N阶色散媒质的瞬态传播特性

Transient Propagation in Nth-order Dispersive Media

本文结合Ｚ－变换对常规的时域有限差分法（ＦＤＴＤ）进行了修正，建立了一种新的Ｎ阶色散媒质瞬态特性的时域分析方法，使ＦＤＴＤ能分析和处理与频率有关的电磁场问题，具有方法简洁、易实现等优点．为验证此方法的有效性和可靠性，对Ｎ阶色散媒质的反射系数进行了分析与计算，并与解析结果进行了比较，证明了方法的正确性．同时，采用此时域方法对瞬变电磁波在Ｎ阶色散媒质中的瞬态传播特性进行了分析与讨论．

The modified FDTD method for studying the Nth-order dispersive media using Z-transforms is described in this paper.In order to demonstrate the effectiveness of this approach, the coefficient of reflection of boundary between vacuum and a 4th-order dispersive media is calculated by this FDTD method through FFT transform, and compared with the results which are obtained analytically. The transient propagation in Nib-order dispersive media and its layers is calculated and discussed.