Poly-spiral shapes and applications: the Celtic-Archimedean spiral antenna

ABSTRACT

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.

KEYWORDS:

• Poly-spiral
• Celtic-Archimedean
• MIMO
• diversity
• power combining
• reconfigurable
• broadband
• linear/circular polarization

Acknowledgements

We would like to express our gratitude to Dr. Anna Papió Toda of Apple Corporation and Dr. Enver Adas formerly Ph.D. student at UCI. They helped to fabricate the planar antenna in PCB. We also thank Ansys/Ansoft Corporation for the simulation tool HFSS which has been very useful and convenient for antenna simulation. Finally, we would like to acknowledge Rogers Corporation for the use of their low loss substrate sample for the antenna fabrication.

Disclosure statement

No potential conflict of interest was reported by the author(s).