| 摘要 |
PURPOSE:To monitor a burst error rate accurately with a simple circuit, by forming an error detection unit of N-auxiliary bit, and using one of them as a parity check bit. CONSTITUTION:The output of a burst converting circuit 11 consists of succeeding frames, and auxiliary bits in each frame have logic which depends upon its use. One of every N auxiliary bits is set to 0 as a parity check bit and sent to an OR gate 13. A parity check bit counter 12 inputs only the auxiliary bits in each frame to count only bits having logic 1, and decides on whether the logic of the parity check bit should be set to 1 or 0, thereby sending the result to the gate 13. The logic of the parity check bit outputted from the gate 13 depends upon the logic of the counter 12. At a reception, side only the auxiliary bits are extracted from each frame and a parity check is made to perform accurate burst error rate monitoring. |
