Distributed optical fiber sensor

A distributed optical fiber sensor which uses an optical fiber as a sensor, comprising:

• a light source for generating a light that enters the optical fiber;
• a Brillouin measuring unit for measuring a Brillouin frequency shift amount caused by a strain and a temperature generated in the optical fiber by using a Brillouin scattering phenomenon based on light that exits the optical fiber;
• a Rayleigh measuring unit for measuring a Rayleigh frequency shift amount caused by the strain and temperature generated in the optical fiber by using a Rayleigh scattering phenomenon based on light that exits the optical fiber;
• and
• a calculation unit for calculating the strain and temperature generated in the optical fiber based on the Brillouin frequency shift amount measured by the Brillouin measuring unit, estimating the Rayleigh frequency shift amount based on the measured Brillouin frequency shift amount and calculating the Rayleigh frequency shift amount measured by the Rayleigh measuring unit.