DEVICE AND METHOD FOR HIGH PRECISION FIBER-OPTIC TEMPERATURE PROFILE MEASUREMENTS IN LONG LENGTH AREAS

摘要

A high precision fiber-optic device and method are developed for measuring a temperature profile in a long length area. The temperature profile is derived based on a ratio between the intensities of anti-Stokes Raman and Stokes Raman backscattered components. The power output of the amplified pulsed optical radiation delivered to the sensing optical fiber via a reference optical fiber, is controlled such as to maintain a substantially fixed intensity level of the anti-Stokes Raman component of the optical radiation back scattered from the reference optical fiber. Controlling the output power of the of the amplified pulsed optical radiation is carried out based on a feedback representative of the intensity level of the anti-Stokes Raman component of the optical radiation back scattered from the reference optical fiber.