| 摘要 |
PURPOSE:To prevent a phenomenon that a signal loops between a pair of optical remote repeaters by connecting two transmission paths through a pair of optical fibers by the pair of optical fiber remote repeaters equipped with optical communication control circuits. CONSTITUTION:A gate control circuit 12a disables a line driver 11a, that is to say, makes it high-impedance when the changing point of the output signal of a line receiver 5a out of the changing points of the output signal of the line receiver 5a and the output signal of a photoelectric converting element 10a exists formerly in a fixed time. By an optical communication control circuit 41a, a D flip flop 32a holds the output signal level at a Q output in the timing of the changing point of the output signal of the line driver 5a and continues to hold it to the next changing point of the output of the line driver 5a only when the gate control circuit 12a disables the line driver 11a. Thus, the loop phenomenon in a pair of remote repeaters 31a and 31b can be prevented. |
