基于光频调节的干涉型光纤水听器相位补偿检测方法

提出了一种基于光源频率调节的干涉型光纤水听器主动相位补偿的信号检测方法。详细介绍了该方法的基本检测原理,对信号解调误差进行了理论分析与仿真。为了验证该方法的可行性,搭建了实验系统,并编写了实时的信号采集、处理程序,对某一干涉型光纤水听器的声压灵敏度进行了测试。在频带20 Hz-1.3 kHz上,平均声压灵敏度为-162.2 dB(0 dB=1 rad/μPa),波动小于±0.8 dB,与采用相位载波调制解调方法测量的结果基本吻合。实验结果证明该方法是有效的。由于传感部分不含有源器件,便于实现全光纤化,且解调算法简单、检测频带宽,该方法能被广泛应用到各种干涉型光纤传感器的信号检测当中。

Phase Compensating Detection Method of Interferometric Fiber-Optic Hydrophones Based on Tuning the Frequency of the Laser

A novel signal detection method for interferometric fiber optic hydrophones is described. It compensates the phase of the interferometer by tuning the frequency of the laser. The principle of this method is introduced in details. The demodulation error is analyzed and simulated theoretically. A system of data acquisition and processing is programmed, and a fiber hydrophone is tested. The average acoustic pressure sensitivity is -162.2 dB (0 dB=1 rad/μPa) over the frequency range of 20 Hz to 1.3 kHz, and the fluctuation is smaller than ±0.8 dB, which accords well with the results obtained with the method of phase generated carrier demodulation. The experimental results prove this method is feasible. This method has the advantages of no electric elements in the sensing head, the simplicity of signal processing and the wide frequency range of detection. It can be applied to all kinds of signal detection of interferometric fiber-optic sensors.