干涉型光纤水听器移频正交解调方法  

Frequency Shift Quadrature Demodulation Method for Interferometric Fiber-Optic Hydrophone

作　　者：柯尊灵 黄文涛[1] KE Zunling;HUANG Wentao(The 23rd Research Institute,CETC,Shanghai 201900,China)

机构地区：[1]中国电子科技集团公司第二十三研究所,上海201900

出　　处：《光纤与电缆及其应用技术》2022年第4期1-5,共5页Optical Fiber & Electric Cable and Their Applications

摘　　要：干涉型光纤水听器将目标声压信号调制在激光相位上,需要进行相位解调才能恢复出目标声压信号。提出一种干涉型光纤水听器移频正交解调方法,采用移频与延时装置产生一个具有固定光频差的激光脉冲对,配合光纤水听器单元的两条干涉臂之间的特定程差,形成正交信号,同时利用干涉脉冲和参考脉冲的幅值比例关系,主要依靠简单的数学乘加运算即可实现相位解调。实测结果表明,本方法解调结果准确,抗光功率波动干扰能力强,本底噪声性能优异,可以满足光纤水听器的实际应用需求。Interferometric fiber-optic hydrophone modulates the target sound pressure signal on the phase of laser,which needs to be recovered by phase demodulation.A frequency shift quadrature demodulation method for interferometric fiber-optic hydrophone is proposed.In this method,apair of laser pulse with fixed optical frequency difference is generated by using the frequency shift and delay device.Combined with the specific path difference between the two interference arms of the fiber-optic hydrophone element,the quadrature signal is formed.At the same time,the proportional relationship of amplitude between the interference pulse and the reference pulse is used in this method.Sequentially,phase demodulation can be realized mainly by simple mathematical multiplication and addition operation.Test results show that this method has high demodulation accuracy,strong anti-interference ability of optical power fluctuation and excellent background noise performance,which can fully meet the practical application requirements of fiber-optic hydrophone.

关 键 词：干涉型光纤水听器 相位解调 移频 正交信号 

分 类 号：TN247[电子电信—物理电子学] TN763