Poly-Spiral Shapes And Applications: The Celtic-Archimedean Spiral Antenna

Poly-spirals are composed of contiguously interconnected spiral elements and are ubiquitous in the monuments of various cultures since prehistoric times. In adopting poly-spiral geometries for antenna applications, we may in general choose these contiguously connected spirals to be identical or dissimilar, such as by selecting them to be of circular, eccentric, or polygonal shape. We focus on a special class of poly-spirals with circular elements, namely the Celtic-Archimedean spiral. We subsequently compare its radiation properties with those of a regular circular Archimedean of the same size and number of turns. The Celtic-Archimedean spiral could be used as a pattern and polarization diversity reconfigurable antenna due to its feeding mechanism. We compute the diversity gain provided by the Celtic-Archimedean spiral when used in a WLAN network operating at 2.4 GHz.