Kocakarin, I. | Yegin, K.
Article | 2012 | International Journal of Antennas and Propagation2012
Surface plasmon-enhanced gold nanoantenna structures on glass substrate are studied for increased localized electric field and fluorescence at the feed gap locations of the antennas. Dipole, Archimedean balanced spiral, and bowtie and double bowtie geometries are studied for surface plasmon effect. Different flare angles for bowtie geometries are compared to each other. Double bowtie geometry with dual polarization capability exhibited superior performance with almost 56 dB field enhancement factor. We also studied the effect of substrate thickness on electric field enhancement and we found that glass thickness plays a critical role . . . for coherent addition of surface plasmons at the feed gap location. The surface plasmon effect is proven by considering perfect electric conductor model of gold instead of its modified Drude model. © 2012 Isa Kocakarin and Korkut Yegin Daha fazlası Daha az
Şişman, I. | Yegin, K.
Article | 2017 | International Journal of Antennas and Propagation2017
We propose a simple solution for jamming mitigation of L1 band GPS by electronically switching antenna beam for wide and narrow beamwidths. Assuming the jamming signal is directed from low elevation angles, antenna reception can be made significantly lower at these angles by electronically reconfiguring the antenna beamwidth. Four-element antenna array and one of the elements of the array are designated as antijam (array) mode and normal mode of the antenna. The antenna is placed on a degenerate-ground with symmetric slots in the ground. Front-end configuration for this antenna is also discussed. Simulations and measurements are per . . .formed to validate the proposed design. The antenna achieves more than 15 dB rejection in measurements and more than 20 dB cross-polarization improvement compared to standalone (normal mode) antenna. The system can easily be replaced with existing active antenna to improve antijam capability of the receiver. © 2017 İsmail Şişman and Korkut Yegin Daha fazlası Daha az
Article | 2013 | International Journal of Antennas and Propagation2013
Several nanoantennas for infrared energy harvesting applications at 30 THz are studied. Contrary to usual antenna designs, we implemented glass superstrate as opposed to glass substrate for better antenna performance. We defined a figure of merit (FOM) which includes antenna fractional bandwidth, peak gain, and half-power beamwidth of the antenna under consideration. Three different antenna structures with glass superstrate and one of them with glass substrate are studied in detail. According to our FOM definition, the Archimedean balanced spiral antenna exhibited superior performance among other structures with less sensitivity to . . .the incoming polarization of the electromagnetic wave. © 2013 Isa Kocakarin and Korkut Yegin Daha fazlası Daha az
