基于FFT和复域相关的光纤EFPI压力传感器多腔长解调方法  

Multi-cavities demodulation algorithm of EFPI pressure based on FFT and complex domain correlation

作　　者：何文涛 赵光再 宁佳晨 李金洋 史青 HE Wentao;ZHAO Guangzai;NING Jiachen;LI Jinyang;SHI Qing(Beijing Research Institute of Telemetry, Beijing 100076, China)

机构地区：[1]北京遥测技术研究所

出　　处：《遥测遥控》2019年第3期17-21,共5页Journal of Telemetry,Tracking and Command

基　　金：战略支援部队装备预先研究项目(30506020302)

摘　　要：为实现高温光纤压力传感器的温度补偿,将基于高斯拟合FFT算法与复域相关算法结合,提出一种多腔解调方法。算法首先采用基于高斯拟合的FFT算法,粗解算出各腔的大致腔长,再利用复域相关算法在小范围内解调出各个腔长的精确值。方法降低对FFT解调精度要求,并缩小相关解调算法中的虚拟腔长范围,提高解调精度和效率。最后以初始腔长为50μm、110μm和250μm进行仿真验证,算法解调精度优于10nm,证明了多腔长解调算法的有效性和准确性。A novel multi-cavities demodulation algorithm, combining the FFT and complex domain correlation, was proposed to realize the temperature compensation of EFPI based pressure sensor using in high temperature environment.Gaussian fitting based FFT was applied to demodulate cavity lengths roughly, and then complex domain correlation was used to calculate the precise lengths in more narrow ranges. This algorithm improved the demodulating precision and efficiency due to decreasing the required precision of FFT and reducing the scope of virtual cross-correlation lengths. Finally, this algorithm was verified by computer simulation with cavities of 50μm, 110μm, 250μm and the result indicate the demodulation was precise within 10 nm, which demonstrated the improved algorithm was effective and accurate.

关 键 词：多腔长解调算法 光纤EFPI压力传感器 高斯拟合 互相关 

分 类 号：TP212.1[自动化与计算机技术—检测技术与自动化装置]