Design of fractal slot antennas

Fractal and space-filling curves are implemented for the development of fractal slot antennas. The conventional slot is replaced by a space-filling curve having the same electrical properties. Several space-filing curves have been studied and compared. Sierpinski spacefilling curve and Minkowski fractal shape have been selected. It has been found that the antenna bandwidth is decreased with increasing the iteration number. This is mainly due to both high coupling effects between slots and width constraints imposed by higher iteration, which deteriorates the antenna matching. The 1st iteration Sierpinski slot antenna has a bandwidth of 10% and is confined in 2.2x2.2cm². The corresponding normal λ slot antenna occupies 9x0.6cm´. This shows that the proposed space-filling slot antenna has a compact shape, which allows the use of a reduced size ground plane. On the other hand, the 1st iteration Minkowski slot antenna has a bandwidth of 35% and is confined in 5x5cm², while the 2nd iteration has a bandwidth of 22.5% and is confined in 3x2cm². The design and simulation have been performed using full-wave electromagnetic simulator.