Dual pulse heterodyne distributed acoustic sensor system employing SOA-based fiber ring laser

Distributed Acoustic Sensor (DAS) has potential in applications such as hydroacoustic detection. In this paper, a dual-pulse heterodyne distributed acoustic sensor system using semiconductor optical amplifier (SOA)-based fiber ring laser (FRL) is proposed. Unlike the previous DAS configurations, SOA-based FRL replaces narrow linewidth (NLL) and pulse modulator, reducing costs simplifying system. The demonstrated theoretically validated experimentally. adaptability of been experiments. Using detection method, responds well to achieves accurate demodulation positioning. A high signal-to-noise ratio (SNR) 42.51 dB at 3 kHz result. system’s frequency range 5 Hz with spatial resolution 12 m. proposed approach shows broad application prospect for low-cost, large-scale, high-SNR maritime surveillance.