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Konu "Atmospheric Turbulence" için Elektronik ve Haberleşme Mühendisliği Bölümü listeleme

Konu "Atmospheric Turbulence" için Elektronik ve Haberleşme Mühendisliği Bölümü listeleme

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  • Equivalence of structure constants in non-Kolmogorov and Kolmogorov spectra 
    Baykal, Yahya; Gerçekçioğlu, Hamza (Optical Soc Amer, 2011-12-01)
    We find the equivalence of the structure constants in non-Kolmogorov and Kolmogorov spectra in a turbulent atmosphere. As the reference point, the spherical wave scintillation index in a non-Kolmogorov medium is used. ...
  • Estimation of scintillation and bit error rate performance of sine hollow beam via random phase screen 
    Bayraktar, Mert (Elsevier GMBH, 2019)
    We study scintillation and bit error rate performance of sine hollow beam in turbulent atmosphere. Since source field expression involves higher order term, we model atmosphere utilizing random phase screen. We show that ...
  • Field correlations for off-axis Gaussian laser beams in atmospheric turbulence 
    Baykal, Yahya (Amer Geophysical Union, 2014-10)
    The absolute field correlations in atmospheric turbulence are evaluated for the off-axis optical Gaussian beam incidence. Evaluations in the practical range of the source and the turbulent medium parameters show that an ...
  • Field correlations of flat-topped Gaussian and annular beams in turbulence 
    Baykal, Yahya (Elsevier Science Ltd, 2011-05)
    Starting from the second order moment formulation for multi-beam incidence, field correlations at the receiver plane of flat-topped Gaussian and annular beams are found in turbulence. Reflecting the information on both the ...
  • Incoherent sinusoidal-Gaussian and annular beam scintillations 
    Baykal, Yahya; Eyyuboğlu, Halil T.; Cai, Yangjian (Spie-Int Soc Optical Engineering, 2008)
    The scintillation index is evaluated in horizontal turbulent atmospheric optical links for incidences of incoherent cosh-Gaussian (IChG), cos-Gaussian (ICG) and annular (IA) beams. Weak turbulence solution is obtained for ...
  • 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 ...
  • Intensity fluctuations for source arrays in turbulent atmosphere - art. no. 630308 
    Baykal, Yahya (Spie-Int Soc Optical Engineering, 2006)
    Intensity fluctuations are formulated for source arrays in weakly turbulent horizontal atmospheric links. Source array is composed of point sources separated by variable distances in the transverse source directions. Formula ...
  • Intensity fluctuations of flat-topped beam in non-Kolmogorov weak turbulence 
    Gerçekçioğlu, Hamza; Baykal, Yahya (Optical Soc Amer, 2012-09)
    Results obtained on the intensity fluctuations of flat-topped Gaussian beams in weakly turbulent non-Kolmogorov horizontal atmospheric optics links are represented. Effects on the scintillation index of the power law a ...
  • Intensity fluctuations of focused general-type beams in atmospheric optics links 
    Baykal, Yahya; Eyyuboğlu, Halil T. (Spie-Int Soc Optical Engineering, 2007)
    The intensity fluctuations of focused general-type beams in weakly turbulent atmospheric links are formulated and numerically evaluated. Focused general-type beams in general cover very large range of beams, however in ...
  • Intensity fluctuations of partially coherent cos Gaussian and cosh Gaussian beams in atmospheric turbulence 
    Baykal, Yahya; Eyyuboğlu, Halil T.; Çil, Celal Zaim; Cai, Yangjian; Korotkova, Olga (IOP Publishing Ltd, 2011-05)
    On-axis and off-axis scintillation indices of partially coherent collimated cos Gaussian and cosh Gaussian beams are evaluated on their propagation in a weakly turbulent atmosphere. In the coherent limits, our results are ...
  • Irradiance fluctuations of partially coherent super Lorentz Gaussian beams 
    Gökçe, Muhsin Caner; Eyyuboğlu, Halil T. (Elsevier Science BV, 2011-09-15)
    By using the semi-analytic approach introduced earlier, we formulate and subsequently evaluate the irradiance fluctuations of partially coherent super Lorentz Gaussian beams for orders of 10 and 11. Within the range of ...
  • Minimization of scintillation index against displacement parameters 
    Eyyuboğlu, Halil T.; Gerçekçioğlu, Hamza; Baykal, Yahya (Elsevier Science, 2008-09-01)
    For sinusoidal beams, minimization of scintillation index is carried out against the displacements parameters. It is found-that x-y asymmetric cosh-Gaussian beam fulfills the requirements of such optimum beam. Our minimization ...
  • Off-axis Gaussian beams with random displacement in atmospheric turbulence 
    Baykal, Yahya; Eyyuboğlu, Halil T.; Yenice, Yusuf E. (Int Inst Informatics & Systemics, 2005)
    Our recent work in which we study the propagation of the general Hermite-sinusoidal-Gaussian laser beams in wireless broadband access telecommunication systems is elaborated in this paper to cover the special case of an ...
  • Off-axis-Gaussian beam intensity in random medium 
    Baykal, Yahya; Eyyuboğlu, Halil T. (Elsevier Science, 2007-01-01)
    The receiver intensity profile of an off-axis-Gaussian beam travelling in random medium is formulated. By examining the related exponential terms of this intensity expression, the rules governing the receiver plane ...
  • 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 ...
  • Propagation characteristics of higher-order annular Gaussian beams in atmospheric turbulence 
    Eyyuboğlu, Halil T.; Altay Arpalı, Serap; Baykal, Yahya (Elsevier Science, 2006-02-15)
    The propagation characteristics of higher-order annular Gaussian (HOAG) beams in turbulence are investigated. From a HOAG source plane excitation, the average intensity of the receiver plane is developed analytically. This ...
  • Propagation of cross beams through atmospheric turbulence 
    Yenice, Y. E.; Eyyuboğlu, Halil T.; Baykal, Yahya (Spie-Int Soc Optical Engineering, 2005)
    Propagation properties of cross beam in turbulent medium are studied. A cross beam is constructed by the sum of two highly asymmetric Gaussian beams placed along transverse axes. It is known that such beams, when propagating ...
  • 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 ...
  • Rate averaging in free space optics systems using incoherent sources 
    Baykal, Yahya (Spie-Int Soc Optical Engineering, 2004-06-23)
    Effect of the information rate on the scintillation index is examined for free space optical (FSO) broadband access applications that use spatially incoherent sources. For this purpose, intensity fluctuations are formulated ...