摘要 |
When a mobile station 200 is out of uplink synchronization, an efficient procedure is realized no matter whether a dedicated signature can be allocated. In a mobile communication system in which a base station 100 transmits a DL-SCH to a mobile station 200, when the mobile station 200 is out of uplink synchronization and detects resource allocation, the mobile station 200 performs a random access to the base station 100. When the base station 100 detects a signature by using a random access channel, it transmits a preamble response to the mobile station 200. When the mobile station 200 receives the preamble response, it transmits Message 3 to the base station 100. |