摘要
讨论了应用于光纤分布式布里渊传感散射谱最优化拟合的Levenberg-Marquardt(L-M)非线性最小二乘算法。分析并推导了一种可较好地反映入纤脉冲宽度越来越窄所引起的光纤分布式布里渊传感散射谱形状变化的Pseu-do-Voigt分析拟合模型。由调制脉冲光和调制器泄漏连续光共同作用所产生的光纤分布式布里渊传感散射谱应为Lorentzian型谱和Gaussian型谱的线性权重组合。Gaussian型函数部分可视为Lorentzian型函数谱的近似修正处理。基于L-M算法对光纤布里渊传感散射谱采样数据进行了曲线拟合和最优化参数估计,所得到的结果与理论分析情况吻合。
A double linewidth Nonlinear Pseudo-Voigt analytical model of the combination between Lorentzian and Gaussian profile of Brillouin-barsd seattering spectrum is proposed to handle the spectral shape varianee caused by the short pulse interaction during the Brillouin scattering process in optical fiber distributed sensing systems. With the Levenberg-Marquardt nonlinear least .squares algorithm, some measurement data of Brillouin scattering spectrum are fitted, and some spectral parameters are optimally estimated. The results of curve fitting and optimal estimation are well in agreement with the theoretical analyses.
出处
《光学技术》
CAS
CSCD
北大核心
2009年第6期897-900,904,共5页
Optical Technique
基金
国家"863"计划资助项目(2008AA04Z406)
