OPTICAL TRANSMISSION TERMINAL AND OPTICAL TRANSMISSION SYSTEM

摘要

PURPOSE:To obtain an optical transmission terminal in which an optical output of its light source is controlled at a point of time of mixing two optical signals so as to set the level of the output equal to a level of a modulation signal from another station in an incoming system of the optical transmission system by a frequency division multiplex access or code division multiplex access system where an optical signal from a concerned station and an optical signal from another station are mixed and the resulting signal is sent. CONSTITUTION:The system consists of a light source 5 generating an optical signal of a concerned station, an optical mix section 1 mixing the optical signal from the other station and the optical signal from the concerned station, and a detection section 3 extracting part of an output of the optical mix section 1 to detect at least a signal level of a modulation signal or a pilot signal level from the other station. Then an optical output or optical modulation of the light source 5 of the concerned station is controlled to change depending on the detected level by the detection section 3 and after the mixing, the level of the modulation signal from the other station is set equal to the level of the modulation signal from the concerned station.