一种光纤光栅水听器灵敏度校准技术研究

为了校准光纤光栅水听器的灵敏度,开展了光纤光栅水听器灵敏度校准技术研究.本文首先介绍了光纤光栅水听器的工作原理;其次,采用可调谐激光器和带工作点控制的强度调制法,实现了光纤光栅水听器的信号解调和稳态测量;在此基础上,利用比较法建立了一种光纤光栅水听器校准系统,校准频率范围为20 Hz~10 kHz;最后,在该频率范围内对采用等效相移布喇格光栅研制的一只光纤光栅水听器的灵敏度进行了校准,对系统的测量不确定度进行了估算.结果表明,该系统可准确校准光纤光栅水听器的灵敏度,扩展不确定度为0.9 dB(k=2).

A Calibration Technique of Sensitivity of Fiber Grating Hydrophone

In order to calibrate the sensitivity of fiber grating hydrophone, a calibration technique of fiber grating hydrophone was studied. In this paper, the working principle of fiber grating hydrophone was introduced firstly. Secondly, using tunable laser and intensity modulation method with work-point controlling, the signal demodulation and stably measurement of fiber grating hydrophone was realized. Based on these methods, a calibration system of fiber grating hydrophone was established using comparison methods, and its calibration frequency range was 20 Hz to 10 kHz. Finally, using this calibration system, the sensitivity of a fiber grating hydrophone made of equivalent phase shift fiber Bragg grating was calibrated in the frequency range 20 Hz to 10 kHz, and measurement uncertainty of the system was estimated. The results proved that this system can correctly calibrate the sensitivity of fiber grating hydrophone, with its expand uncertainty (at k=2) of 0.9 dB.