| 摘要 |
PURPOSE:To attain time synchronization control at a low cost with simple constitution by using a time slot of signaling bits of a digital transmission network to send a time synchronizing signal and allowing a receiver side clock device to be subjected to subordinate synchronization with this time synchronizing signal. CONSTITUTION:A time synchronizing signal insertion means 2 of a sender side data communication equipment 10 uses a time slot of signaling bits to insert a time synchronizing signal 9 outputted from a sender side clock device 3 to a data communication signal and sends the resulting signal to a communication line 4 of a digital transmission network. A time synchronizing signal detection means 5 of a receiver side data communication equipment 11 detects the time synchronizing signal 9 from the received data communication signal and extracts the signal, and a time synchronization means 6 allows a count clock timing of the clock device to be subject to subordinate synchronization with the time synchronizing signal 9, the receiver side clock device 7 receives the count clock subject to subordinate synchronization and outputs time information synchronously with the sender side clock device 3. Thus, the time synchronization control is attained at a low cost with simple equipment constitution. |
