| 摘要 |
PROBLEM TO BE SOLVED: To provide a base station device which can more efficiently make communications by allocating a signature to other mobile station devices, even in the term of validity of the signature, between the base station device and the mobile station device.SOLUTION: When determining it is necessary to make a mobile station device perform random access, a base station device determines whether or not an unused signature exists. Then, the base station device determines term of validity in which the mobile station device can use the signature and calculates termination time of the term of validity. And, the base station device includes the signature and the calculated termination time in a random access preamble allocation message to transmit them to the mobile station device. The mobile station device extracts the signature and the termination time from the random access preamble allocation message, and determines a random access channel which can transmit the random access preamble containing the signature on the basis of the extracted termination time. |
