Design of a balanced ball antenna using a spherical helix wound over a full sphere

This paper considers the design and build of a balanced thin wire ball and antenna suitable for on-body applications when worn as an accessory such as a free hanging toggle or pompom. A novel structure that consists of a dipole, fed with shielded wire with the linear sections extended by two spiral arms of thin wire wound onto a ball of low dielectric material. The target frequency is 2.45 GHz. Good bandwidth, good gain and axial ratio are achieved via simulation. Results using a multi-grid formulation of the time-domain Transmission-Line Matrix (TLM) method (CST) validated using NEC are presented.