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Parametric Characterization of Truncated Circular Flattened Gaussian Beams
Redouane Lamsoudi,
Mohammed Ibn Chaikh
Issue:
Volume 3, Issue 1, February 2015
Pages:
1-4
Received:
27 May 2015
Accepted:
15 June 2015
Published:
2 July 2015
Abstract: Based on the truncated second-order moments definition, the generalized factor of the circular flattened Gaussian beams (CFGB) in the cylindrical coordinate system through a hard-edged circular aperture is derived. Three special cases have been obtained from the closed-form expression for the generalized factor of the truncated CFGB, the non-truncated CFGB, the truncated and non-truncated Gaussian beams. The power fraction of the CFGB is calculated analytically and illustrated numerically.
Abstract: Based on the truncated second-order moments definition, the generalized factor of the circular flattened Gaussian beams (CFGB) in the cylindrical coordinate system through a hard-edged circular aperture is derived. Three special cases have been obtained from the closed-form expression for the generalized factor of the truncated CFGB, the non-trunca...
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Performance Analysis of Coherent Optical OFDM Applied to UAV Mobile FSO Systems
Konstantinos Eleftherios Zarganis,
Antonis Hatziefremidis
Issue:
Volume 3, Issue 1, February 2015
Pages:
5-12
Received:
2 June 2015
Accepted:
15 June 2015
Published:
2 July 2015
Abstract: The Free Space Optical (FSO) communication links is a promising and cost-effective solution for the provision of high data rate point to point communications. Due to their huge bandwidth, license free spectrum and multipath fading mitigation, the FSO links combined with Orthogonal Frequency Division Multiplexing (OFDM) modulation technique provide an ideal communication solution between Unmanned Aerial Vehicles (UAVs) and fixed Ground Station (GS). In order to design a high performance communication link, it is important to characterize the quality of the optical channel with a proper model, considering the interesting challenges of environmental conditions, such as turbulence and visibility conditions. In this paper we are studying the performance of a mobile link among co-moving UAVs, UAV and GS at different fixed altitudes and link ranges via Optisystem simulation platform, in terms of Bit Error Rate (BER), Optical Signal to Noise Ratio (OSNR) and constellation diagrams. An extensive, comparative analysis among different FSO configurations links considering various characteristics of the OFDM modulation, link ranges, Bit Rates (BR) and the atmospherical conditions is provided.
Abstract: The Free Space Optical (FSO) communication links is a promising and cost-effective solution for the provision of high data rate point to point communications. Due to their huge bandwidth, license free spectrum and multipath fading mitigation, the FSO links combined with Orthogonal Frequency Division Multiplexing (OFDM) modulation technique provide ...
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Study of the Electrons Density in the Base of the Parallel Vertical Junction Solar Cell Under the Influence of the Temperature
Issue:
Volume 3, Issue 1, February 2015
Pages:
13-16
Received:
10 July 2015
Accepted:
22 July 2015
Published:
29 July 2015
Abstract: This work is a theoretical study of a parallel vertical junction solar cell under multispectral illumination in static regime. The expression for the density of the minority carriers in excess (electrons) in the base is determined from the equation of continuity. It's an equation that takes into account the process of generation of the charge carriers, the process of diffusion of these carriers and their processes of recombination process. The aim of this work is to study the evolution of this density depending on temperature and its distribution in depth following x and the thickness z in the base for different values of the temperature.
Abstract: This work is a theoretical study of a parallel vertical junction solar cell under multispectral illumination in static regime. The expression for the density of the minority carriers in excess (electrons) in the base is determined from the equation of continuity. It's an equation that takes into account the process of generation of the charge carri...
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Population Inversion and X-Ray Laser Gain by Electron Impact Excitation of Ni-Like Tin
Mahmoud Ahmad,
Ahmed Abou El-Maaref,
Essam Abdel-Wahab,
Sami Allam
Issue:
Volume 3, Issue 1, February 2015
Pages:
17-23
Received:
11 July 2015
Accepted:
22 July 2015
Published:
30 July 2015
Abstract: Excitation energies and transition probabilities for the 1s22s22p63s23p63d10, and the 1s22s22p63s23p63d94l (l= s, p, d, and f) configurations in nickel-like tin have been used to calculate the reduced population of 99 fine structure levels over a wide range of electron densities and at different electron plasma temperatures. The gain coefficients for those transitions with positive population inversion factors have been calculated as a function of electron density. This study is concerned with the transitions which produce positive gain at XUV and X-ray spectral regions.
Abstract: Excitation energies and transition probabilities for the 1s22s22p63s23p63d10, and the 1s22s22p63s23p63d94l (l= s, p, d, and f) configurations in nickel-like tin have been used to calculate the reduced population of 99 fine structure levels over a wide range of electron densities and at different electron plasma temperatures. The gain coefficients ...
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