Polarisationsregelung von bidirektional übertragenen Strahlenbündeln durch eine einzige Polarisationssteuerung

摘要

In an optical communication system where first and second transmitter devices (12, 16) bidirectionally transmit first and second signal beams through an optical fiber (11) and first and second receiver devices (13, 17) receive the second and the first signal beams, respectively, a polarization control system comprises a polarization control unit (21) between the optical fiber and the first transmitter and receiver devices and a controller (23) for controlling the polarization control unit by a detected signal produced by the first receiver device so as to supply the second signal beam to the first receiver device with a constant reference polarization state. The first signal beam may be an FDM signal beam. In this event, the second receiver device comprises tunable receivers (Rx1/100) which may be installed in a hub together with the second transmitter device and connected to terminal units through metal cables, Preferably, the first transmitter device generates the first signal beam with a polarization state adjusted either parallel or orthogonal to the reference polarization state. More preferably, the first and the second signal beams should have frequencies determined in consideration of polarization dispersion.