Evaluation of the Input Impedance and Impedance Quality Factor of a Dipole in Spatial and Spectral Domains

Abstract

In classic antenna analysis, there exist several methods of calculating input impedance when the source distribution of an antenna is known. The well-known induced EMF method, based on spatially distributed currents, is typically applied for this purpose and, thereby, serves as a reference for this research. Conversely, the spectral domain method takes the opposite approach for the input impedance and is evaluated using a far-field pattern. This paper compares the induced EMF method and the spectral domain method. Furthermore, the quality factor of the dipole antenna, based on the impedance variation with frequency, is calculated for both methods. This study shows that the induced EMF method and the spectral domain method are in close agreement.