Abstract A compact optical fiber sensor by embedding fiber Bragg gratings (FBGs) in strongly coupled multicore fiber (SCMCF) is proposed for multipoint and multiparameter sensing. To build the device, two FBGs with different peak wavelengths were inscribed in a segment of SCMCF. Then one end of the SCMCF was fusion spliced to a single-mode fiber (SMF) and the other end of the SCMCF was cleaved. In the SMF-SCMCF structure, two supermodes are excited, as a result, the reflection spectrum exhibits a sinusoidal pattern with two sharp peaks. The wavelength position of the FBGs and the supermode coupler can be extracted simultaneously. Two distinct FBGs inscribed in different positions of the SCMCF were used to demonstrate quasi-distributed multipoint sensing in the proposed structure. To the best of our knowledge, this is the first demonstration of an optical fiber sensor that combines FBGs with SCMCF. The sensor here proposed has the advantage of compact size, low-cost, good mechanical strength and ease of interrogation.

中文翻译：

---

用于多点和多参数传感的带有 FBG 的强耦合多芯光纤

摘要 提出了一种将光纤布拉格光栅（FBG）嵌入强耦合多芯光纤（SCMCF）中的紧凑型光纤传感器，用于多点和多参数传感。为了构建该设备，将具有不同峰值波长的两个 FBG 刻在 SCMCF 的一段中。然后将 SCMCF 的一端熔接至单模光纤 (SMF)，并将 SCMCF 的另一端切割。在 SMF-SCMCF 结构中，两个超模被激发，因此反射光谱呈现出具有两个尖峰的正弦图案。FBG 和超模耦合器的波长位置可以同时提取。刻在 SCMCF 不同位置的两个不同的 FBG 用于演示所提出结构中的准分布式多点传感。据我们所知，这是将 FBG 与 SCMCF 相结合的光纤传感器的首次演示。这里提出的传感器具有体积小、成本低、机械强度好和易于查询的优点。