WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653

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  • Conference Object
    Review on the Modified Theory of Physical Optics
    (Ieee, 2018) Basdemir, Husnu Deniz; Basdemir, Husnu Deniz
    In this review, modified theory of physical optics approach to the diffraction problem is revisited. The important aspects of the method are explained and steps for the usage of the method are revealed. Also, historical progress of the method is mentioned.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 4
    Po and Ptd Approach To the Diffraction Problem by a Resistive Half-Plane
    (Taylor & Francis Ltd, 2014) Basdemir, Husnu Deniz
    Diffracted fields from a resistive half-plane were investigated by the method of physical optics (PO) and the physical theory of diffraction. The coefficient of the PO scattering integral was derived for the first time for the resistive half-plane. Uniform fringe field expressions were obtained in terms of the Fresnel functions. The resultant expressions of the fringe fields were plotted and analyzed numerically.
  • Conference Object
    Method of Total Fields for Diffraction Problems Between Different Media
    (Ieee, 2019) Basdemir, Husnu Deniz
    In this present study a new method which gives the scattered field by a canonical structure between two different media is introduced. This method is applied to the half-plane with soft boundary condition. The fields are examined numerically. Thus, numerical analysis showed that the proposed method is suitable for these kinds of problems.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 5
    Diffraction of Electromagnetic Waves by a Planar Interface Between Perfectly Absorbing and Anomalously Transmitting Metasurface Half-Planes
    (Elsevier Gmbh, 2019) Umul, Yusuf Ziya
    The interaction process of electromagnetic waves by a planar interface between perfectly absorbing and anomalously refracting metasurface half-planes is investigated. First of all, the scattered geometric optics field is obtained from the difference of the total geometric optics and initial waves. The diffracted fields are determined by using a relation between the scattered geometric optics and diffraction waves at the transition boundaries. It consists of the diffraction fields of perfectly absorbing and anomalously refracting metasurface half-screens. The behaviors of the total, total geometric optics and diffracted waves are studied numerically.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Interaction of Electromagnetic Waves by a Cylindrical Parabolic Mesh Reflector
    (Elsevier Gmbh, 2019) Umul, Yusuf Ziya
    A cylindrical parabolic reflector, composed of mesh grid, is modeled by a resistive surface. The analysis of the scattered waves is performed by the physical optics integral, which was developed for resistive surfaces. The integral is evaluated asymptotically for large values of the wave-number in high-frequencies. The geometrical optics and diffracted fields are obtained by the methods of stationary phase and edge point respectively. The uniform forms of the diffracted waves are derived. The total wave and its components are investigated numerically for different values of surface resistivity.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 11
    Wave Diffraction by the Junction Between Resistive and Soft-Hard Half-Screens
    (Elsevier Gmbh, Urban & Fischer verlag, 2017) Umul, Yusuf Ziya
    The scattering process of planes waves by a junction between resistive and soft/hard half-planes is investigated. First of all, the initial and total geometrical optics fields are determined by considering the related geometries. The scattered geometrical optics wave is obtained by subtracting the initial field from the total geometrical optics wave. The diffracted fields are derived by taking into account the behaviour of the geometrical optics wave at the reflection and shadow boundaries. The uniform expressions of the diffracted waves are constructed with the aid of the uniform theory of diffraction. The total field expressions are examined numerically. (C) 2016 Elsevier GmbH. All rights reserved.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Scattering of Waves by a Soft-Hard Half-Plane Between Isorefractive Medium
    (Taylor & Francis Ltd, 2017) Umul, Yusuf Ziya
    The scattering of plane waves by a soft-hard half-plane residing between isorefractive medium is studied. The scattered geometrical optics fields are obtained by subtracting the initial geometrical optics fields from the total geometrical optics waves. The diffracted fields are determined by considering the structure of the scattered geometrical optics waves. The uniform expressions for the diffracted fields are derived. The behaviour of the total waves is investigated numerically.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    An Analytical Solution for the Plane Wave Diffraction by a Resistive Half-Plane Residing at the Interface of Left and Right Handed Media
    (Elsevier Gmbh, 2019) Basdemir, Husnu Deniz
    The diffraction of waves by a resistive half-plane lying on the interface of left and right handed media is investigated in this study. Because of the anomalous refraction property of left handed media, shadow boundary shifts toward to the lower surface of the half-plane. In order to obtain the shifted boundary, diffracted waves are divided to subfields. Thus, obtained diffracted waves compensates the deficiency of geometries optics fields at the transition regions. The uniform version of waves is obtained by using the uniform theory of diffraction. The wave behaviors are examined numerically.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 5
    Wave Diffraction by a Right-Angled Interface Between Resistive Half and Whole Planes
    (Elsevier Gmbh, Urban & Fischer verlag, 2018) Umul, Yusuf Ziya
    The interaction phenomenon of electromagnetic plane waves by a right angled interface between whole and half screens with different resistivities is studied. The construction, under examination, is considered in order to model various corner discontinuities between transmissive surfaces for indoor wireless communications. First of all, the initial waves, which occur in the absence of the diffracting edge, are determined. Then the scattered geometrical optics fields are obtained by subtracting the initial waves from the total geometrical optics fields. The diffracted field is constructed directly from the scattered geometrical optics wave by a new method. The resultant field expressions are examined numerically.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Wedge Diffraction Model in Gravitational Lensing by Cosmic Strings
    (Elsevier Gmbh, 2018) Umul, Yusuf Ziya
    A cosmic string forms a conical topology, which enables a diffraction phenomenon by a wedge with an inner angle, equals to the double of the deficit angle. A wedge, on the edge of which the string is located, is defined in the flat space-time. The radiated wave from a star is represented by two plane waves, propagating on the two surfaces of the wedge for grazing incidence. The uniform expressions of the diffracted waves are obtained and investigated numerically. (C) 2017 Elsevier GmbH. All rights reserved.