Rayleigh scatter based order of magnitude increase in distributed temperature and strain sensing by simple UV exposure of optical fibre.
Rayleigh scatter based order of magnitude increase in distributed temperature and strain sensing by simple UV exposure of optical fibre.
复制标题
DOI：
10.1038/srep11177
复制
发表时间：
2015-06-16
影响因子：
4.6
通讯作者：
Kashyap R
中科院分区：
文献类型：
--
作者：
Loranger S;Gagné M;Lambin-Iezzi V;Kashyap R
我们提出了一种利用频域瑞利散射来提高信号强度从而提高分布式温度和应变传感(DTSS)灵敏度的技术。一个简单的载氢标准SMF-28光纤芯的紫外光曝光可以将瑞利背向散射光显著增强十倍，与布拉格光栅的存在无关，因此仅由紫外光曝光产生。与未曝光的用作传感元件的SMF-28光纤相比，瑞利背向散射的增加使DTSS的温度和应变分辨率提高了数量级。这种灵敏度的增强对于厘米范围或更长的传感器量规长度是有效的，低于该长度的传感器是理论上的互相关限。探测到的温升为20 MK，空间分辨率为2 cm。SMF-28的这种灵敏度增益与具有高NA的高Ge掺杂光敏光纤进行了比较。对于后者，也存在紫外线增强，尽管幅度较低，并且由于光纤固有的更高的瑞利散射信号，使得传感的噪声水平更低。
We present a technique to improve signal strength, and therefore sensitivity in distributed temperature and strain sensing (DTSS) using Frequency domain Rayleigh scatter. A simple UV exposure of a hydrogen loaded standard SMF-28 fibre core is shown to enhance the Rayleigh back-scattered light dramatically by ten-fold, independent of the presence of a Bragg grating, and is therefore created by the UV exposure alone. This increase in Rayleigh back-scatter allows an order-of-magnitude increase in temperature and strain resolution for DTSS compared to un-exposed SMF-28 fibre used as a sensing element. This enhancement in sensitivity is effective for cm range or more sensor gauge length, below which is the theoretical cross-correlation limit. The detection of a 20 mK temperature rise with a spatial resolution of 2 cm is demonstrated. This gain in sensitivity for SMF-28 is compared with a high Ge doped photosensitive fibre with a characteristically high NA. For the latter, the UV enhancement is also present although of lower amplitude, and enables an even lower noise level for sensing, due to the fibre’s intrinsically higher Rayleigh scatter signal.