Novel electrically small spherical electric dipole antenna

This paper introduces a novel electrically small spherical meander antenna. The horizontal sections of the meander are composed of wire loops, the radii of which are chosen so that the whole structure is conformal to a sphere of radius a. To form the meander the loops are connected by wires at a meridian plane. The antenna operates as an electric dipole, i.e. it radiates the TM₁₀ spherical mode. The antenna is self-resonant and can be matched to a wide range of input feed lines without an external matching network. In this paper, a spherical meander antenna of the size ka = 0.27 and the input impedance of 72 ohms is numerically investigated and its performance is compared to that of the multiarm spherical helix antenna of the same size. Both antennas yield equal quality factors, which are about 1.5 times the Chu lower bound, but quite different cross-polarization characteristics.