摘要 |
PROBLEM TO BE SOLVED: To provide communication services, with which the high speed property of light is effectively utilized, to a large number of subscribers connected to a ring-shaped optical fiber transmission line while using a one-wavelength transmission system, which maintenance/management is facilitated. SOLUTION: A central station installing device 1 and a plurality of subscriber installing devices 2a-2i are connected in the shape of ring by an optical fiber transmission line 3. In the central station installing device 1, the signal light pulse stream of high speed is generated and transmitted to the optical fiber transmission line by multiplexing the signal light pulse stream of low speed in the time division manner in an optical region. In a plurality of subscriber installing devices 2a-2i, the received optical pulse of a prescribed time slot is branched out of the optical time division multiplex signal light pulse stream received from the optical fiber transmission line in the optical region and received as a signal light pulse stream of low speed, and the transmitted optical pulse of low speed is inserted to the same time slot in the optical region and transmitted to the optical fiber transmission line 3 as an optical time division multiplex signal light pulse stream of high speed. |