| 摘要 |
PROBLEM TO BE SOLVED: To allow the automatic switching from a wireless line to a general line (NTT) when the wireless line is unavailable for performing bidirectional communications via a center between a plurality of communication terminals connected to the wireless line. SOLUTION: In a communication device for bidirectional lines, a general telephone line 28 is connected to a communication terminal in addition to the wireless line 5 such that the wireless line can be used more preferentially than the general telephone line 28 except when a called communication terminal is busy or a speech channel is busy. When the called communication terminal is busy or when the speech channel is busy, the called communication terminal is automatically switched from the wireless line to the general telephone line 28. COPYRIGHT: (C)2008,JPO&INPIT
|
