Abstract: A mobile communications system includes a control station that identifies a base station zone serving as a communications area of a base station and performs position registration of first mobile stations which belongs to the base station; and a relay terminal station that relays radio communications between the base station and a second mobile station, the second mobile station being located outside the base station zone and inside a relay terminal zone. Further, the second mobile station sends a position registration request signal to the base station via the relay terminal station; the base station receives the position registration request signal and transfers the received position registration request signal to the control station; and, after completing the position registration, the control station sends a position registration acknowledgement signal to the second mobile station via the base station and the relay terminal station.

Abstract: A repeater including a first wireless unit that performs transmission and reception using a frequency for communicating with a base station and a second wireless unit that performs transmission and reception using a frequency for communicating with a mobile station performs a follow-up communication after broadcast communication. The repeater causes, while the second wireless unit transmits a broadcast communication signal (TCH (voice data)) to the mobile station, a transmitter (TX) provided on the first wireless unit to regularly transmit a switching signal (UI signal (for designating a direct communication wireless channel, and for setting a direct communication simplex call) for switching the mobile station to a broadcast communication channel.

Abstract: A mobile communications system includes a control station that identifies a base station zone serving as a communications area of a base station and performs position registration of first mobile stations which belongs to the base station; and a relay terminal station that relays radio communications between the base station and a second mobile station, the second mobile station being located outside the base station zone and inside a relay terminal zone. Further, the second mobile station sends a position registration request signal to the base station via the relay terminal station; the base station receives the position registration request signal and transfers the received position registration request signal to the control station; and, after completing the position registration, the control station sends a position registration acknowledgement signal to the second mobile station via the base station and the relay terminal station.

Abstract: A repeater including a first wireless unit that performs transmission and reception using a frequency for communicating with a base station and a second wireless unit that performs transmission and reception using a frequency for communicating with a mobile station performs a follow-up communication after broadcast communication. The repeater causes, while the second wireless unit transmits a broadcast communication signal (TCH (voice data)) to the mobile station, a transmitter (TX) provided on the first wireless unit to regularly transmit a switching signal (UI signal (for designating a direct communication wireless channel, and for setting a direct communication simplex call) for switching the mobile station to a broadcast communication channel.