Fractal antenna engineering: the theory and design of fractal antenna arrays

Abstract

A fractal is a recursively generated object having a fractional dimension. Many objects, including antennas, can be designed using the recursive nature of a fractal. In this article, we provide a comprehensive overview of recent developments in the field of fractal antenna engineering, with particular emphasis placed on the theory and design of fractal arrays. We introduce some important properties of fractal arrays, including the frequency-independent multi-band characteristics, schemes for realizing low-sidelobe designs, systematic approaches to thinning, and the ability to develop rapid beam-forming algorithms by exploiting the recursive nature of fractals. These arrays have fractional dimensions that are found from the generating subarray used to recursively create the fractal array. Our research is in its infancy, but the results so far are intriguing, and may have future practical applications.

Design of a Novel Super Wide Band Circular-Hexagonal Fractal Antenna

“…Self similarity and space filling are two common important properties of fractal geometry. Self similarity leads to wide band while space filling increases the electrical length [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39]. In [26], a super wide band fractal antenna had been modeled and simulated for super wideband application.…”

Novel Fractal Antenna Arrays for Satellite Networks: Circular Ring Sierpinski Carpet Arrays Optimized by Genetic Algorithms

“…The Sierpinski rectangular carpet and triangular gasket have been efficiently used in the past for the realization of antenna arrays with specific operational features [1,2,31]. Both of these types, although can produce arrays with high directivity and potentially low sidelobes, cannot give radiation patterns with azimuthal uniformity.…”

“…The fractal antenna elements, the majority of them being printed configurations, have compact size, low profile and cost, multi-band operation, easy feeding and, potentially, optimized operation by suitable modification [4][5][6][7][8][9]. On the other hand, the application of the fractal technique to the design of an antenna array can produce radiating systems of large size, and as a consequence of high gain, frequency-independent or multi-band characteristics and radiation patterns with low side-lobe level [1][2][3]10]. Moreover, they can be fed one by one, thus operating as Direct Radiating Antennas (DRAs) and can function as phased arrays without the disadvantages of the classical systems of Focal Array Fed Reflectors (FAFRs) used in the past.…”

“…The fractal antenna engineering research is focused on two basic areas: the first deals with the analysis and design of fractal radiating elements, and the second concern the application of the fractal theory and the design of antenna arrays [1][2][3]. Both antenna types have attributes highly desirable in military as well as in commercial sectors.…”

Multiband Fractal Planar Inverted F Antenna (F-Pifa) for Mobile Phone Application

“…The Planar inverted-F antenna (PIFA) is currently being used as an embedded antenna in many radiotelephone handsets [2][3][4][5][6][7][8][9][10]. It is one of the most promising antenna types because it is small and has a low profile, making it suitable for mounting on portable equipment.…”