Unified frequency and time-domain antenna modeling and characterization

A new methodology is presented for characterizing an antenna system in both the time and frequency domains with one set of parameters using a singularity expansion method representation. A minimal parameter set for modeling antenna systems has been demonstrated using the matrix-pencil method. It has been shown that it is possible to obtain frequency-domain patterns from pole/residue models of antenna realized effective length. Thus, a pole/residue model of the antenna realized effective length presents a complete description in both the time and frequency domains. Once such a model is available, one can obtain the antenna pattern, directivity, and gain in the frequency domain and the radiated transient waveform for an arbitrary excitation waveform and an arbitrary antenna orientation.