| 摘要 |
PROBLEM TO BE SOLVED: To simplify the configuration and the operation by controlling the selection as to whether an S1 byte separated from an STM-N signal or an S1 byte corresponding to the quality of an in-equipment synchronization clock is multiplexed. SOLUTION: In the case of synchronous communication, an S1 byte selector 106a of a control circuit 104a selects an S1 byte obtained by converting a quality level 14 from a clock quality monitor circuit 105a and gives the selected byte to an SOH multiplex circuit 103a. The circuit 103a multiplexes a pointer generated by a clock signal selected by the circuit 105a and the S1 byte. In the case of adopting the subordinate synchronization system, a selector 106b of a control circuit 104b is controlled to output the S1 byte extracted by an SOH separate circuit 101b to an SOH multiplex circuit without any modification and the operation of a quality monitor circuit is omitted. A pointer generated by the line extract clock and the S1 byte are multiplexed by the circuit 103b in this channel. |
