—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)
—Multipath propagation environment effects, such as frequency-selective fading, have a strong impact on the quality of a wireless channel. For example, multipath can impact bit error rate (BER) differently from Gaussian noise. For testing wireless devices/systems in these multipath environments it is imperative to have a reliable, controllable, and… (More)
Certain commercial entities, equipment, or materials may be identified in this document in order to describe an experimental procedure or concept adequately. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the entities, materials, or equipment are necessarily the… (More)
—In this paper, a study is made of the electrostatic potential and field of an electric dipole located in the interface between two dielectric regions. When the dipole is oriented perpendicular to the interface, the detailed position of the charges of the dipole relative to the location of the interface has a significant effect on the value of the field… (More)
—In this paper, we present the extraction for effective material parameters for a metamaterial from TE or TM waveguide measurements with generalized sheet transition conditions (GSTCs) used to provide electric and magnetic surface susceptibilities that approximate boundary effects between the metamaterial and air. The retrieval algorithm determines the… (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.