Study of Equivalent Edge Currents in Geometrical

等效边流法以最小的计算复杂度扩展了几何绕射理论的适用范围。场用称为等效边缘电流（EECg）的虚拟线电流的线积分表示。MEC的准确性在很大程度上取决于EECs表达的质量。这项工作给出了两个新的概念和方法来定义一般的边缘点的EEC。“使用相位变化最快的路径的EEC”成功地消除了所有的假奇异点。本文提出了基于广义费马原理的修正边缘表示法，并成功地用经典的Keller衍射系数定义了精确的等效光学系数。得到了如下结果：数值检验了MER的有效性。它几乎与UTD具有相同的潜力，UTD以其最高的精度而闻名。MER应用于PO组件时，在减少表面到线积分减少方面提供了完美的数值精度。MER应用于边缘波分量时，会导致错误的结果。提出了一种简单的校正方法，省去了菲涅耳积分等特殊函数，采用时间选通技术提取低阶衍射波由于无回声室中的残余反射而失败，首次在PO中发现了穿透光线。这条射线存在于具有曲率的表面中。已经开始了根据EEC的衍射场的可视化，并演示了虚拟穿透射线

The method of equivalent edge ourrents (MEC) extends the applicability of geometrical theory of diffraction (GTD) with the minimum complexity. Fields are expressed in terms of line integration of fictitious line currents called equivalent edge currents (EECg). The accuracy of MEC is greatly dependent upon the quality of expressions of EECs. This work gives two novel concepts and methods for defining EECs for general edge points. "EECs using paths of most rapid phase variation" succeeds in eliminating all the false singularities. "Modified edge representation (MER)" based upon generalized Fermat's principle are proposed and succeeds in defining accurate EECs with only the classical Keller's diffraction coefficients. Following results are obtained.The validity of MER is numerically checked. It has almost the same potential as the UTD, which is known for the highest accuracyMER, as applied to the PO components, gives numerically perfect accuracy in reducing the surface to line integral reduction. MER, as applied to the fringe wave components, causes erroneous results. Simple correction method is proposed, which dispense with special functions such as Fresnel integralsExtraction of lower order diffracted waves by adopting the time gating technique was not successful due to residual reflection in unechoic chamberFictitious penetrating rays in PO is found for the first time. This ray exist in the surface with the curvatureVisualization of diffracted fields in terms of EECs has started and fictitious penetrating rays are demonstrated