| 摘要 |
PURPOSE:To virtually eliminate the deterioration due to the detour interference, by subtracting electrically the detour interference component via the erase signal compounded through the erase signal compounding circuit and thus erasing the greater part of the interference component. CONSTITUTION:Owing to the back dispersion on the optical transmission line 1 or the end-face reflection at the joint area or the like, the partial electric power of the optical signal transmitted from the optical transmitters 11 and 12 is returned. And furthermore a part of the returned power detours into the optical receivers 21 and 22 via the optical branching filters 31 and 32 each. On the other hand, the detour interference component is electrically substracted from the received input signal sent from the transmitters 11 and 12 of the self-station and with the interference light added by means of the erase signals 141 and 142 which are compounded through the erase signal compounding circuits 61 and 62. As a result, the greater part of the interference omponent can be erased, thus virtually eliminating the deterioration due to the detour interference. |
