Lumped-Network FDTD Method for Simulating Transient Responses of RF Amplifiers Excited by Intentional Electromagnetic Interference Signals

Unintentional as well as intentional electromagnetic interference can cause interference and performance degradation of microwave circuits or systems. In this article, a modified multiport lumped-network finite-difference time-domain method (FDTD) method based on Y-matrix is proposed, where bilinear transform is used to incorporate the
V–I
relation of the lumped-network into FDTD iteration. It is further used for simulating transient responses of
mesfet
-based amplifiers, which are often used in many radar and communication systems. The excitation of such an RF amplifier is assumed to be an intentional electromagnetic interference (IEMI) signal but with different waveforms and magnitudes. Parametric studies are performed to show hybrid effects of waveforms and magnitudes of the IEMI signals on the transient coupled voltages at the output port of such
mesfet
-based amplifier, with useful information obtained for understanding the interaction process between the intentional electromagnetic interference signals and active components.