| 摘要 |
PROBLEM TO BE SOLVED: To prevent data from being lost owing to a burst error generated nearby a specific position by deciding frame synchronism when a frame synchronizing word and a frame number word are both decided. SOLUTION: A frame synchronism deciding means 1 compares a PCM signal 21 after bit synchronization with a frame synchronizing word which is held inside to detect a signal whose bits are all or partially matching. Further, the presence of the frame at a normal position is evaluated and a frame synchronizing word establishment state signal 23 is outputted. A frame number deciding means 2 compares the received frame number word with a reference frame number word which is held while increased inside to evaluate whether all or some of the bits are matching, and the state value of the evaluation is outputted as a frame number word establishment state signal 24. A frame synchronism deciding means 3 outputs a frame synchronization establishment signal 26 indicating that frame synchronism is established on based on the state signals 23 and 24. |
