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Improving antenna near-field pattern by use of artificial impedance screens

Stanislav Maslovski·Pekka Ikonen·Constantin Simovski·Mikko Karkkainen·Sergei Tretyakov·Vasil Denchev
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Abstract

An antenna prototype utilizing artificial impedance surfaces to control the near field distribution is described. The antenna is a folded dipole placed above a finite-size artificial impedance surface. We have found that the field screening is most effective if the surface is a metal conductor. However, to achieve a reasonable value of the radiation resistance the dipole should be located far off the screen. If the surface is a magnetic wall, the antenna design is more compact, but the field behind the screen is large. Here we realize a compromise solution using an inductive surface of a moderate surface impedance, which allows realization of an effective near-field screen with still a reasonably low-profile design.

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Stanislav Maslovski, Pekka Ikonen, Constantin Simovski, Mikko Karkkainen, Sergei Tretyakov, Vasil Denchev. 2005-04-18. Improving antenna near-field pattern by use of artificial impedance screens. https://arxiv.org/abs/physics/0504123

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