| 摘要 |
PURPOSE:To perform high-density frequency multiplex transmission by using one light carrier by mixing sent signal light and local oscillation light and then branching them. CONSTITUTION:At a repeater station B, the light signal which is sent optically from a transmitting station A and the local oscillation light which is distributed from it and outputted from a common local oscillation light source 5 to all subscribers C are mixed by an optical mixer 6 and then branched by an optical branching device 7, so that the light is sent to the respective subscribers C. Each subscriber C converts the light signal sent from the repeater station B into an electric signal after heterodyne detection by a photodetector 8, passes the signal through an amplifier 9, etc., and sorts it by channels through electric filters (BPF) 10-1-10-k, and demodulators(DEMOD) 11-1-11-k demodulate them respectively. |
