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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, a

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.

대표청구항 ▼

[ What is claimed is:] [1.] An antenna system including:a driven element, anda fractal counterpoise element having a portion that includes at least a first motif and a first replication of said first motif and a second replication of said first motif such that a point chosen on a geometric figure re

[ What is claimed is:] [1.] An antenna system including:a driven element, anda fractal counterpoise element having a portion that includes at least a first motif and a first replication of said first motif and a second replication of said first motif such that a point chosen on a geometric figure represented by said first motif will result in a corresponding point on said first replication and on said second replication of said first motif; wherein there exists at least one non-straight line locus connecting each said point;wherein a replication of said first motif is a change selected from a group consisting of (a) a rotation and change of scale of said first motif, (b) a linear displacement translation and a change of scale of said first motif, and (c) a rotation and a linear displacement translation and a change of scale of said first motif; andwherein said fractal counterpoise element has a perimeter compression parameter (PC) defined by:EQU PC=(full-sized antenna element length)/(fractal-reduced antenna element length)in which PC=A.multidot.log(N(D+C)). A and C are constant coefficients for said first motif, N is an iteration number, and D is a fractal dimension given by log(L)/log(r), where L and r are one-dimensional fractal counterpoise element lengths before and after fractalization, respectively.