Multiplexed strain sensor using fiber grating-tuned fiber laser with a semiconductor optical amplifier

A novel fiber Bragg grating sensor system using a fiber laser with a semiconductor optical amplifier as a gain medium is proposed. The inhomogeneous broadening property of the semiconductor optical amplifier is used to generate multiple wavelength operation, which was not possible in an erbium-doped fiber laser due to the homogeneous broadening property. Using a semiconductor optical amplifier, the sensor system can involve multiple point sensor heads, which is an eight-point sensor in the initial experiment.