Pre-fractal resonant rings for compact spiral antennas

This paper addresses the miniaturization of an Archimedean spiral antenna by using stacked pre-fractal metallic rings. Such rings are electromagnetically coupled to spiral antennas in order to reduce the diameter of the radiating elements. A methodology for selecting a very compact pre-fractal profile is reported. For experimental validation the fabrication of spiral antennas incorporating the selected pre-fractal rings is in progress by using flexible substrate and ink-jet printing technology.