| 摘要 |
PURPOSE:To attain sure and stable bi-diretional relay operation by adding a switching device to a circuit being the combination of light emitting device and photodetector correspondingly arranged to each optical transmission line to be relayed and a bi-directional amplifier responding in the direction of an optical signal. CONSTITUTION:An optical signal a1 irradiated from the 1st transmission line F1 is received by the 1st combined device and detector for light emission and reception and converted into an electric signal a2. This signal a2 is impressed to an amplifier AMP through a switching device S1 and an amplified electric signal a3 is outputted. This signal a3 is applied to the 2nd device and detector D2 for light emission and reception via a switching device S2, transduced into an optical signal a4, this signal a4 is fetched to the 2nd optical transmission line F2 and retransmitted. On the other hand, when the optical signal a1' is irradiated from the transmission line F2, the switching devices S1, S2 connect the device and detector D2 to the input side of the amplifier AMP and the device and detector D1 to the output side of the amplifier AMP through the interlocking of switching mechanisms S1', S2'. Thus, the signal a1' from the transmission line F2 is fetched to the transmission line F1 as an optical signal a4' from the device and detector D1 through a nearly opposite path and retransmitted. |
