Passive optical telecommunicationssystem

摘要

In a passive optical telecommunications system, an electric carrier signal is DPSK-modulated in the upstream transmission, whereafter the electric signal modulated in this way effects the intensity modulation of the transmitted light; in the downstream signal transmission, the transmitted light is intensity-modulated by a preferably scrambled NRZ baseband signal. The carrier signal is derived from the regenerated receive clock signal of the local device by frequency multiplexing.