Patent ID: 8004751
Filing Date: 2011-08-23
Classification: H01S,H04B

Abstract:
1. A wavelength division multiplexing optical transmission system provided with a first optical device connected to one end of a transmission line, for transmitting wavelength division multiplexing signal light to the transmission line, and a second optical device connected to an other end of the transmission line for receiving wavelength division multiplexing signal light that has propagated through the transmission line and been subjected to distributed Raman amplification, wherein the wavelength division multiplexing optical transmission system comprising: a monitor that monitors transmission line input power for a plurality of lights which are transmitted from one of the first and second optical devices and transmission line output power for the plurality of lights which are received by the other optical device, the plurality of lights having different wavelengths than the wavelength division multiplexing signal light being transferred between the first and the second optical devices via the transmission line; a calculating circuit that calculates a transmission line loss in each wavelength corresponding to the plurality of lights, by using values of transmission line input power and transmission line output power for the plurality of lights monitored by the monitor, and specifies a type of the transmission line based on a loss wavelength characteristic that can be estimated from the calculation result; a pump light source that supplies to the transmission line, pump light for performing distributed Raman amplification on the wavelength division multiplexing signal light propagating through the transmission line; and a controller that controls the pump light source so that an output wavelength characteristic of wavelength division multiplexing signal light that has been subjected to distributed Raman amplification, and which is output from an other end of the transmission line, becomes a target output wavelength characteristic, corresponding to the type of the transmission line specified by the calculating circuit.