Folded dipoles of two or more elements

The impedance transformation of a multi-element folded dipole depends on the ratios of the diameters and spacing of the elements constituting the folded dipole proper. Formulae for the impedance transformation of two-element folded dipoles, of symmetrical three- and four-element dipoles and of general three-element dipoles are given. Based on these equations, nomograms are presented to facilitate the design of two- and three-element folded dipoles.