| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the circuit scale, to improve the transmission efficiency and to decrease the processing time by utilizing a multi-frame phase of an input STM signal so as to contain information by a frame period of the received STM signal into one cell. SOLUTION: Received STM signals by a cell conversion circuit 11 are signals of plural series having the same multi-frame structure whose multi-phases are coincident with each other, a cell conversion circuit 11, a cell overhead provision circuit 12, a cell synchronization circuit 14 and a cell inverse conversion circuit 15 are provided to each channel, and a multi-frame phase detection circuit 16 is provided to the system as a means detecting a multi-frame phase of plural series signals. Each cell conversion circuit 11 contains information of one or plural multiframes, based on a detected multi-frame phase as a unit. Thus, when multi-frame phase for all channels can be established simultaneously when cell synchronization is established.</p> |
