Multiwavelength Linear-Cavity SOA-Based Laser Array Design for Multiparameter and Long-Haul Sensing

A multiwavelength linear-cavity laser array for long-distance sensing is designed and experimentally demonstrated. It is a semiconductor optical amplifier (SOA) integrating a 1 × N optical switch, formed by a 2 × 2 fiber loop mirror and fiber Bragg grating (FBG) as cavity ends. We investigate the laser system output characteristics and evaluate the sensor performance for different sensing distances incorporating the FBGs. The results show that this SOA-based laser sensor array possesses a dynamic sensing distance of up to 35 km at a 350-mA injection current. Stress/strain detection and reliable linear-cavity fiber laser sensing operation were successfully achieved.