摘要
吸收边界条件的选取在使用时域有限差分法分析设计衍射光学元件的过程中有着举足轻重的作用。文章从麦克斯韦方程组出发,推导出了一维吸收边界条件的解析解及该吸收边界对TEM波的反射系数,用数值模拟验证了在激励源分别处于讨论区域右边、中间,且在TEM波传播的同时一直存在的情况下,一维Mur一阶吸收边界条件和波延迟法的优质吸收效果。对两种边界条件的计算误差进行了对比和分析,结果表明Neum ann边界条件波形稳定早,数值精度高,Mur一阶边界条件波形稳定稍迟,有一定误差,但吸收效果很好。
Choosing appropriate absorbing boundary holds the balance in analyzing the effects of optical elements on travelling light - wave based on Finite - Difference Time - Domain Method. Beginning from the Maxwell equations, analytical solution of one - dimen- sional absorbing boundary condition and its reflection coefficients are deduced in this article, perfect absorbing effect of first order Mur absorbing boundary and travelling - wave time - delay method are proved through computational simulation on the condition that the excitation source at the right truncation boundary or at the middle of discussed region exists as long as the time of TEM wave＇s propagation, and computation errors are also analyzed. It is proved that light - wave is stabilized early and has higher numerical precision un- der the Neumann boundary condition than Murl boundary condition. Both the Neumann and Murl conditions have excellent absorption character to TEM light - wave.
出处
《南昌航空大学学报（自然科学版）》
CAS
2010年第1期8-14,20,共8页
Journal of Nanchang Hangkong University(Natural Sciences)
基金
南昌航空大学科研基金项目"空间坐标调制达曼光栅的最优化设计方法研究"(EC200908228)
关键词
时域有限差分
吸收边界
TEM波
激励源
finite - difference time - domain
absorbing boundary
TEM wave
excitation source
