In 1968, V.Veselego [1] hypothesized the possibility of
having simultaneous negative values for permittivity and
permeability. Thereafter he also delved into the physical
realization of –µ and –ε. Materials which display these
properties are known as metamaterial. Metamaterial are
material that have properties that are not found in nature. Over
the years Pendry et al [2] and Smith et al [3] looked at
microwave circuits with left handed transmission line
properties and microwave antenna composites with
metamaterials. In 2003 R.W Ziolkowski [4-5], designed,
fabricated and tested several metamaterial structures in the Xband. He was able to extract the material parameters with
available EM solvers. In the same year he also showed that the
power gain can be improved by making the material properties
more negative. Today, EBG structures which exhibit
metamaterial behaviour, are researched intensively in the
application of microstrip antennas. This is due to its promising
properties that allows gain enhancement [6-8], enhanced
directivity [7], relative bandwidth improvement [9] and size
miniaturization [9].
In 1968, V.Veselego [1] hypothesized the possibility ofhaving simultaneous negative values for permittivity andpermeability. Thereafter he also delved into the physicalrealization of –µ and –ε. Materials which display theseproperties are known as metamaterial. Metamaterial arematerial that have properties that are not found in nature. Overthe years Pendry et al [2] and Smith et al [3] looked atmicrowave circuits with left handed transmission lineproperties and microwave antenna composites withmetamaterials. In 2003 R.W Ziolkowski [4-5], designed,fabricated and tested several metamaterial structures in the Xband. He was able to extract the material parameters withavailable EM solvers. In the same year he also showed that thepower gain can be improved by making the material propertiesmore negative. Today, EBG structures which exhibitmetamaterial behaviour, are researched intensively in theapplication of microstrip antennas. This is due to its promisingproperties that allows gain enhancement [6-8], enhanceddirectivity [7], relative bandwidth improvement [9] and sizeminiaturization [9].
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