Recent progress in distributed Brillouin scattering fiber sensors (Invited)

An overview of recent progress in the field of distributed fiber-optic sensors based on stimulated Brillouin scattering (SBS) is presented. SBS sensors provide distributed measurements of temperature and strain, in which every segment of standard fiber serves as a sensing element. The fundamental measurement configuration was first proposed in the late 1980's, and commercial systems are available since the 1990's. The technology is being adopted by the oil and gas, energy, civil engineering and aerospace sectors. Examples of several recent and significant advances include the extension of the measurement range beyond 100 km; cm-scale spatial resolution over km-scale lengths; range and spatial resolution improvement, using elaborate radar coding techniques; the use of polarization-maintaining fibers to differentiate between strain and temperature; dynamic measurements of fast (similar to millisecond) events; and finally performance modeling and the emergence of guidelines and figures of merit.