Structural simplification in applications of wire antenna modelling by moment methods

Several factors which affect the efficiency of wire antenna modelling by moment methods are discussed. Structural symmetries, such as reflection symmetry in a plane, translational symmetry, and rotational symmetry, reduce the number of computations required to set up the impedance matrix, cause an N-fold reduction in matrix element evaluations, and give rise to a Toeplitz structure in the impedance matrix, respectively. Decoupling of parts of the antenna structure can result in a very limited set of moment method computations, necessary for optimization of input impedance or gain. Grouped structures with functions equivalent to a single unit can improve input impedance. The delta function excitation is used to study what transformation is needed to produce a physically measured input impedance from that computed using the delta function source model.