光学与光电技术, 2017, 15 (5): 54, 网络出版: 2017-11-07
DFB激光器传感信号干涉仪解调技术研究
Research on Demodulation Technology of DFB Laser Sensor signal by interferometer
DFB激光器 传感器 Mach-Zehnder干涉仪 3×3耦合器 偏振光 DFB laser sensor Mach-Zehnder interferometer 3×3 coupler polarized light
摘要
提出了一种以基于3×3耦合器的非平衡光纤Mach-Zehnder干涉仪为核心元件解调DFB传感信号的技术方案。运用光波导和偏振光理论,推导出干涉仪输出光强表达式,分析了干涉仪输入光偏振态对可见度以及相位噪声的影响;利用三路输出信号之间互存120°相位差这一特点,提出了一种解调算法。分析发现,该方案在干涉仪可见度不为0的前提下,能够克服可见度变化对干涉仪输出的影响,获得传感信号的线性输出。
Abstract
A technical proposal of demodulating DFB laser sensor signal was put forward. 3×3 coupler unbalanced Mach-Zehnder interferometer was used as core element of the proposal. The expression of interferometer’s output light intensity was got by using waveguide and polarized light theory. The impact of input light polarization on visibility and phase was analyzed. A demodulation algorithm was proposed of 120 degree phase difference between three output signals. While the visibility is not zero, this proposal could overcome the impact of visibility on the output of the interferometer, and the linear sensor signal output could be got.
李东, 曾文锋, 刘诗尧, 田玉敏, 谭威, 易志刚. DFB激光器传感信号干涉仪解调技术研究[J]. 光学与光电技术, 2017, 15(5): 54. LI Dong, ZENG Wen-feng, LIU Shi-yao, TIAN Yu-min, TAN Wei, YI Zhi-gang. Research on Demodulation Technology of DFB Laser Sensor signal by interferometer[J]. OPTICS & OPTOELECTRONIC TECHNOLOGY, 2017, 15(5): 54.