Efficiency of a Compact Elliptical Planar Ultra-Wideband Antenna Based on Conductive Polymers

[摘要] A planar antenna for ultra-wideband (UWB) applicationscovering the 3.1–10.6 GHz range has been designed as atest bed for efficiency measurements of antennas manufacturedusing polymer conductors. Two types of conductive polymers,PEDOT and PPy (polypyrrole), with very different thicknessesand conductivities have been selected as conductors for theradiating elements. A comparison between measured radiationpatterns of the conductive polymers and a copper referenceantenna allows to estimate the conductor losses of the twotypes of conductive polymers. For a 158 μm thick PPy polymer,an efficiency of almost 80% can be observed over the wholeUWB spectrum. For a 7 μm thick PEDOT layer, an averageefficiency of 26.6% demonstrates, considering the room forimprovement, the potential of this type of versatile materials asflexible printable alternative to conductive metallic paints. Thepaper demonstrates that, even though the PEDOT conductivityis an order of magnitude larger than that of PPy, the thickerPPy layer leads to much higher efficiency over the whole UWBfrequency range. This result highlights that high efficiency canbe achieved not only through high conductivity, but also througha sufficiently thick layer of conductive polymers.

[学科分类] 电子、光学、磁材料