Abstract
In this paper; two Ultra-Wide Band (UWB) antennas have been modeled using Singularity Expansion Method (SEM). To acquire the complex poles and the corresponding residues of the SEM model, Matrix Pencil (MP) method has been applied to the far field time response of the antennas. The poles extracted by the MP method are located precisely within the operating bands of each UWB antennas. This modeling scheme is attractive as one set of parameters are used to characterize antennas in both time and complex frequency domains. Using the basic SEM model, the transfer functions of both UWB antennas can be directly constructed.