一种简化的分析光纤布拉格光栅的时域有限差分束传输法  

A Simplified Time-domain Finite-difference Beam Propagation Method in the Analysis of Fiber Bragg Grating

作　　者：戴劲草[1] 王云明[1] 张明德[1] 孙小菡[1] 

机构地区：[1]东南大学电子工程系,江苏南京210096

出　　处：《计算物理》2005年第3期233-239,共7页Chinese Journal of Computational Physics

基　　金：江苏省高技术项目(7706008020);"十五"863项目(2002AA31230)资助项目

摘　　要：　提出了一种便于分析光纤布拉格光栅(FBG)、基于强制边界条件的简化TD FD BPM模型.采用交替隐式法(ADIM)和综合道格拉斯(GD)法,离散化时域束传输方程,获得比普通差分格式低二阶的误差。提出并采用强制边界条件,简化了光波导分析中边界处理问题.重点讨论和确定了在此条件下激励源位置、脉冲形状和径向分布函数、连续波激励条件等.在修正的正弦脉冲激励情况下,通过离散傅利叶变换,直接得到较为理想的短FBG反射谱.此法可减少数值计算时间,直观反映光脉冲传输.Under a compulsive boundary condition,a simplified time-domain finite-difference beam propagation method(TD-FD-BPM) suitable for the analysis of fiber Bragg grating(FBG) is presented.In the alternating-direction implicit method (ADIM) and the generalized Douglas(GD)scheme, the time-domain beam propagation equation is discretized with a truncation error two orders lower than that of conventional finite-difference scheme.The compulsive boundary condition simplifies the boundary model,which is important in the numerical analysis of optical waveguides with open boundary conditions.We focused on the position of excitation,the shape of the pulse and its distribution in the radial direction,and the use of the one-way continuous-wave(CW) scheme.Using a modified sinusoidal pulse,a satisfactory reflective spectrum is obtained in a short symmetrical FBG through discrete Fourier transform.

关 键 词：光纤布拉格光栅 时域 有限差 分束 径向分布函数 边界条件 傅利叶变换 光脉冲传输 传输方程 差分格式 边界处理 脉冲形状 脉冲激励 激励条件 计算时间 隐式法 离散化 激励源 光波导 连续波 反射谱 FBG 强制 二阶 正弦 理想 

分 类 号：O43[机械工程—光学工程] TN253[理学—光学]