OPTICAL DATA BUS TRANSMISSION SYSTEM

摘要

PURPOSE:To stabilize the transmission of the titled system by providing a means which detects the level of an optical signal fed from a master terminal station and a means which control the level of the transmitted optical signal in response to the output of said level detecting means at a slave terminal station and therefore keeping the level of signal received at the master terminal station at a fixed value by said level control means. CONSTITUTION:Plural slave terminal stations equipments are connected to a master terminal station equipment device via an optical fiber transmission line to form an optical data bus transmission system for an optical signal. A receiving part R1 and a transmitting part S1 are connected to a slave terminal X1 of said transmission system. Then the optical signal is converted into an electric signal by a photodetecting element 1 of the part R1 and amplified by a preamplifier 2 and a main amplifier 3 to be applied to the terminal X1 via an identifying circuit 4. In this case, the signal peak value is detected by a peak detecting circuit 6 and applied to a voltage control circuit 7. Then a driving circuit A of the part S1 which supplies the transmission data given from the terminal X1 is controlled by the output of the circuit 7. An optical signal corresponding to the reception level is transmitted to the master terminal station from a light emitting element B in order to always keep the reception level at a constant level at the master terminal station.