Distributed temperature sensing measurement based on spontaneous Raman scattering in frequency domain

Concept of fiber spontaneous Raman scattering utilizing for distributed temperature sensing is presented. Chosen approach uses both backscattered Stokes as reference and anti-Stokes as detection signals. The analysis is carried out towards Stokes and anti-Stokes bands temperature dependence. In order to achieve best measurement accuracy influence of maximum modulation frequency on spatial resolution is verified. Analyzed technique allows to calculate temperature along the fiber with 5 m space precision and 1°C temperature precision. Simulations involve 200 m standard single mode fiber in temperatures in range < -5°C , 60 °C> with 2x1100 m reference fiber maintained in 27°C.