| 摘要 |
PURPOSE:To suppress the increase of the number of a frames required till the frame synchronization is established by providing plural frame synchronization establishing circuits each consisting of a synchronizing word detection circuit and a frame synchronization discrimination circuit in pairs and deviating the operating start time of each properly. CONSTITUTION:A comparator 1 receiving a reception data detects a synchronizing word pattern in existence in the data and generates a coincidence pulse 3 in 1 bit data width. A frame synchronization discrimination circuit 15 receiving a synchronizing word pulse 11 sends a synchronizing word detection pulse 17 to a synchronization establishment control circuit 21 and reaches the standby state for a synchronizing word pulse to be reached after one frame. A coincidence pulse 4 from a comparator 2 passes through an AND gate 10 to be a synchronizing word pulse 12, which is sent to a frame synchronizing discrimination circuit 18. The frame synchronizing discrimination circuit 16 receiving the synchronizing word pulse 12 sends a synchronizing word detection pulse 18 to the synchronization establishment control circuit 21 and reaches the standby state for the synchronizing word 12 to be reached after one frame. |
