| 摘要 |
PURPOSE:To select and call out an opposing party freely and to enable a portable ratio communication of 1:1 which is impossible for side reception between individuals, by making mutual selective connection through the use of code division multiplex communication system and making correspondence through the use of frequency division multiplex communication system. CONSTITUTION:When an address of opposing party wishing correspondence from an input keyboard 8 is inputted, a search reception circuit 4 is in operating state with an operation mode controlling circuit 7 to retrieve a vacant communication channel. Through this retrieve, a transmission/reception circuit 3 is in transmission mode, and a vacant channel list is transmitted at the opposing address at an MODEM circuit 6 at the same tme, and the circuit 3 is at reception mode for waiting. When the transmitted electromgagnetic waves for itself are received at the reception side, the transmitted information is picked up at the circuit 6 and the vacant channel list is formed via an operating mode control circuit 7, and one channel in common with the list of the caller is selected for transmission. The caller receives it and sets the circuit 3 to a designated channel for correspondence. |
