MOBILE STATION DEVICE, BASE STATION DEVICE, COMMUNICATION SYSTEM, COMMUNICATION METHOD, AND PROGRAM

摘要

Provided is a mobile station device which can increase the success ratio and reduce a communication delay when transmitting a dedicated preamble from the mobile station device to a base station device by using a random access channel (RACH). The mobile station device performs random access to the base station device by using a dedicated preamble. The mobile station device transmits a first message by using the dedicated preamble and again transmits the first message using the dedicated preamble during a period (a random access response reception-uncertain period) when the base station device may transmit a second message as a response to the first message.