Circularly polarized fractal slot antenna

Abstract

A circularly polarized fractal slot antenna is proposed in this paper. The design is based on the Sierpinski shape. The conductors and nonconductors configurations have been exchanged to produce a Sierpinski slot antenna configuration. Then, four versions of the developed Sierpinski slot antenna are placed at right angles to each other to form a symmetrical structure in the form of square. In addition, by introducing an asymmetry in the proposed slot antenna, which is implemented by extending the ground into the square antenna, circular polarization is achieved. The proposed slot antenna has a 3 dB axial ratio bandwidth of 28% (8.6 to 11.4 GHz) with VSWR < 2. The antenna has a maximum gain of 5 dB, radiation efficiency of 97%, and a compact size of 2/spl times/2 cm/sup 2/. The analysis and design of the proposed antenna have been performed using the full-wave electromagnetic simulator HFSS/spl reg/. The proposed antenna has been fabricated and measured, where good agreement between simulated and measured results is observed.