2015 31st International Review of Progress in Applied Computational Electromagnetics (ACES), 2015
A passive, low-profile multi-resonant Planar-Inverted-F Antenna (PIFA) element well-suited for po... more A passive, low-profile multi-resonant Planar-Inverted-F Antenna (PIFA) element well-suited for portable communications is presented. The antenna combines the optimal low-profile geometry of a planar inverted-F antenna with a double-tuned structure to create a multi-resonant element with monopole-class radiation properties. The form factor and overall dimensions are held constant for comparisons to a similar single-resonant antenna in different near-field environments.
Uludağ University Journal of The Faculty of Engineering, 2011
A two-dimensional FDTD-based subsurface imaging virtual tool is introduced. The Ground Penetratin... more A two-dimensional FDTD-based subsurface imaging virtual tool is introduced. The Ground Penetrating Radar (GPR) virtual tool can be used to generate synthetic scattering data for various subsurface scenarios. The virtual tool may be used for both educational and research purposes. Effects of different transmit/receive antenna configurations/locations, signal waveforms, scan alternatives, etc., may all be investigated. Signal and/or image processing groups can test different imaging algorithms on the scattering data generated via GrGPR and do performance analyses.
─ Analysis of the structure of the level sets of transducer power gain and voltage gain of a two-... more ─ Analysis of the structure of the level sets of transducer power gain and voltage gain of a two-port network enables a semi-analytical method for finding the extrema these performance indicators as the port terminations vary in bounded rectangles in the complex plane. In particular, we show that the extrema are necessarily attained in small-dimensional subsets of the given rectangles. This provides efficient means to assess the impact of variability in the port terminations numerically. As an example, we study how variability in the port terminations affects the performance of a biotelemetry system composed of magnetically coupled small loops with highly sensitive impedance matching properties. Index Terms ─ Sensitivity analysis, tolerance analysis, transducer power gain, two-port networks, voltage gain.
─ In this paper, a new perfect magnetic conductor (PMC) substrate for improving the directivity o... more ─ In this paper, a new perfect magnetic conductor (PMC) substrate for improving the directivity of patch and dipole antennas is introduced. We used biased grounded ferrite to construct this new substrate. The most important difference between this substrate and the other artificial magnetic conductor (AMC) structures is the homogeneity. A conventional electromagnetic AMC has a periodic nature and as a result it is not homogenous but this novel substrate is homogenous. The results show that the directivity of both the patch and the dipole antennas is improved surprisingly in the presence of this novel homogenous PMC substrate. The physical reasons for the improvements are also given. Moreover, at the last section, we have calculated the magnetic loss of this magnetic anisotropic substrate. Index Terms ─ Biased-grounded ferrite, dipole antenna, directivity, Faraday rotation, magnetic loss, patch antenna.
2015 31st International Review of Progress in Applied Computational Electromagnetics (ACES), 2015
A passive, low-profile multi-resonant Planar-Inverted-F Antenna (PIFA) element well-suited for po... more A passive, low-profile multi-resonant Planar-Inverted-F Antenna (PIFA) element well-suited for portable communications is presented. The antenna combines the optimal low-profile geometry of a planar inverted-F antenna with a double-tuned structure to create a multi-resonant element with monopole-class radiation properties. The form factor and overall dimensions are held constant for comparisons to a similar single-resonant antenna in different near-field environments.
Uludağ University Journal of The Faculty of Engineering, 2011
A two-dimensional FDTD-based subsurface imaging virtual tool is introduced. The Ground Penetratin... more A two-dimensional FDTD-based subsurface imaging virtual tool is introduced. The Ground Penetrating Radar (GPR) virtual tool can be used to generate synthetic scattering data for various subsurface scenarios. The virtual tool may be used for both educational and research purposes. Effects of different transmit/receive antenna configurations/locations, signal waveforms, scan alternatives, etc., may all be investigated. Signal and/or image processing groups can test different imaging algorithms on the scattering data generated via GrGPR and do performance analyses.
─ Analysis of the structure of the level sets of transducer power gain and voltage gain of a two-... more ─ Analysis of the structure of the level sets of transducer power gain and voltage gain of a two-port network enables a semi-analytical method for finding the extrema these performance indicators as the port terminations vary in bounded rectangles in the complex plane. In particular, we show that the extrema are necessarily attained in small-dimensional subsets of the given rectangles. This provides efficient means to assess the impact of variability in the port terminations numerically. As an example, we study how variability in the port terminations affects the performance of a biotelemetry system composed of magnetically coupled small loops with highly sensitive impedance matching properties. Index Terms ─ Sensitivity analysis, tolerance analysis, transducer power gain, two-port networks, voltage gain.
─ In this paper, a new perfect magnetic conductor (PMC) substrate for improving the directivity o... more ─ In this paper, a new perfect magnetic conductor (PMC) substrate for improving the directivity of patch and dipole antennas is introduced. We used biased grounded ferrite to construct this new substrate. The most important difference between this substrate and the other artificial magnetic conductor (AMC) structures is the homogeneity. A conventional electromagnetic AMC has a periodic nature and as a result it is not homogenous but this novel substrate is homogenous. The results show that the directivity of both the patch and the dipole antennas is improved surprisingly in the presence of this novel homogenous PMC substrate. The physical reasons for the improvements are also given. Moreover, at the last section, we have calculated the magnetic loss of this magnetic anisotropic substrate. Index Terms ─ Biased-grounded ferrite, dipole antenna, directivity, Faraday rotation, magnetic loss, patch antenna.
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