Diffraction Amplitudes from Periodic Neumann Surface: Low Grazing Limit of Incidence (II)
Diffraction Amplitudes from Periodic Neumann Surface: Low Grazing Limit of Incidence (II)
复制标题
周期性诺伊曼表面的衍射振幅：低掠射极限 (II)
DOI：
10.1093/ietele/e89-c.9.1362
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Y. Tamura
中科院分区：
文献类型：
--
作者：
J. Nakayama;K. Hattori;Y. Tamura
本文研究了低掠入射时横磁(TM)波通过理想导电三角形周期表面的奇异行为。表面最大偏移量以上的波场被表示为具有修正的衍射幅度的Floquet模的总和，而三角形凹槽内的波场被写为具有未知模幅的导模的总和。在此基础上，推导出了两组关于这种振幅的方程。从方程组出发，分析表明，在入射的低掠入射极限下，所有的振幅都消失了。根据这一事实，解析地得出结论：对于任意周期长度和任意三角形高度，在入射的低掠入射极限下，不发生绕射，仅发生反射。数值算例验证了这一理论结果。
This paper deals with the singular behavior of the diffraction of transverse magnetic (TM) waves by a perfectly conductive triangular periodic surface at a low grazing limit of incidence. The wave field above the highest excursion of the surface is represented as a sum of Floquet modes with modified diffraction amplitudes, whereas the wave field inside a triangular groove is written as a sum of guided modes with unknown mode amplitudes. Then, two sets of equations are derived for such amplitudes. From the equation sets, all the amplitudes are analytically shown to vanish at a low grazing limit of incidence. From this fact, it is concluded analytically that no diffraction takes place and only reflection occurs at a low grazing limit of incidence for any period length and any triangle height. This theoretical result is verified by a numerical example.