密集切趾光纤光栅阵列制备及其准分布温度传感的实验研究

Fabrication and Temperature Sensing Characteristics of Dense Apodized Fiber Bragg Grating Array

针对小范围热源温度探测的需求,在线制备了密集切趾的光纤光栅阵列,采用光波长时域反射解调技术和光时域分段解调技术对切趾光栅阵列传感网络信号进行解调,实现了对小范围热源温度变化的精确测量。模拟了高斯切趾光栅的旁瓣抑制效果,结果显示高斯系数G=4时,可获得较好的谱型和较高的旁瓣抑制比。采用在线光栅阵列制备系统制备了旁瓣抑制比为20.74 dB的密集切趾光栅阵列,温度实验结果显示,传感网络的时域分段精度可达1 m,空间分辨率可达10 cm,温度灵敏度为10.15 pm/℃。该系统可应用于电缆廊道、地铁等环境下的小范围热源温度探测。

Dense apodized fiber Bragg grating arrays were on-line fabricated on a fiber drawing tower and used for temperature detection of small-scale heat sources.The signals of the grating array sensing network were demodulated through optical wavelength time domain reflection demodulation technology and optical time domain segmented demodulation technology.The sidelobe suppression effect of Gaussian apodized grating was studied and simulated.The results indicat that the gratings with good spectral type and high sidelobe compression ratio can be prepared when the Gauss coefficient G=4.A dense apodized grating array with the sidelobe compression ratio of 20.74 dB was fabricated with our grating array fabrication system.The temperature experiment results show that,for this apodized grating array sensing network,the time-domain segmentation can reach 1 m,the spatial resolution can reach 10 cm and the temperature sensitivity is 10.15 pm/℃.It is expected that the system can be applied to small-scale heat source temperature detection in cable corridors,subways and so on.