Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Citation - WoS: 23Citation - Scopus: 23Ber of Asymmetrical Optical Beams in Oceanic and Marine Atmospheric Media(Elsevier Science Bv, 2017) Baykal, YahyaThe average bit-error-rate (BER) performances of asymmetrical optical Gaussian beams propagating in oceanic and marine atmospheric turbulence are examined. Both type of media are assumed to exhibit weak turbulence. The effect of asymmetry factor on the BER performance are investigated in conjunction with the oceanic turbulence parameters of the ratio of temperature to salinity contributions to the refractive index spectrum, the rate of dissipation of mean-squared temperature and the rate of dissipation of kinetic energy per unit mass of fluid, and with the marine atmospheric link parameters of the link length and the structure constant. Also, the variations of the BER against the source size of various asymmetrical beams are scrutinized in both oceanic and marine atmospheric media.Article Citation - WoS: 24Citation - Scopus: 26Scintillation and Ber for Optimum Sinusoidal Gaussian Beams in Weak Non-Kolmogorov Turbulence(Elsevier Science Bv, 2014) Gercekcioglu, Hamza; Baykal, YahyaThe scintillation index and the average bit error rate (BER) are evaluated for the optimum sinusoidal Gaussian beams in weak non-Kolmogorov turbulence. The beam parameters that minimize the scintillation index and the average BER are stated and such beams are denoted as the optimum beams. For the collimated Gaussian, cos- and cosh-Gaussian beams, the scintillations increase as the power law exponent, a increases. Cos- and cosh-Gaussian beams that have larger absolute displacement parameters are found to exhibit larger scintillations especially at small a. Larger focal length and larger source size of cos-Gaussian beams induce reduction in the scintillations. When the propagation distance is large, the power law exponent is small and the source size is large, the scintillations of the optimum beams tend to decrease. Small power law exponent and large source size reduce the average BER. The optimum beam is shown to exhibit the smallest average BER for any a. (C) 2014 Elsevier B.V. All rights reserved.Article Citation - WoS: 9Citation - Scopus: 11Application of Equivalent Structure Constant in Scintillations and Ber Found for Non-Kolmogorov Spectrum(Elsevier Science Bv, 2014) Baykal, Yahya; Gercekcioglu, HamzaThe evaluation of system parameters in the non-Kolmogorov turbulent atmosphere involves the structure constant valid at the relevant non-Kolmogorov power law exponent. In some of the existing results, the comparisons of system parameters found under the Kolmogorov and non-Kolmogorov turbulences were made by using the same structure constant for all the power law exponents of the non-Kolmogorov spectrum. In this paper, we evaluate the scintillations and the average Bit Error Rate (< BER >) for the flat-topped and the annular beams in non-Kolmogorov turbulence, this time using the equivalent structure constant which is now different for all the power law exponents. It is observed that the scintillations and the < BER > show completely different behaviour when evaluated with the equivalent structure constant as compared to evaluations with constant structure constant. (C) 2013 Elsevier B.V. All rights reserved.