| 摘要 |
PURPOSE:To simplify a light source, and also, to miniaturize an external form by providing a transmission power source being capable of wavelength modulation, for sending out successively the wavelength corresponding to each channel by time division. CONSTITUTION:A station side 40 uses a semiconductor laser 11 of a single transmission source having a comparatively wide variable wavelength range, selects a wavelength corresponding to each channel and sends it out successively by a time division by a multiplexing circuit 9, and an optical signal being equivalent to wavelength diviation multiplexing is sent out to a subscriber side 41 from an optical fiber transmission line 14 by a single light source. In the subscriber side 41, the optical signal is demultiplexed to each wavelength by an optical demultiplexer 15, photodetected by photodetecting parts 25, 26 and 27, a part of the light beam received by an optical modulator 33 is remodulated and sent back to the station side 40, at this remodulated light beam is received, the station side 40, and bidirectional communication is executed. In such a way, many light sources are not required, and the transmission equipment is miniaturized. |
