长周期光纤光栅耦合特性及模拟分析

The Analysis and Simulation on the Mode coupling Characteristics of Long period Fiber Grating

本文采用简化的三层光纤模型 ,分析长周期光纤光栅的耦合特性 ,着重对包层模场分布及其与纤芯基模的耦合系数进行研究 ,运用计算机软件包Matlab进行建模计算 ,得出纤芯基模和一阶低次包层模的场、能量分布及其相互耦合规律 .分析中应用了图解法和简化计算的方法 ,数值计算结果表明纤芯基模与一阶低次奇模的耦合要比其与一阶低次偶模的耦合强得多 .该特征 (耦合特性和图表 )

This paper mainly presents the analysis and simulation on the mode coupling characteristic of long period fiber grating,focusing on the research of cladding mode field distribution and coupling coefficients.With the aid of simplified three layered model,we use Matlab to simulate the results,and get the cladding mode field and intensity distribution.The numerical results make it clear that the coupling between the core mode and the first rank odd order cladding modes is much stronger than the coupling between the core mode and the first rank even order cladding modes.We use the graphical method and the simplified calculation to get the result,which can be compared with oversea publications.