A THIN DIPOLE ANTENNA DEMONSTRATION OF THE ANTENNA MODELING CAPABILITIES OF THE FINITE DIFFERENCE TIME DOMAIN TECHNIQUE

Abstract

The Finite Difference Time Domain (FDTD) technique has been successfully applied for modeling the electromagnetic scattering from and coupling into a variety of objects. In this communication we use FDTD to compute the input impedance of a thin dipole antenna. The short circuit current and open circuit voltage at the antenna terminals are computed over a wide bandwidth using pulsed plane wave excitation, then Fourier transformed to the frequency domain and divided to obtain the complex input impedance over a wide bandwidth using one FDTD computation. These results are compared with thin wire antenna results using the Method of Moments and good agreement is obtained except at very low frequencies, where the FDTD results obtained using this approach lose accuracy due to the imperfect outer absorbing boundary. [Vol. 5, No. 1, pp. 2-18 (l990)]