Application of Rooftop Functions in the Analysis of Antenna Systems
In this paper, we report the analyses of a single element antenna and array antenna using rooftop function as a basis and testing functions to model the current distribution on the antennas. The Method of Moments (MoM) was used to obtain matrix equation from the Electric Field Integral Equation (EFIE) from which the solution to the current distribution was obtained and validate using the Numerical Electromagnetic Code (NEC) software. The input impedance for dipole antenna was obtained and compared against measured results and other electromagnetic computational technique for a dipole antenna. A minimum convergence error percent of 0.03% was observed at the use of 30 rooftop functions. The single element wire antenna input impedance obtained produced better result and converged faster than the use of pulse testing technique. The antenna array characteristics simulated using the results obtained from a single dipole element, achieved the end-fire, broad-side and electronic beam steering (scanning) characteristics of linear array antenna.
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