| 摘要 |
PURPOSE:To improve the reliability of a system by receiving a pilot signal at a pilot signal reception section via a polarized wave controller disposed on the outgoing terminal of an optical transmission section and detecting the polarized wave fluctuating state occurring in an optical fiber and holding the polarized wave of a pilot signal light to be constant. CONSTITUTION:A binary FSK is applied with, e.g. 20 signal light sources 3 of a CATV center 1 and an outgoing light is branched into plural waves after frequency multiples at a star coupler 4. One of branched FDM signal beams 14 is sent via a polarized controller 5 and sent to a multiple dwelling house 11 apart from the center 1 by, e.g. 20km through a single mode optical fiber 8. After the signal light 14 is branched (9) and distributed to each reception terminal equipment through a polarized wave maintaining optical fiber 16. Each terminal equipment selects and receives the optional channel of a signal light 14 of 20 channels. Then a pilot signal 13 outgoing from the pilot signal light source 10 is made incident on the polarization wave maintaining type pilot optical fiber 17 and sent to the center 1 via a bus 8. |
