Harilaos G. Sandalidis

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Optical wireless, also known as free-space optics, has received much attention in recent years as a cost-effective, licensefree and wide-bandwidth access technique for high data rates applications. The performance of free-space optical (FSO) communication, however, severely suffers from turbulence-induced fading caused by atmospheric conditions. Multiple(More)
In this letter, we investigate the error rate performance of free-space optical (FSO) links over strong turbulence fading channels together with misalignment (pointing error) effects. First, we present a novel closed-form expression for the distribution of a stochastic FSO channel model which takes into account both atmospheric turbulence-induced fading and(More)
Modern cellular mobile communications systems are characterized by a high degree of capacity. Consequently, they have to serve the maximum possible number of calls while the number of channels per cell is limited. The objective of channel allocation is to assign a required number of channels to each cell such that both efficient frequency spectrum(More)
The performance of a ground-station-to-space laser uplink with a Gaussian-beam wave model subject to turbulence and beam wander effects is the topic of the present study. The modulated gamma distribution is used to describe the combined effect of the above two deteriorating factors. At first, a versatile expression of the above probability density function(More)
In this paper, we propose a new probability distribution function which accurately describes turbulence-induced fading under a wide range of turbulence conditions. The proposed model, termed Double GG distribution, is based on a doubly stochastic theory of scintillation and developed via the product of two Generalized Gamma (GG) distributions. The proposed(More)
Transferring wireless broadband services across extremely far distances on Earth is usually implemented nowadays either by ground-based or satellite communications. Terrestrial networks require, however, heavy installation and maintenance costs, whereas satellite networks suffer from excessively high power requirements. An alternative but highly challenging(More)
In this paper, we study the performance of multihop free-space optical (FSO) wireless systems over turbulenceinduced fading channels. The analysis is carried out for systems employing amplify-and-forward (AF) or decode-and-forward (DF) relays and for turbulence channels which can be modeled by the Gamma-Gamma distribution. An exact analytical expression for(More)
The use of relays is one of the most promising methods for mitigating impairments of the performance of free-space optical (FSO) systems and extending their limited transmission range. However, several factors contribute to significant link performance degradation. Most severe is the influence of the adverse atmospheric conditions that frequently appear,(More)
Free-space optical (FSO) communication has received much attention in recent years as a cost-effective, licensefree and wide-bandwidth access technique for high data rates applications. The performance of FSO communication, however, severely suffers from turbulence-induced fading caused by atmospheric conditions. Multiple laser transmitters and/or receivers(More)