| 摘要 |
PURPOSE: To reduce the circuit scale by using a radio channel for calling required for connection to other radio telephone set in the case of extension call and using a radio channel required for the connection to a master set in the case of an external line call and to relieve the load of a circuit control section in the master set. CONSTITUTION: A master set is provided with an external interface 101 accommodating an external line (public line), a line control section 102 conducting connection control between an external line and an extension, a radio extension interface 103 accommodating a radio extension, and an extension interface 104 accommodating an extension. The radio extension accommodates radio telephone sets 105-107 and the extension accommodates an extension telephone set 108 via a wired line. In the case of an extension call, a radio channel requiring the connection to other radio telephone set is used and in the case of an external line call, the radio channel required for the connection to the master set is used, then the communication in the system is conducted directly between radio telephone sets and the communication with an external line is conducted via the master set. |
