基于SOA光纤环形激光器的分布式声传感系统

Distributed acoustic sensing system based on SOA fiber ring laser

为了降低传统分布式声学传感器(DAS)系统复杂度并提高信噪比(SNR),提出了一种基于半导体光放大器的光纤环形激光器(SOA-FRL)的DAS系统。该系统用SOA-FRL取代了传统的DAS系统中的窄线宽激光器和脉冲调制器,实现了高稳定的光脉冲输出;采用双脉冲外差探测方法,实现了精确的声信号探测和声源定位。实验结果表明:在频率为1 kHz、幅值为1.14 rad的声信号作用下,所提系统的解调SNR高达38.25 dB,空间分辨率为12 m。

In order to reduce the complexity of the traditional distributed acoustic sensor(DAS)system and improve the signal-to-noise ratio(SNR),a DAS system based on a fiber ring laser(SOA-FRL)based on a semiconductor optical amplifier is proposed.This system uses SOA-FRL to replace the narrow linewidth laser and pulse modulator in the traditional DAS system,and realizes the highly stable optical pulse output.The double pulse heterodyne detection method is used to achieve accurate sound signal detection and sound source location.The experimental results show that the demodulation SNR of the proposed system is as high as 38.25 dB and the spatial resolution is 12 m under the action of the acoustic signal with frequency of 1 kHz and amplitude of 1.14 rad.