AN OPTICAL FIBRE AMPLIFIER WITH COUPLING OF PUMP ENERGY FROM SEVERAL PUMP SOURCES

摘要

An optical fibre amplifier having one or more active fibres so coupled to an optical transmission line that each of the active fibres has at least one input for a pump signal. The active fibres are adapted to amplify an optical signal at a first wavelength at stimulated emission, when optical energy is added in the form of a pump signal at a second wavelength. The pump signals are provided by means of pump lasers adapted to emit energy at the second wavelength. The optical fibre amplifier has an optical combination network with a plurality of inputs coupled to respective pump lasers and adapted to receive energy from these. The outputs of the combination network are coupled to the pump signal inputs on the active fibres, said network being adapted to combine the optical energy added from the pump lasers so that the optical energy on each one of the outputs of the combination network originates from several pump lasers. Drop-out of a pump laser will cause the optical signal on several outputs on the combination network to be reduced, but complete drop-out of optical energy on an output is obviated.