Technique for measuring longitudinal distribution of Raman gain characteristics in optical fibers

This paper proposes a novel technique for measuring the longitudinal distribution of the Raman gain characteristics in concatenated single-mode optical fibers. This technique has an attractive advantage in that the Raman gain efficiency in concatenated optical fibers can be evaluated individually. We describe a measurement principle for obtaining the Raman gain efficiency distribution in optical fibers. We carried out laboratory and field measurements based on this principle, and confirmed that the Raman gain efficiency distribution could be measured easily and accurately.