| 摘要 |
PURPOSE:To obtain plural branching optical signals having a sufficient margin by providing an optical distribution means using an optical coupler so as to branch an optical signal amplified with an optical signal amplifier means and outputting a branch ing optical signal to the transmitter. CONSTITUTION:The transmitter is provided with an optical signal amplifier means 1 which receives an exciting light oscillated from an exciting light source and a trunk line optical signal fi from one end and outputs a trunk line optical signal fo to other end via a rare-earth doped optical fiber 3 by using a stimulated light and with an optical distribution means 6 which uses the optical signal amplified by the optical signal amplifier means 1 and by branching with optical couplers 8-10, and outputs branching optical signals f1-f4. For example, let a gain of the optical signal amplifier 1 be 15dB and its saturation output be +10dBm, and a ratio of the trunk line optical coupler 7 be 50:50, when the trunk line optical signal fi inputted from a terminal T1 is -5dBm, the trunk line optical signal fo outputted from a terminal T4 is +7dBm and branching optical signals f1-f4 outputted from terminals T5-T8 are +1dBm. Thus, in this case, the transmitter acts like an optical branching amplifier and can be used as the optical distribution amplifier by changing the ratio of the trunk line optical coupler 7. Thus, plural branching optical signals having a sufficient margin are obtained. |
