Broadband circularly-polarised Spidron fractal slot antenna

Abstract

A broadband circularly-polarised fractal antenna is proposed, designed, and tested. The concept of a novel Spidron fractal system is employed to achieve both broadband and circular-polarisation characteristics. Presented is the first known application of a Spidron fractal to antenna design. A simple 50 Ω microstrip line is used to excite the Spidron-shaped slot. The total dimensions of the fabricated antenna are 40×40×1.52 mm3. The measured −10 dB return loss bandwidth and the 3 dB axial ratio bandwidth are 78.3 and 15.2%, respectively. The peak gain of the antenna is 4.3 dBi.