| 摘要 |
PURPOSE:To simplify the circuit constitution of a light intermediate repeating device by providing a synchronization circuit used in common for the branch circuit of a reception signal, and a code error rate count circuit in the light intermediate repeating device, and counting selectively the code error rate of respective transmission line. CONSTITUTION:In a system, in which the plural transmission lines are constituted in one way or in two ways, one transmission line is assumed to be a master transmission line, and the others to be slave transmission lines, and the slave transmission line does not synchronize the reception signal in the respective light intermediate repeating device, and only branches 32, 33 the reception signal, and transmits one of outputs to the next light intermediate repeating device. At the same time, it outputs the other output to the light intermediate repeating device of the master transmission line, and the master transmission line side counts the code error rate by selecting 71 and synchronizing 31 the branched reception signal from the slave transmission line according to necessity, and transfers the said information to a light terminal station repeating side by using the master transmission line. Thus, the circuit constitution of the light intermediate repeating device can be drastically simplified. |
