Three-component all polarization-maintaining optical fiber vector hydrophone

This paper reports a new-style all polarization maintaining optical fiber vector hydrophone which is orthogonal and unitized in three components. The signal fading caused by random phase-shift in the interferometer is eliminated by phase generated carrier (PGC) technology. The sensitivity and frequency band of the sensor is increased by optimizing the structure. Experimental results indicate that the acceleration sensitivity reaches 33dB and the fluctuation is less than 1dB over the frequency range of 20~2000Hz. The phase sensitivity is -155dB at 1000Hz. The optical vector hydrophone has an excellent directivity. The maximum asymmetric index is less than 0.4dB, while the directivity index is greater than 45dB.