Microwave Photonics Research Laboratory, School of Electrical Engineering and Computer Science, University of Ottawa, Ontario, Canada.
Opt Lett. 2013 Jul 15;38(14):2611-3. doi: 10.1364/OL.38.002611.
We propose and experimentally demonstrate a fiber-optic sensor implemented based on a dual-frequency optoelectronic oscillator (OEO) for transverse load sensing. In the OEO loop, a phase-shifted fiber Bragg grating (PS-FBG) is employed to which a transverse load is applied to introduce a birefringence to create two orthogonally polarized notches, which leads to the generation of two oscillating frequencies. The beat frequency between the two oscillating frequencies is a function of the load force applied to the PS-FBG. The proposed sensor is experimentally demonstrated. The sensitivity and the minimal detectable load are measured to be as high as ~9.73 GHz/(N/mm) and 2.06×10(-4) N/mm, respectively. The high-frequency purity and stability of the generated microwave signal by the OEO permit extremely reliable and high-accuracy measurement. The frequency interrogation allows the system to operate at an ultra-high speed. In addition, the sensing signal is insensitive to the variations of both the environmental temperature and the optical carrier wavelength.
我们提出并实验演示了一种基于双频光电振荡器（OEO）的光纤传感器，用于横向负载传感。在 OEO 环路中，采用相移光纤布拉格光栅（PS-FBG），对其施加横向负载以引入双折射，从而产生两个正交偏振的陷波，从而产生两个振荡频率。这两个振荡频率之间的拍频是施加在 PS-FBG 上的负载力的函数。实验验证了所提出的传感器。测量得到的灵敏度和最小可检测负载分别高达~9.73 GHz/（N/mm）和 2.06×10（-4）N/mm。OEO 产生的微波信号具有很高的频率纯度和稳定性，可实现极其可靠和高精度的测量。频率询问允许系统以超高速运行。此外，传感信号对环境温度和光载波波长的变化不敏感。
