Hilbert curve fractal antenna: A small resonant antenna for VHF/UHF applications

The usefulness of fractal Hilbert curves in antenna geometry is explored here for the first time. Apart from being simple and self-similar, these curves have the additional property of approximately filling a plane. These properties are exploited in realizing a "small" resonant antenna. This approach has resulted in an antenna size smaller than lambda /10 and still resonant, with performance comparable to a dipole whose resonant length is close to lambda /2. Numerical predictions of the input impedance of the antenna have bern compared with experiments. The effect of additional fractal iterations on the reduction of the resonant frequency has been studied. The radiation characteristics of the antenna at the resonant frequencies provided show that this is very similar to the dipole characteristics. (C) 2001 John Wiley & Sons, Inc.