干涉型光纤传感器相位解调技术研究

针对干涉型光纤传感器的信号解调方法,为消除光强波动对解调结果的影响,在相位生成载波(PGC)调制解调技术的基础上,提出了一种改进型微分交叉相乘(DCM)算法。改进型DCM算法利用滤波后的两路信号进行平方相加运算,再与传统算法中的差分结果进行相除运算来实现对待测信号的解调,可消除传统算法的解调结果中与光强有关的项,从而消除光强波动的影响。仿真分析结果验证了改进型DCM算法的可行性。实验结果表明改进型DCM算法较传统算法可显著提升解调信号的抗光强波动能力。

Research on Phase Demodulation Technology of Interferometric Fiber Sensor

In order to eliminate the influence of the laser intensity fluctuation on the signal demodulation result of the interferometric fiber-optic sensor, an improved differential-cross-multiplying (DCM) algorithm is proposed based on the phase generation carrier (PGC) modulation and demodulation technology. In the improved DCM algorithm, after the square addition of the two filtered signals is performed, the square sum is used to divide the difference result in the traditional algorithm to realize the demodulation of the measured signal, which can eliminate the terms related to laser intensity in the demodulation results of the traditional algorithm, and thereby eliminate the influence of laser intensity fluctuations. The simulation analysis results verify the feasibility of the improved DCM algorithm. And an experiment is carried out with the results showing that the improved DCM algorithm can significantly improve the anti-laser intensity fluctuation ability of the demodulated signal compared with the traditional algorithm.