| 摘要 |
PURPOSE:To perform synchronization as to time even when plural frequencies can not be used for one line by using a code sequence which are not normal data transmission codes as a synchronized signal by a synchronizing signal generator and a synchronizing signal receiver and also using a modulator/ demodulator for data transmission to carry out transmission. CONSTITUTION:A signal which is not normal data transmission codes is used as codes for the synchronizing signal outputted from the synchronizing signal generator 12. A signal changeover switch 13 is placed as shown in a diagram in normal data transmission. At this time, data is transmitted to the synchronizing signal reception part 16 as well, but synchronization is not performed. When the synchronization is performed, the switch 13 is placed on the opposite side and the synchronizing signal is outputted by the synchronizing signal generator 12. This signal is transmitted to the synchronizing signal reception part 16 to synchronize synchronizing device 17. At this time, the synchronizing signal is transmitted to a reception part 15 for data transmission signal, but this codes are not received as data. |
