Abstract: The round contour integration method is proposed to accurately simulate the currents on conducting thin-wire by using the subsell technique in the Finite Difference Time Domain (FDTD) method. Through calculating the characteristic impedance of coax, the scattering current in a conducting thin-wire for E type plane wave incidence and the input admittance of cylindrical monopole antenna, it is testified that the proposed method is more accurate than the conventional square contour integration method.

Key words: FDTD method, subcell technique, round contour integration method, conducting thin-wire

摘要： 提出了在时域有限差分（FDTD）方法中应用亚网格技术精确模拟细导线上电流的改进方法——圆形积分回路法。通过计算同轴线特性阻抗、无限长细导线对 E 型平面波的散射电流以及单极细圆柱形天线的输入导纳，对所提出的方法作了验证，证明了该方法比常用的矩形积分回路法对细导线上电流的模拟要精确得多。

关键词: 时域有限差分法, 亚网格技术, 圆形积分回路法, 细导线