Raman-Assisted Brillouin Distributed Temperature Sensor over 100 km featuring 2 meter Resolution and 1.2°C Uncertainty

Raman assistance in distributed sensors based on Brillouin Optical Time-Domain Analysis (BOTDA) can significantly extend the measurement distance. In this work we have developed a 2 meter resolution long-range Brillouin distributed sensor that reaches 100 km using first-order Raman assistance. The estimated uncertainty in temperature discrimination is 1.2°C, even for the position of worst contrast. The parameters used in the experiment are supported by a simple analytical model of the required values, considering the main limitations of the setup.