—A method is described for the determination of the effective electromagnetic parameters of a metamaterial based only on external measurements or simulations, taking boundary effects at the interfaces between a conventional material and metamaterial into account. Plane-wave reflection and transmission coefficients at the interfaces are regarded as… (More)
—A mu-negative (MNG) metamaterial hemisphere was used to demonstrate impedance matching for a magnetic loop. The metamaterial was comprised of copper spirals deposited on an alu-mina substrate. The spirals, hemisphere, and magnetic loop were designed to operate at 450 MHz. The effect of the metamaterial hemisphere was to improve the match of the… (More)
—Several variations of a 300-MHz version of the electrically small coax-fed three-dimensional (3D) magnetic EZ antenna were designed and tested. The final version of this low-profile antenna had an electrical size that was 0 437 at 300.96 MHz. Nearly complete matching to the 50-source and high overall efficiency (nearly 100%) were achieved. The measured… (More)
—Both 300-and 570-MHz versions of an electrically small, coaxially fed Z antenna were designed and tested. These two cases demonstrate the ability to change the resonance frequency of the Z antenna by changing the value of its lumped element inductor. The numerically predicted and measured results are in good agreement.
This document reports on wireless channel measurements and models for outdoor to indoor propagation environments. Although there have been a number of publications that have recently appeared on this topic, e.g., , , and references therein, the amount of work that has been published is far less than that regarding traditional cellular… (More)