Raman gain distribution measurement employing reference optical fiber

This letter proposes a novel technique for evaluating the longitudinal distribution of the Raman gain characteristics in optical fibers connected to a reference optical fiber with a known Raman gain efficiency. This technique can evaluate the Raman gain efficiency in test fibers using a simplified experimental setup. We performed experiments on various test fibers and confirmed that their Raman gain efficiency can be obtained easily and accurately by employing a reference fiber.