| 摘要 |
An antenna system includes a ground counterpoise or a top-hat located load assembly having at least one element whose physical shape is at least partially defined as a first or higher iteration deterministic fractal. The resultant ground counterpoise may rely upon an opening angle for performance, and produces a more compact antenna system relative to prior art non-Euclidean ground counterpoise elements. A vertical antenna system may be fabricated with fractal ground elements and a vertical element that may also be a fractal. Gain characteristics of antenna systems utilizing a fractal ground counterpoise are no worse than prior art, larger, systems, and exhibit improved vertical polarization characteristics, and a termination impedance of about 30 OMEGA . A vertical antenna system preferably includes vertically spaced-apart fractal conductive and passive elements, and one or more fractal ground elements. The resultant antenna system may be tuned by rotating the vertical elements relative to each other, and/or by varying the spaced-apart distance therebetween. Fractalized ground counterpoise elements may be fabricated on a flexible printed circuit substrate, and/or placed within the support mount of a cellular telephone car antenna. A vertical antenna having a fractalized top-hat loading assembly advantageously reduces resonant frequency, size and area of the loading assembly, without substantial penalty in performance.
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