OPTICAL SIGNAL TRANSMISSION METHOD

摘要

PURPOSE: To improve the noise characteristic at reception of an optical signal by applying optoelectric conversion to an optical signal from upstream sent through an optical transmission path at a light receiving section provided at one terminal of each optical multiplexer of two transmission stations or more and controlling a level of an optical signal sent from each transmission station to each optical multiplexer in response to the electric signal so as to regulate a level of an output signal automatically thereby allowing a reception station to receive optical signals from the transmission stations as the same intensity. CONSTITUTION: A light receiving section 8 is provided to one terminal of an optical multiplexer 4 of each transmission station 2. Then an optical signal sent from an upperstream of an optical transmission path is received by a light receiving section 8 of a downstream transmission station 2 of a downstream to conduct photoelectric conversion and a level of an optical signal sent from the transmission station 2 to the optical multiplexer 4 according to the electric signal is controlled. Thus, noise characteristic at reception by a light receiving device 7 is improved by controlling levels of optical signals sent from the two transmission stations 2 or over and received by the light receiving device 7 of the reception station 6 to be identical to each other.