时域物理光学后向散射近场线积分表达式

提出了一种计算偶极子源照射时理想导体平板后向散射近场的时域物理光学（Time-Domain Physical-Optics，TDPO）线积分表达式.利用并矢分析中的面梯度定理和面散度定理，将TDPO面积分表达式化为线积分表达式.该表达式消除了积分中的奇异性，适用于偶极子天线处在任意位置处的情形.计算了导体平板和复杂目标的瞬态后向散射场，与其他方法结果吻合良好.数值结果表明，该方法在保证计算精度的前提下，可以大大提高计算效率.

Time-domain physical-optics line-integral representations of back scattered near-fields

A time-domain physical-optics (TDPO) line-integral representation is developed for the backscattered near-fields from a perfectly conducting surface illuminated by a dipole resource.The pro posed representation is derived from time-domain physical-optics(TDPO) surface-integral representation by introducing two theorems:surface gradient theorem and surface divergence theorem.The proposed representation is free from singularities for all the source/observer positions in which the dipole antenna is located.The transient backscattered magnetic fields of metal plate and a complex object are computed.The results are in good agreement with those obtained by other methods.Numerical results show that the method can not only ensure the calculation accuracy,but also greatly improve the calculation speed.