Low-cost Brillouin optical correlation-domain reflectometry involving merely one fibre amplifier

Brillouin optical correlation-domain reflectometry (BOCDR) is one of the fibre-optic distributed strain and temperature sensing systems. Conventionally, BOCDR has been implemented using three erbium-doped fibre amplifiers (EDFAs) to enhance the signal-tonoise ratio (SNR) of the measurement. However, the use of multiple EDFAs has restricted the size and cost efficiency of the system. In this work, the authors show that, among the three EDFAs previously employed, the one in the Stokes path plays the most important role in enhancing the SNR. Subsequently, they implement BOCDR using only one EDFA and demonstrate distributed strain sensing. The measurement error is also investigated as a function of the output power of a light source.