Impact of Loss variations on Double-Ended Distributed Temperature Sensors Based on Raman Anti-Stokes Signal Only

We present a theoretical and experimental analysis of the sensing capabilities of Raman-based distributed tempera- ture optical Þber sensor (RDTS) systems using only the anti-Stokes (AS) component in loop conÞguration. In particular, the effects of time- and wavelength-dependent losses on the sensor performance are thoroughly investigated under different experimental condi tions. As expected from the developed theory, experimental results demonstrate that using the loop AS-light only approach in RDT systems can correct the impact of local and wavelength-dependent losses on the final temperature measurements, with the simple use of an internal calibration Þber spool at a known temperature value. Signal-to-noise ratio and temperature resolution analyses of the AS-only RDTS point out an improved temperature resolution in comparison to standard RDTS systems in loop conÞguration.