Optical transmission path monitoring system

摘要

Terminal equipment of a wavelength-division-multiplexing optical transmission system is provided with a monitoring apparatus for monitoring optical transmission paths with an OTDR. For this monitoring, OTDR probe lights of different wavelengths are allocated to optical fibers and optical amplifier-repeaters, which are elements constituting the optical transmission paths. Further, different wavelengths are allocated to OTDR probe lights between the up-link and the down-link. A wavelength that makes the wavelength dispersion negative over the optical transmission paths (usually the shorter-wavelength side than the zero-dispersion wavelength of the optical transmission paths) is allocated to the OTDR probe light for optical fiber monitoring, and a wavelength longer than 1550nm is allocated to the OTDR probe light for optical amplifier-repeater monitoring.