Abstract: A method for performing roaming in a dual mode terminal, which includes a first wireless communication module corresponding to a first communication network and a second wireless communication module corresponding to a second communication network, is disclosed. The method comprises acquiring a public land mobile network (PLMN) identifier by camping on the first communication network; determining whether connection to the first communication network is roaming by comparing roaming decision information included in the PLMN identifier with roaming decision information stored in the dual mode terminal; turning off the second wireless communication module if it is determined that connection to the first communication network is roaming; and transmitting and receiving a signal to and from the first communication network.

Abstract: A method for performing roaming in a dual mode terminal, which includes a first wireless communication module corresponding to a first communication network and a second wireless communication module corresponding to a second communication network, is disclosed. The method comprises acquiring a public land mobile network (PLMN) identifier by camping on the first communication network; determining whether connection to the first communication network is roaming by comparing roaming decision information included in the PLMN identifier with roaming decision information stored in the dual mode terminal; turning off the second wireless communication module if it is determined that connection to the first communication network is roaming; and transmitting and receiving a signal to and from the first communication network.

Abstract: A method of controlling an operation of a mobile base station that is linked to a mobile communication system via a wireless relay channel includes an information acquiring step of acquiring estimation-purpose base information for estimating a condition of radio interference between the mobile base station and one or more other base stations, the acquisition of the estimation-purpose base information being made by the mobile base station and involving measurement of a physical property responsive to a current position of the mobile base station, an estimation step of estimating the condition of radio interference based on the acquired estimation-purpose base information, and a control step of controlling an operation of the mobile base station based on the estimated condition of radio interference.

Abstract: A mobile communication network forming device of the present invention comprises: a base station function section that forms a wireless zone, subscriber switching means that chiefly perform in-range management of mobile stations that are in range of the wireless zone and connection exchange between mobile stations that are in range of the wireless zone, and satellite gateway switching means that perform mutual connection between a mobile station which is in range of a wireless zone and other communication network through a communication satellite.

Abstract: A method of controlling an operation of a mobile base station that is linked to a mobile communication system via a wireless relay channel includes an information acquiring step of acquiring estimation-purpose base information for estimating a condition of radio interference between the mobile base station and one or more other base stations, the acquisition of the estimation-purpose base information being made by the mobile base station and involving measurement of a physical property responsive to a current position of the mobile base station, an estimation step of estimating the condition of radio interference based on the acquired estimation-purpose base information, and a control step of controlling an operation of the mobile base station based on the estimated condition of radio interference.

Abstract: The ground base station informs an in-level for the ground system, an out-level from the ground system, a timer value and an edge information indicating the edge of the service area, in addition to the broadcast information. It assumes that the mobile station MS moves from position 31 to zone 26 at the edge in the service area, and then moves to position 33. At the position 31, when the received field strength of the ground system decreases, the edge information is not detected, so that the mobile station MS does not switch the communication mode to the satellite system immediately by setting the timer value to three minutes. At position 32, the edge information is detected, so that the mobile station MS sets the timer value to one minute, and sets the out-level to a lower value than the general value. When the field strength is equal to or less than the out-level even after the passage of one minute, the mobile station MS switches the communication mode to the satellite system.