Patent ID: 8879512

Claim:
A mobile station apparatus in a communication system performing non-contention based random access to a base station apparatus, the mobile station apparatus comprising: a receiver configured to receive, from the base station apparatus, a dedicated preamble ID which is used for first transmission and retransmission, and which is uniquely assigned by the base station apparatus to avoid a preamble contention among a plurality of mobile station apparatuses, and random access resource information which is used for first transmission and retransmission; and a transmitter configured to: transmit, to the base station apparatus via a resource specified by the random access resource information, a preamble generated by using the dedicated preamble ID, and retransmit the preamble to the base station apparatus via the resource in a case that a response to the preamble fails to be received after the preamble is transmitted within a predetermined period which is determined based on the random access resource information.