Browsing by Author "Kamacioglu, Canan"

Now showing 1 - 6 of 6

Citation - WoS: 8
Citation - Scopus: 9
Aperture averaging in multiple-input single-output free-space optical systems
(Spie-soc Photo-optical instrumentation Engineers, 2015) Gokce, Muhsin C.; Gökçe, Muhsin Caner; Baykal, Yahya; Kamacioglu, Canan; Uysal, Murat; 28643; 7812; 124615
Multiple-input single-output systems are employed in free-space optical links to mitigate the degrading effects of atmospheric turbulence. We formulate the power scintillation as a function of transmitter and receiver coordinates in the presence of weak atmospheric turbulence by using the extended Huygens Fresnel principle. Then the effect of the receiver aperture averaging is quantified. To get consistent results, parameters are chosen within the range of validity of the wave structure functions. Radial array beams and a Gaussian weighting aperture function are used at the transmitter and the receiver, respectively. It is observed that the power scintillation decreases when the source size, the ring radius, the receiver aperture radius, and the number of array beamlet increase. However, increasing the number of array beamlets to more than three seems to have negligible effect on the power scintillation. It is further observed that the aperture averaging effect is stronger when radial array beams are employed instead of a single Gaussian beam. (C) 2015 Society of Photo-Optical Instrumentation Engineers (SPIE)
Citation - WoS: 12
Citation - Scopus: 12
Averaging of receiver aperture for flat-topped incidence
(Elsevier Sci Ltd, 2013) Kamacioglu, Canan; Baykal, Yahya; Yazgan, Erdem; 7812
Using a flat-topped profile for the incident beam, the power scintillation index for weak atmospheric turbulence is formulated and analytically evaluated. Through the use of the aperture averaging factor, the averaging effect of the finite receiver aperture on the intensity fluctuations for a flat-topped incident beam is examined. The influence of the order of flatness on the averaging is investigated. At large propagation lengths, increasing the flatness parameter decreases the power scintillations and it is possible to further reduce the scintillation by increasing the receiver aperture. Increasing the structure constant increases this effect. (C) 2013 Elsevier Ltd. All rights reserved.
Citation - WoS: 11
Citation - Scopus: 11
Generalized expression for optical source fields
(Elsevier Sci Ltd, 2012) Kamacioglu, Canan; Baykal, Yahya; 7812
A generalized optical beam expression is developed that presents the majority of the existing optical source fields such as Bessel, Laguerre-Gaussian, dark hollow, bottle, super Gaussian, Lorentz, super-Lorentz, flat-topped, Hermite-sinusoidal-Gaussian, sinusoidal-Gaussian, annular, Gauss-Legendre, vortex, also their higher order modes with their truncated, elegant and elliptical versions. Source intensity profiles derived from the generalized optical source beam fields are checked to match the intensity profiles of many individual known beam types. Source intensities for several interesting beam combinations are presented. Our generalized optical source beam field expression can be used to examine both the source characteristics and the propagation properties of many different optical beams in a single formulation. (C) 2012 Elsevier Ltd. All rights reserved.
Citation - WoS: 5
Citation - Scopus: 7
Performance analysis of mimo fso systems with radial arraybeams and finite sized detectors
(Spie-int Soc Optical Engineering, 2014) Gokce, Muhsin C.; Gökçe, Muhsin Caner; Kamacioglu, Canan; Uysal, Murat; Baykal, Yahya
Multiple-input multiple-output (MIMO) systems are employed in free space optical (FSO) links to mitigate the degrading effects of atmospheric turbulence. In this paper, we consider a MIMO FSO system with practical transmitter and receiver configurations that consists of a radial laser array with Gaussian beams and finite sized detectors. We formulate the average received intensity and the power scinitillation as a function of the receiver coordinates in the presence of weak atmospheric turbulence by using the extended Huygens-Fresnel principle. Then, integrations over the finite sized multiple detectors are performed and the effect of the receiver aperture averaging is quantified. We further derive an outage probability expression of this MIMO system in the presence of turbulence-induced fading channels. Using the derived expressions, we demonstrate the effect of several practical system parameters such as the ring radius, the number of array beamlets, the source size, the link length, structure constant and the receiver aperture radius on the system performance.
Citation - WoS: 5
Citation - Scopus: 6
Propagation of Optical Flat-Topped Gaussian Beams in Satellite Links
(Ieee, 2009) Kamacioglu, Canan; Arpali, Serap A.; Baykal, Yahya; Yazgan, Erdem
Propagation of optical flat-topped Gaussian beams in earth-satellite optical communication links is investigated where part of the link is turbulent atmosphere. Flat-topped Gaussian source field is obtained by superposing many Gaussian beams of different source size. Starting with the flat-topped Gaussian incidence at the earth surface, the average intensity at the satellite is formulated by using the extended Huygens Fresnel principle. For the structure constant variation versus height, Hufnagel-Valley model is employed in the vertical and slant paths. The received average intensity is numerically calculated and the effects of the source and medium parameters on the received average intensity profile are examined for different zenith angles. In earth-satellite optical communications links, the advantages of using flat-topped Gaussian beams as compared to Gaussian beams are scrutinized.
Citation - WoS: 10
Citation - Scopus: 9
Receiver-aperture averaging of annular beams propagating through turbulent atmosphere
(Spie-soc Photo-optical instrumentation Engineers, 2013) Kamacioglu, Canan; Baykal, Yahya; Yazgan, Erdem; 7812; 7278
For an annular beam incidence, the power scintillation index in a weakly turbulent atmosphere is derived at the receiver plane, which has a Gaussian aperture. Employing this derivation, the receiver-aperture averaging factor is evaluated. Annular beams are found more advantageous than the Gaussian beams when compared on receiver-aperture averaging basis. The analyses indicate that the effect of the aperture averaging increases as the propagation length increases. Increase in the structure constant and the secondary beam source size is observed to strengthen the effect of the aperture averaging when the primary beam source size is fixed. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)