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

摘要

When a mobile station device performs a random access for a handover, it is possible to reduce the time required for the handover. In a mobile station system, the mobile station device (200) uses one of predetermined signatures to communicate with a base station device (100) upon a random access. The base station device (100) selects the signature used for the random access by the mobile base station (200) upon the handover. The mobile station device (200) performs the handover by using the signature selected by the base station device (100). According to the type of the signature selected by the base station device (100), it is decided whether a handover completion message and a contention resolution have been transmitted/received.