构建了一套高分辨率的可复用光纤光栅波长解调系统.采用波长调谐范围为1 546 nm至1 558 nm的紧凑型可调谐半导体激光器作为光源, 来提高系统的紧凑性、波长分辨率以及响应速度, 加入标准气室作为波长基准以提高系统的长期稳定性.使用多个电极电流共同调谐的办法, 实现了在12 nm范围内半导体激光器波长分辨率高达1 pm的准连续波长扫描.利用重心算法提高光纤光栅中心波长的解调精确度和稳定性,并对解调过程进行模拟.解调系统的波长分辨率优于1 pm, 精确度接近2 pm.整个光纤布拉格光栅温度传感系统在1 550 nm附近实现了0.1℃的温度分辨率.

A compact and high-resolution multiplexed Fiber Bragg Grating (FBG) wavelength interrogation system was reported. A compact tunable Laser Diode(LD) covering wavelength from 1 546 nm to 1 558 nm is applied as the light source to improve the simplicity, wavelength resolution and the response rate of the FBG demodulation system. A standard HCN gas-cell is incorporated as the wavelength reference. The 1 pm quasi-continuous wavelength tuning of the LD over 12 nm is realized by the combination of current control on multiple electrodes. A spectral centroid algorithm is used to determine the FBG′s wavelentgth, which results in robustness of the demodulation and then the high accuracy of the FBG interrogation. The demodulation process is simulated. The experimental results show an excellent wavelength resolution of better than 1 pm and precision of about 2 pm, which corresponds to temeprature resolution of 0.1℃ around 1 550 nm in an FBG -based fiber sensor.