PASSIVE POINT-MULTIPOINT OPTICAL TRANSMISSION SYSTEM

摘要

PURPOSE:To avoid overlap of incoming optical signals from plural user terminals to the center equipment while suppressing a transmission efficiency to its minimum in respect to a passive point-multipoint optical transmission system constituted to modulate light transmitted from the center equipment and return the modulated light without arranging an active optical element in each user terminal. CONSTITUTION:The center equipment is provided with a light transmitting means 21 for time sharing, multiplexing and transmitting plural outgoing optical singnals to be sent to respective user terminals 30 and a light receiving means 22 for receiving incoming optical signals sent from respective user terminals 30, each user equipment 30 is provided with a light receiving means 31 for receiving an outgoing optical signal within a time area allocated to the terminal 30 itself and a light transmitting means 32 for modulating the outgoing optical signal itself or a part of the signal and transmitting the modulated signal as an incoming optical signal and at least one of the terminals 20, 30 is provied with a control means 24 for controlling the transmission timing of an outgoing optical signal or an incoming optical signal.