The Near Fields of Linear and Planar Arrays of Dipoles -- On- and Off-Axis

Abstract

The near fields of arrays of Hertzian and halfwave dipoles are analyzed on and about the perpendicular axis of symmetry of the arrays. Arrays were developed from single short or long dipoles, first single-dimensionally, then two-dimensionally, and the electric and magnetic fields and the Poynting vector were computed and plotted. The effects of dipole spacing and array dimensions are individually addressed. Oscillations appear in the field and Poynting vectors of multidipole arrays in the near field region, and there are no reductions in field intensities out to distances of several tens of wavelengths for a 10λ × 10λ square array.