The Experts below are selected from a list of 1548 Experts worldwide ranked by ideXlab platform

Altintas A. - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of thin dielectric cylindrical reflector having an arbitrary Conic Section profile illuminated by complex line source: H-polarization case
    'Institute of Electrical and Electronics Engineers (IEEE)', 2014
    Co-Authors: Oguzer T., Kuyucuoglu F., Altintas A.
    Abstract:

    Arbitrary Conic Section profile and thin dielectric reflector is analyzed by using the Method of Analytical Regularization (MAR) technique based on Riemann-Hilbert problem and Fourier inversion procedures. The reflector surface is assumed to be illuminated by an H-polarized complex line source type feed antenna. The convergence of the solution is verified and some changes in the radiation patterns are obtained especially for rather thicker cases. © 2014 IEEE

  • Analysis of an arbitrary-profile, cylindrical, impedance reflector surface illuminated by an E-polarized complex line source beam
    'Informa UK Limited', 2014
    Co-Authors: Kuyucuoglu F., Oǧuzer T., Altintas A.
    Abstract:

    Electromagnetic scattering from a cylindrical reflector surface having an arbitrary Conic Section profile is studied. We assumed an electrically thin layer antenna illuminated by a complex line source in E-polarization mode. Our boundary value formulation, without loss of generality, involves an integral equation approach having impedance-type thin-layer boundary conditions. For simplicity, we also considered both faces of the reflector of the same uniform impedance value. Our computation employs the Method of Analytical Regularization (MAR) technique: the integral equations are converted into the discrete Fourier transform domain yielding two coupled dual series equations, which are then solved by the Fourier inversion and Riemann Hilbert Problem techniques. We demonstrate the accuracy and the convergence behaviors of our numerically solved MAR results that can serve as an accurate benchmark for comparison with widely used results obtained by approximate boundary conditions. © 2013 Taylor and Francis

  • Analysis of an arbitrary-profile, cylindrical, impedance reflector surface illuminated by an E-polarized complex line source beam
    'Informa UK Limited', 2014
    Co-Authors: Kuyucuoglu F., Oguzer T., Altintas A.
    Abstract:

    Cataloged from PDF version of article.Electromagnetic scattering from a cylindrical reflector surface having an arbitrary Conic Section profile is studied. We assumed an electrically thin layer antenna illuminated by a complex line source in E-polarization mode. Our boundary value formulation, without loss of generality, involves an integral equation approach having impedance-type thin-layer boundary conditions. For simplicity, we also considered both faces of the reflector of the same uniform impedance value. Our computation employs the Method of Analytical Regularization (MAR) technique: the integral equations are converted into the discrete Fourier transform domain yielding two coupled dual series equations, which are then solved by the Fourier inversion and Riemann Hilbert Problem techniques. We demonstrate the accuracy and the convergence behaviors of our numerically solved MAR results that can serve as an accurate benchmark for comparison with widely used results obtained by approximate boundary conditions

Ayhan Altintas - One of the best experts on this subject based on the ideXlab platform.

  • analysis of an arbitrary Conic Section profile cylindrical reflector antenna h polarization case
    IEEE Transactions on Antennas and Propagation, 2004
    Co-Authors: Taner Oguzer, A I Nosich, Ayhan Altintas
    Abstract:

    Two-dimensional scattering of waves by a perfectly electric conducting reflector having arbitrary smooth profile is studied in the H-polarization case. This is done by reducing the mixed-potential integral equation to the dual-series equations and carrying out analytical regularization. To simulate a realistic primary feed, directive incident field is taken as a complex source point beam. The proposed algorithm shows convergence and efficiency. The far field characteristics are presented for the reflectors shaped as quite large-size curved strips of elliptic, parabolic, and hyperbolic profiles.

Kuyucuoglu F. - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of thin dielectric cylindrical reflector having an arbitrary Conic Section profile illuminated by complex line source: H-polarization case
    'Institute of Electrical and Electronics Engineers (IEEE)', 2014
    Co-Authors: Oguzer T., Kuyucuoglu F., Altintas A.
    Abstract:

    Arbitrary Conic Section profile and thin dielectric reflector is analyzed by using the Method of Analytical Regularization (MAR) technique based on Riemann-Hilbert problem and Fourier inversion procedures. The reflector surface is assumed to be illuminated by an H-polarized complex line source type feed antenna. The convergence of the solution is verified and some changes in the radiation patterns are obtained especially for rather thicker cases. © 2014 IEEE

  • 2014 INTERNATIONAL CONFERENCE ON MATHEMATICAL METHODS IN ELECTROMAGNETIC THEORY (MMET)
    2014
    Co-Authors: Kuyucuoglu F.
    Abstract:

    Parabolic Conic Section profile, cylindrical metamaterial reflector antenna radiation characteristic is analyzed by using the Method of Analytical Regularization (MAR) techniques. E polarized complex source point is located at the focal point is used to illuminate the antenna. Far field radiation patterns are obtained for metamaterial and dielectric cases

  • Analysis of an arbitrary-profile, cylindrical, impedance reflector surface illuminated by an E-polarized complex line source beam
    'Informa UK Limited', 2014
    Co-Authors: Kuyucuoglu F., Oǧuzer T., Altintas A.
    Abstract:

    Electromagnetic scattering from a cylindrical reflector surface having an arbitrary Conic Section profile is studied. We assumed an electrically thin layer antenna illuminated by a complex line source in E-polarization mode. Our boundary value formulation, without loss of generality, involves an integral equation approach having impedance-type thin-layer boundary conditions. For simplicity, we also considered both faces of the reflector of the same uniform impedance value. Our computation employs the Method of Analytical Regularization (MAR) technique: the integral equations are converted into the discrete Fourier transform domain yielding two coupled dual series equations, which are then solved by the Fourier inversion and Riemann Hilbert Problem techniques. We demonstrate the accuracy and the convergence behaviors of our numerically solved MAR results that can serve as an accurate benchmark for comparison with widely used results obtained by approximate boundary conditions. © 2013 Taylor and Francis

  • Analysis of an arbitrary-profile, cylindrical, impedance reflector surface illuminated by an E-polarized complex line source beam
    'Informa UK Limited', 2014
    Co-Authors: Kuyucuoglu F., Oguzer T., Altintas A.
    Abstract:

    Cataloged from PDF version of article.Electromagnetic scattering from a cylindrical reflector surface having an arbitrary Conic Section profile is studied. We assumed an electrically thin layer antenna illuminated by a complex line source in E-polarization mode. Our boundary value formulation, without loss of generality, involves an integral equation approach having impedance-type thin-layer boundary conditions. For simplicity, we also considered both faces of the reflector of the same uniform impedance value. Our computation employs the Method of Analytical Regularization (MAR) technique: the integral equations are converted into the discrete Fourier transform domain yielding two coupled dual series equations, which are then solved by the Fourier inversion and Riemann Hilbert Problem techniques. We demonstrate the accuracy and the convergence behaviors of our numerically solved MAR results that can serve as an accurate benchmark for comparison with widely used results obtained by approximate boundary conditions

Y Rahmatsamii - One of the best experts on this subject based on the ideXlab platform.

  • experimental demonstration of reflectarrays acting as Conic Section subreflectors in a dual reflector system
    IEEE Transactions on Antennas and Propagation, 2013
    Co-Authors: Harish Rajagopalan, Y Rahmatsamii
    Abstract:

    This paper experimentally demonstrates the use of a microstrip reflectarray as a low-profile planar substitute to a Conic Section subreflector (hyperboloidal type) in a symmetric dual reflector system at Ku-band. At first, a brief discussion on the simulation and measurement techniques utilized in the paper is provided. A nominal dual reflector Cassegrain system is synthesized through simulations where a feed horn is used to illuminate the hyperboloidal subreflector. Next, a flat metallic subreflector is placed at the subreflector location. This is a critical task as it shows the importance of phase compensation. Due to the flat subreflector, the feed is defocused from the image of the focus and creates phase aberration, leading to beam bifurcation, pattern degradation, and performance deterioration of the dual reflector system. A planar microstrip patch-type subreflectarray is then designed to mimic a hyperboloidal subreflector. Ray tracing is applied to the subreflector-feed system to calculate the phase needed to compensate for the axial defocusing of the feed. A prototype subreflectarray based on the ray-optics approach is fabricated. Radiation pattern measurements and back-projection holographic diagnostics demonstrate that the subreflectarray acts as a hyperboloidal subreflector and restores the antenna performance with a well-defined main beam and low side lobes.

  • a novel beam squint compensation technique for circularly polarized Conic Section reflector antennas
    IEEE Transactions on Antennas and Propagation, 2010
    Co-Authors: Shenheng Xu, Y Rahmatsamii
    Abstract:

    Beam squint generally exists in offset reflector antennas with circularly polarized feeds. It is manifested by a small beam shift of the radiation pattern in the plane perpendicular to the principal offset plane, which can significantly affect the beam pointing accuracy. In this paper a practical and widely applicable compensation technique for the beam squint is proposed. Simulation results show that a small lateral feed displacement in the perpendicular plane can effectively minimize or eliminate the linear phase shift caused by the depolarization effect, thus compensating for the beam squint effect. This is in practice very useful for offset reflector antennas where the previously suggested method based on feed tilting may not be proper. A simple formula is derived to quickly estimate the optimal feed displacement for both right- and left-hand circularly polarized feeds. Three representative examples: a single offset parabolic reflector, a suboptimal offset Cassegrain reflector, and an axially symmetric Cassegrain reflector with an off-focus feed, are presented to validate the proposed method. Satisfactory results are achieved for all three examples.

Taner Oguzer - One of the best experts on this subject based on the ideXlab platform.

  • analysis of an arbitrary Conic Section profile cylindrical reflector antenna h polarization case
    IEEE Transactions on Antennas and Propagation, 2004
    Co-Authors: Taner Oguzer, A I Nosich, Ayhan Altintas
    Abstract:

    Two-dimensional scattering of waves by a perfectly electric conducting reflector having arbitrary smooth profile is studied in the H-polarization case. This is done by reducing the mixed-potential integral equation to the dual-series equations and carrying out analytical regularization. To simulate a realistic primary feed, directive incident field is taken as a complex source point beam. The proposed algorithm shows convergence and efficiency. The far field characteristics are presented for the reflectors shaped as quite large-size curved strips of elliptic, parabolic, and hyperbolic profiles.