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arXiv · 1712.02613

The Radiation Efficiency Cost of Resonance Tuning

L. Jelinek·K. Schab·M. Capek
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Abstract

Existing optimization methods are used to calculate the upper-bounds on radiation efficiency with and without the constraint on self-resonance. These bounds are used for the design and assessment of small electric-dipole-type antennas. We demonstrate that the assumption of lossless, lumped, external tuning skews the true nature of radiation efficiency bounds when practical material characteristics are used in the tuning network. A major result is that, when realistic (e.g., finite conductivity) materials are used, small antenna systems exhibit dissipation factors which scale as $(ka)^{-4}$, rather than $(ka)^{-2}$ as previously predicted under the assumption of lossless external tuning.

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BibTeXRIS

L. Jelinek, K. Schab, M. Capek. 2017-11-15. The Radiation Efficiency Cost of Resonance Tuning. https://doi.org/10.1109/tap.2018.2870492

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