用于OFDR振动传感的改进型相位生成载波算法研究

基于光频域反射（optical frequency domain reflectometry，OFDR）的振动传感技术由于其抗电磁干扰、抗腐蚀、安装方便，且具有精准的定位能力等，引起了许多的关注。而相位解调算法是OFDR振动传感的关键技术。应用于OFDR振动传感的相位解调算法有很多种，但都或多或少受调制深度或者光强大小的影响。为了同时减少这两种因素对解调结果的影响，提出了一种改进的相位生成载波算法，通过数学计算消除解调信号中的光强项和调制深度项等非线性项。分别从理论和仿真两方面与传统算法作对比，验证了改进型算法的性能，证实其可以同时减少上述两种因素对解调结果的影响。该算法可用于提高振动传感系统的稳定性。

Research on improved phase generated carrier algorithm for OFDR vibration sensing

The vibration sensing technology based on optical frequency domain reflectometry (OFDR) has attracted a lot of research due to its superior electromagnetic interference resistance, good corrosion resistance, convenient installation and accurate positioning capability. Phase demodulation algorithm is the key technology of vibration sensing based on OFDR. There are many phase demodulation algorithms applied to OFDR vibration sensing, but they are more or less affected by modulation depth or light intensity. In order to reduce the impact of these two factors on the demodulation results at the same time, this paper proposes an improved phase generation carrier algorithm, which eliminates the nonlinear terms of the light intensity term and modulation depth term in the demodulation signal through mathematical calculation. Compared with the traditional algorithm from both theoretical and simulation aspects, the performance of the improved algorithm is verified, which can reduce the impact of these two factors on the demodulation results at the same time. The work of this paper can be used to improve the stability of the vibration sensing system.