMMUNICATION SYSTEM, MOBILE STATION APPARATUS, BASE STATION APPARATUS, WIRELESS COMMUNICATION METHOD, AND INTEGRATED CIRCUIT

摘要

Efficient transmission and reception of a random access response message is performed between a base station device and a mobile station device. When a random access preamble is transmitted from a primary cell, the mobile station device monitors a first control channel of the primary cell. When the random access preamble is transmitted from a secondary cell, the mobile station device monitors a second control channel of the secondary cell. When a random access response identifier is detected, the mobile station device receives a random access response message that is allocated to a data channel. When the random access preamble is received, the base station device transmits the random access response identifier on the first control channel and the second control channel of a downlink corresponding to an uplink on which the random access preamble is received, and transmits the random access response message on the data channel.