Elektronik ve Haberleşme Mühendisliği Bölümü Yayın Koleksiyonu: Recent submissions

  • Influence of turbulence on the effective radius of curvature of radial Gaussian array beams 
    Ji, Xiaohong; Eyyuboğlu, Halil T.; Baykal, Yahya (Optical Society of America, 2010-03-29)
    The analytical formula for the effective radius of curvature of radial Gaussian array beams propagating through atmospheric turbulence is derived, where coherent and incoherent beam combinations are considered. The influence ...
  • Radius of curvature variations for annular, dark hollow and flat topped beams in turbulence 
    Eyyuboğlu, Halil T.; Baykal, Yahya; Ji, X.L. (Springer, 2010-06)
    For propagation in turbulent atmosphere, the radius of curvature variations for annular, dark hollow and flat topped beams are examined under a single formulation. Our results show that for collimated beams, when examined ...
  • Propagation factors of laser array beams in turbulent atmosphere 
    Yuan, Yangsheng; Cai, Yangjian; Zhao, Chengliang; Eyyuboğlu, Halil T.; Baykal, Yahya (Taylor&Francis Ltd, 2010)
    The propagation factors of phased locked laser array beams of radial and rectangular symmetries in a turbulent atmosphere are investigated based on the extended Huygens-Fresnel integral and the Wigner distribution function. ...
  • Propagation factors of Hermite-Gaussian beams in turbulent atmosphere 
    Yuan, Yangsheng; Cai, Yangjian; Qu, Jun; Eyyuboğlu, Halil T.; Baykal, Yahya (Elsevier Science Ltd, 2010-11)
    Based on the extended Huygens-Fresnel integral and the second-order moments of the Wigner distribution function, an analytical formulae for the propagation factors (M-2-factors) of coherent and partially coherent one-dimensional ...
  • Average intensity and spreading of partially coherent standard and elegant Laguerre-Gaussian beams in turbulent atmosphere 
    Wang, F.; Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya (E M W Publishing, 2010)
    Analytical expressions for the average intensity, mean-squared beam width and angular spread of partially coherent standard and elegant Laguerre-Gaussian (LG) beams propagating in turbulent atmosphere are derived. The ...
  • Application of the complex point source method to the Schrodinger equation 
    Umul, Yusuf Ziya (Elsevier Science Ltd, 2010-11)
    The paraxial wave equation is a reduced form of the Helmholtz equation. Its solutions can be directly obtained from the solutions of the Helmholtz equation by using the method of complex point source. We applied the same ...
  • Scattered fields of conducting half-plane between two dielectric media 
    Umul, Yusuf Ziya; Yalçın, Uğur (Optical Soc Amer, 2010-07-10)
    We investigate the scattering process of plane waves by a conducting half-plane between two dielectric media by introducing novel boundary conditions, in terms of soft and hard surfaces. The cases of soft and hard half-planes ...
  • Propagation of various dark hollow beams through an optical system in turbulent atmosphere 
    Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya (Elsevier Science, 2010-10)
    The propagation of a dark hollow beam (DHB) of circular, elliptical or rectangular symmetry through aligned and misaligned ABCD optical systems in turbulent atmosphere is investigated. Analytical propagation formulae for ...
  • Annular beam scintillations in strong turbulence 
    Gerçekçioğlu, Hamza; Baykal, Yahya; Nakiboğlu, Cem (Optical Soc Amer, 2010-08)
    A scintillation index formulation for annular beams in strong turbulence is developed that is also valid in moderate and weak turbulence. In our derivation, a modified Rytov solution is employed to obtain the small-scale ...
  • Scintillation calculations for partially coherent general beams via extended Huygens-Fresnel integral and self-designed Matlab function 
    Eyyuboğlu, Halil T.; Baykal, Yahya; Cai, Y. (Springer, 2010-09)
    We present scintillation calculations in weak atmospheric turbulence for partially coherent general beams based on the extended Huygens-Fresnel integral and a Matlab function designed to handle expressions both of the ...
  • Partially coherent elegant Hermite-Gaussian beams 
    Wang, F.; Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya; Çil, Celal Zaim (Springer, 2010-09)
    Elegant Hermite-Gaussian beams (EHGBs) are extended to the partially coherent case. An explicit and analytical formula is derived for the cross-spectral density of a partially coherent EHGB propagating through an aligned ...
  • Partially coherent off-axis Gaussian beam scintillations 
    Baykal, Yahya; Eyyuboğlu, Halil T.; Cai, Yangjian (Taylor&Francis Ltd, 2010)
    The scintillation index at the receiver origin is formulated for a partially coherent off-axis Gaussian beam in atmospheric turbulence by employing the extended Huygens-Fresnel principle. Our formula correctly reduces to ...
  • Abstraction-based verification of codiagnosability for discrete event systems 
    Schmidt, Klaus Werner (Pergamon-Elsevier Science LTD, 2010-09)
    In this paper, we investigate the verification of codiagnosability for discrete event systems (DES). That is, it is desired to ascertain if the occurrence of system faults can be detected based on the information of multiple ...
  • An analysis on radius of curvature aspects of hyperbolic and sinusoidal Gaussian beams 
    Eyyuboğlu, Halil T.; Ji, Xiaoling (Springer, 2010-10)
    The effective radius of curvature of hyperbolic and sinusoidal Gaussian beams in free space and turbulent atmosphere is studied analytically and numerically. It is shown that the radius of curvature rises with growing ...
  • Radiation of scalar waves by the discontinuities in the antenna geometries 
    Umul, Yusuf Ziya (Springer, 2010-10)
    The electrical scalar potential satisfies the Helmholtz equation for time-harmonic waves and Aharonov-Bohm showed that the electromagnetic potentials have physical reality. For these reasons, the scalar potential represents ...
  • Uniform boundary diffraction wave theory of Rubinowicz 
    Umul, Yusuf Ziya (Optical Soc Amer, 2010-07)
    Rubinowicz introduced a uniform asymptotic evaluation of the boundary diffraction wave at the transition region [Ann. Phys. (Leipzig) 378, 339 (1924)]. The uniform theory of Rubinowicz is generalized for the improved ...
  • Scintillations of partially coherent Laguerre Gaussian beams 
    Yüceer, Mehmet; Eyyuboğlu, Halil T.; Lukin, I. P. (Springer, 2010-12)
    Scintillations of Laguerre-Gaussian (LG) beams for weak atmospheric turbulence conditions are derived for on-axis receiver positions by using Huygens-Fresnel (HF) method in semi-analytic fashion. Numerical evaluations ...
  • Effect of the shadow geometry in wedge diffraction 
    Umul, Yusuf Ziya (Optical Soc Amer, 2009-09-01)
    The surface integrals of the modified theory of physical optics are divided into two parts for diffraction by a wedge. Each integral represents the incident or reflected field scattered by one of the faces of the wedge. ...
  • Intensity fluctuations in J-Bessel-Gaussian beams of all orders propagating in turbulent atmosphere 
    Eyyuboğlu, Halil T.; Sermutlu, Emre; Baykal, Yahya; Cai, Yangjian; Korotkova, Olga (Springer, 2008-11)
    The scintillation index of a J (n) -Bessel-Gaussian beam of any order propagating in turbulent atmosphere is derived and numerically evaluated at transverse cross-sections with the aid of a specially designed triple integral ...
  • Scintillations of Laguerre Gaussian beams 
    Eyyuboğlu, Halil T.; Baykal, Yahya; Ji, X. (Springer, 2010-03)
    By using the Rytov method, we formulate and numerically evaluate the scintillations of Laguerre Gaussian beams in weak atmospheric turbulence. Our results indicate that at on-axis positions, Laguerre Gaussian beams with ...