Random Effects in Planar Arrays of Thin-Wire Dipoles

Abstract

The effects of random errors in the voltage excitation of a planar array of thin-wire dipoles are analyzed. Mutuals are taken fully into account. The method of moments is applied iteratively in conjunction with a random-sampling process, to obtain mean far-field beam patterns and their expected variation, as well as several expected-gain quantities. Sinusoidal expansion and weighting functions are used. Block-Toeplitz impedance redundancies and the zeros of the excitation matrix are utilized in an efficient solution routine. Separate array analysis at fundamental and harmonic frequencies yields expected ratios of harmonic to fundamental levels. The theory is outlined and typical results of computation are presented. There is a tendency, due to mutuals, to point the beam near broadside even when the phase is completely random. Significant gain degradation is predicted at harmonic frequencies.