A mobile station (MS) performs a first random access procedure using a dedicated preamble for non-contention based random access on a first available random access channel (RACH) of a plurality of RACHs in time domain within a period that the dedicated preamble is valid. In addition, the MS performs a second random access procedure using the dedicated preamble for non-contention based random access on the first available RACH after the predetermined time window has expired in a case that a random access response to the transmitted preamble is not received within a predetermined time window monitoring for the random access response. The MS also transmits the dedicated preamble on a RACH allowed to transmit by the BS, where any one of the RACHs in frequency domain is allowed to be transmitted by the BS over a period of time that the plurality of RACHs are allocated to a single carrier.