| 摘要 |
PURPOSE:To improve the transmission efficiency for transmission by making a signal to the other station by making a characteristic different in accordance with the contents, superposing it on a signal to the own station and sending it out, and to prevent the deterioration of the transmission performance by demultiplexing the signal at every characteristic and processing it in the other station. CONSTITUTION:Each station 2 divides a signal sent from the other station by an optical fiber 3 by a branch means 5, and sends to a delaying means 7 and a demultiplexer 8. The demultiplexer 8 leads light beams of wavelength lambda1, lambda2 to photoelectric converters 10, 13, respectively, and a pulse sending-out device 12 sets that which is larger in average power as an input signal to the own station. The signal to the own station is sent to a circuit connection control part 16, and in the case of sending it to the other station, electro-optical converters 11, 14 are used and a signal is made by wavelength being different from that of an input to the own station. When the input is addressed to the other station or communication is unnecessary, a signal is made by the same wavelength as the time of an input. A generating signal is coupled by a multiplexer 9, and thereafter, multiplexed with a branch signal passing through the delaying means 7 by a coupling means 6. The delay time by the means 7 is set so that burst signals in each optical signal are superposed at the time of this multiplexing, and the light intensity of the signal made by electro-optical converting means 11, 14 is adjusted so as to become larger than an output of the delaying delaying means. A central station 1 controls the communication. |
