The objective of an antenna is to efficiently radiate or receive a signal, presumably with significant directivity and gain. That goal has always been at odds with the physical restrictions of the design, especially at HF and MF. In effect, every antenna incorporates some compromise-playing off gain with size, efficiency with bandwidth, and so on. Through the years, the exploration of these compromises has produced some useful design solutions. However, as antenna design has become a mature field, it's rare that a new approach comes to light. Here I describe a new approach that uses fractal geometry to produce very small antennas of high efficiency, with other useful attributes. Some shrunken single-element fractal antennas appear to have gain over their classic full-sized counterparts. These antennas demonstrate that a deeper investigation of electromagnetics and antennas is necessary in the context of simple and complex fractal structures and arrays. In Part 1, I'll present a practical design for very small area single-element cubical "quads," along with their comparative results.
Artículo seminal de este tipo de antenas debido a su inventor. Las antenas fractales son completamente diferentes a las antenas tradicionales: su tamaño físico es más pequeño; pueden ser multi-banda, de banda ancha o banda ultra ancha (UWB); proveer ganancias en diferentes frecuencias de forma simultánea; son muy compactas. Son una muy buena solución para las antenas en telefonía móvil y bandas de microondas y milimétricas.