摘要
对于干涉型光纤水听器外调制式相位生成载波(PGC)解调方案,光干涉强度和调制深度两个参数的波动会影响解调结果。为了消除影响,本文提出利用椭圆曲线拟合以及频域搜索的参数估计方法。根据理论分析,当调制深度在[0,3.83]区间内两种方法有效,可以适应实际情况中调制深度缓慢且小范围波动的情况。为了分析验证两种方法,本文利用不同类型的待测信号进行了数值仿真,根据仿真结果,在声信号引起的相位较大的情况下,两种方法都能对参数进行正确估计;利用频域搜索的方法适用的动态范围更大;当相关参数缓慢波动时,频域搜索法能正确跟踪估计相关参数。
In PGC demodulation scheme for outer modulation of interferometric fiber hydrophone,demodulationresults can be affected by interference intensity and modulation depth.In order to eliminate the effect,parameters estimation methods base on ellipse curve fitting and frequency energy seeking are proposed.Accordingto thesis analysis,the two methods will be valid when modulation depth fluctuates between0and3.83,that meet the actual situation.Simulations are carried out based on different types of signal to be detected.According to simulation results,the two methods can estimate the parameters correctly under larger phase,thedynamic range of frequency seeking method is larger than that of ellipse fitting,and frequency seeking methodcan track the two parameters when the parameters fluctuate slowly.
作者
崔杰
刘亭亭
肖灵
CUI Jie;LIU Tingting;XIAO Ling(Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China)
出处
《应用声学》
CSCD
北大核心
2017年第5期409-416,共8页
Journal of Applied Acoustics
关键词
光纤水听器
PGC解调
光干涉强度
调制深度
参数估计
Fiber hydrophone
PGC demodulation
Interference intensity
Modulation depth
Parameters estimation
