| 摘要 |
PURPOSE:To realize the optical communication network with high reliability by detecting a reflection signal from an optical fiber connection section or the like and eliminating the signal so as to prevent mis-detection due to signal collision. CONSTITUTION:A coding circuit 31 of a terminal equipment 39 converts a transmission signal into a code series suitable for communication, the signal is converted into an optical signal by an E/O conversion circuit 24 and the result is sent to an optical fiber 10 through a demultiplexer/multiplexer element 22 and an optical coupler 21. The presence of a reflection signal, a delay time and an attenuation are recognized, a signal from the coding circuit 31 is delayed and amplified properly by a variable delay variable amplifier circuit 38, the result is subtracted from a signal from an O/E conversion circuit 23 at a subtractor circuit 36 to eliminate a reflecting signal component of the transmission signal from its own terminal equipment from the reception signal and only the signal component from other terminal equipment is inputted to a collision detection circuit 35. Thus, mis-detection of collision is not caused. |
