时域有限差分(FDTD)方法由于其强大的功能,已经成为电磁场数值模拟的重要方法之一,本文主要讨论了时域有限差分法对微波源电路建模的理论和方法:模拟子电路的SPICE软件结合FDTD法的建模方法。根据传统的FDTD加入集总元件的建模方法的不足,提出用SPICE软件结合FDTD法进行包含集总元件的微波电路的建模,通过此种方法可以方便的对任意端口数、任意复杂度的微波子电路进行建模。 Because of its powerful function, the FDTD method has become one of the most important methods for the numerical simulation of electromagnetic fields. This paper mainly discusses the theory and method of modeling the microwave source circuits by the finite-difference time-domain method: Software combined with FDTD modeling method. According to the shortcomings of the traditional FDTD adding lumped element modeling method, the modeling of microwave circuit including lumped elements by using SPICE software combined with FDTD method is proposed. By this method, the number of arbitrary ports, any complexity Microwave sub-circuit modeling.