Abstract: A mobile communication system involves a mobile space defined in, for example, a train, and mobile terminals available in the market. When the mobile terminals are used in the mobile space, the system provides them with value-added services exclusive to the mobile space. The system also includes existing base stations each controlling a fixed radio zone that covers a predetermined area, and a mobile base station for controlling a mobile radio zone allocated to the mobile space where the mobile terminals are used. The mobile base station serves as a mobile base station to communicate with the existing base stations, and as a fixed base station to communicate with the mobile terminals when the mobile terminals are in the mobile radio zone. Also provided is a method of controlling such a system.

Abstract: A mobile communication system intended to control switching of a voice channel (handover) when a radio zone boundary is traversed; to quickly detect an unlawful mobile station; to equalize load if processing at a base control station is congested; and to constitute a location area for reducing control channel load due to simultaneous paging. The user is notified that a handover factor has been detected, and a switch enables the user's intention to be transmitted to the network to switch or stop the voice channel in accordance with the will of the mobile station user who is making the call. User accumulated call accounting information is totaled by the network and the mobile station individually for comparison to detect an unlawful mobile station. The number of base stations controlled by the base control station is, in real time, dynamically, changed to correspond to the state of congestion.

Abstract: A mobile communication system intended to early detect unlawful mobile station. User information about accumulated call account is totaled by the network and the mobile station individually so as to be subjected to a comparison to found an unlawful mobile station.