Communication terminal, the main device, and parent-child telephone system construction method

摘要

PROBLEM TO BE SOLVED: To provided a technology to more easily connect communication terminals.;SOLUTION: An extension phone system includes a plurality of cellular phone terminals 1-1 to 1-4. The cellular phone terminal 1-1 which has the best radio environment in a cellular phone network 2 becomes a master device, and accommodates the cellular phone terminals 1-2 to 1-4 as slave devices through a wireless LAN 3. The cellular phone terminal 1-1 connects the cellular phone terminals 1-2 to 1-4 to the cellular phone network 2 through the wireless LAN 3. Thereby, the cellular phone terminal 1-1 having the best radio environment in the cellular phone network 2 and serving as the master device and the plurality of cellular phone terminals 1-1 to 1-4 constitute the extension phone system, so that each of the cellular phone terminals 1-2 to 1-4 which have a poor radio environment in the cellular phone network 2 can perform satisfactory communication with the cellular phone network 2.;COPYRIGHT: (C)2010,JPO&INPIT