基于快速傅里叶变换和能量重心联合算法的法布里-珀罗腔长解调方法

Demodulation Method of Fabry-Perot Sensor Based on FFT Algorithm Associated with Energy Centrobaric Correction Method

在基于快速傅里叶变换的光纤法布里-珀罗传感器解调方法的理论分析基础上,引入了离散频谱能量重心校正方法,改进了FFT算法。仿真结果表明该联合算法解调值与真实值一致性较好。并通过实验加载0~10 Mpa的油压,对压力和解调得到的传感器腔长数据进行拟合,并将拟合得到的曲线与参考值比较,相对误差为0.003%。实验结果表明,FFT与能量重心联合解调方法可以得到较高的精度。

In this paper, the fast Fourier transform （FFT） demodulation method for Fabry-Perot sensors is theoretically ana- lyzed and a kind of energy centrobaric correction method for discrete spectrum is proposed to improve the precision of tradi- tional FFT demodulation method. In the simulation, the demodulation results match the real length of the Fabry-Perot cavity very well. In the experiment, the cavity is varied by oil pressure ranging from 0 to 10 Mpa. By fitting the curves of demodu- lation results with that of reference value, the relative error is 0. 003%. Experiments show that this new method serves the purpose of high resolution demodulation for Fabry-Perot sensors.