基于可调谐激光器的光纤光栅波长解调系统误差分析与补偿  

The error analysis and compensation of fiber Bragg grating wavelength demodulation system based on tunable laser

作　　者：楚奇梁 刘琨[1] 江俊峰[1] 张学智[1] 郑文杰[1] 闫金玲[1] 臧传军[1] 谢仁伟[1] 刘铁根[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院,光纤传感研究所,光电信息技术教育部重点实验室,天津300072

出　　处：《光电子．激光》2018年第1期14-21,共8页Journal of Optoelectronics·Laser

基　　金：国家重大科学仪器设备开发专项(2013YQ030915)和国家自然科学基金(61475114、61378043、61405138、61505139、61227011)资助项目

摘　　要：基于可调谐激光器的光纤(Bragg)光栅(FBG)波长解调系统性能受激光器控制电路、调制参数以及光电探测器(PD)性能、弱信号采集与放大电路等诸多因素的影响,着重研究了可调谐激光器调制参数中扫描频率对光栅波长解调系统的影响,发现波长解调误差随扫描频率的不同而呈现一定的规律,对波长解调误差与激光器的扫描频率进行了拟合。将拟合结果植入解调程序中,对激光器当前扫描频率下的解调波长进行实时误差补偿,并实验验证了误差补偿后的效果。结果表明,进行误差补偿后系统最大波长解调误差比之前减小6.0倍,其中由激光器扫描频率不同导致的波长解调误差和均方差(SD)分别比补偿之前减小2.2倍和1.9倍。最终使得基于可调谐激光器的FBG波长解调系统整体波长解调误差控制在1.38pm以内,有效地满足了高速FBG系统对解调波长准确性和稳定性的要求,适用于高频动态信号的解调。The performance of fiber Bragg grating （FBG） wavelength demodulation system based on tunable laser is affected by many factors, such as the control circuit and modulation parameter of laser, performance of photodetector, acquisition and amplification circuit of weak signal. Scanning frequency is one of the most important parameters in laser modulation, and its effects on the FBG wavelength demodulation system are studied. This paper finds that the error of wavelength demodulation varies with the scanning frequency. In this paper, the error of wavelength demodulation and the scanning frequency of the laser are fitted, and the fitting results are embedded into the demodulation program to compensate the real-time error of the demodulation wavelength under the current laser scanning frequency. The effect of error compensation is verified by experiments. The results show that the maximum error of wavelength demodulation is improved by 6.0 times and the error of wavelength demodulation and standard deviation （SD） caused by laser scanning frequency are respectively reduced by 2.2 times and 1.9 times. Finally, the demodulation error of FBG wavelength demodulation system based on tunable laser is limited to 1.38 pm,which it can effectively meet the accuracy and stability of demodulation wavelength in high-speed FBG wavelength demodulation system, and can be used in the demodulation of high-frequency dynamic signal.

关 键 词：可调谐激光器 光纤Bragg光栅(FBG) 扫描频率 波长解调 误差补偿 

分 类 号：O433.1[机械工程—光学工程]